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HomeMy WebLinkAboutGP_UPDATE_TECHNICAL_BACKGROUND_REPORT_211111111 lill 11111111111111111111111111 lill III lill *NEW FILE* G P_U P DAT E_T E C H N I CAL_BAC KG RO UN D_RE P O RT_2 0 u �+'..it +! �{ ' v�4 Flit .� �4 r1�nl +l'� y+ }r i1N �}r,•Jr'l,;,A ! .in p' 'y�, ♦, i ..a.q ia* /, w59 +`'Xa¢" Lnr +• "E G 1 /f i "b jM+ef ,n3 4 C," #"..+�/ !1+) ea i l O o d •i a l' i e 7H a z e. i 0 it s Materials Management Section 6.7 Aviation Hazards �P ,,,l � � � o16%5,-- • Hazards Assessment Study City of Newport Beach, California Coastal Hazards Seismic Hazards Prepared for City of Newport Beach Planning Department 3300 Newport Boulevard Newport Beach, California 92658-8915 0 July 2003 Hazardous Materials Management Aviation Hazards Prepared by Earth Consultants International Earth Consultants Intemational 150 El Camino Real, Suite 212 Tustin, California 92780 (714)544-5321 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • CHAPTER 1: COASTAL HAZARDS 1.1 Physical and Historical Setting Newport Beach, located in Orange County, California, enjoys about 14.9 kilometers [km] (9.25 miles [mil) of shoreline along the Pacific Ocean, and approximately 80 km (50 mi) of waterfront if one includes the shoreline, Newport Bay, and islands within City limits. The western part of the City is characterized by a series of channels and islands that provide berthing for approximately 9,000 small boats. This harbor has been acclaimed as one of the finest small boat harbors in the world, protected from the open ocean by the Balboa Peninsula. The two main channels that form this protected harbor come together near the harbor mouth, on the southeastern side of Balboa Island, and flow out to sea, where two jetties stand as sentries against the encroaching sea. The City's beach setting provides economic, environmental and public safety benefits: money spent locally by visitors to the area's beaches generate millions of dollars in sales tax receipts that benefit not only the City of Newport Beach, but the County of Orange and the federal government. The coastal setting, including the Upper Newport Bay estuary, also provide habitat for numerous species of birds, plants, and marine animals, many of them protected or endangered. The beaches are therefore an important resource that requires protection and careful management. This seemingly natural -looking and idyllic setting is the result of relatively recent active forces of nature and even more recent man-made modifications. In fact, the present coastline of northwestern Newport Beach bears little resemblance to the coastline of the early 1800s, or even the early 1900s. Between 1769, when the Spanish first arrived in southern California, and 1825, • the Santa Ana River flowed out to sea through Alamitos Bay, near the present-day boundary between Los Angeles and Orange counties. In 1825, when severe storms caused extensive flooding in the area, the river resumed its ancient course through the Santa Ana Gap and around the toe of Newport Mesa to the ocean. The down -coast littoral drift, plus continuing floods, caused the river to build the Balboa peninsula. During the floods of 1861-1862, the river mouth swept farther to the southeast, to the rock bluffs which form the east side of the present channel entrance. Until 1919, the river outlet to the sea continued to migrate back and forth from the rock bluffs to a point about 600 meters [m] (2,000 feet [ft]) up -coast of the present channel entrance (U.S. Corps of Engineers, 1993). In 1919, a year after a serious flood, local interests built a dam at Bitter Point (which appears to have been located near present-day 57th Street and Seashore Drive) to stop the flow into Newport Bay, and cut a new outlet for the Santa Ana River, where it has remained to date. Local citizens' interest in developing a harbor reportedly dates back to the 1870s, when the McFadden brothers acquired the Newport Landing and established a commercial trade and shipping business that operated successfully for the next 15 years. In the late 1880s, the McFadden brothers built a large ocean pier near McFadden Square (the Newport Pier) and moved their entire business to the wharf. With completion of the Santa Ana Newport Railroad (later the Southern Pacific Railroad) in 1891, the McFadden area became a booming commercial and shipping center. Residential development of the area began at the turn of the century, first around the wharf, and then along the peninsula. Soils dredged from the bay to widen and deepen the channels were used to construct Balboa Island, Lido Isle and the other islands in the bay. As soon as Balboa Island and Lido Isle were constructed, they were subdivided into lots. West Newport, • Balboa, Balboa Island and Corona del Mar were subdivided between 1903 and 1907, and in Earth Consultants International Coastal Hazards Page 1-1 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 1906, the City of Newport Beach, consisting of West Newport and the Balboa Peninsula, was incorporated. Balboa Island was annexed in 1916, and Corona del Mar in 1923. The harbor entrance began to take its current shape with the construction of the original west jetty in 1918, a rubblemound structure that extended 460 m (1,500 ft) out from the end of Balboa Peninsula. In 1922, the County of Orange extended this jetty another 122 m (400 ft). The jetty suffered extensive damage due to storms that hit the area in 1920; repairs were completed in 1927-1928, when the east jetty was also constructed. The repairs to the west jetty included a long, curving revetted approach on the west side that caused the adjacent shoreline to erode completely. As a result, in 1930, the City repaired the west jetty and added two rubblemound groins. The area between the groins was filled with sand. Between 1934 and 1936, the Federal government, in cooperation with the Orange County Harbor district, extended both jetties to their present configuration. As part of the Orange County Erosion Control Project of 1964, the groin field in West Newport Beach was constructed between 1968 and 1973 (U.S. Army Corps of Engineers, 1993; Department of Boating and Waterways and State Coastal Conservancy, 2002). As the paragraphs above illustrate, the Newport Beach area as we know it today has developed rapidly, the result of man's will modifying the natural environment at a pace that far exceeds the geologic time scale. When nature is left to run its course, some processes take hundreds of thousands of years to mold the landscape, while other natural processes occur suddenly, with little or no warning. These catastrophic events tend to occur infrequently, perhaps only once every few decades, or even every few hundreds to tens of thousands of years, and so it is only relatively recently that scientists have started to fully appreciate the magnitude of the low probability but • high risk events that can shape the landscape. Furthermore, we now realize that many of these processes have the potential to destroy property and compromise the safety of people that live in areas susceptible to natural hazards. This is especially true in coastal areas, where as a result of rapid growth, large populations are now exposed to coastal hazards. This chapter discusses the coastal hazards that Newport Beach may be susceptible to, including tsunamis, rogue waves, storm surges, seiches, bluff erosion, hurricanes, changes in sea level, and degradation of water quality. Other natural and man-made hazards that can impact this portion of Orange County are discussed in subsequent chapters of this report. 1.2 jurisdictional Overview There are many agencies that are tasked with the protection and management of coastal features along the U.S. western coast, including at Newport Beach. At the federal level, the primary government agencies involved with shoreline erosion issues are the U.S. Army Corps of Engineers (Corps) and the Federal Emergency Management Agency (FEMA). Several state agencies have jurisdiction over specific coastal issues, including the California Department of Boating and Waterways (DBW), the California Coastal Commission, the California Lands Commission, the State Coastal Conservancy, the California Geological Survey (CGS), and the Department of Parks and Recreation (DPR). The Corps, DBW, and sometimes the State Coastal Conservancy are involved with funding shoreline maintenance projects, while the DPR, as a land manager, decides how and whether to re -build and/or protect its facilities after major storms. FEMA also has a variety of programs to provide assistance during or in response to major flooding and storm events. The California Coastal Commission and the State Lands Commission are the primary agencies with • regulatory authority over proposals to build coastal protective structures, while the CGS is charged Earth Consultants International Coastal Hazards Page 1-2 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • with identifying the geologic hazards in the state. Local governments, including the City of Newport Beach and Orange County, also process a number of permit actions and provide funding for shoreline protection measures. The United States Army Corps of Engineers (Los Angeles District) manages the Operations and Maintenance (O&M) Navigation Program. The O&M program includes maintenance dredging and navigation structure repair at 14 harbors along the southern California coastline, including Newport Harbor. It also provides engineering, design and plan preparation, specifications, and environmental documentation for navigation projects. Further, the O&M program establishes schedules, prepares service requests, monitors work progress, prepares and updates five-year dredging plans, and maintains database information on dredging schedules, past bid data, and post project data. Other O&M duties include: overseeing hydrographic surveys of District harbors; conducting yearly inspection of all navigation structures (to evaluate the need for repair); and contracting for the removal of wrecks and other obstructions that could cause a hazard to navigation. The functions of several of these agencies are discussed further in this chapter as they pertain to specific projects that impact the Newport Beach area. 1.3 Tsunamis and Rogue Waves A tsunami is a sea wave caused by any large-scale disturbance of the ocean floor that occurs in a short period of time and causes a sudden displacement of water. Tsunamis can travel across the . entire Pacific Ocean basin, or they can be local. For example, an earthquake off the coast of Japan could generate a tsunami that causes substantial damage in Hawaii. These distantly generated tsunamis are also referred to as teletsunamis. This report will address the potential for both teletsunamis and locally generated tsunamis impacting the Newport Beach coastline. Large-scale tsunamis are not single waves, but rather a long train of waves. The most frequent causes of tsunamis are shallow underwater earthquakes and submarine landslides, but tsunamis can also be caused by underwater volcanic explosions, oceanic meteor impacts, and even underwater nuclear explosions. Tsunamis are characterized by their length, speed, low period, and low observable amplitude: the waves can be up to 200 km (125 mi) long from one crest to the next, they travel in the deep ocean at speeds of up to 950 km/hr (600 mi/hr), and have periods of between 5 minutes and up to a few hours (with most tsunami periods ranging between 10 and 60 minutes). Their height in the open ocean is very small, a few meters at most, so they pass under ships and boats undetected (Garrison, 2002), but may pile up to heights of 30 m 000 ft) or more on entering shallow water along an exposed coast, where they can cause substantial damage. The highest elevation that the water reaches as it runs up on the land is referred to as wave runup, uprush, or inundation height (McCulloch, 1985; Synolakis et al., 2002). Inundation refers to the horizontal distance that a tsunami wave penetrates inland (Synolakis et al., 2002). Earthquake -generated tsunamis have been studied more extensively than any other type. Researchers have found that there is a correlation between the depth and size of the earthquake and the size of the associated tsunami: the larger the earthquake and the shallower its epicenter, the larger the resulting tsunami (Imamura, 1949; lida, 1963, as reported in McCulloch, 1985). The . size of the tsunami is also related to the volume of displaced sea floor (Iida, 1963). Given these Earth Consultants International Coastal Hazards Page 1-3 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • correlations, several researchers in the last decades have modeled tsunami runups for various areas along the Pacific Ocean, including in the western United States (Houston, 1980; Brandsma et al., 1978; Synolakis, 1987; Titov and Synolakis, 1998; and many others — refer to http://www.usc.edu/dept/tsunam is/tsupubs). Rogue waves are very high waves, as much as tens of meters high, but, compared to tsunamis, they are very short from one crest to the next, typically less than 2 km (1.25 mi) long. Rogue waves arise unexpectedly in the open ocean, and their generating mechanism is a source of controversy and active research. Some theories on rogue wave formation include: Strong currents that interact with existing swells making the swells much higher; A statistical aberration that occurs when a number of waves just happen to be in the same place at the same time, combining to make one big wave; The result of a storm in the ocean where the wind causes the water surface to be rough and choppy, creating very large waves. Rogue waves are unpredictable and therefore nearly impossible to plan for. Nevertheless, as described in Section 1.3.1 below, some high waves that have historically impacted the Orange County coastline may be best explained as rogue waves. if this is the case, rogue waves have the potential to impact the Newport Beach area in the future. 1.3.1 Notable Tsunamis and Rogue Waves in the Newport Beach Area In the Pacific Basin, most tsunamis originate in six principal regions, all of which have • prominent submarine trenches. Of the six regions, only two have produced major tsunami damage along the California coastline in historical times. These are the Aleutian (Gulf of Alaska) region and the region off Chile, in South America (CDMG, 1976). Southern California is generally protected from teletsunamis by the Channel Islands, which deflect east- and northeast -trending waves, and by Point Arguello, which deflects waves coming in from the continental area of Alaska (see Plate 1-1). Tsunamis generated by local earthquakes or landslides have historically posed only a minor, localized risk to southern California. However, the record also shows that the highest sea waves recorded in the southern California area were caused by a locally generated tsunami, the 1812 Santa Barbara event. Although the historical record for southern California is short, over 30 tsunamis have been recorded in southern California since the early 1800s (see Table 1-1). Given that instrumented tidal measurements in southern California were first made in 1854, wave heights for pre-1854 events are estimated based on historical accounts. Most records are for the San Diego and Los Angeles areas, with only a few events actually mentioned in the Orange County area. Most of the recorded tsunamis produced only small waves between 0.15 and 0.3 m (0.5 — 1 ft) high that did not cause any damage, but six are known to have caused damage in the southern California area. Those six are marked in bold in Table 1-1, and are described further in the text below. Earth Consultants International Coastal Hazards Page 1-4 2003 • • San Miguel Santa Cruz low& Point Dume Santa Rosa al er e Xz rn h 277 Pe ins I Santa Barbara Azimuth 2591��= San Nicolas lllki San zimuth 264__ — _'s, Santa Catalina /N / / / / Wave Exposure Map Newport Beach, California EXPLANATION Areas exposed to distantly generated deep -water swell activity Zones of island interference creating shadows to incoming wave energy �i Approximate azimuth in degrees, �i read clockwise from true north City of Newport Beach and sphere of influence boundaries Scale: 1:1,000,000 10 0 10 20 30 Miles 20 0 20 40 60 Kilometers Base Map: USGS 10- and 30-m Digital Elevation Models Source:US Army Corps of Engineers, 1993 Earth Consultants International Project Number: 2112 Date: July, 2003 Plate 1-1 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Table 1-1: Historical Tsunami Record for Southern California - 1812 to Present (Tsunamis that caused damage in southern California are in bold) • Date Source Wave Height December,1812 Southern California; earthquake or Santa Barbara: -2-3 m (6.6-9.8 ft); landslide in Santa Barbara Channel? Ventura: -2-3 m (6.6-9.8 ft) November, 1853 Kurils Islands Unknown; possibly observed in San Diego May, 1854 Southern California; possibly same Unknown; observed in San Diego as July or December events July, 1854 Unknown; possible meteorological San Diego: -0.3 m (-1 ft) origin December 23, 1854 Japan San Diego: < 0.1 m (0.3 ft) December 24, 1854 Japan San Diego: 0.1 m (0.3 ft) July, 1855 Southern California; possible Unknown; large waves reported at offshore landslide caused by Point San Juan earthquake in Los An eles April, 1868 Hawaii San Diego: 0.1 m (0.3 ft) August, 1868 Chile San Diego: 0.3 - 0.8 m (0.6-2.6 ft); San Pedro: 1.8 m (5.9 ft) Wilmington: 1.8 m (5.9 ft) August, 1872 Aleutian Islands San Diego: < 0.1 m (0.3 ft) May, 1877 Chile San Pedro: 1 m (3.3 ft); Wilmington: I m (3.3 ft); Gaviota: 3.7 m (12.1 ft) August, 1879 Southern California; possible Unknown; tsunami reported at Santa undersea landslide caused by Monica earthquake in San Fernando area December, 1899 Southern California; Unknown; large wave reported Underwater landslide generated by along southern California coast earthquake in San Jacinto area? February, 1902 El Salvador -Guatemala Unknown; large wave ieported in San Diego January, 1906 Ecuador Unknown; reported in San Diego August, 1906 Chile San Diego: 0.1 m (0.3 ft) May, 1917 South Pacific Unknown; large waves reported in La Jolla June, 1917 South Pacific Unknown, reported in San Diego April, 1919 South Pacific Unknown; reported in San Diego November, 1922 Chile San Diego: 0.2 m (0.7 ft) February, 1923 Kamchatka San Diego: 0.2 m (0.7 ft) October, 1925 Unknown; possible meteorological Long Beach: 0.34 m (0.1 ft) origin or submarine volcanic event January,1927 Southern California; possible Unknown; large waves reported submarine landslide caused by along southern California coast earthquake in imperial Valle November, 1927 Central and southern California; La Jolla: 0.2 - 0.3 m (0.7-1 ft); offshore earthquake off Point Surf 1.8 m (5.9 ft) Arguello, possibly on the Hos ri fault Port San Luis: 1.5 m (4.9 ft) June, 1928 Southern Mexico La Jolla: < 0.1 m (0.3 ft) • Earth Consultants International Coastal Hazards Page 1-6 2003 0 • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Date Source Wave Height August,1930 Southern California; offshore earthquake in Santa Monica Bay Santa Monica: 0.6 m (1.9 ft) March, 1933 Japan Los Angeles: 0.2 in (0.7 ft); Santa Monica < 2.0 m (6.6 ft) March, 1933 Southern California; Long Beach Earthquake Long Beach: 0.1 m? (0.3 ft) August,1934 Unknown; possibly caused by earthquake near Balboa, or of meteorological origin (rogue waves?) Newport Beach: 3 to rise (9.8 ft); 9.12 m (30 -39 ft) waves April, 1943 Chile San Diego: 0.1 m (0.3 ft) December, 1944 Japan San Diego: < 0.1 m (0.3 ft) April, 1946 Aleutian Islands Avila: 1.2 m (3A ft) March,1957 Aleutian Islands San Diego: 0.2 -1.0 m (0.7--3.3 ft) May, 1960 Chile Santa Monica:1.4 m (4.6 ft) May, 1964 Gulf of Alaska Santa Monica:1.0 m (3.3 ft) February, 1965 Aleutian Islands Santa Monica: 0.08 m (0.3 It) May, 1968 Japan Santa Monica: 0.2 m (0.7 ft); Long Beach: 0.1 m (0.3 ft) May, 1971 South Pacific Los Angeles: 0.05 in (0.2 ft) November, 1975 Hawaii La Jolla: 0.1 m (0.3 ft) June, 1977 South Pacific Los Angeles: 0.05 m (0.2 ft); Long Beach: 0.12 m (0.4 ft) Source: Compiled from Lander and Lockridge (1989) and McCulloch (1985) 1.3.1.1 Santa Barbara Tsunami of 1812 A strong earthquake in the Santa Barbara area on December 2V, 1812 produced a tsunami that caused damage in Santa Barbara and Ventura counties and was reported along the coast of southern California. However, the tsunami of 1812 occurred before the Newport Beach area was settled, so there are no data specific to Newport Beach for this event. The most likely source for the earthquake is a fault zone in the Santa Barbara Channel, although onshore faults east of Santa Barbara cannot be ruled out. While some historical accounts suggest the tsunami produced a maximum one -mile runup and wave heights of 15 m (49 ft) at Gaviota, 9 to 10.5 m (29.5 - 34.5 ft) at Santa Barbara and 3.5 m (11.4 ft) at Ventura, contemporary records from the missions at Santa Barbara and Ventura do not mention tsunami runup or damage to nearby coastal communities (Lander and Lockridge, 1989). The mission records describe only a disturbed ocean and fear of tsunami, suggesting that the accounts of high waves, most of which were recorded years after the event, may have been exaggerated (Lander and Lockridge, 1989). For example, an account of "an old trader" printed in the San Francisco Bulletin 52 years after 1812, reported a 1-mile runup in Gaviota. From this account, a 15 m (49 ft) wave height was derived using topographic maps. Accounts collected by Trask (1856), 44 years after the event, report that waves damaged the lower part of the town of Santa Barbara, half a mile inland. Trask (1856) also recorded reports of a ship damaged by a tsunami wave near San Buenaventura (present day Ventura). This may be the same vessel reported by Los Angeles Star in 1857 to have been Earth Consultants International Coastal Hazards Page 1-7 . 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • swept up a canyon at El Refugio Bay, near Gaviota. A third -hand account of tsunami damage to the mission in Ventura, located 4.5 m (14.8 ft) above sea level, is not corroborated by the mission records (Grauzinis et al., unpublished report). Grauzinis et al. (unpublished, based on data from Soloviev and Go, 1975; McCulloch, 1985; Marine Advisors, 1965; Pda et al., 1967; Wood, 1916; Heck, 1947; Toppozada et al., 1981), conclude that the most reliable historical data support a tsunami height of less than 3 m (9.8 ft) at Santa Barbara and Ventura, 3.5 m (11.4 ft) at El Refugio, and lower elsewhere in southern California. This is roughly consistent with analysis of predicted tidal data for the region by Long (1988) who suggests a wave height of 2 m (6.6 ft) at Santa Barbara and Ventura. 1.3.1.2 Tsunami of January 1927 A magnitude 5.7 earthquake followed by several aftershocks occurred in the Imperial Valley, at the border between the United States and Mexico, on January 1, 1927. According to Montandon (1928), sea waves in San Pedro destroyed a seawall or embankment causing about three million dollars in damage (Lander and Lockridge, 1989). However, since the Imperial Valley is far from the coast, and the earthquake was moderate in size, it is doubtful that these two events are related, unless the earthquake triggered a submarine landslide. 1.3.1.3 Possible Tsunami of 1934 On August 21, 1934 large destructive waves were reported along the coast of southern California from Malibu to Laguna Beach. The true source of the waves is not known, however several causative events have been suggested. Although official records show no • large earthquakes in the area on the day of the waves, a small, magnitude 3 tremor was reported in the Balboa region before the waves struck. Submarine landsliding, volcanic activity, and unusual meteorological conditions (rogue waves?) have also been suggested as possible explanations for the waves. A runup of 270 m (886 ft) inland, 3 m (9.8 ft) above mean high tide level was recorded at Newport Beach, which flooded part of the City to a depth of one meter (3.3 ft). Four people were injured near the channel entrance to Newport Bay, at the western pier. Many houses were destroyed, including a two-story home in Balboa that was detached from its foundation. Part of the pavement on Balboa Peninsula was washed away, temporarily isolating the residents of this area from the mainland. Thousands of tons of debris were tossed onshore. The waves also flooded a moorage in Balboa Island and collapsed part of the breakwater in Long Beach (Lander and Lockridge, 1989). 1.3.1.4 Aleutian Island Tsunami of 1957 A magnitude 8.3 earthquake in the Aleutian Islands on March 9, 1957 generated a small tsunami in the San Diego area that damaged two ships in San Diego Harbor and caused minor damage at La Jolla (McMulloch, 1985; lida et al., 1967; Salsman, 1959; Joy, 1968). A wave height of up to one meter (3.3 ft) was reported at Shelter Island, off the San Diego coast, although the tide gauge there recorded only a 0.2 m (0.7 ft) wave. No reports of damage were recorded in the City of Newport Beach. 1.3.1.5 Chilean Tsunami of 1960 • On May 22, 1960, a moment magnitude 9.4 earthquake off the coast of Chile produced a tsunami that damaged coastal communities in southern California between Santa Barbara Earth Consultants International Coastal Hazards Page 1-8 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • and San Diego. A wave height of 1.4 m (4.6 ft) was recorded in Santa Monica and the tidal gauge in San Diego was carried away by the tsunami waves (Lander and Lockridge, 1989). Significant damage was recorded in the Los Angeles and Long Beach Harbors, where 30 small craft were sunk and over 300 were set adrift. Over 340 boat slips, valued at $300,000, were also damaged in the area. At Santa Monica, eight small boats were swept away and a runup of 91 m (300 ft) flooded a parking lot along the Pacific Coast Highway. Damage of $20,000 was reported in the Santa Barbara area. At San Diego, two passenger ferries were knocked off course by the waves; the first ferry was pushed against a dock in Coronado, destroying 80 m (260 ft) of the dock, and the second was rammed into a flotilla of anchored destroyers. The waves also rammed a 100-ton dredge into the Mission Bay Bridge, knocking out a 21 m (70 ft) section and sinking a barge at Seaforth Landing (Lander and Lockridge, 1989; lida et al., 1967; Talley and Cloud, 1962; Joy, 1968). LJ • 1.3.1.6 Good Friday Earthquake Tsunami of 1964 On March 28, 1964 a moment magnitude 9.2 earthquake in the Gulf of Alaska produced the largest and most damaging tsunami to ever hit the West Coast. The tsunami killed 16 people in northern California and Oregon and caused $8,000,000 in damage in California. Although damage was primarily focused in coastal areas north of San Francisco, southern California experienced hundreds of thousands of dollars in losses. A wave height of 1 m (3.3 ft) was recorded in Santa Monica. in Los Angeles Harbor, the wave damaged six small -boat slips, pilings, and the Union Oil Company fuel dock. It also scoured the harbor sides, causing, all tolled, $175,000 to $275,000 in damage. The tsunami also destroyed eight docks in the Long Beach Harbor at a loss of $100,000 (Spaeth and Berkman, 1972). Minor damage was also reported elsewhere along the southern California coast. 1.3.2 Tsunami Scenarios for Newport Beach Because of the substantial increase in population in the last century and extensive development along the world's coastlines, a large percentage of the Earth's inhabitants live near the ocean. As a result, the risk of loss of life and property damage due to tsunamis has increased substantially. In fact, worldwide, tsunamis have been responsible for over 4,000 human deaths in the past decade alone (Synolakis et al., 2002). McCarthy et al. (1993) reviewed the historical tsunami record for California and suggested that the tsunami hazard in the southern California region from the Palos Verdes Peninsula south to San Diego, is moderate. However, as discussed previously, the southern California historical record is very short. Given that the recurrence interval for many of the faults in the world is in the order of hundreds to thousands of years, it is possible that southern California has been impacted by teletsunamis for which we have no record. More significantly, there are several active faults immediately offshore of the southern California area, and any of these could generate a future earthquake that could have a tsunami associated with it. Finally, several submarine landslides and landslide -susceptible areas have been mapped offshore, within 3.5 to 14 km of the coastline (Field and Edwards, 1980; McCulloch, 1985; Clarke et al., 1985). Synolakis et al. (1997) reviewed the McCarthy et al. (1993) study and other data, and concluded that not only do early, pre- 1980 methods give tsunami runup results that are more than 50 percent lower than what current inundation models predict, but that there is a need to model near -shore tsunami events. For the Orange County coastline particularly, near -shore tsunamis should be Earth Consultants International Coastal Hazards 2003 Page 1-9 -71 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA is would worst -case scenarios, as these have the potential to cause high runups that would impact the coastline with almost no warning. Having recognized the potential hazard, the next step is to quantify it so it can be managed appropriately. Although the record of tsunamis impacting the California coast goes back only to 1812, there are sufficient data from which mathematical models of tsunami runup for the California coast can be developed. Houston and Garcia looked at the worldwide, long-term historical data, and combined it with mathematical models to estimate the predicted, distantly generated, 100-year and 500-year probability tsunami runup elevations for the west coast of the United States (Garcia and Houston, 1975; Houston and Garcia, 1974; 1978; Houston et al., 1975; Houston, 1980; as presented in McCulloch, 1985). These predictions are used by the Federal Insurance Administration to calculate flood - insurance rates, thus the 100- and 500-year terms risk levels selected, similar to storm flooding. As with flooding, the 100- and 500-year designations do not mean that these tsunamis occur only once every 100 or 500 years, but rather, these terms describe the tsunami that has a 1 percent (for 100-year) or 0.2 percent (for 500-year) probability of occurring in any one year. The 100-year and 500-year tsunami runup elevations are thought to have the potential to cause significant damage to harbors and upland areas, while smaller 50-year events may cause damage to boats and harbor facilities, but the onshore damage will be restricted to very low-lying areas. Smaller than 50-year tsunamis may still cause minor damage to unprotected boats and harbor facilities (CDMG, 1976). The 100-year (R100) and 500-year (R500) teletsunami runup heights predicted for Newport • Beach are 1.49 and 1.98 m (4.9 and 6.5 ft), respectively (Houston, 1980, based on Figure 208 in McCulloch, 1985). The predicted tsunami runup heights by Houston 0980) were used in this report to prepare maps showing tsunami inundation zones for Newport Beach. However, for various reasons, these values are to be used only as a guide to quantify the risk of distantly generated tsunamis on the California coastline. Houston (1980) did not have the technology available to quantify the effect that estuaries, the offshore zone where water is 5 to 10 meters deep, and the shoreline have on tsunami runup (C. Synolakis, personal communication, 2002). Furthermore, Houston's (1980) predicted heights are based on mean sea level elevation data, and therefore do not show the maximum credible heights that are possible if a tsunami coincides with peak high tide, or with storm -induced high water. To account for this, several scenarios were prepared herein to show the estimated inundation areas expected for Newport Beach under different sea level conditions. These scenarios are simple, linear, first -order assessments of inundation of all land areas at an elevation equal to or below the elevation of the water column calculated for each scenario, without taking into consideration the shallow bathymetry and near -shore topography, which are known to have a significant impact on tsunami inundation. As a result, these scenarios should be used for general planning purposes only, until the more detailed tsunami inundation maps for this area (discussed below) become available. The University of Southern California Tsunami Research Group, under the direction of Professor Costas Synolakis, is currently preparing tsunami inundation models on behalf of • the Office of Emergency Services for the northern Orange County area. Unfortunately, the maps that they are preparing will not address tsunami inundation in the Newport Bay area Earth Consultants International Coastal Hazards Page 1-10 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • because detailed modeling of the inundation depths (bathymetry) and currents in the bay is required, and the State budget does not allow for this level of detail (C. Synolakis, personal communication, 2002). This research group is also modeling potential locally generated tsunamis caused by either offshore faulting or submarine landsliding. Their initial models indicate that these locally generated tsunamis are a concern: earthquakes in the Santa Barbara Channel could generate a 2 m (6.6 ft) runup, while an earthquake -induced submarine landslide could generate a runup of as much as 20 m (66 ft) (Borrero et al., 2001). Their north Orange County models will include locally generated tsunamis caused by both offshore faulting or landsliding, but again, they are excluding Newport Bay. 1.3.2.1 Scenario 1: Tsunami Inundation at Mean Sea Level The tsunami inundation maps prepared for this study are based on several sea water levels that are specific to each area, and often legally defined. Mean sea level (MSL) is defined as the average height of the ocean surface for all tide stages, measured over a 19-year period based on hourly height observations made on an open coast, or in adjacent waters having free access to the sea (Bates and Jackson, 1987). Mean sea level is adopted as the datum plane or zero elevation for a local or regional area. The City of Newport Beach has defined the sea level datum of 1929 (referred to as the National Geodetic Vertical Datum of 1929 — NVGD29) established by the United States Coast and Geodetic Survey, as the official datum plane of the City (City Ordinance No. 994). All other water levels and topographic elevation points in the City are measured relative to this datum. The NGVD29 system, however, has fallen in disuse, and other jurisdictions, such as the County of Orange, now use the NAVD88 system, which in this area is on average 2.37 feet higher than the • NGVD29 datum. The maps presented herein are based on the City's current NGVD29 datum. These can be expected to change in the future when, and if the City adopts the NAVD88 system. The mean sea level elevation at Newport Beach is shown graphically on Plate 1-2. 0 Earth Consultants International Coastal Hazards Page 1-11 2003 • • • , i y �ll , 'Z i n 4rff • I� L\n.'..�..• 41a I `1 - NOTES This map is intended for general land use planning only. Information on this map Is not sufficient to serve as a subslaNe for detailed geologic investigations of individual sites, nor does it satisti the evaluation requiremerts set forth in geologic hazard regulations. Earth consultants International (ECI) makes no repfesentatirms or warranties regarding the accuracy of the data from which these maps were derived. ECI shall not be liable under any circumstances for any direct, im irent, special, incidental, or consequential damages with respect to any claim by any user or third party on account of, or arising from. the use of this map. �,, r rlIle I �i Mean Sea Level Newport Beach, California EXPLANATION Mean Sea Level Newport Beach City Boundary Sphere of Influence Scale: 1:60,000 0.5 0 0.5 1 1.5 Miles 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from Sure! MAPS RASTER Source: USGS 10-m Digital Elevation Model m rV,N Po Earth ConsultantsAl�-—lntematiorial Cu o' � ) $ Project Number: 2112 r+ Date: July, 2003 Plate 1-2 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Plate 1-3 shows the predicted tsunami inundation areas for Newport Beach if the predicted 100- and 500-year tsunami runup heights (4.9 and 6.5 feet, respectively) are superimposed on the mean sea level. Plate 1-3 shows that Newport Bay and most of the harbor would be inundated, with the potential to damage small vessels and docks. Some of the properties adjacent to the Bay would also be impacted, especially the northwestern section of Balboa Island, which is predicted to be inundated. The water level in Upper Newport Bay is anticipated to rise some, but the data available are insufficient to quantify the hazard in this area. 1.3.2.2 Scenario 2: Tsunami inundation at Mean High Water Mean High Water (MHW) is referred to as the "average height of all the high waters recorded at a given place over a 19-year period or computed equivalent period" (Bates and Jackson, 1987). The MHW can often be recognized by the upper line of debris on the beach. For Newport Beach, the calculated MHW is 0.78 m (2.57 ft). Plate 1-4 illustrates the inundation zone for a tsunami occurring at high tide. Most of the harbor area, including the inland, developed portion of the Balboa Peninsula, Balboa Island, and Upper Newport Bay could be inundated during such an event. Near -shore sections of Lido Isle and Linda Isle would also be impacted, and Lido Isle would be cut off from the mainland due to flooding along Newport Boulevard and 32"d Street. This scenario is expected to cause considerable damage to homes in the low-lying areas, and to all moored boats. 1.3.2.3 Scenario 3: Tsunami Inundation at Extreme High Tide A tsunami occurring during extreme high tide would represent the worst -case scenario for • teletsunamis. Thus we modeled the 100- and 500-year wave runup on top of the highest recorded tide in the area of 2.66 m (8.74 ft), measured at station 9410580 on January 28, 1983 (NOAA/NOS, 2002). In this model, a significant portion of Newport Harbor and the low-lying areas south of Highway 1 would be inundated by both the 100- and 500-year wave runups (see Plate 1-5). The 100-year event shows that except for a small sliver of Lido Isle, the entire Newport Bay area would flood. Flooding is also anticipated in the area where Newport Dunes Resort is located. In the 500-year event, all of Lido Isle is expected to flood. The probability of a tsunami occurring during extreme high tide is highly improbable. However, these tsunami runups are possible if a tsunami occurs immediately offshore of Newport Beach, whether as a result of faulting or landsliding. Therefore, Plate 1-5 illustrates all of the areas that could benefit from evacuation plans and routes, as well as warning systems. 18 Earth Consultants International Coastal Hazards Page 1-13 2003 • • C� eeT +. a S \ 1 \, p r NOTES This map is intended for general land use planning only. Information on this map is not suRcient to serve as a substitute for detailed geologic investigations of individual sites, nor does it satisfy the evaluation requirements set forth In geologic nazarc regulations. Earth Consultants International (ECI) makes no representations or warranties regarding the accuracy of the data from which these maps were derlved. ECI shalt not be liable under any circumstances for any direct, indirect, special, incidental, or consequential damages with respect to any claim by any user or Thad parry on account of, or arising from, the use of this map. Scenario 1: Tsunami Inundation at Mean Sea Level Newport Beach, California EXPLANATION Tsunami Hazard Zones 100-year Zone (Inundation Elevation = 4.9 feet) 500-year Zone (Inundation Elevation = 6.5 feet) Zone of Minimal but Potential Tsunami Inundation Newport Beach City Boundary Sphere of Influence Tsunami Inundation Elevations. Mean Sea Level +Tsunami Height (100-year = 4.9 feet: 500-year = 6.5 feet) Scale: 1:60,000 0.5 0 0.5 1 1.5 Miles I 0 1 2 3 Kilometers Base Map: USGS Topographic Map from Sure!MAPS RASTER Source: Houston,1980, USGS 10-m Digital Elevation Model Earth Consultants International — Project Number: 2112 Date: July, 2D03 „x> Plate 1-3 • • • NOTES This map is intended for general land use planning only. Information on this map is not sufficient to serve as a substitute for derailed geologic investigations of Individual sitos, nor does it satisfy the evaluatlon requirements set forth In geologic hazard regulations. Earth Consultants International (ECI) makes na representaticns or warranties regarding the accuracy of line date from which These maps were derived. ECI shall not be liable under any circumstances for any direct, indirect, special, Incidental, or consequential damages with respect to any claim by any user or third parry on account of, or arising from, the use of this map. i T J ry / y Scenario 2: Tsunami Inundation at Mean Higher High Water Newport Beach, California EXPLANATION Tsunami Hazard Zones 100-year Zone (Inundation Elevation = 7.47 feet) 500-year Zone (Inundation Elevation = 9.07 feet) Newport Beach City Boundary Sphere of Influence Tsunami Inundation Elevations: Mean Higher Hi Water (2.57 feet)+Tsunami Height (100-year = 4.9 feet; 500-year = 6.5 feet) Scale: 1:60,000 0.5 0 0.5 1 1.5 Miles 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from Sure!MAPS RASTER Source: Houston,1980, USGS 10-m Digital Elevation Model Earth „t> �` Consultants International Project Number: 2112 Date: July, 2003 Plate 1-4 C lJ i r I � rJJJ y4 _ SEP P4v 1` ,. I •1 \ 19i s -r \ r- NOTES: • .aaaa` This map is intended for general land use planning only. Information on this map is not `\ -'--�- a Moiont to sil as a substitute for detailed geologic Invosligatione of individual sites, nor does If satisfy the evaluation requirements set forth in geologic hazard regulations. `• _-�- Earth Consultants lntemafioral(ECI) makes no representalicns or warranties regarding the accuracy of the dale from which these maps were derived. ECI shall not be liable ,'- under any circumstances for any direct, indirect, special, incidental, or consequential damages with respect to any claim by any user or third party on accounl of, or arising from, the use of this map. Scenario 3: Tsunami Inundation at Extreme High Tide Newport Beach, California EXPLANATION Tsunami Hazard Zones 100-year Zone (Inundation Elevation = 13.64 feet) 500-year Zone (Inundation Elevation = 15.24 feet) O Newport Beach City Boundary Sphere of Influence Tsunami Inundation Elevations: Highest Recorded Tide (8.74 feet) +Tsunami Height (100-year= 4.9 feet, 500-year = 6 5 feet) Scale: 1:60,000 0.5 0 0.5 1 1.5 Miles 1 0 1 2 3 Kilometers Base Map. USGS Topographic Map from Sure! MAPS RASTER Source: Houston,1980: USGS 10-m Digital Elevation Model Earlh Consultants International Project Number: 2112 Date: July, 2003 Plate 1-5 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 1.4 Storm Surges and Seiches Coastal flooding can occur as a result of several processes other than the tsunami and rogue waves discussed above. Two common coastal flooding processes include storm surges and Seiches. A storm surge is an abnormal rise in sea water level associated with hurricanes and other storms at sea. Surges result from strong on -shore winds and/or intense low-pressure cells associated with ocean storms. Water level is controlled by wind, atmospheric pressure, existing astronomical tide, waves and swell, local coastal topography and bathymetry, and the storm's proximity to the coast. Flooding of deltas and other low-lying coastal areas is exacerbated by the influence of tidal action, storm waves, and frequent channel shifts. Most often, destruction by storm surge is attributable to: Wave impact and the physical shock on objects associated with the passing of the wave front. The water may lift and carry objects to different locations. Direct impact of waves on fixed structures. This tends to cause most of the damage. Indirect impacts, such as flooding and the undermining of major infrastructure (such as highways and railroads). For example, unusually severe storms in June, July and August of 1920 caused extensive damage to the west jetty in Newport Beach. Tidal currents swept the sand from beneath the toes of the jetty's slopes, and the rocks sank into the ocean floor, which lowered the crest of the jetty so that two large gaps appeared in it at times of high tide. Storm -generated swells, especially when combined with tidal action also have the potential to cause damage. In the southern California • area, including Newport Beach, localized flooding and accelerated rates of coastal erosion have occurred when storms are combined with high tides. This occurred during the 1977-1978 storms, when the combination of high waves, local storm surges and high tides damaged several coastal structures in southern California. According to Walker et al. (1984), however, the piers and jetties at Newport Beach were not damaged by this storm. During the storms in 1988, the high water extended to the first row of houses behind the groin field at Newport Beach causing minor flood damage to these structures (Pipkin et al., 1992). A seiche is defined as a standing wave oscillation in an enclosed or semi -enclosed, shallow to moderately shallow water body or basin, such as lake, reservoir, bay or harbor. Seiches continue (in a pendulum fashion) after the cessation of the originating force, which can be tidal action, wind action, or a seismic event. Seiches are often described by the period of the waves (how quickly the waves repeat themselves), since the period will often determine whether or not adjoining structures will be damaged. The period of a seiche varies depending on the dimensions of the basin. Whether an earthquake will create seiches depends upon a number of earthquake -specific parameters, including the earthquake location (a distant earthquake is more likely to generate a seiche than a local earthquake), the style of fault rupture (e.g., dip -slip or strike -slip), and on the configuration (length, width and depth) of the basin. Amplitudes of seiche waves associated with earthquake ground motion are typically less than 0.5 m (1.6 feet high), although some have exceeded 2 m (6.6 ft). A seiche in Hebgen Reservoir, caused by an earthquake in 1959 near Yellowstone National Park, repeatedly overtopped the dam, causing considerable damage to the dam and its spillway (Stermitz, 1964). The 1964 Alaska Illft earthquake produced seiche waves 0.3 m (1 ft) high in the Grand Coulee Dam reservoir, and Earth Consultants International Coastal Hazards Page 1-17 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . seiches of similar magnitude in fourteen bodies of water in the state of Washington (McGarr and Vorhis, 1968). Upper Newport Bay, the harbor and some of the reservoirs in Newport Beach could be susceptible to seiches, however, due to the small surface area of Newport Bay and Upper Newport Bay, the probability that damaging seiches would develop in these bodies of water was considered low in the 1975 Newport Beach Safety Element, and no new information has been found to change that conclusion. Seiches in reservoirs will be discussed further in Chapter 4. 1.5 Hurricanes and Tropical Storms Tropical cyclones are great masses of warm, humid, rotating air that occur between 100 and 25° latitude on both sides of the equator. Large tropical cyclones, those with wind speeds greater than 119 km/hr (74 mi/hr), are referred to as hurricanes in the North Atlantic and the Eastern Pacific Oceans (Garrison, 2002). Hurricane season, the time of the year when most hurricanes are generated, runs from June to the end of November, with peak activity from mid -August to late October (http://hurricanes.noaa.gov). Most hurricanes that affect the southern California region are generated in the southern portion of the Gulf of California. Though hurricane -strength storms have not been reported in southern California, tropical storms, those with wind speeds less than 119 km/hr (74 mi/hr), have caused damage to southern California in the past. The main hazards associated with tropical cyclones, and especially hurricanes, are storm surge, high winds, heavy rain, flooding, and tornadoes. The greatest potential for loss of life related to a • hurricane for coastal communities is from the storm surge, which if combined with normal tides can increase the mean water level by 4.6 m (15 ft) or more (http://hurricanes.noaa.gov). Waves that high would breach or extend over the Balboa Peninsula and impact all development adjacent to the coastline, including areas along Corona del Mar and Crystal Cove. I• Tropical storm -force winds and waves are strong enough to be dangerous to those caught in them. Water weighs approximately 1,700 pounds per cubic yard; therefore, extended pounding by frequent waves can demolish any structure not designed to withstand such forces. Hurricane and tropical -force winds can easily destroy poorly constructed buildings and mobile homes. Debris such as signs, roofing material, and small items left outside become flying missiles in hurricanes. Extensive damage to trees, towers, underground utility lines (from uprooted trees), and fallen poles cause considerable disruption. High-rise buildings are also vulnerable to hurricane -force winds, particularly the upper floors, since wind speed tends to increase with height. It is not uncommon for high-rise buildings to suffer a great deal of damage, typically due to windows being blown out. Consequently, the areas around these buildings can be very dangerous. Widespread rainfall of 6 to 12 in (15 to 30 cm) is common during the landfall of a hurricane, frequently producing deadly and destructive floods. Such floods have been the primary cause of tropical cyclone -related fatalities over the past 30 years worldwide (http://hurricanes.noaa.gov). Hurricanes can also produce tornadoes that add to the storm's destructive power. In general, tornadoes associated with hurricanes are less intense than those that occur in the plains area of the United States. Interestingly, some hurricanes produce no tornadoes, while others produce multiple ones. Either way, the effects of tornadoes, added to the larger area of hurricane -force winds, can produce substantial damage (http://hurricanes.noaa.gov). Earth Consultants International Coastal Hazards Page 1-18 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Though no hurricane -strength storms have reportedly hit the Los Angeles basin area in modern times, damage from wave swell and weather related to hurricanes that develop in the Baja California area has been reported throughout southern California. Swells caused by offshore storms and hurricanes in Baja California can cause localized flooding and erosion of the southern California coastline. Only one tropical -strength storm has ever been recorded as actually hitting California (http://www.usatoday.com/weather/whhcalif.htm). Near the end of September 1939, a tropical storm with sustained winds of 80.5 km/hr (50 mi/hr) came ashore at Long Beach. The storm generated five inches of rain in the Los Angeles basin on September 25", and between 6 and 12 inches (15 and 30.5 cm) of rain in the surrounding mountains. In Newport Beach, this storm produced 30-foot high waves (as high as a three-story building) that tore away half of Newport Pier and destroyed most of Balboa Pier, damaged portions of the jetties, several homes and small vessels, and caused numerous drownings (P. Alford, personal communication, 2002). Other less severe but still significant storms that impacted the southern California coastline occurred during 1927, 1938-1939, 1941, 1969, 1977-1978, 1983, 1988 (Kuhn and Sheppard, 1984; Walker et al., 1984; Pipkin et al., 1992), and even more recently in 1995, and 1997-1998. Many of these wet winters have been associated with ENSO (El Nino Southern Oscillation) events. 1.6 Sea Level Rise 1.6.1 Sea Level Change The level of the oceans has always fluctuated with changes in global temperatures. During the last ice age, when global temperatures were 5°C (9°F) lower than today, much of the ocean's water was tied up in glaciers, sea level was as much as 130 meters (430 feet) lower than today (Oldale, 1985; Lajoie et al., 1991), and the California coast was 5 to 15 mi (8 to 25 km) farther offshore than its present position (Department of Boating and Waterways and State Coastal Conservancy, 2002). The last ice age ended approximately eighteen thousand years ago, and since then the world has been experiencing global warming - most of the ice caps have melted, most of the glaciers have retreated, and the sea level has risen. Until about 5,000 years ago, sea level rose rapidly at an average rate of nearly 0.4 in (1 cm) a year. Since then, sea levels have continued to rise but at a slower pace. We are currently in an interglacial period, meaning "between glacial" periods, and as a result, sea levels are relatively high. However, during the previous last major interglacial period (approximately 100,000 years ago), temperatures were about VC (2T warmer that today and sea level was approximately 6 meters (20 feet) higher than today (Mercer, 1970). The changes in sea level over the last about three hundred thousand years are shown on Figure 1-1. When discussing shorter periods of time, one must distinguish worldwide (eustatic) sea level rise from relative sea level rise, which includes land subsidence. Although climate impacts sea level worldwide, the rate of sea level rise relative to a particular coast has more practical importance and is all that current monitoring stations can measure. Because some coastal areas are sinking while others are rising, relative sea level rise in the United States varies from more than one meter (3 feet) per century in Louisiana and parts of California and Texas, to 30 centimeters (1 foot) per century along most of the Atlantic and Gulf Coasts, to a slight drop in much of the Pacific Northwest (Titus et al., 1991; Knuuti, 2002). Large variations can occur locally. For example, in San Francisco, the Presidio gauge near the entrance to the Golden Gate has measured a relative sea level rise of 1.41 mm/yr in the last nearly 150 years. Across the bay, however, the 60-year-long gauge Earth Consultants International Coastal Hazards Page 1-19 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • record at Alameda shows a relative mean sea level rise of only 0.89 mm/yr. Closer to home, in Los Angeles, the relative mean sea level trend for 77 years of record is 0.84 mm/yr, while in San Diego the 94-year-long record shows a linear trend in relative sea level rise of 2.15 mrn/yr (Knuuti, 2002, based on unpublished data by C. Zervas). For a comparison of the relative sea level rise measured at the San Francisco, Los Angeles, and San Diego gauges, refer to Figure 1-2. These numbers briefly show that quantifying sea level changes worldwide is not a simple task. Figure 1-1: Worldwide Sea Level Curve for the Last Three Hundred Thousand Years Using Current Sea Level as the Reference Point 100 m ? 50 >C a mo 0 J 8 > -50 U! m W -100 0 100 200 300 Time Before Present (in thousands of years) Figure 1-2: Historical Relative Sea Level Rise at • Three Locations along the Pacific Coast of the United States (San Francisco, Los Angeles and San Diego) 73M t San Francrs San (),go Tipp Los Angeles U., (San Franascol — uneof (San [leg ) C — t✓raal(Los Anpeles) ■jY•• 7100 ff J f At 1 a Moo UP 0 = 6900 K Year Linear Trends at each Location are shown by the Straight Lines Source: Based on data obtained at httpJ/www.nbi.ac.uk/psmsi/psmsl_individual_stations.html • Earth Consultants International Coastal Hazards Page 1-20 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 1.6.2 Effects of Sea Level Rise Global sea level trends, therefore, have generally been estimated by combining the trends at tidal stations around the world. These records suggest that during the last century, worldwide sea level has risen 10 to 25 cm (4 to 10 inches) (Peltier and Tushingham, 1989), much of which has been attributed to global warming (Meier, 1984). Although sea level rise by itself does not cause substantial changes in the landform, several processes associated with sea level rise can have dramatic effects on our environment. For example, a significant rise in sea level would inundate coastal wetlands and lowlands, and the increased surges and swells associated with this rise in sea level would accelerate coastal erosion and exacerbate coastal flooding, thereby threatening local structures and habitat. Other related processes include higher water tables, increased sea -water intrusion into fresh water aquifers, and increased salinity of rivers, bays, and aquifers (Titus et al., 1991). The warmer climate may also result in a much higher probability of extremely warm years with increased precipitation in some areas, and drought in other areas. It is clear that global changes in climate will occur, but the local impacts are still being debated. In fact, recent studies have moved away from the global doomsday predictions to predictions at the local scale. Much work yet needs to be done in this area. Previous studies suggest that a 1 m (-39 in) rise in sea level would generally cause beaches to erode 200 to 400 m (650 to 1,300 ft) along the California coast (Wilcoxen, 1986). Given that the width of the beaches in Newport Beach varies between 15 and 190 m (50 and 600 ft), a sea level rise of as little as 15 cm (6 in) could have a negative impact on the low lying areas around Newport Bay that are not protected by bulkheads and seawalls. Sea level rise • would also cause increased sea -cliff retreat in the southern portion of the City where the beaches are narrow, and the surf pounds at the base of the bluffs, eroding away the soft bedrock that forms the cliffs (see Sections 1.7.1 and 1.7.2). How long would it take for sea level to rise 15 cm (6 in) in Newport Beach at the current rate? Given that a long-term record of sea -level measurements is not available for the Newport Beach area, sea level rise in the City needs to be estimated from regional records. Using the San Diego and Los Angeles gauge records mentioned above, it could take anywhere between 70 and 180 years for sea level in Newport Beach to rise 15 cm, assuming that global warming is not exacerbated in the next decades. Obviously, local measurements of relative sea level change are necessary to better quantify these estimates and make more realistic predictions. 1.6.3 Potential Human Actions in Response to Sea Level Change Human response to sea level changes include: 1) no action, 2) use of barriers, such as levees, to protect the built areas, 3) raising the coastline by placing sand on the beach and raising the buildings and supporting infrastructure, and 4) retreat (Titus, 1990; Nordstrom, 2000). Problems resulting from the no -action option include loss of recreational beaches due to accelerated erosion, loss of bayside property through erosion and inundation of low-lying areas, and stranding of buildings and infrastructure on the beach. As residents move inland, there is increased competition for land and living space, and natural resources in the backbays become increasingly threatened. Eventually, abandonment of the barrier reefs or peninsulas, and islands in the bays could become necessary. This . option however, is not likely to happen in the near future in areas like Newport Beach, where there is a strong social, economic, and cultural need to maintain the integrity of the Earth Consultants International Coastal Hazards Page 1-21 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • beaches, harbors and islands, and there are economic resources available to implement other options. The second option involves construction of seawalls and other flood protection structures around the threatened areas. The most significant advantage of this option is that major institutional changes in land use are not required (Titus, 1990; Nordstrom, 2000). Lots, houses and roads would not have to be raised or moved. However, the increased water levels around the bulkheads, seawalls and other artificial structures would result in increased breaking wave energy, higher storm runup, and increased beach loss. Structures would have to be designed or improved to withstand these environmental assaults. Beaches could be maintained by artificial nourishment, but at a great cost and frequency. The third option is probably cost -prohibitive in most areas. This would require placing sand on the beach to raise the ground surface, and raising the buildings and supporting infrastructure. Borrowing the large volumes of sand required would no doubt trigger environmental issues that would prohibit implementation of this option. Even if this were accomplished at the local level, raising the beach could increase the likelihood of bayshore erosion (Titus, 1990). Retreat is the most environmentally sensitive option, but it involves new legislation that allows for land acquisition by public authorities, use of setback lines and prohibition of reconstruction after damage. The economic and social costs of land loss and • compensation issues make this option unpalatable to most; strong political and public opposition can be expected. In intensely developed, premium real estate areas like Newport Beach, implementation of this option is very unlikely. Nevertheless, if sea levels do rise, this may ultimately prove to be the most cost-effective option. 1.7 Coastal Erosion Assessment 1.7.1 Geomorphology of the Coastline As discussed in Section 1.1, in the last one hundred years, the Newport Beach coastline has been modified extensively by both natural processes and humans. The wide sandy beaches that we associate with West Newport Beach are actually the result of shoreline stabilization programs that began as early as the 1920s, and beach sand nourishment programs that began in earnest in the 1960s. The "natural" beaches that characterized the southern California coastline prior to significant anthropogenic intervention were narrow strips of dry beaches on a sand -starved coast (Department of Boating and Waterways and State Coastal Conservancy, 2002). These beaches would be unable to support the present- day demands for coastal access and recreation. In an undeveloped area, the availability of sand to replenish the beaches is dependent on floodwaters that bring sediment down from the mountains and into the littoral drift zone offshore. However, with the increase in dams and other flood control structures upstream, significantly less quantities of sediment reach the coast. Therefore, the sediments lost by natural near -shore processes are not being replaced. This is certainly the case in southern • California, where most of the major streams have been dammed, or are lined in concrete, significantly reducing their sediment load. In the Newport Beach area, sand was Earth Consultants International Coastal Hazards Page 1-22 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . historically delivered to the local beaches by the San Gabriel and Santa Ana Rivers, and to a limited extent, as a result of coastal bluff erosion. With the construction of dams and channelization of portions of the Santa Ana and San Gabriel Rivers, there was a substantial reduction in the volume of sediment reaching the coastline. Construction of harbors, jetties, and other coastal barriers further reduced the amount of sand moved by along- shore currents. By the early 1940s, beach erosion was particularly severe along the Surfside-Sunset and West Newport beaches. Beach nourishment operations were begun in 1945, with nearly 2.3 million cubic yards of sediment used to replenish the Surfside-Sunset shoreline between 1945 and 1956. Then, in 1964, the Corps, in cooperation with the State of California and the County of Orange began the Orange County Beach Erosion Control Project to mitigate erosion along that portion of the Orange County coastline between Surfside-Sunset and Newport Harbor. In Newport Beach, the project included beach nourishment and construction of the groin field (see Section 1.1). Approximately 495,000 cubic yards of sediment borrowed from the Santa Ana River and the Balboa Peninsula were placed on West Newport Beach in 1968. An additional 874,000 cubic yards were placed in 1970, and another 358,000 cubic yards were placed in 1973. In 1992, nearly 1.3 million cubic yards of beach -quality sediment were placed in a near -shore sand bar off the coast of Newport Beach. The sediment placed in 1970, 1973 and 1992 was taken from the Santa Ana River (Department of Boating and Waterways and State Coastal Conservancy, 2002). As a result of these beach nourishment and beach protection operations, since the early 1960s the beaches in the entire project area have increased in width at an average rate of 4.1 fUyr. The resultant wide -sloped • beaches provide a protective barrier to the homes and businesses near to and along the beach, in addition to increased area for recreational purposes. South of the channel entrance to Newport Bay, to the south of the beach nourishment project area, the coastline is defined by steep coastal bluffs with a narrow basal wavecut platform that is covered by a thin veneer of beach sand. The bluffs form steep cliffs, especially at points. The Newport Beach coastal bluffs consist of marine sandstone and siltstone of the Monterey Formation. The sandstone beds are resistant and cliff forming, while the siltstone beds are less resistant and form steep talus -covered slopes. The bedrock of the Monterey Formation is folded, and dips primarily to the east, away from the bluff face. Overlying the Monterey Formation are Pleistocene marine terrace deposits. These deposits are massive to crudely bedded, consist of medium to coarse sand with a trace of pebble -sized gravel, and are friable and locally loose. A resistant shell bed marks the base of the terrace deposits. At the base of the bluffs is a mantle of colluvium. It consists of angular, pebble- to boulder - size clasts of sandstone and siltstone. In some areas, this colluvial cover buries the bluffs almost to the top, and in some areas, the material is reworked and forms a low terrace with weak soil development. The colluvium is heavily vegetated and appears to protect the base of the cliffs against normal wave action. 1.7.2 Susceptibility of the Coastal Sediments to Erosion • As noted previously, Newport Beach has a variety of coastal features ranging from replenished beach sands in West Newport, to steep bluffs comprised of sandstone and Earth Consultants International Coastal Hazards Page 1-23 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • siltstone to the south of Corona del Mar. Significant coastal bluff retreat, bluff -top erosion, gullying, and beach erosion are occurring along the southern Newport shoreline, but the rates of erosion are dependent in great measure on the underlying geologic units. Plate 1-6 shows four distinct lithological (rock or sediment) zones along the shoreline, each of which responds differently to the weathering effects of water (including rain and waves), gravity and wind. The following section describes the inherent problems associated with each lithologic zone as it pertains to coastal erosion. It should be noted that during a field review of the coastal bluffs of Newport Beach, only one possible landslide or slump block was identified, approximately 1,400 feet north of Pelican Point. 1) Beach sands occur from south of the Santa Ana River to the north entrance to Newport channel. Some of these deposits support dune vegetation, especially the sands forming the Balboa and Newport beaches. When the dune vegetation is well established, erosion of these sediments is minimal. However, foot or vehicular traffic and the burrowing action of rodents can easily compromise the health of this vegetation cover, exposing the near -surface sediments to erosion. Sand is easily transported during storms and can erode quickly if up -drift sand sources are cut off. The narrow beaches south of the channel entrance are especially vulnerable to high waves caused by tsunamis or storm surge. Beach erosion may be a problem south of the channel entrance due to the impedance of sediment redistribution via longshore flow by seawalls and rocky bluffs to the north. The area north of the jetties is also • vulnerable to inundation due to low beach relief and erosion of coastal dunes. 2) The elevated 100,000-year old marine terrace deposits are prone to landslides along steep cuts (such as those along Highway 1) and are susceptible to significant erosion by stream incision, including rifling and gullying along bluff tops. Several streams are cutting through the coastal bluffs, forming steep narrow gorges and undermining the bluffs where they emerge along the coastline. The cap of marine terrace deposits overlying bedrock of the Monterey Formation (see Nos. 3 and 4 below) is heavily rilled along stream cuts and along the face of the bluffs; so it is retreating faster than the underlying bedrock. 3) The siltstone member of Monterey Formation is very fissile and fractured. Sliding and slumping of this unit appears to be the primary mechanism for current bluff retreat, with these processes occurring primarily along slopes that have been oversteepened by wave action (along rocky bluffs) or stream incisions. The sandstone member of the Monterey Formation is the most resistant bluff -forming unit in the area. This geologic unit is prone to landsliding or mass wasting where undercut by wave action, especially at rocky bluffs or points, failing primarily as large blocks. Several rocky bluffs along the coastline, including Pelican, Reef and Abalone Points are subject to strong wave action that undermines the cliffs in these areas. Bluffs between these points are armored against ordinary wave action by the mantle of colluvium that has accumulated at their base and been stabilized by vegetation. High • waves may remove this basal material from time to time, but there is no evidence (such Earth Consultants International Coastal Hazards Page 1-24 2003 • • • Newport ♦•\ Beach Pier '•\ Balboa l� Beach Pier \• West \♦ Jetty East \♦ Jetty NOTES: This map is intended for general land use planning only. Information on this map is not sufficient to serve as a substitute for detailed geologic investigations of individual ad", nor does 1 satisfy the evaluation requirements set forth In geologic hazard regulations - Earth Consultants International (ECI) makes no representations or warranties regarding the accuracy of the date from which these maps were derived. ECI shall not be liable under any circumstances for any direct, Indirect, special, Incidental, or consequential damages with respect to any claim by any user or third party on account of, or arising from, the use of this map. -'ref A A N I I ° r: Coastal Erosion Hazard Map Newport Beach, California EXPLANATION - Sandstone member of Monterey Formation; most resistant bluff -forming unit. Prone to landsliding or mass wasting where undercut by wave action, especially at points. Fails as large blocks. Siltstone member of Monterey formation; very fissile and fractured; tends to form an apron of talus at the base of slopes. A Pleistocene marine terrace deposits; prone to landsliding along steep cuts (i.e. Highway 1), and to erosion by rilling and gullying along blufftops. - Beach and eolian sand covering the gently sloping to level beaches. Continuously reworked by wave and wind action. Newport Beach City Boundary Sphere of Influence Scale: 1:60,000 0.5 0 0.5 1 1.5 Miles 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from SurelMAPS RASTER Mapping by Earth Consultants International Earth �-- Consultants Intemational Project Number: 2112 Date: July, 2003 Plate 1-6 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • as notches at the base of exposed cliffs) to suggest that undercutting of the bedrock is currently occurring in these areas. South of the City limits, in the Crystal Cove area, houses are built on the beach at the base of the coastal bluffs. This area is subject to mass wasting and/or Iandsliding. The potential for impact from tsunami runup or storm surge is great in this area. Small cliffs in Crystal Cove State Park are also being undermined by differential erosion of the siltstone bedrock (the lower 10 to 15 feet of the bluff), which has eroded back farther than the sandstone at the top of the bluff. The City of Newport Beach has regulations regarding development in bluff areas (Planned Community District Chapter 20.51). Grading, cutting and filling of natural bluff faces or bluff edges is prohibited in order to preserve the scenic value of bluff areas, except for the purpose of performing emergency repairs, or for the installation of erosion preventive devices or other measures necessary to assure the stability of the bluffs. The City ordinance also states that a property line cannot be located closer than 40 feet from the edge of the bluffs. In addition, no part of a proposed development can be located closer than 20 feet to the bluffside property line. These regulations are applied to all new developments in the City, but are not retroactive. Therefore, in some areas, existing, older developments are closer to the edge of the bluff than the current regulations allow (see Figure 1-3). A concern with urbanization of the bluff areas is that the bluff -forming materials become saturated when shallow ground water rises in response to the increased watering of lawns, • generally in an attempt to grow non-native vegetation. Agricultural irrigation, septic tanks and leach lines also contribute to the increased water content of these deposits. This over - watering increases the weight of the sediments, lubricates any joints or fractures that can act as planes of weakness, and increases the chemical dissolution of the underling rocks. All of these processes can contribute to slope instability along the bluffs (see Figure 1-3). Figure 1-3: Near -Bluff Development and Erosion of Slopes due to Increased Water Application • Earth Consultants International Coastal Hazards Page 1-26 2003 • • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA 1.7.3 Artificial Coastal Protection The use of artificial coastal protection structures was favored 30 to 50 years ago, when the groin field in West Newport was constructed. Other structures intended to protect the coast, such as concrete and wooden seawalls and bulkheads, riprap and rock aprons are located in and around Newport Harbor and the adjacent shoreline. However, it has been long observed that where such protective structures extend seaward beyond adjacent unprotected lots, immediate erosion and notching may occur down drift (Kuhn and Shepard, 1985), especially during large storms and periods of high tide. As beach sand levels fall, storm waves tend to converge on projecting structures (i.e. groins) and the waves refract toward unprotected areas of the beach. Therefore given that improperly located artificial protective devices can have negative impacts that far outweigh their benefits, beach nourishment has emerged as the preferred method of shoreline stabilization in recent decades. Structures built perpendicular to the shoreline tend to slow the long -shore drift of sediments and thus starve the down -drift area of beach -nourishing sediments. This is seen on a larger scale at the Newport Beach jetty area. The area east of the jetties has an erosional notch due to the blockage of littoral drift from the north. On a smaller scale, groins can have the same effect. In the case of West Newport Beach, eight rock groins were installed in the late 1960s and early 1970s to help maintain the beach (see Table 1-2, Plate 1-6 and Figure 1-4). The effect of this groin field on the width of the beach is readily apparent — the beach on the northwest side of the groin field is wider than the beach where the groins are located. Southeast of the groin field, sand is being trapped by the west jetty, which stabilizes the Balboa Peninsula. The effect of these structures is complemented and augmented by regular beach sand replenishment. The protection of the beaches provides more than just a wider beach for recreational purposes and real-estate development; it serves as a buffer zone that provides protection from tsunami runup or storm surges, especially in areas where there are no dune deposits in front of residential or commercial development Table 1-2: Existing Rock Groins along Newport Beach (described from North to South; refer to Plate 1-6 for their location) Len in Feet Width in Feet 1 340 45 2 185 45 3 200 45 4 300 45 5 335 45 6 370 45 7 390 45 8 445 45 Erosion stabilizations measures that have been implemented in the Corona Del Mar area include concrete covering on one unstable slope, vegetation along the tops and bases of bluffs, boulders at the base of bluffs, where no colluvial cover exists, and channelization of the streams to prevent further downcutting of the terrace and bedrock units. • Earth Consultants International Coastal Hazards Page 1-27 2003 • CI HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA South of the City, Crystal Cove State Park has implemented an aggressive planting program aimed at stabilizing coastal bluffs. This includes planting vegetation on colluvium at the base of bluffs, on highly erosive terrace deposits, on blufftops, and within the channels that have cut into the bluffs. Figure 1-4: Artificial Coastal Protection; Rock Groin along Newport Beach 1.8 Policy Recommendations for Reducing Coastal Hazards Newport Beach is world famous for the quality of its sand beaches. Its citizens have built a lifestyle around beach access, and visitors come from all over southern California and the world to participate in that beach experience. With continued pressures from normal beach erosion, and with those pressures increased as sea level rises, the challenge to maintain the public beaches will ultimately run into the challenge to maintain the private properties that surround the beaches. In short, Newport Beach must develop long-range strategies to protect and maintain its beaches, or it will lose them. Newport Beach is also susceptible to low -probability but high -risk events like tsunamis and earthquakes. Ignoring these issues will not make them go away or reduce their probability of occurrence. Therefore, it is to the City's benefit to develop tsunami preparedness policies and programs that can be implemented to reduce these hazards, and having a post -tsunami recovery plan that can be implemented "off -the -shelf" immediately after the disaster occurs. 1.8.1 Tsunamis I.8.I.1 Hazard Assessment The Channel Islands and Point Arguello protect Newport Beach from most distantly generated tsunamis (teletsunamis) spawned in the Pacific Ocean, except for those generated in the Aleutian Islands, off the coast of Chile, and possibly off the coast of Central America. Nevertheless, since the early 1800s, more than 30 tsunamis have been recorded in southern California, and at least six of these caused damage in the area, • Earth Consultants International Coastal Hazards Page 1-28 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • although not necessarily in Newport Beach. Tsunamis generated in the Alaskan region take approximately 6 hours to make it to the southern California area, while tsunamis generated off the Chilean coast take 12 to 15 hours to reach southern California. Given those time frames, coastal communities in southern California can receive adequate warning, allowing them to implement evacuation procedures. Alternatively, very little warning time, if any, can be expected from locally generated tsunamis. Locally generated tsunamis caused by offshore faulting or landsliding (including earthquake -induced landsliding) immediately offshore from Newport Beach are possible, and these tsunamis have the potential to be worst -case scenarios for the coastal communities in Orange County. Modeling off the Santa Barbara coast suggests that locally generated tsunamis can cause waves between 2 and 20 m (6 to 60 feet) high, and that these could impact the coastline with almost no warning, within minutes of the causative earthquake or slump. 1.8.1.2 Hazard Mitigation As local and distant tsunami inundation maps for the local coastal communities are developed using internationally accepted mathematical models, the City of Newport Beach should review and adopt them. These maps should be GIS-based so they can be easily maintained and edited as local land uses change. Inundation (flooding) maps are useful because they provide all stakeholders with the information needed to make educated decisions about the risk of living and working in potential tsunami runup inundation areas. The maps presented herein provide a preliminary assessment of the tsunami hazard in Newport Beach, but these emphasize the hazard from distantly generated sources rather than the potentially more damaging local tsunami sources. The inundation models show • that the low-lying areas around the harbor, including the Balboa Peninsula, Newport Bay, Balboa Island, and to some extent Lido Isle, can be impacted by tsunami runup. As a result of tsunami inundation, these areas would be cut off from the rest of the mainland, so warning systems and evacuation plans for these areas should be developed and implemented. Residents in these areas need to be especially aware that an earthquake, even a distant one, has the potential to trigger offshore submarine landslides that could cause a local tsunami that would impact the coastline with little warning. Educational programs that emphasize evacuation of low-lying areas immediately after an earthquake is felt, in response to an unusual retreat of the ocean past the low tide mark, or in response to unusual seiching of the water surface, should help reduce the loss of life. This is especially true if individuals act upon these lessons without waiting for or requiring an official notification to evacuate, which might come in too late if the tsunami is generated locally. Regardless of the comments above, an early warning system for local tsunamis and an emergency plan to evacuate residents should be prepared. Given the need to evacuate low-lying areas as quickly as possible, exit routes to higher ground should be clearly posted. To summarize, mitigation measures that can be implemented to reduce the hazard of tsunamis in the Newport Beach area include: Develop workable response plans that the City's emergency services can adopt immediately for evacuation in the case of a tsunami warning. • Deploy a system of tsunami detection and early warning systems. This can be accomplished through existing systems and agencies, but planning and emergency Earth Consultants International Coastal Hazards Page 1-29 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • personnel need to be aware of them and have an action plan to follow in such an emergency. Place tsunami evacuation signs in threatened coastal areas. Evacuation routes off of the peninsula and islands in the Bay should be clearly posted. An evacuation route traffic monitoring system that provides real-time information on the traffic flow at critical roadways should be considered. Continue projects like the Surfside-Sunset/West Newport Beach Replenishment program to maintain beach width. Wide beaches provide critical protection against tsunami runup for structures along the oceanfront. Regular measurements of beach width and elevation can dictate the frequency and quantity of sand for replenishment projects. Develop and implement a tsunami educational program for residents and people who work in the susceptible areas. The program should provide the community with specific information about what a tsunami precursor looks like at the beach, and what appropriate actions to take in the event of a tsunami. Encourage the local school district to include in their earthquake -preparedness curriculum information specifically related to the natural hazards that Newport Beach's citizens could face, and what to do about them. Particularly important is the educational awareness of what an impending tsunami looks like while at the beach [sea level retreat, seiching, etc.], especially if in response to a local earthquake. Newport Beach should consider supplementing the State's funding for the University of Southern California Tsunami Research Group to complete its work in the Newport Beach offshore area, and to conduct more detailed studies in the Newport Bay area. • 1.8.2 Storm Surge 1.8.2.1 Hazard Assessment This hazard affects primarily ocean front property, and the low-lying areas of Newport Bay just inland from the jetties. Newport Bay is less affected by storm surge. Unlike tsunamis, which can occur anytime, storm surges are associated with bad weather. Given that during bad weather a lot less people are expected to be at the beach, storm surges are more likely to impact residents than tourists, and the potential number of casualties can be expected to be significantly less. The most common problem associated with storm surges is flooding of low-lying areas, including structures. This is often compounded by intense rainfall and strong winds. If a storm surge occurs during high tide, the flooded area can be significant. Coastal flooding in Newport Beach occurred in the past when major storms, many of these ENSO (El Nino Southern Oscillation) events, impacted the area. Storm surging associated with a tropical storm has been reported only once in the history of Newport Beach, in 1939. This suggests that the hazard of cyclone -induced storm surges has a low probability of occurrence. Nevertheless, the one incident in 1939 caused millions of dollars in damage to Newport Beach. 1.8.2.2 Hazard Mitigation Surge -induced flood protection involves maintaining a continuous barrier that is higher than the level of inundation expected. Typically this is accomplished with sand dunes, • seawalls, and bulkheads. The height of these protective structures is often a compromise between the need for protection, the need to accommodate buildings and other Earth Consultants International Coastal Hazards Page 1-30 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • infrastructure, and the need or desire to maintain views of the ocean (Nordstrom, 2000). In some areas, dunes are seen as temporary features that can be modified as needed using earth -moving equipment. In other areas, dunes are protected features that provide habitat for various native plant and animal species. Environmental reason dictates that vegetated dunes are preferable, however, in some areas raked and level beaches are considered to have a greater value due to their recreational potential. In Newport Beach, where both types of beaches occur, it seems appropriate to compromise. In the heavily used beaches where vegetation cannot be established due to intense foot and vehicular traffic, if a storm threatens, bulldozers can be used to build a temporary protective dune. This requires access to equipment in short notice. In the more natural beaches, where vegetated sand dunes are promoted, habitable structures should be located inland from the sand dunes using the setback distance as a protective measure. Beach nourishment programs help maintain the protective wide beaches and sand dunes. Newport Beach must develop a long-range plan to ensure that adequate (and increasingly larger) volumes of sand are available to the City for beach replenishment. In low-lying areas, storm drains should be maintained and cleaned out regularly, as necessary, so that flood waters can be effectively conveyed away from structures. In some areas near sea level, pumping may be required to manage flood waters. Relocating an oceanfront structure farther inland can be less expensive than rebuilding the structure if it is destroyed. However, in Newport Beach there is little opportunity for this option to be seriously considered. Under the California Coastal Act, a coastal development • permit is not required for the re -construction of any property destroyed by a natural disaster if the replacement structure footprint remains substantially the same (no more than 10% change from the original structure). Therefore, redevelopment after a natural disaster can include the same design or location that contributed to the first episode of property loss. Nevertheless, there are specific measures that can be taken to reduce the damage to structures caused by coastal conditions like storms. The Federal Emergency Management Agency (FEMA) publishes the Coastal Construction Manual that provides specific guidelines designed to safely site, design, construct and maintain coastal residential structures. The more recent version of this manual was issued in July 2000. Implementation of these guidelines above and beyond the requirements of the Building Code adopted by the City should be considered. Newport Beach could also develop a policy dealing with housing remodels in flood -prone zones that requires raising the floor elevations by at least 3 feet. The City should continue to enforce policies that prohibit the construction of seawalls, groins, or other hard devices to protect private property from tsunami, storm surge, or sea level rise. In addition, the City should consider policies that specify that if a structure is damaged as a result of coastal hazards, it should be subject to the floor -level raise requirements mentioned above, and that if a property is eroded away, the development right to that lot should be rescinded. 1.8.3 Seiches 1.8.3.1 Hazard Assessment Seiches are not considered a significant hazard in Newport Beach, primarily because there • is no record of Seiches impacting the area after both local and distant earthquakes. Wind - Earth Consultants International Coastal Hazards Page 1-31 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • generated seishes in Newport Bay have also not been reported. If a seiche developed in Newport Bay, the waves are expected to be low, impacting primarily moored boats. 1.8.3.2 Hazard Mitigation Mitigation designed specifically to reduce the hazard of seiches is not warranted. Mitigation measures implemented to reduce the hazards of tsunami, storm surge, and sea level rise, such as limiting construction along the waterfront of Newport Bay, are expected to mitigate the hazard of seiche. 1.8.4 Sea Level Rise 1.8.4.1 Hazard Assessment Sea level rise due to climate warming is expected to amplify coastal hazards such as storm surges, beach erosion, loss of wetlands, and degradation of fresh water quality due to seawater intrusion. A sea level rise of as little as 15 cm (6 inches) could negatively impact the Newport Beach area by flooding and eroding the narrow beaches south of the jetty area, which would result in increased erosion of the bluffs. The record of sea level rise in the last century is poorly constrained in this region, however. Gauge records up and down the Pacific Coast show substantial variations in relative sea level rise. Based on the historical records from the two gauges closest to Newport Beach, in Los Angeles and San Diego, a 15-cm rise in sea level in the Newport Beach area may take anywhere between 70 and 180 years, assuming that global warming does not accelerate in the next few decades. These estimates are too poorly constrained to engender policy changes and development of appropriate mitigation strategies. However, sea level rise would lead to the permanent inundation of low-lying areas, with potentially significant changes in land use, so it is not too soon to develop longer -term strategies that can be implemented to cope with these changes. 1.8.4.2 Hazard Mitigation To better constrain the trend in relative sea level change and predict sea level rise in the Newport Beach area, long-term sea -level gauges should be installed and operated on a continuous basis. These measuring devices should also measure tide variations, storm surges and other temporary changes in sea level that occur in response to weather conditions. All data recorded with these gauges should be archived in a format that can be easily retrieved for studies and monitoring of sea -level rise, and to evaluate the impact from storm surge and other coast flooding events. Better predictions of local sea level rise should be developed as these data are obtained. Beach nourishment requirements would increase to compensate for enhanced beach erosion resulting from sea level rise. In areas where beaches are narrow, artificial protection devices at the base of the bluffs, such as rock riprap aprons, may be required to reduce the effect of wave impact and storm surge on the exposed sea cliffs. This would temporarily protect the structures at the top of the bluffs, but at the expense of the beach. in the low-lying areas in Newport Bay, structures and infrastructure may have to be elevated. The potential adverse effects that mitigation measures may pose on adjoining properties and on the protected estuaries should be considered and evaluated over the next 20 to 30 years. The financial impact that sea level rise will pose on the community and . individual property owners should also be addressed. A GIS-based database of all properties in low-lying areas in the City, including the elevation of each structure, type of Earth Consultants International Coastal Hazards Page 1-32 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA construction, age, and value (based on monetary, historical, or other intrinsic criteria) should be considered. These data can then be used to perform a risk assessment study that can be used to identify those properties at greater risk, and to develop and prioritize mitigation alternatives best suited to the area. In many cases, the most cost-effective solution might be to simply allow the structure to be destroyed. 1.8.5 Coastal Erosion 1.8.5.1 Hazard Assessment Coastal erosion occurs and will continue to occur as a result of natural processes such as long -shore drift, storm surge and sea level rise. The Department of Boating and Waterways and the State Coastal Conservancy (2002) have jointly conducted a study that concluded that California beaches provide numerous benefits to the state and its residents, and these benefits are so valuable that it merits the State to invest a significant amount of money to restore and maintain its beaches. Specifically, the Department of Boating and Waterways estimates that California needs to spend $120 million in one-time beach restoration costs, and $27 million in annual beach maintenance costs. The preferred method of beach restoration is beach sand replenishment. As discussed previously, with increased erosion due to sea level rise and climatic changes associated with global warming, the need for sand replenishment will increase. Finding and obtaining adequate sources of beach sand material not impacted with foreign materials, such as glass and construction debris, may become a challenge. Increased environmental concerns associated with the mining and placement of these deposits along the coastline can also be anticipated. • Sea bluff erosion occurs as a result of processes that impact both the bottom and top of the cliffs. Pounding of the waves during high tide and storm surges causes considerable damage to the bottom of the bluffs. If the sediments exposed in this zone are soft and highly erodible, eventual collapse of the bluff can occur as it is undercut by wave action. Uncontrolled surface runoff, if allowed to flow over the top of the bluffs, can cause extensive erosion in the form of rills and gullies. During wet years, large canyons can develop quickly, often as a result of a single storm. Unchecked foot and vehicular traffic and rodent burrowing can also cause significant damage at the top of the bluffs. Increased irrigation associated with agricultural and residential watering can lubricate fine-grained layers in the sediments or bedrock forming the cliffs, leading to failure as a result of landsliding. • 1.8.5.2 Hazard Mitigation There is a strong interest in preserving the width and elevation of the beaches and protecting the beaches from erosion by natural coastal processes because beaches act as a buffer zone to low-lying areas immediately inland that maybe inundated by tsunami runup or storm surge. Continued beach replenishment will help maintain this buffer. Beaches are also a signature feature of Newport Beach, and generate substantial visitor income. The existing groin field and jetties should be maintained, as these structures are a part of the current stable system, and their removal is likely to trigger increased erosion in the area. Sand dunes, dikes and berms should also be maintained in good condition as these provide protection from coastal inundation. The City of Newport Beach currently monitors the width and elevation of its beaches twice annually. Earth Consultants International Coastal Hazards Page 1-33 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . "Hard" protective devices, such as revetments, bulkheads, seawalls, or breakwaters have historically been the most common approach to reducing shoreline erosion and protecting private or public structures. These structures reduce wave attack and backshore erosion and are often used to protect infrastructure serving the public. For example, the 6,000-foot seawall in Carlsbad protects a utility corridor and is the only north -south thoroughfare along that portion of the coastline, other than Interstate 5. The 54-year old O'Shaughnessy seawall at Ocean Beach in San Francisco, which protects Highway 1, is a similar example. In general, these structures provide greater public safety by protecting infrastructure and improving public access to the shore. If not designed properly, however, these structures can do more harm than good. Therefore, the potential negative impacts of these structures must be considered. Adverse impacts may include limiting public access to the shoreline, increasing erosion down coast, restricting sand input from protected bluffs, and disrupting the ocean view from the shore. In eroding beaches, a seawall will actually accelerate the destruction of the beach. Many structures of this kind are built on an emergency basis during heavy storm activity without proper engineering or appropriate materials, leading to their eventual failure and increased damage to the coastline. Raising existing bulkheads has been proposed to protect structures from sea level rise, however, this should also not be done without consideration of local conditions. For example, along the oceanfront, increasing bulkhead heights can cause deepening of the ocean bottom. This results in increased wave energy impacting the bulkhead, which can lead to the potential failure of the structure or nearby structures. Raised bulkheads along the oceanfront are not recommended. On the other hand, bulkheads in the lower energy . environment of Newport Bay would protect structures from rising sea levels. While protective structures may be built to protect existing development or coastal - dependent facilities, the California Coastal Act requires that new, non -coastal dependent developments not be built if it is known that the development will require a protective structure in the future. This is an appropriate policy, as avoidance would reduce costs associated with future disaster relief, construction of protective devices, and government disaster assistance. • The City of Newport Beach has policies in place limiting development adjacent to bluffs. Enforcement of these policies should be continued. Subsurface drains installed below the effective root line of most landscaping plants should be considered in areas near the bluffs to collect the extra rainwater and irrigation water not utilized by plants. This will prevent a rise in the local groundwater level that can lead to increased erosion or failure of the bluffs. Landscaping areas near the bluffs with drought -resistant plants that require little or no watering should also be encouraged. Earth Consultants International Coastal Hazards Page 1-34 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . Informational Websites and References littp://www.prh.iioaa,goy42i:/2twc/bulletiiis.litm Pacific Tsunami Warning Center National Weather Service http://www.usc.edu/depYtsunami USC Tsunami Research Group httl2://www.oes.ca.gQv/ California Office of Emergency Services littp://www.12niel.noaa.gov/tsunami-hazard/ The National Tsunami Hazard Mitigation Program littp://Iiurricanes.noaa.gov The National Oceanic and Atmospheric Administration web page on hurricanes and other coastal processes littl2://www.usatoday.com/weather/whiicalif.litm Alford, Stephen, 2002 personal communication, City of Newport Beach Senior Planner, via written • correspondence to Earth Consultants International, dated September 10, 2002. Badum, Stephen G., 2002 personal communication, City of Newport Beach Public Works Director, via written correspondence to Mr. Patrick Alford, City of Newport Beach Senior Planner, dated September 13, 2002. Bates, R.L., and Jackson, J.A., 1987, editors, Glossary of Geology: American Geological Institute, Alexandria, Virginia, 788p. Borrero, J., Dolan J., Synolakis, C.E., 2001, Tsunami sources within the Eastern Santa Barbara Channel: Geophysical Research Letters, Vol. 28, pp. 643-647. Brandsma, M., Divoky, d., and Hwang, L.S., 1978, Circumpacific variation of computed tsunami features in Tsunami Symposium: Ottawa, Canada, Marine Sciences Directorate, Department of Fisheries and Environment Manuscript Report Series 48, pp. 132-151. Byerly, P. 1930, The California earthquakes of November 4, 1927: Bulletin of the Seismological Society of America, Vol. 20, pp. 53-66. California Division of Mines and Geology (CDMG), 1976, Environmental Geology of Orange County, California: Division of Mines and Geology Open -file Report 79-8 LA, 474p. Clarke, S.H., Jr., Greene, H.G., and Kennedy, M.P., 1985, Earthquake -related phenomena offshore • in Ziony, I., (editor), Evaluating Earthquake Hazards in the Los Angeles Region: United States Geological Survey Professional Paper 1360, pp. 347-374. Earth Consultants International Coastal Hazards Page 1-35 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Department of Boating and Waterways and State Coastal Conservancy, 2002, California Beach Restoration Study: Sacramento, California. Copies of this report may be obtained on the internet at: http://www.dbw.ca.gov/beach report. htm Eisner, R.K., Borrero, J.C. and Synolakis, C.E., 2001, Inundation maps for the State of California. Ewing, L. and Wallendorf, L., (editors), 2002, Solutions to Coastal Disasters '02: Conference Proceedings of the meeting held in San Diego, California on February 24-27, 2002: American Society of Civil Engineers, Reston, Virginia, 1,019p. Field, M.E., and Edwards, B.D., 1980, Slopes of the southern California continental borderland: A regime of mass transport in Field, M.E., Bouma, A.H., Colburn, I.P., Douglas, R.G., and Ingle, J.C., (editors), Proceedings of the Quaternary depositional environments of the Pacific Coast: Pacific Coast Paleogeography Symposium No. 4: Los Angeles California Society of Economic Paleontologists and Mineralogists, Pacific Section, pp. 169-184. Garcia, A.W., and Houston, J.R., 1975, Type 16 flood insurance study — Tsunami predictions for Monterey and San Francisco Bays and Puget Sound: U.S. Army Corps of Engineers Waterways Experiment Station Technical Report H-75-17, 21 p. Garrison, T., 2002, Oceanography — An Invitation to Marine Science: Wadsworth Publishing House, Belmont, California, 41h Edition. • Grauzinis, V. J., Joy, J.W., and R. R. Putz, The Reported Tsunami of December 1812, unpublished manuscript. Heck, N.H., 1947, List of Seismic Sea Waves: Bulletin of the Seismological Society of America, Vol. 37, No. 4. Houston, J.R., 1980, Type 19 flood insurance study: Tsunami predictions for southern California: U.S. Army Corps of Engineers Waterways Experimental Station Technical Report HL-80-18, 172p. Houston, J.R., and Butler, H.L., 1979, A numerical model for tsunami inundation: US. Army Corps of Engineers Waterways Experimental Station Technical Report HL-79-2, 54p. Houston, J.R, and Garcia, A.W., 1974, Type 16 flood insurance study: Tsunami predictions for Pacific coastal communities: U.S. Army Corps of Engineers Waterways Experiment Station Research Report H-74-3, 10p. Houston, J.R., and Garcia, A.W., 1978, Type 16 flood insurance study: Tsunami predictions for the west coast of the United States: U.S. Army Corps of Engineers Waterways Experiment Station Research Report H-78-26, 38p. Houston, J.R., Whalin, R.W., Garcia, A.W., and Butler, H.L., 1975, Effect of source orientation and • location in the Aleutian Trench on tsunami amplitude along the Pacific coast of the Earth Consultants International Coastal Hazards Page 1-36 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • continental United States: U.S. Army Corps of Engineers Waterways Experiment Station Research Report H-75-4, 22p. lida, K., 1963, Magnitude, energy, and generation mechanisms of tsunamis and a catalog of earthquakes associated with tsunamis; in Proceedings of the 10"' Pacific Science Congress Symposium: International Union of Geodesy and Geophysics Monograph NO. 24, pp. 7- 18. lida K., Cox, D. C, and G. Pararas-Carayannis, 1967, Preliminary Catalog of Tsunamis Occurring in the Pacific Ocean: University of Hawaii, Honolulu. Imamura, A., 1949, List of Tsunamis in Japan: Journal of the Seismological Society of Japan, Vol. 2, pp. 22-28 (in Japanese, as referenced in McCulloch, 1985). Joy, J.W., 1968, Tsunamis and their Occurrence along the San Diego County Coast: Westinghouse Ocean Research Laboratory Report, No. 68-567-OCEAN-RL, San Diego, California. Knuuti, Kevin, 2002, Planning for Sea Level Rise: U.S. Army Corps of Engineers Policy; in Ewing, L. and Wallendorf, L., (editors), Solutions to Coastal Disasters '02: Conference Proceedings of the meeting held in San Diego, California on February 24-27, 2002: American Society of Civil Engineers, Reston, Virginia, pp. 549-560. Kuhn, G.G. and Shepard, F.P., 1984, Sea Cliffs, Beaches and Coastal Valleys of San Diego County: • Some Amazing Stories and Some Horrifying Implications: University of California Press, Berkeley and Los Angeles, California, 193p. Kuhn, G.G. and Shepard, F.P., 1985, Beach Processes and Sea Cliff Erosion in San Diego County, California: Handbook of Coastal Processes and Erosion, edited by Komar, P.D, CRC Press. Lajoie, K.R., Ponti, D.J., Powell II, S.A., Mathieson, S.A, and Sarna-Wojcicki, 1991, Emergent Marine Strandlines and Associated Sediments, Coastal California; A Record of Quaternary Sea -Level Fluctuations, Vertical Tectonic Movements, Climatic Changes, and Coastal Processes; in Morrison, R.B., (editor), Quaternary Nonglacial Geology: Conterminous U.S.: The Geological Society of America, The Decade of North American Geology, Volume K-2, pp. 191-214. Lander, J.F., and P.A. Lockridge, 1989, United States Tsunamis 1690-1988: U.S. Department of Commerce, Publication 41-2. Long, E.E., 1988, Acting Chief of Tide and Current Prediction Section, NOAA, National Ocean Survey, personal communication with James E. Lander, CIRES, September 19, 1988, as reported in Lander and Lockridge, 1989. Marine Advisors, Inc., (compilers), 1965, Examination of Tsunami Potential at the San Onofre Nuclear Generating Station, Report A-163, Los Angeles, California. Earth Consultants International Coastal Hazards Page 1-37 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • McCarthy, R.J., Bernard, E.N., and Legg, M.R., 1993, Coastal Zone'93, Processes of the American Shore and Beach Preserve Association: American Society of Civil Engineers meeting in New Orleans, Louisiana. McCulloch, D. S., 1985, Evaluating Tsunami Potential in Ziony, I., (editor), Evaluating Earthquake Hazards in the Los Angeles Region: United States Geological Survey Professional Paper 1360, pp. 375-413. McGarr, A., Vorhis, R. C., 1968, Seismic seiches from the March 1964 Alaska earthquake: U.S. Geological Survey Professional Paper 544-E, 43p. Meier, M.F. 1984, Contribution of Small Glaciers to Global Sea Level: Science, Vol. 226, pp. 1418-1421. Mercer, J.H. 1970, Antarctic Ice and Interglacial High Sea Levels: Science, Vol. 168, pp. 1605- 1606. Montandon, F., 1928, Tremblements de Terre: Moterdaux pour I'Etude des Calamites, Geneva, Switzerland, No. 16, 345p. National Research Council, 1987, Responding to Changes in Sea Level: Engineering Implications: National Academy Press, Washington, D.C. • Newport Beach, 1975. Public Safety Element, Newport Beach General Plan. Nordstrom, Karl F., 2000, Beaches and Dunes of Developed Coasts: Cambridge University Press, Cambridge, United Kingdom, 338. • Oldale, R., 1985, Late Quaternary Sea Level History of New England: A Review of Published Sea Level Data: Northeastern Geology, Vol. 7, pp. 192- 200. Peltier, W.R., and A.M. Tushingham, 1989, Global Sea Level Rise and the Greenhouse Effect: Might They Be Connected?: Science, Vol. 244, pp. 806-810. Salsman, G. S., 1959, The Tsunami of March 9, 1957 as Recorded at Tide Stations: United States Coast and Geodetic Survey, Technical Bulletin No. 6. Stermitz, Frank, 1964, Effects of the Hebgen Lake earthquake on surface water: U.S. Geological Survey Professional Paper 435, pp. 139-150. Soloviev, S.L., and Go, C.N., 1975, A catalogue of Tsunamis of the Eastern Shore of the Pacific Ocean: Academy of Sciences of the USSR, "Nauka" Publishing House, Moscow, 204p. Spaeth M.G. and S.C. Berkman, 1972, Tsunami of March 28, 1968 as Recorded at Tide Stations at the Seismic Sea Wave Warning System, in The Great Alaska Earthquake of 1964: Oceanography and Coastal Engineering, National Academy of Sciences, pp. 38-110. Earth Consultants International Coastal Hazards Page 1-38 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Synolakis C.E., 1987, The runup of solitary waves: Journal of Fluid Mechanics, Vol. 185, pp. 523- 545. Synolakis, C.E., Liu, P.L., Yeh, H., and Carrier, G., 1997, Tsunamigenic seafloor deformations: Science, Vol. 278, pp. 598-600. Synolakis, C.E., Borrero, J., and Eisner, R., 2002, Developing Inundation Maps for Southern California; in Ewing, L. and Wallendorf, L., (editors), Solutions to Coastal Disasters '02: Conference Proceedings of the meeting held in San Diego, California on February 24-27, 2002: American Society of Civil Engineers, Reston, Virginia, pp. 848-862. Synolakis, Costas Emmanuel, 2002, Professor of Civil Engineering, University of Southern California, Los Angeles, California, and Director of the University of Southern California Tsunami Research Group, personal communication via telephone and e-mail regarding tsunami inundation maps for Orange County and Newport Beach. Talley, C.H., Jr. and W. K. Cloud, (editors), 1962, United States Earthquakes, 1960: United States Coast and Geodetic Survey. Titov, V.V. and Synolakis, C.E., 1998, Numerical modeling of tidal wave runup: Journal of Waterways, Port, Coastal and Ocean Engineering, ASCE, Vol. 124, No. 4, pp. 157-171. Titus, J.G., 1990, Greenhouse Effect, Sea Level Rise, and Barrier Islands: Case Study of Long • Beach Island, New Jersey: Coastal Management, Vol. 18, pp. 65-90. Titus, J.G., Park, R.A., Leatherman, S.P., Weggel, J.R., Greene, M.S., Mausel, P.W., Brown, S., Gaunt, C., Trehan, M. and Yohe, G., 1991, Greenhouse Effect and Sea Level Rise: The Cost of Holding Back the Sea: Coastal Management, Vol. 19, pp. 171-210. Toppozada, T.R., Real, C.R., and D.L. Parke, 1981, Preparation of Isoseismal Maps and Summaries of Reported Effects for Pre-1900 California Earthquakes: California Division of Mines and Geology Open File Report 81-11 SAC. Trask, J.B., 1856, Untitled paper on earthquakes in California from 1812 to 1855: Proceedings of the California Academy of Natural Science, San Francisco, Vol. 1, No. 2. U.S. Army Corps of Engineers, Los Angeles District, February 1986, Coast of California Storm and Tidal Waves Study: Southern California Coastal Processes Data Summary, Ref. No. CCSTWS 86-1, 572p. U.S. Army Corps of Engineers, Los Angeles District, November 1993, Condition Survey for Entrance Jetties, Newport Bay Harbor, Orange County, California. U.S. Army Corps of Engineers, South Pacific Division, Los Angeles District, May 1995, Surfside- SunseVWest Newport Beach Nourishment Project, Orange County, California. • U.S. Geological Survey, 2002, Fact Sheet 175-99. Earth Consultants International Coastal Hazards Page 1-39 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Walker, J.R., Nathan, R.A., and Seymour, R.J., 1984, Coastal Design Criteria in Southern California: Abstracts, 19'h International Conference of Coastal Engineering, Sept. 3-7, 1984, in Houston, Texas, published by the American Society of Civil Engineers, pp. 186- 187. • Wilcoxen, P.J. 1986, Coastal Erosion and Sea Level Rise: Implications for Ocean Beach and San Francisco's Westside Transport Project: Coastal Zone Management, Vol. 14, No. 3, pp. 173-191. Wood, H.O., 1916, California Earthquakes —A Synthetic Study of Recorded Shocks: Bulletin of the Seismological Society of America, Vol. 6, No. 2. Zervas, Chris, to be published, Sea Level Variations of the United States, 1854-1999: Technical Report, National Oceanic and Atmospheric Administration (as referenced in Knuuti, 2002). Earth Consultants International Coastal Hazards Page 1-40 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA ACHAPTER 2: SEISMIC HAZARDS 2.1 Introduction While Newport Beach is at risk from many natural and man-made hazards, an earthquake is the event with the greatest potential for far-reaching loss of life or property, and economic damage. This is true for most of southern California, since damaging earthquakes are frequent, affect widespread areas, trigger many secondary effects, and can overwhelm the ability of local jurisdictions to respond. Earthquake -triggered geologic effects include ground shaking, surface fault rupture, landslides, liquefaction, subsidence and seiches, all of which are discussed below. Earthquakes can also lead to urban fires, dam failures, and toxic chemical releases. These man - related hazards are also discussed in this document. In California, recent earthquakes in or near urban environments have caused relatively few casualties. This is due more to luck than design. For example, when a portion of the Nimitz Freeway in Oakland collapsed at rush hour during the 1989, MW 7.1 Loma Prieta earthquake, the traffic was uncommonly light because so many were watching the World Series. The 1994, MW 6.7 Northridge earthquake occurred before dawn, when most people were home safely in bed. Despite such good luck, California's urban earthquakes have resulted in significant losses. The moderate -sized Northridge earthquake caused 54 deaths and nearly $30 billion in damage. Newport Beach is at risk from earthquakes that could release more than 10 times the seismic energy of the Northridge earthquake. Although it is not possible to prevent earthquakes, their destructive effects can be minimized. . Comprehensive hazard mitigation programs that include the identification and mapping of hazards, prudent planning, public education, emergency exercises, enforcement of building codes, and expedient retrofitting and rehabilitation of weak structures can significantly reduce the scope of an earthquake's effects and avoid disaster. Local government, emergency relief organizations, and residents must take action to develop and implement policies and programs to reduce the effects of earthquakes. 2.2 Earthquake and Mitigation Basics 2.2.1 Definitions The outer 10 to 70 kilometers of the Earth consist of enormous blocks of moving rock, called tectonic plates. There are about a dozen major plates, which slowly collide, separate, and grind past each other. In the uppermost brittle portion of the plates, friction locks the plate edges together, while plastic movement continues at depth. Consequently, the near -surface rocks bend and deform near plate boundaries, storing strain energy. Eventually, the frictional forces are overcome and the locked portions of the plates move. The stored strain energy is then released in seismic waves. By definition, the break or fracture between moving blocks of rock is called a fault, and such differential movement produces a fault rupture. The point where the fault rupture originates is called the focus (or hypocenter). The released energy radiates out in all directions from the rupture surface causing the Earth to vibrate and shake as the waves travel through. This shaking is what we feel in an earthquake. Earth Consultants International Seismic Hazards Page 2-1 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Although faults exist everywhere, most earthquakes occur on or near plate boundaries. Thus, southern California has many earthquakes, because it straddles the boundary between the North American and Pacific plates, and fault rupture accommodates their motion. Newport Beach is riding on the Pacific Plate, which is moving northwesterly (relative to the North American Plate), at about 50 mm/yr. This is about the rate at which fingernails grow, and seems unimpressive. However, it is enough to accumulate enormous amounts of strain energy over dozens to thousands of years. Despite being locked in place most of the time, in another 15 million years (a short time in the context of the Earth's history), due to plate movements, Newport Beach will be hundreds of kilometers north of San Francisco. Although the San Andreas fault marks the actual separation between the Pacific and North American plates, only about 70 percent of the plate motion actually occurs on this fault. The rest is distributed along other faults of the San Andreas system, including the San Jacinto, Whittier -Elsinore, Newport -Inglewood, Palos Verdes, and several offshore faults. To the east of the San Andreas fault, slip is distributed among faults of the Eastern Mojave Shear Zone, including those responsible for the 1992, MW 7.3 Landers and 1999 MW 7.1 Hector Mine earthquakes. (MW stands for moment magnitude, a measure of earthquake energy release, discussed below.) Thus, the zone of plate -boundary earthquakes and ground deformation covers an area that stretches from Nevada to the Pacific Ocean (Figure 2-1). Because the Pacific and North American plates are sliding past each other, with relative • motions to the northwest and southeast, respectively, all of the faults mentioned above trend northwest -southeast, and are strike -slip faults. On average, strike -slip faults are nearly vertical breaks in the rock, and when a strike -slip fault ruptures, the rocks on either side of the fault slide horizontally past each other. u However, there is a kink in the San Andreas fault commonly referred to as the "Big Bend". The northwest corner of the Big Bend is located about 75 miles north of Newport Beach (Figure 2-1). Near the Big fiend, the two plates do not slide past each other. Instead, they collide, causing localized compression, which then results in folding and thrust faulting. Thrust faults meet the surface of the Earth at a low angle, dipping 25 to 35 degrees from horizontal. Thrusts are a type of dip -slip fault where rocks on opposite sides of the fault move up or down relative to each other. When a thrust fault ruptures, the top block of rock moves up and over the rock on the opposite side of the fault. In southern California, ruptures along thrust faults have built the Transverse Ranges geologic province, a region with an east -west trend to its landforms and underlying geologic structures. This orientation is anomalous, virtually unique in the western United States, and is a direct consequence of the plates colliding at the Big Bend. Many of southern California's most recent damaging earthquakes have occurred on thrust faults that are uplifting the Transverse Ranges, including the 1971 MW 6.7 San Fernando, the 1987 MW 5.9 Whittier Narrows, the 1991 MW 5.8 Sierra Madre, and the 1994 MW 6.7 Northridge earthquakes. Earth Consultants International Seismic Hazards Page 2-2 2003 • 36 34 32 wlipa \ \ \ San Andreas Faun \\ BIG Garo aurF It \ \ \ EASTERN %NEVADA BEND / MOJAVE CALIFORNIA\\ SHEAR ZONE \ akt rra \ -- --- Madre- .- Cucamonga �e RaP9 Fault Palos Verdes Fault \--r� PACIFIC p OCEAN �8 0 100 kilometers �JJ SourceModified from Fuis and Mooney, 1990 uvNQQ\d Jacrn \ A )Ot'� Fault a h Rose Canyo Fault Sea Colorado River ilil. o \ CALIFORNa v mo. MFjtICO �� li 0 Cerro Preto 't` \ Fault \ Gulf of Californi I'� I_1 »:i l Aid ► lc� ��P.l Fault _Onshore Spreading Center Earth `— Consultants Intemational • I Project Number: 2112 Date: January, 2003 New Crust (late Cenozoic) I Figure Regional Fault Map 2.1 U • 0 185719 ,, •�\` \ / 1940 — �— - 1925" 1994� yr1 1979 1989 1933 Pacific Ocean �0 0 Source: Jennings, 1994; SCEC earthquake catalog; NEIC earthquake catalog Map Explanation Magnitude 7+ Magnitude 5 - 6 Magnitude 6 - 7 Quaternary faults 1923 '1910 of — Earth �htemaiionnal Regional Seismicity Map Figure Project Number. 2112 2-2 Date: January, 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Thrust faults can be particularly hazardous because many are "blind" thrust faults, that is, they do not extend to the surface of the Earth. These faults are extremely difficult to detect before they rupture. Some of the most recent earthquakes, like the 1987 Whittier Narrows earthquake and the 1994 Northridge earthquake, occurred on previously unknown blind thrust faults. The city of Newport Beach is situated in the northern part of the Peninsular Ranges Province, an area that is exposed to risk from multiple earthquake fault zones. The highest risks originate from the Newport -Inglewood (strike -slip, right -lateral) fault zone, the Whittier (strike -slip, right -lateral) fault zone, the San Joaquin Hills (blind thrust) fault, and the Elysian Park (blind thrust) fault zone. Each one of these faults will be discussed in more detail in Section 2-5. 2.2.2 Evaluating Earthquake Hazard Potential When comparing the sizes of earthquakes, the most meaningful feature is the amount of energy released. Thus scientists most often consider seismic moment, a measure of the energy released when a fault ruptures. We are more familiar, however, with scales of magnitude, which measure amplitude of ground motion. Magnitude scales are logarithmic. Each one -point increase in magnitude represents a ten -fold increase in amplitude of the waves as measured at a specific location, and a 32-fold increase in energy. That is, a magnitude 7 earthquake produces 100 times (10 x 10) the ground motion amplitude of a magnitude 5 earthquake. Similarly, a magnitude 7 earthquake releases approximately 1,000 times more energy (32 x 32) than a magnitude 5 earthquake. • Recently, scientists have developed the moment magnitude (MK,) scale to relate energy release to magnitude. An early measure of earthquake size still used today is the seismic intensity scale, which is a qualitative assessment of an earthquake's effects at a given location. Although it has limited scientific application, intensity is still widely used because it is intuitively clear and quick to determine. The most commonly used measure of seismic intensity is called the Modified Mercalli Intensity (MMI) scale, which has 12 damage levels (Table 2-1). A given earthquake will have one moment and, in principle, one magnitude, although there are several methods of calculating magnitude, which give slightly different results. However, one earthquake will produce many levels of intensity because intensity effects vary with the location and the perceptions of the observer. Few faults are simple, planar breaks in the Earth. They more often consist of smaller strands, with a similar orientation and sense of movement. A strand is mappable as a single, fairly continuous feature at a scale of about 1:24,000. Sometimes geologists group strands into segments, which are believed capable of rupturing together during a single earthquake. The more extensive the fault, the bigger the earthquake it can produce. Therefore, multi -strand fault ruptures produce larger earthquakes. Earth Consultants International Seismic Hazards Page 2-5 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Table 2-1: Abridged Modified Mercalli Intensity Scale Average Peak Average Peak Intensity Value and Description Velocity Acceleration (cm/sec) (g = gravity ) 1. Not felt except by a very few under especially favorable circumstances (I <0.1 <0.0017 Rossi-Forel scale). Damagepotential: None. IL Felt only by a few persons at rest, especially on upper floors of high-rise buildings. Delicately suspended objects may swing. (I to II Rossi-Forel scale). Damagepotential: None. 0.1-1.1 0.0017-0.014 III. Felt quite noticeably indoors, especially on upper floors of buildings, but many people do not recognize it as an earthquake. Standing automobiles may rock slightly. Vibration like passing of truck. Duration estimated. (III Rossi-Forel scale). Damagepotential: None. IV. During the day felt indoors by many, outdoors by few. At night some awakened. Dishes, windows, doors disturbed; walls make creaking sound. Sensation like a heavy truck striking building. Standing automobiles rocked 1.1 —3.4 0.014 - 0.039 noticeably. (IV to V Rossi -Fore[ scale). Damage potential: None. Perceived shaking: Light. V. Felt by nearly everyone; many awakened. Some dishes, windows, and so on broken; cracked plaster in a few places; unstable objects overturned. Disturbances of trees, poles, and other tall objects sometimes noticed. 3.4— 8.1 0.039-0.092 Pendulum clocks may stop. IV to VI Rossi-Forel scale). Damage potential: Very light. Perceived shaking: Moderate. VI. Felt by all; many frightened and run outdoors. Some heavy furniture moved, few instances of fallen plaster and damaged chimneys. Damage slight. (VI to 8.1 -16 0.092 -0.18 VII Rossi -Fore) scale). Damage potential: Light. Perceived shaking: Strong. VIL Everybody runs outdoors. Damage negligible in buildings of good design and construction; slight to moderate in well-built ordinary structures; considerable in poorly built or badly designed structures; some chimneys 16 - 31 0.18 - 0.34 broken. Noticed by persons driving cars. (VIII Rossi -Fore] scale). Damage potential: Moderate. Perceived shaking: Very strong. VIII. Damage slight in specially designed structures, considerable in ordinary substantial buildings with partial collapse; great in poorly built structures. Panel walls thrown out of frame structures. Fall of chimneys, factory stacks, columns, monuments, and walls. Heavy furniture overturned. Sand and 31 - 60 0.34 - 0.65 mud ejected in small amounts. Changes in well water. Persons driving cars disturbed. (VIII+to IX Rossi-Forel scale). Damage potential: Moderate to heavy, Perceived shaking: Severe. IX. Damage considerable in specially designed structures; well -designed frame structures thrown out of plumb; great in substantial buildings with partial collapse. Buildings shifted off foundations. Ground cracked conspicuously. 60 -116 0.65 —1.24 Underground pipes broken. flX+ Rossi-Forel scale). Damage potential: Heavy, Perceived shaking: Violent. X. Some well-built wooden structures destroyed; most masonry and frame structures destroyed; ground badly cracked. Rails bent. Landslides considerable from river banks and steep slopes. Shifted sand and mud. > 116 > 1.24 Water splashed, slopped over banks. (X Rossi -Fore] scale). Damage potential: Very heavy. Perceived shaking: Extreme. XI. Few, if any, (masonry) structures remain standing. Bridges destroyed. Broad fissures in ground. Underground pipelines completely out of service. Earth slumps and land slips in soft ground. Rails bent greatly. XII. Damage total. Waves seen on ground surface. Lines of sight and level distorted. Objects thrown into air. Modified from Bolt (1999); Wald et al. (1991 Earth Consultants International 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The bigger and closer the earthquake, the greater the damage it may generate. Thus fault dimensions and proximity are key parameters in any hazard assessment. In addition, it is important to know a fault's style of movement (i.e., is it dip -slip or strike -slip, discussed above), the age of its most recent activity, its total displacement, and its slip rate (all discussed below). These values allow an estimation of how often a fault produces damaging earthquakes, and how big an earthquake should be expected the next time the fault ruptures. Total displacement is the length, measured in kilometers (km), of the total movement that has occurred along the fault over as long a time as the geologic record reveals. It is usually estimated by measuring distances between geologic features that have been split apart and separated (offset) by the cumulative movement of the fault over many earthquakes. Slip rate is a speed, expressed in millimeters per year (mm/yr). Slip rate is estimated by measuring an amount of offset accrued during a known amount of time, obtained by dating the ages of geologic features. Slip rate data also are used to estimate a fault's earthquake recurrence interval. Sometimes referred to as "repeat time" or "return interval", the recurrence interval represents, the average amount of time that elapses between major earthquakes on a fault. The most specific way to derive the recurrence interval for a given fault is to excavate a trench across the fault to obtain paleoseismic evidence of earthquakes that have occurred during prehistoric time. Paleoseismic studies show that faults with higher slip rates often have shorter recurrence intervals between major earthquakes. This makes sense because a high slip rate indicates rocks that, at depth, are moving relatively quickly. Thus the locked, surficial rocks are storing more strain energy, so the forces of friction will be exceeded more often, releasing the strain energy in more frequent, large earthquakes. Faults have formed over millions of years, usually in response to regional stresses. Shifts in these stress regimes do occur over millennia. As a result, some faults change in character. For example, a thrust fault in a compressional environment may become a strike -slip fault in a transpressive (oblique compressional) environment. Other faults may be abandoned altogether. Consequently, the State of California, under the guidelines of the Alquist-Priolo Earthquake Fault Zoning Act of 1972 (Hart and Bryant, 1999), classifies faults according to the following criteria: Active: faults showing proven displacement of the ground surface within about the last 11,000 years (within the Holocene Epoch), that are thought capable of producing earthquakes; Potentially Active: faults showing evidence of movement within the last 1.6 million years, but that have not been shown conclusively whether or not they have moved in the last 11,000 years; and Not active: faults that have conclusively NOT moved in the last 11,000 years. • The Alquist-Priolo classification is used primarily for residential subdivisions. Different definitions of activity are used by other agencies or organizations depending on the type of Earth Consultants International Seismic Hazards Page 2-7 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • facility being planned or developed. For example, longer periods of inactivity may be required for dams or nuclear power plants. An important subset of active faults are those with historical earthquakes. In California, that means faults that have ruptured since 1769, when the Spanish first settled in the area. The underlying assumption in this classification system is that if a fault has not ruptured in the last 11,000 years, it is not likely to be the source of a damaging earthquake in the future. In reality, however, most potentially active faults have been insufficiently studied to determine their hazard level. Also, although simple in theory, the evidence necessary to determine whether a fault has or has not moved during the last 11,000 years can be difficult to obtain. For example, some faults leave no discernable evidence of their earthquakes, while other faults stop rupturing for millennia, and then are "reactivated" as the tectonic environment changes. 2.2.3 Causes of Earthquake Damage Causes of earthquake damage can be categorized into three general areas: strong shaking, various types of ground failure that are a result of shaking, and ground displacement along the rupturing fault. The State definition of an active fault is designed to gauge the surface rupture potential of a fault, and is used to prevent development from being sited directly on an active fault. This helps to reduce damage from the third category. Below, the three categories are discussed in order of their likelihood to occur extensively: 1) Strong ground shaking causes the vast majority of earthquake damage. Horizontal • ground acceleration is frequently responsible for widespread damage to structures, so it is commonly estimated as a percentage of g, the acceleration of gravity. Full characterization of shaking potential, though, requires estimates of peak (maximum) ground displacement and velocity, the duration of strong shaking, and the periods (lengths) of waves that will control each of these factors at a given location. We look to the recorded effects of damaging earthquakes worldwide to understand what might happen in similar environments here in the future. In general, the degree of shaking can depend upon: ♦ Source effects. These include earthquake size, location, and distance, as discussed above. In addition, the exact way that rocks move along the fault can influence shaking. For example, the 1995, MW 6.9 Kobe, Japan earthquake was not much bigger than the 1994, MW 6.7 Northridge, California earthquake, but the city of Kobe suffered much worse damage. During the Kobe earthquake, the fault's orientation and movement directed seismic waves into the city. During the Northridge earthquake, the fault's motion directed waves away from populous areas. ♦ Path effects. Seismic waves change direction as they travel through the Earth's contrasting layers, just as light bounces (reflects) and bends (refracts) as it moves from air to water. Sometimes seismic energy gets focused into one location and causes damage in unexpected areas. Focusing of 1989's MW 7.1 Loma Prieta earthquake waves caused damage in San Francisco's Marina district, some 62 miles • (100 km) distant from the rupturing fault. Earth Consultants International Seismic Hazards Page 2-8 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • ♦ Site effects. Seismic waves slow down in the loose sediments and weathered rock at the Earth's surface. As they slow, their energy converts from speed to amplitude, which heightens shaking. This is like the behavior of ocean waves — as the waves slow down near shore, their crests grow higher. The Marina District of San Francisco also serves as an example of site effects. Earthquake motions were greatly amplified in the deep, sediment -filled basin underlying the District compared to the surrounding bedrock areas. Seismic waves can get trapped at the surface and reverberate (resonate). Whether resonance will occur depends on the period (the length) of the incoming waves. Waves, soils and buildings all have resonant periods. When these coincide, tremendous damage can occur. We keep talking about periods. What do we mean? Waves repeat their motions with varying frequencies. Slow -to -repeat waves are called long -period waves. Quick -to - repeat waves are called short -period waves. Long -period seismic waves, which are created by large earthquakes, are most likely to reverberate and cause damage in long - period structures, like bridges and high-rises. ("Long -period structures" are those that respond to long -period waves.) Shorter -period seismic waves, which tend to die out quickly, will most often cause damage fairly near the fault, and they will cause most damage to shorter -period structures such as one- to three-story buildings. Very short - period waves are most likely to cause near -fault, interior damage, such as to equipment. 2) Liquefaction and slope failure are very destructive secondary effects of strong seismic shaking. ♦ Liquefaction typically occurs within the upper 50 feet of the surface, when saturated, loose, fine- to medium -grained soils (sand and silt) are present. Earthquake shaking suddenly increases pressure in the water that fills the pores between soil grains, causing the soil to lose strength and behave as a liquid. This process can be observed at the beach by standing on the wet sand near the surf zone. Standing still, the sand will support your weight. However, when you tap the sand with your feet, water comes to the surface, the sand liquefies, and your feet sink. When soils liquefy, the structures built on them can sink, tilt, and suffer significant structural damage. Liquefaction -related effects include loss of bearing strength, ground oscillations, lateral spreading and flow failures or slumping. The excess water pressure is relieved by the ejection of material upward through fissures and cracks. A water -soil slurry bubbles onto the ground surface, resulting in features called "sand boils", "sand blows" or "sand volcanoes". Site -specific geotechnical studies are the only practical, reliable way to determine the liquefaction potential of a site. ♦ Landslides and Rockfall (Mass Wasting). Gravity inexorably pulls hillsides down and earthquake shaking enhances this on -going process. Slope stability depends on many factors and their interrelationships. Rock type and pore water pressure are arguably the most important factors, as well as slope steepness due to natural or human -made undercutting. Where slopes have failed before, they may fail again. Earth Consultants International Seismic Hazards Page 2-9 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Thus, it is essential to map existing landslides and soil slumps. Furthermore, because there are predictable relationships between local geology and the likelihood that mass wasting will occur, field investigations can be used to identify failure -prone slopes before an earthquake occurs. Combined with GIS-based analyses of slope gradient, land use, and bedrock or soil materials, this information can be used to identify high -risk areas where mitigation measures would be most effective. 3) Primary ground rupture due to fault movement typically results in a relatively small percentage of the total damage in an earthquake, yet being too close to a rupturing fault can result in extensive damage. It is difficult to safely reduce the effects of this hazard through building and foundation design. Therefore, the primary mitigation measure is to avoid active faults by setting structures back from the fault zone. Application of this measure is subject to requirements of the Alquist-Priolo Earthquake Fault Zoning Act and guidelines prepared by the California Geological Survey — previously known as the California Division of Mines and Geology (CDMG Note 49). The final approval of a fault setback lies with the local reviewing agency. Earthquake damage also depends on the characteristics of human -made structures. The interaction of ground motion with the built environment is complex. Governing factors include a structure's height, construction, and stiffness, which determine the structure's resonant period; the underlying soil's strength and resonant period; and the periods of the incoming seismic waves. Other factors include architectural design, condition, and age of . the structure. 2.2.4 Choosing Earthquakes for Planning and Design it is often useful to create a deterministic or design earthquake scenario to study the effects of a particular earthquake on a building or a community. Often, such scenarios consider the largest earthquake that is believed possible to occur on a fault or fault segment, referred to as the maximum magnitude earthquake (M,„,,). Other scenarios consider the Maximum Probable Earthquake (MPE) or Design Basis Earthquake (DBE) (1997 Uniform Building Code — UBC; 2001 California Building Code - CBC). The DBE is defined as the earthquake with a statistical return period of 475 years (with ground motion that has a 10 percent probability of being exceeded in 50 years). For public schools, hospitals, and other critical facilities, the California Building Code (2001 defines the Upper Bound Earthquake (UBE), which has a statistical return period of 949 years and a ground motion with a 10 percent probability of being exceeded in 100 years. As the descriptions above suggest, which earthquake scenario is most appropriate depends on the application, such as the planned use, expected lifetime of a structure, or importance of a facility. The more critical the structure, the longer the time period used between earthquakes and the larger the design earthquake should be. Seismic design parameters define what kinds of earthquake effects a structure must be able to withstand. These include peak ground acceleration, duration of strong shaking, and the periods of incoming strong motion waves. Geologists, seismologists, engineers, emergency response personnel and urban planners typically use maximum magnitude and maximum probable earthquakes to evaluate seismic hazard. The assumption is that if we plan for the worst -case scenario, we establish Earth Consultants International Seismic Hazards Page 2-10 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . safety margins. Then smaller earthquakes that are more likely to occur can be dealt with effectively. As is true for most earthquake -prone regions, many potential earthquake sources pose a threat to Newport Beach. Thus, it is also important to consider the overall likelihood of damage from a plausible suite of earthquakes. This approach is called probabilistic seismic hazard analysis (PSHA), and typically considers the likelihood of exceeding a certain level of damaging ground motion that could be produced by any or all faults within a 62-mile (100-km) radius of the project site, or in this case, the City. PSHA is utilized by the U.S. Geological Survey to produce national seismic hazard maps that are used by the Uniform Building Code (ICBO, 1997). Regardless of which fault causes a damaging earthquake, there will always be aftershocks. By definition, these are smaller earthquakes that happen close to the mainshock (the biggest earthquake of the sequence) in time and space. These smaller earthquakes occur as the Earth adjusts to the regional stress changes created by the mainshock. As the size of the mainshock increases, there typically is a corresponding increase in the number of aftershocks, the size of the aftershocks, and the size of the area in which they might occur. On average, the largest aftershock will be 1.2 magnitude units less than the mainshock. Thus, a Mw 6.9 earthquake will tend to produce aftershocks up to Mw 5.7 in size. This is an average, and there are many cases where the biggest aftershock is larger than the average predicts. The key point is this: any major earthquake will produce aftershocks • large enough to cause additional damage, especially to already -weakened structures. Consequently, post -disaster response planning must take damaging aftershocks into account. 2.3 Laws To Mitigate Earthquake Hazard 2.3.1 Alquist-Priolo Earthquake Fault Zoning Act The Alquist-Priolo Special Studies Zones Act was signed into law in 1972 (in 1994 it was renamed the Alquist-Priolo Earthquake Fault Zoning Act). The primary purpose of the Act is to mitigate the hazard of fault rupture by prohibiting the location of structures for human occupancy across the trace of an active fault (Hart and Bryant, 1999). This State law was passed in direct response to the 1971 San Fernando earthquake, which was associated with extensive surface fault ruptures that damaged numerous homes, commercial buildings and other structures. Surface rupture is the most easily avoided seismic hazard. The Act requires the State Geologist (Chief of the California Geological Survey) to delineate "Earthquake Fault Zones" along faults that are "sufficiently active" and "well defined." These faults show evidence of Holocene surface displacement along one or more or their segments (sufficiently active) and are clearly detectable by a trained geologist as a physical feature at or just below the ground surface (well defined). The boundary of an "Earthquake Fault Zone" is generally about 500 feet from major active faults, and 200 to 300 feet from well-defined minor faults. The Act dictates that cities and counties withhold development permits for sites within an Earthquake Fault Zone until geologic investigations demonstrate • that the sites are not threatened by surface displacements from future faulting (Hart and Bryant, 1999). Consultants International Seismic Hazards Page 2-11 P1114%] HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The Alquist-Priolo maps are distributed to all affected cities and counties for their use in planning and controlling new or renewed construction. Local agencies must regulate most development projects within the zones. Projects include all land divisions and most structures for human occupancy. State law exempts single-family wood -frame and steel - frame dwellings that are less than three stories and are not part of a development of four units or more. However, local agencies can be more restrictive than State law requires. Alquist-Priolo Earthquake Fault Zone mapping has been completed by the State Geologist for the quadrangle that covers the western part of Newport Beach (Newport Beach quadrangle; CDMG, 1986). This map shows the Alquist-Priolo Earthquake Fault Zone for the Newport -Inglewood fault terminating about two miles northwest of the City limits. Consequently, there are no Alquist-Priolo zones in the City at this time. 2.3.2 Seismic Hazards Mapping Act The Alquist-Priolo Earthquake Fault Zoning Act only addresses the hazard of surface fault rupture and is not directed toward other earthquake hazards. Recognizing this, in 1990, the State passed the Seismic Hazards Mapping Act (SHMA), which addresses non -surface fault rupture earthquake hazards, including strong ground shaking, liquefaction and seismically induced landslides. The California Geological Survey (CGS) is the principal State agency charged with implementing the Act. Pursuant to the SHMA, the CGS is directed to provide local governments with seismic hazard zone maps that identify areas susceptible to liquefaction, and earthquake -induced landslides and other ground failures. The goal is to minimize loss of life and property by identifying and mitigating seismic hazards. The seismic hazard zones delineated by the CGS are referred to as "zones of • required investigation." Site -specific geological hazard investigations are required by the SHMA when construction projects fall within these areas. The CGS, pursuant to the 1990 SHMA, has been releasing seismic hazards maps since 1997. In the Newport Beach area, the CGS has mapped all three quadrangles that encompass the City: Newport Beach, Laguna Beach, and Tustin (CDMG, 1997a, b, c). These maps indicate that liquefaction and earthquake -induced landslides are hazards present locally in the Newport Beach area. 2.3.3 Real Estate Disclosure Requirements Since June 1, 1998, the Natural Hazards Disclosure Act has required that sellers of real property and their agents provide prospective buyers with a "Natural Hazard Disclosure Statement" when the property being sold lies within one or more State -mapped hazard areas. If a property is located in a Seismic Hazard Zone as shown on a map issued by the State Geologist, the seller or the seller's agent must disclose this fact to potential buyers. The law specifies two ways in which this disclosure can be made. One is to use the Natural Hazards Disclosure Statement as provided in Section 1102.6c of the California Civil Code. The other way is to use the Local Option Real Estate Disclosure Statement as provided in Section 1102.6a of the California Civil Code. The Local Option Real Estate Disclosure Statement can be substituted for the Natural Hazards Disclosure Statement only if the Local Option Statement contains substantially the same information and substantially the same warning as the Natural Hazards Disclosure Statement. California State law also requires that when houses built before 1960 are sold, the seller must give the buyer a completed earthquake hazards disclosure report, and a copy of the Earth Consultants International Seismic Hazards Page 2-12 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . booklet entitled "The Homeowner's Guide to Earthquake Safety." This publication was written and adopted by the California Seismic Safety Commission. The most recent edition of this booklet is available from the web at www.seismic.ca.gov/. The booklet contains a sample of a residential earthquake hazards report that buyers are required to fill in, and it provides specific information on common structural weaknesses that can fail, damaging homes during earthquakes. The booklet further describes specific actions that can be taken by homeowners to strengthen their home. The Alquist-Priolo Earthquake Fault Zoning Act and the Seismic Hazards Mapping Act also* require that real estate agents, or sellers of real estate acting without an agent, disclose to prospective buyers that the property is located in an Earthquake Fault or Seismic Hazard Zone. 2.3.4 California Environmental Quality Act The California Environmental Quality Act (CEQA) was passed in 1970 to insure that local governmental agencies consider and review the environmental impacts of development projects within their jurisdictions. CEQA requires that an Environmental Impact Report (EIR) be prepared for projects that may have significant effects on the environment. EIRs are required to identify geologic and seismic hazards, and to recommend potential mitigation measures, thus giving the local agency the authority to regulate private development projects in the early stages of planning. 2.3.5 Uniform Building Code and California Building Code • The International Conference of Building Officials (ICBO) was formed in 1922 to develop a uniform set of building regulations; this led to the publication of the first Uniform Building Code (UBC) in 1927. In keeping with the intent of providing a safe building environment for the community, the technical provisions of the City's building codes have been updated on a regular basis as new editions of the UBC have been published. In addition to updating the regulations concerning fire and life, this has also kept Newport Beach current with the latest provisions for the seismic design of buildings. Recognizing that many building code provisions are not affected by local conditions, like exiting from a building, and to facilitate the concept that industries working in California should have some uniformity in building code provisions throughout the State, in 1980 the legislature amended the State's Health and Safety Code to require local jurisdictions to adopt the latest edition of the Uniform Building Code (UBC). The law states that every local agency, City and County, enforcing building regulations must adopt the provisions of the California Building Code (CBC) within 180 days of its publication. The publication date of the CBC is established by the California Building Standards Commission and the code is known as Title 24 of the California Code of Regulations. Based upon the publication cycle of the UBC, the CBC has been updated and republished every three years since the initial action by the legislature. To further the concept of uniformity in building design, in 1994 the ICBO joined with the two other national building code publishers, the Building Officials and Code Administrators International, Inc. (BOCA) and the Southern Building Code Congress . International, Inc. (SBCCp, to form a single organization, the International Code Council, (ICC). In the year 2000, the group published the first International Building Code (IBC) as Earth Consultants International Seismic Hazards Page 2-13 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • well as an entire family of codes, (i.e. building, mechanical, plumbing and fire) that were coordinated with each other. As a result, the last (and final) version of the UBC was issued in 1997. Since the formation of the ]CC and the publication of the IBC, the California legislature has not addressed the matter of updating the CBC with a building code other than the UBC. Therefore, even though the seismic design provisions have not been brought up to the current standards of the IBC, the California Building Standards Commission, after careful review, has chosen to continue to adopt the old 1997 UBC for the CBC through the 2004 cycle. In addition to adopting the provisions of the CBC, local jurisdiction may adopt more restrictive amendments provided that they are based upon local geographic, topographic or climatic conditions. It should be noted that the Building Codes are the minimum requirements. In some cases these requirements may not adequate, particularly in the area of faulting and seismology, where the pool of knowledge is rapidly growing and evolving. Consequently, it is important that geotechnical consultants working in the City, as well as reviewers of their work, keep up to date on current research. 2.3.6 Unreinforced Masonry Law Enacted in 1986, the Unreinforced Masonry Law (Section 8875 et seq. of the California Government Code) required all cities and counties in Seismic Zone 4 (zones near historically active faults) to identify potentially hazardous unreinforced masonry (URM) • buildings in their jurisdictions, establish a URM loss reduction program, and report their progress to the State by 1990. The owners of such buildings were to be notified of the potential earthquake hazard these buildings pose. The loss reduction program to be implemented, however, was left to each local jurisdiction, although the law recommends that local governments adopt mandatory strengthening programs by ordinance and that they establish seismic retrofit standards. Some jurisdictions did implement mandatory retrofit programs, while others established voluntary programs. A few cities only notified the building owners, but did not adopt any type of strengthening program. The Newport Beach area lies entirely within Seismic Zone 4. Therefore, and in compliance with the Unreinforced Masonry Law, the City inventoried their URMs. In the year 2000, the City reported to the Seismic Safety Commission that 127 URMs had been identified. Of these, only 3 buildings were considered of historical significance. By 2000, all 127 building owners had been notified about the hazards of URM construction, and 125 of the URMs were in compliance with the provisions of the URM Law. One building had been demolished and one more was unoccupied and slated for demolition as of 2000. 2.4 Notable Earthquakes in the Newport Beach Area Figure 2-2 shows the approximate epicenters of earthquakes that have resulted in significant ground shaking in the southern California area, including Newport Beach, since the late 1700s. The most significant of these events are summarized below. Plate 2-1 shows the approximate epicentral locations of historical earthquakes in the study area. The locations and magnitudes of • pre-1932 earthquakes are approximate since there were no instruments available to measure these parameters before 1932. Earth Consultants International Seismic Hazards Page 2-14 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 2.4.1 Unnamed Earthquake of 1769 On July 28, 1769 the first recorded earthquake in southern California was noted by the Spanish explorers traveling north with Gaspar de Portola. At the time of the earthquake, the explorers were camped about 10 miles north of present-day Newport Beach, on the east bank of the Santa Ana River. Father Juan Crespo, who kept a daily account of the expedition, reported a strong mainshock followed by five days of moderate aftershocks; an estimated magnitude of at least 6.0 has been assigned to the event based on the explorers' account (Teggart, 1911). Recent studies of coastal uplift attributed to the earthquake suggest it may have had a magnitude as high as 7.3 and occurred on a blind fault beneath the San Joaquin Hills (Grant et al., 2002). The nearby Elsinore and Newport -Inglewood faults are also considered possible sources for the earthquake. 2.4.2 Unnamed Earthquake of 1800 An earthquake with an estimated magnitude of 6.5 occurred on November 22, 1800 in the coastal region of southern California. Based on the distribution of damage attributed to the earthquake, the epicenter is thought to have been between Newport Beach and San Diego, and was possibly located offshore (Ellsworth, 1990). The earthquake damaged the mission at San Juan Capistrano, located less than 20 miles from present-day Newport Beach and collapsed a barracks in San Diego (www.sfmuseum.org/alm/quakeso.htmi). 2.4.3 Wrightwood Earthquake of December 12, 1812 This large earthquake occurred on December 8, 1812 and was felt throughout southern • California. Based on accounts of damage recorded at missions in the earthquake -affected area, an estimated magnitude of 7.5 has been calculated for the event (Toppozada et al., 1981). Subsurface investigations and tree ring studies show that the earthquake likely ruptured the Mojave Section of the San Andreas fault near Wrightwood, and may have been accompanied by a significant surface rupture between Cajon Pass and Tejon Pass (Jacoby, Sheppard and Sieh, 1988; www.scecdc.scec.org/quakedex.html). The worst damage caused by the earthquake occurred significantly west of the San Andreas fault at San Juan Capistrano Mission, where the roof of the church collapsed, killing 40 people. The earthquake also damaged walls and destroyed statues at San Gabriel Mission and damaged missions in the Santa Barbara area. Strong aftershocks caused earthquake - damaged buildings to collapse for several days after the mainshock. 2.4.4 Unnamed Earthquake of December 21, 1812 The Wrightwood earthquake was followed by a strong earthquake on December 21" that caused widespread damage in the Santa Barbara area. The effects of this second earthquake are sometimes attributed to the December 121n event, giving the impression that a single large earthquake caused significant damage from Santa Barbara to San Diego. The second earthquake had an estimated magnitude of 7 and was likely located offshore within the Santa Barbara Channel, although it could have occurred inland in Santa Barbara or Ventura Counties (www.scecdc.scec.org/quakedex.htmi). The earthquake destroyed the church at the Mission in Santa Barbara, the Mission de Purisima Concepcion near present day Lompoc, and the Mission at Santa Inez (www.johnmartin.com/eqs/00000077.htm). The earthquake also caused a tsunami that may have traveled up to 1/2 mile inland near . Santa Barbara (see Chapter 1 — Coastal Hazards). Earth Consultants International Seismic Hazards Page 2-15 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 2.4.5 Unnamed Earthquake of 1855 This earthquake occurred on July 11, 1855 and was felt across southern California from Santa Barbara to San Bernardino. Light to moderate damage was reported in the Los Angeles area, where 26 houses experienced cracked walls and the bell tower of the San Gabriel Mission was knocked down(www.sfmuseum.org/alm/quakeso.html). Because damage was limited primarily to the Los Angeles area, this earthquake is postulated to have occurred on a local fault such as the Hollywood -Raymond, Whittier or Newport - Inglewood faults, or on one of the many blind thrust faults in the area. 2.4.6 San Jacinto Earthquake of 1899 This earthquake occurred at 4:25 in the morning on Christmas Day, in 1899. The main shock is estimated to have had a magnitude of 6.5. Several smaller aftershocks followed the main shock, and in the town of San Jacinto, as many as thirty smaller tremors were felt throughout the day. The epicenter of this earthquake is not well located, but damage patterns suggest the location shown on Figure 2-2, near the town of San Jacinto, with the causative fault most likely being the San Jacinto fault. Both the towns of San Jacinto and Hemet reported extensive damage, with nearly all brick buildings either badly damaged or destroyed. Six people were killed in the Soboba Indian Reservation as a result of falling adobe walls. In Riverside, chimneys toppled and walls cracked (Claypole, 1900). The main earthquake was felt over a broad area that included San Diego to the southwest, Needles to the northeast, and Arizona to the east. No surface rupture was reported, but several large "sinks" or subsidence areas were reported about 10 miles to the southeast of San Jacinto. • 2.4.7 Elsinore Earthquake of 1910 This magnitude 6 earthquake occurred on May 15, 1910 at 7:47 A.M. Pacific Standard Time, following two moderate tremors that occurred on April 10 and May 12, 1910. The Elsinore fault is thought to have caused the earthquake, although no surface rupture along this fault was reported. Damage as a result of this earthquake was minor; toppled chimneys were reported in the Corona, Temescal and Wildomar areas. The epicentral location of this earthquake is very poorly defined. 2.4.8 San Jacinto Earthquake of 1918 The magnitude 6.8 San Jacinto earthquake occurred on April 21, 1918 at 2:32 P.M. Pacific Standard Time, near the town of San Jacinto. The earthquake caused extensive damage to the business districts of San Jacinto and Hemet, where many masonry structures collapsed, but because it occurred on a Sunday, when these businesses were closed, the number of fatalities and injuries was low. Several people were injured, but only one death was reported. Minor damage as a result of this earthquake was reported outside the San Jacinto area, and the earthquake was felt as far away as Taft (west of Bakersfield), Seligman (Arizona), and Baja California. Earth Consultants International Seismic Hazards Page 2-16 2003 • • • • •r I • /�I • : 311111933 • Mw 6A 75 mI 3/11/1933 Mw5.2 NOTES: • This map is intended for general land use planning only. Information on this map is not sufficient to serve as a substitute for detailed geologic Investigations of Individual sites, nor does It satisfy the evaluation requirements set forth in geologic hazard regulations. Earth consultants International (ECI) makes no representations or warranties regarding the accuracy of the data from which these maps were derived. ECI shell not be liable under any circumstances for any direct, indirect, special, incidental, or consequential damages with respect to any claim by any user or third party on account of, m arising from, the use of this map. Ll r. Historical Seismicity • (1855-2002) r. A x i ,� a r • Newport Beach, California EXPLANATION • • n / J D A !1 1 N Earthquake Magnitude i 5 to 6.4 4to5 3to4 . 2to3 • 1to2 ® Newport Beach City Boundary Sphere of Influence Scale: 1:60,000 0.5 0 0.5 1 LS Miles 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from SureIMAPS RASTER Sources: Southern California Earthquake Center (January 1932 to August 22, 2002); National Earthquake Information Center (1855 to 1931). Tim Earth ' Consultants International Project Number: 2112 Date: July, 2003 Plate 2-1 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Strong shaking cracked the ground, concrete roads, and concrete irrigating canals, but none of the cracks are thought to have been caused directly by surface fault rupture. The shaking also triggered several landslides in mountain areas. The road from Hemet to Idyllwild was blocked in several places where huge boulders rolled down slopes. Two men in an automobile were reportedly swept off a road by a landslide, and would have rolled several hundred feet down a hillside had they not been stopped by a large tree. Two miners were trapped in a mine near Winchester, but they were eventually rescued, uninjured. The earthquake apparently caused changes in the flow rates and temperatures of several springs. Sand craters (due most likely to liquefaction) were reported on one farm, and an area near Blackburn Ranch "sunk" approximately three feet (one meter) during the quake (/www.scecdc.scec.org/quakedex.html). 2.4.9 1933 Long Beach Earthquake The Mw 6.4 Long Beach earthquake occurred on March 10, at 5:54 P.M. Pacific Standard Time, following a strong foreshock the day before. The earthquake ruptured the Newport - Inglewood fault, and was felt from the San Joaquin Valley to Northern Baja. The epicenter was located on the boundary between Huntington Beach and Newport Beach, although the earthquake was called "The Long Beach Earthquake" because the worst damage was focused in the city of Long Beach. in the Newport Beach area, the earthquake produced Modified Mercalli Intensities of VII-VIII (http://pasadena.wr.usgs.gov/shake/ca/). The earthquake killed 115 people and caused $40-50 million in property damage (www.scecdc.scec.org/quakedex.html). Primary ground rupture of the Newport -Inglewood fault was not observed, although secondary cracking, minor slumping, and lateral • movement of unconsolidated sediments occurred throughout the region. Road surfaces along the shore between Long Beach and Newport Beach were damaged by settlement of road fills that had been placed on marshy land. In urban areas, unreinforced masonry buildings were most severely damaged, especially in areas of artificial fill or water -soaked alluvium. In one part of Compton, most buildings built on unconsolidated sediments and artificial fill were destroyed. In Long Beach, many buildings collapsed, were pushed off their foundations, or had walls or chimneys knocked down. In Newport Beach, 800 chimneys were knocked down at the roofline and hundreds of houses were destroyed (www.anaheimcocom.com/quake.htm). Damage to school buildings was especially severe and led to the passage of the Field and Riley Acts by the State legislature. The Field Act regulates school construction and the Riley Act regulates the construction of buildings larger than two-family dwellings. Many strong aftershocks occurred through March 161h. 2.4.10 Torrance -Gardena Earthquakes of 1941 In 1941, two small earthquakes struck the southern Los Angeles basin, affecting surrounding communities. Although these earthquakes were relatively minor, they occurred close to the surface and caused significant, although localized damage. The magnitude 4.8 Torrance earthquake occurred on October 21" at 10:57 P.M., Pacific Standard Time and was located east of Carson near the present-day interchange of the 405 and 710 freeways. Shaking up to intensity level VII was reported in the communities of Wilmington, Gardena, Lynwood, Hynes and Signal Hill where walls were cracked and chimneys damaged. In some cases, houses that had not been adequately repaired after the 1933 Long Beach earthquake were damaged again (www.johnmartin.com/egpapers/00000077.htm). No injuries were reported and damage estimates totaled $100,000 (www.scecdc.scec.org/quakedex.htmi). Earth Consultants International Seismic Hazards Page 2-18 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • A second earthquake occurred less than a month later, on November 14 at 12:42 A.M. Pacific Standard Time, near Wilmington. Shaking during the second earthquake was reportedly stronger than the first, locally reaching intensity level VIII (Table 2-1) and felt as far away as Cabazon, Carpinteria, and San Diego. Gas and water mains burst near the epicenter and storefronts in the business districts of Torrance and Gardena collapsed, crushing parked cars. Damage to local oilfields was significant - well casings and equipment were damaged and a 55,000 gallon oil tank ruptured, flooding nearby streets with oil. Production of several wells was lowered or stopped. No injuries were reported; although damage attributed to the second event totaled one million dollars. (www.scecdc.scec.org/quakedex.html). 2.4.11 San Jacinto Fault Earthquake of 1954 This MW 6.4 earthquake occurred on March 19, 1954, at 1:54 A.M. Pacific Standard Time, on the Clark fault segment of the San Jacinto fault, about 30 miles south of Indio. It caused minor damage throughout southern California including cracked plaster walls in San Diego and falling ceiling plaster at Los Angeles City Hall. In the Palm Springs area, a water pipe was damaged and the walls of several swimming pools were cracked. Parts of San Bernardino experienced temporary blackouts because the shaking caused power lines to snap. The earthquake was felt as far away as Ventura County, Baja California, and Las Vegas. 2.4.12 Borrego Mountain Earthquake of 1968 This M, 6.5 earthquake occurred on the evening of April 8, 1968 at 6:29 P.M. Pacific • Standard Time. The epicenter was located about 40 miles south of Indio on the Coyote Creek fault, which is a branch of the San Jacinto fault. The earthquake was felt throughout southern California, and as far away as Las Vegas, Fresno and the Yosemite Valley. The earthquake produced minor surface rupture near Ocotillo Wells and triggered minor slip on the Superstition Hills, Imperial and Banning -Mission Creek faults (www.scecdc.scec.org/quakedex.htm]). Damage was reported throughout southern California, most notably in the Imperial Valley, where several buildings collapsed, and in Anza-Borrego Desert State Park where landslides damaged several vehicles. The earthquake also severed power lines in San Diego, knocked plaster from ceilings in Los Angeles, and the Queen Mary II, which was dry-docked at Long Beach, rocked back and forth on its keel blocks for five minutes. No injuries were reported. 2.4.13 San Fernando (Sylmar) Earthquake of 1971 This magnitude 6.6 earthquake occurred on the San Fernando fault zone, the westernmost segment of the Sierra Madre fault, on February 9, 1971, at 6:00 in the morning. The surface rupture caused by this earthquake was nearly 12 miles long, and occurred in the Sylmar -San Fernando area, approximately 55 miles (88 km) northwest of Newport Beach. The maximum slip measured at the surface was nearly six feet. The earthquake caused over $500 million in property damage and 65 deaths. Most of the deaths occurred when the Veteran's Administration Hospital collapsed. Several other hospitals, including the Olive View Community Hospital in Sylmar suffered severe damage. Newly constructed freeway overpasses also collapsed, in damage scenes similar to those that occurred 23 years later in the 1994 Northridge earthquake. Loss of life could have been much greater • had the earthquake struck at the busier time of the day. As with the Long Beach earthquake, legislation was passed in response to the damage caused by the 1971 Earth Consultants International Seismic Hazards Page 2-19 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • earthquake. In this case, the building codes were strengthened and the Alquist-Priolo Special Studies (now call the Earthquake Fault Zone) Act was passed in 1972. 2.4.14 Oceanside Earthquake of 1986 This magnitude 5.4 earthquake occurred on the morning of July 13, 1986 at 6:47 A.M. Pacific Daylight Time. The epicenter was about 32 miles offshore from Oceanside and occurred on an unidentified fault that may be related to the San Diego Trough or the Palos Verdes -Coronado Bank fault zones (www.scecdc.scec.org/quakedex.html). One death and at least 29 injuries are attributed to this relatively small earthquake, which was felt throughout the coastal communities of southern California. At least 50 buildings were damaged from Newport Beach to San Diego, with damage estimates totaling nearly one million dollars. 2.4.15 Whittier Narrows Earthquake of 1987 The Whittier Narrows earthquake occurred on October 1, 1987, at 7:42 in the morning, with its epicenter located approximately 27 miles (43 km) northwest of Newport Beach (Hauksson and Jones, 1989). This magnitude 5.9 earthquake occurred on a previously unknown, north -dipping concealed thrust fault (blind thrust) now called the Puente Hills fault (Shaw and Shearer, 1999). The earthquake caused eight fatalities, over 900 injured, and $358 million in property damage. Severe damage was confined mainly to communities east of Los Angeles and near the epicenter. Areas with high concentrations of URMs, such as the "uptown" district of Whittier, the old downtown section of Alhambra, and the "Old Town" section of Pasadena, were severely impacted. Several tilt -up • buildings partially collapsed, including tilt -up buildings built after 1971, that were built to meet improved building standards, but were of irregular configuration, revealing seismic vulnerabilities not previously recognized. Residences that sustained damage usually were constructed of masonry, were not fully anchored to their foundations, or were houses built over garages with large openings. Many chimneys collapsed and in some cases, fell through roofs. Wood -frame residences, in contrast, sustained relatively little damage, and no severe structural damage to high-rise structures in downtown Los Angeles was reported. 2.4.16 Newport Beach Earthquake of 1989 A small, magnitude 4.7 earthquake struck the City of Newport Beach at 1:07 P.M. Pacific Daylight Time on April 7, 1989 (www.scecdc.scec.org/quakedex.htmi). The earthquake did not rupture the surface or cause any significant damage, but was notable because it occurred on the Newport -Inglewood fault system directly below the city of Newport Beach. 2.4.17 Landers Earthquake of 1992 On the morning of June 28, 1992, most people in southern California were awakened at 4:57 by the largest earthquake to strike California in 40 years. Named "Landers" after a small desert community near its epicenter, the earthquake had a magnitude of 7.3. More than 50 miles of surface rupture associated with five or more faults occurred as a result of this earthquake. The average right -lateral strike -slip displacement was about 10 to 15 feet, while a maximum of up to 18 feet was observed. Centered in the Mojave Desert, approximately 120 miles from Los Angeles, the earthquake caused relatively little damage • for its size (Brewer, 1992). It released about four times as much energy as the very destructive Loma Prieta earthquake of 1989, but fortunately, it did not claim as many lives Consultants International Seismic Hazards Page 2-20 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • (one child died when a chimney collapsed). The power of the earthquake was illustrated by the length of the ground rupture it left behind. The earthquake ruptured five separate faults: Johnson Valley, Landers, Homestead Valley, Emerson, and Camp Rock faults (Sieh, 1992). Other nearby faults also experienced triggered slip and minor surface rupture. Modified Mercalli Intensities of III were reported in the Newport Beach area as a result of this earthquake (Iittp://i)asadena.wr.usgs.gov/shake/cad. 2.4.18 Northridge Earthquake of 1994 On the morning of January 17"', 1994, at 4:31 Pacific Standard Time, a M. 6.7 earthquake struck the San Fernando Valley. This moderate -sized tremor was the most expensive earthquake in United States history, due primarily to its proximity to the heavily populated northern Los Angeles area. The rupture occurred in the San Fernando Valley on the previously unidentified eastern continuation of the Oak Ridge fault, which is a blind thrust fault and thus does not break the surface. The earthquake produced widespread ground accelerations of 1.0 g, some of the highest ever recorded for an earthquake of its size. The earthquake caused 57 deaths, 1,500 injuries and damaged 12,500 structures, knocking several major freeways out commission for days to months. Although most damage was focused in the northern Los Angeles area, intensities of V-VI (Table 2-1) were recorded in the Newport Beach area, causing scattered light to moderate damage. 2.4.19 Hector Mine Earthquake of 1999 Southern California's most recent large earthquake was a widely felt magnitude 7.1. It occurred on October 18, 1999, in a remote region of the Mojave Desert, 47 miles east- southeast of Barstow. Modified Mercalli Intensities of IV (Table 2-1) were reported in the Newport Beach area (http•1/Pasadena.wr.uses.gov/shake/cad. The Hector Mine earthquake is not considered an aftershock of the M 7.3 Landers earthquake of 1992, although Hector Mine occurred on similar, north-northwest trending strike -slip faults within the Eastern Mojave Shear Zone. Geologists documented a 25-mile (40-km) long surface rupture and a maximum right -lateral strike -slip offset of about 16 feet on the Lavic Lake fault. 2.5 Potential Sources of Seismic Ground Shaking Seismic shaking is the geologic hazard that has the greatest potential to severely impact the Newport Beach area, given that the city is located on and near several significant seismic sources (faults) that have the potential to cause moderate to large earthquakes (see Table 2-2). As discussed in Section 2.4 above, some of these faults caused moderate -sized earthquakes in the last century; however, given their length, they are thought capable of generating even larger earthquakes in the future that would cause strong ground shaking in Newport Beach and nearby communities. The proximity of Newport Beach to these and other regionally more significant seismic sources should encourage the City of Newport Beach to diligently attend to seismic hazard mitigation. In order to provide a better understanding of the shaking hazard posed by these faults, a deterministic seismic hazard analysis using industry standard software [EQFAULT, by Blake (2000a)] was performed. This analysis estimates the Peak Horizontal Ground Accelerations (PHGA) that could be expected at City Hall due to earthquakes occurring on any of the known active or potentially active faults within 62 miles (100 km). A probabilistic seismic hazard analysis using FRISKSP (Blake, 2000b) to estimate the median PHGA at City Hall was also conducted. The Earth Consultants International Seismic Hazards Page 2-21 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • difference between these two approaches is that, while a deterministic hazard assessment addresses individual sources or scenario events, probabilistic assessments combine all seismic sources and consider the likelihood (or probability) of each source to generate an earthquake. In a probabilistic analysis, a mathematical equation is used to estimate the combined risk posed by all known faults within 62 miles (100 km), and for each fault, a suite of possible damaging earthquakes is considered, each weighed according to its likelihood of occurring in any particular year. The fault database (including fault locations and earthquake magnitudes of the maximum magnitude and maximum probable earthquakes for each fault) used to conduct these seismic shaking analyses is that used by the California Geological Survey (CGS) and the US Geological Survey (USGS) for the National Seismic Hazard Maps (Peterson and others, 1996). PGHA depends on the size of the earthquake, the proximity of the rupturing fault, and local soil conditions. Effects of soil conditions are estimated by use of an attenuation relationship. To develop such a relationship, scientists analyze recordings of earthquake shaking on similar soils during earthquakes of various sizes and distances. The PHGA estimates obtained from these analyses provide a general indication of relative earthquake risk in the city of Newport Beach. For individual projects however, site -specific analyses that consider the precise distance from a given site to the various faults in the region, as well as the local near -surface soil types, should be conducted. Newport Beach City Hall is built on soft, unconsolidated estuarine deposits, which can greatly amplify earthquake shaking. To quantify the degree of amplification, velocity measurements of • earthquake shear -waves and other site -specific sub -surface analyses would be needed. However, to illustrate the effects of soil type at City Hall, the attenuation relationships of Boore and others (1997) were used to provide two PGHA estimates, one for soil with a near -surface shear -wave velocity of 250 meters per second (m/s); the other for a velocity of 150 m/s. The former velocity produces deterministic estimates of maximum PGHA around 0.58g. The second velocity yields a maximum PGHA of around 0.7g. Shaking at these levels can cause heavy damage even to newer buildings that are constructed with more stringent building standards than older structures. Based on the ground shaking analyses described above, those faults that can cause peak horizontal ground accelerations of about 0.1 g or greater (Modified Mercalli Intensities greater than VII) in the Newport Beach area are listed in Table 2-2. For a map showing most of these faults, refer to Figure 2-1. Those faults included in Table 2-2 that have the greatest impact on the Newport Beach area, or that are thought to have a higher probability of causing an earthquake, are described in more detail in the following pages. The locations of active faults nearby to the City are shown of Figure 2-3. Table 2-2 shows: The distance, in kilometers and miles, between the fault and the Newport Beach City Hall; The maximum magnitude earthquake (Mm,n) each fault is estimated capable of generating; The peak ground acceleration (PGA), or intensity of ground motion expressed as a fraction of the acceleration of gravity (g), that could be experienced in the Newport Beach Area if the Mm,x occurs on one of these faults; and • The Modified Mercalli seismic Intensity (MMI) values calculated for the City. Earth Consultants International Seismic Hazards Page 2-22 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • In general, peak ground accelerations and seismic intensity values decrease with increasing distance away from the causative fault. However, local site conditions, such as ridge tops, could amplify the seismic waves generated by an earthquake, resulting in localized higher accelerations than those listed here. The strong ground motion values presented here should therefore be considered as average values; higher values may occur locally in response to site -specific conditions. The M,,, reported here are based on the fault parameters published by the CGS (CDMG, 1996). The peak ground accelerations reported above were calculated using EQFAULT (Blake, 2000a), a software package that uses the CGS fault data and provides several peer -reviewed earthquake attenuation equations. However, as described further in the text, recent paleoseismic studies suggest that some of these faults, like the Whittier fault, can actually generate even larger earthquakes than those used in the table above. Furthermore, the CGS fault database does not yet include the San Joaquin Hills thrust fault that was recently proposed to underlie a large portion of Newport Beach. This fault, by its location relative to the City (see Figure 2-3), and its type (blind thrust fault) has the potential to generate even stronger ground shaking in Newport Beach than any of the faults that were used in the probabilistic and deterministic analyses reported herein. For additional data regarding the seismic hazard posed by this fault, refer to Sections 2.5.2 and 2.9.4. The probabilistic PGHA values calculated for City Hall using the two different local soil conditions are 0.43 and 0.52g. In other words, the Newport Beach area has a 10 percent chance of experiencing ground accelerations greater than 43 to 52 percent the force of gravity in 50 years. These probabilistic ground motion values for the City of Newport Beach are in the high to very (� • high range for southern California, and are the result of the City's proximity to major fault systems t— with high earthquake recurrence rates. These levels of shaking can be expected to cause damage, particularly to older and poorly constructed buildings. • Differences between deterministic and probabilistic PGHA at this site are due to the long recurrence intervals of many of the faults in the analysis. Faults which cause damaging earthquakes at less frequent intervals yield a lower annual likelihood of a damaging earthquake, and thus a lower probabilistic hazard value when considering relatively short time periods such as the 475 years of this analysis. Since we do not know when the clock started ticking for most of these faults (i.e., when the last earthquake occurred, nor how close to failure the fault is today), the City cannot take comfort in the lower yearly likelihood of damage, but must be prepared for shaking of at least 0.7g. Earth Consultants International Seismic Hazards Page 2-23 2003 • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Table 2-2 Estimated Horizontal Peak Ground Accelerations and Seismic Intensities in the Newport Beach Area Fault Name Distance to Newport Beach (km) Distance to Newport Beach (mi) Magnitude of Mm. * PGA (g) from M. MMI from Mmax Newport -Inglewood (LA Basin) 0.5 0.3 6.9 0.70 XI Newport -Inglewood (Offshore) 3.1 1.9 6.9 0.64 X Compton Thrust 14.3 9.0 6.8 0.37 IX Palos Verdes 19.3 12.0 7.1 0.29 IX Elysian Park Thrust 25.7 16.0 6.7 0.23 IX Chino -Central Ave. (Elsinore) 33.6 20.9 6.7 0.19 VIII Whittier 34.8 21.6 6.8 0.16 VIII Elsinore -Glen Ivy 37.8 23.5 6.8 0.15 VIII Coronado Bank 38.7 24.0 7.4 0.20 VIII San Jose 47.2 29.3 6.5 0.13 VIII Elsinore -Temecula 53.9 33.5 6.8 0.11 VII Sierra Madre 58.3 36.2 7.0 0.15 VIII Cucamonga 59.5 37.0 7.0 0.14 VIII Raymond 59.8 37.2 6.5 0.11 VII Verdugo 60.9 37.8 6.7 0.12 VII Hollywood 62.5 38.8 6.4 0.10 VII Clamshell-Sawpit 62.7 39.0 6.5 0.11 VII Santa Monica 68.1 42.3 6.6 1 0.10 VII Rose Canyon 71.5 44A 6.9 0.10 VII Malibu Coast 72A 45.0 6.7 0.11 VII Northridge (E. Oak Ridge) 78.6 48.8 6.9 0.11 VII Sierra Madre (San Fernando) 81.0 50.3 6.7 0.10 VII Anacapa-Dume 81.9 50.9 7.3 0.13 XII San Andreas - Southern 85.1 52.9 7.4 0.11 VII San Andreas -San Bernardino 85.1 52.9 7.3 0.10 VII San Andreas -1857 Rupture 85.6 53.2 7.8 0.14 VIII Abbreviations used in Table 2-2: mi - miles; km - kilometer; M. - maximum magnitude earthquake; PGA - peak ground acceleration as a percentage of & the acceleration of gravity; MMI - Modified Mercalli Intensity. • Earth Consultants International Seismic Hazards Page 2-24 2003 • 0 -"Sierra Fault ' !'f\Cuc� L Allo�,eSF — of Los Angeles /- San Bernardino CountyZ County ti ✓ =� i ?foA� .. cl ri, Riverside County Orange County °?y City of I i- ?9�Q Newport Leach 1, co '-mod �'' .- `•:-,�:;;,•,, alcilfic, �+ 1 „ San Diego, T County Modified from: Shaw atal.,2002;Dolan, Shaw, and Pratt, 2001; and Jennings, 1995 Map Explanation Blind thrust fault ramp; red hatchures show surface projection or upper edge of thrust ramp, the thrust fault ramps are shown from deepest to shallowest by gray and green shading, respectively. �-- Fault Showing Evidence of Historic Rupture (Active). /"— Fault Showing Evidence of Holocene Rupture (Active). .l Fault Showing Evidence of Quaternary and Late Quaternary Rupture (Potentially 3 Earl' w- consunluland Local Active and Potentially Figure Project Number 2112 Active Faults 2-3 Date: March, 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 2.5.1 Newport -Inglewood Fault Zone The northwest -trending Newport -Inglewood fault zone (NIFZ) is 145 miles long and extends from Santa Monica south to Newport Beach. At Newport Beach, the fault continues offshore and lines up with a deep submarine canyon (Fischer and Mills, 1991) known as the Newport Submarine Canyon. The offshore segment of the fault joins the Rose Canyon fault, which extends southeasterly through San Diego to the international border. The Newport -Inglewood fault zone is discontinuous, consisting of a series of left -stepping en echelon fault strands up to 4 miles long. Onshore, the fault zone is marked by a series of uplifts and anticlines including Newport Mesa, Huntington Mesa, Bolsa Chica Mesa, Alamitos Heights and Landing Hill, Signal Hill and Reservoir Hill, Dominguez Hills, Rosecrans Hills, and Baldwin Hills (Barrows, 1974). These anticlines are traps for oil and have been drilled successfully since the beginning of the last century. The NIFZ extends across the westernmost portion of Newport Beach (see Figure 2-3 and Plate 2-2). In this area, the fault zone is over 1.5 miles wide and consists of many discontinuous primary fault stands and several short secondary fault traces. Several studies in the Newport Beach area have identified multiple strands of the NIFZ that have displaced Holocene -age terraces and sediments (Converse Consultants, 1994; Shlemon et al., 1995; Grant et al., 1997; Earth Consultants International, 1997). The slip rate for the NIFZ is poorly constrained at between 0.3 to 3.5 mm/yr. A study by Woodward -Clyde Consultants in 1979 calculated a slip rate of 0.5 mm/yr for the southern onshore segment of the NIFZ. This is consistent with long-term slip rates of 0.31 — 0.52 mm/yr calculated by Freeman et al. (1992) by correlating stratigraphy on one side of the fault to a best match on the opposite side of the fault. More recent paleoseismic studies by Grant et al. (1997) also suggest a slip rate of between 0.34 to 0.55 mm/yr for the onshore segment. Fischer and Mills (1991) estimated a slightly higher slip rate of between 1.3 and 3.5 mm/yr for the offshore segment of the NIFZ between San Mateo Point and Newport Beach with an earthquake recurrence interval of between 200 and 800 years. Lindvall and Rockwell (1995) calculated a maximum slip rate of 2 mm/yr for the Rose Canyon fault, the southern continuation of the NIFZ. Paleoseismic studies by Grant et al. (1997) and Shlemon et al. (1995) have shown that the onshore segment of the NIFZ has had three to five ground rupturing earthquakes in the last 11,700 (+/-700 years). This is consistent with the recurrence interval calculated by Fischer and Mills (1991) for the offshore segment of the NIFZ. The last significant earthquake on the NIFZ was the magnitude 6.3 Long Beach earthquake. This earthquake did not break the ground surface. PGHA calculations suggest that Newport Beach has a ten percent chance of experiencing ground accelerations exceeding between 0.29g and 0.52g in the next 50 years. These values were calculated for ten locations around the Newport Beach area that are representative of the area as a whole, and reflect the fact that some areas of Newport Beach are farther away from the regional faults than others. These estimates are also a statistical average that take into account earthquakes on all faults in the region, and include an assessment of the probability of an earthquake occurring on each of the faults • considered. A deterministic analysis, on the other hand, indicates that a maximum earthquake of magnitude 6.9 on the onshore segment of the NIFZ has the potential to Earth Consultants International Seismic Hazards Page 2-26 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . generate stronger ground motions with peak horizontal ground accelerations of between 0.58g and 0.71g in the Newport Beach area. Similarly, a 6.9 earthquake on the offshore segment of the NIFZ could generate peak horizontal ground acceleration in the Newport Beach area of between 0.53g and 0.64g. • 2.5.2 San Joaquin Hills Fault Analysis of uplifted marine terraces between Huntington Beach and San Juan Capistrano suggests the presence of a southwest -dipping blind thrust beneath the San Joaquin Hills (see Figure 2-3), adjacent to the Newport -Inglewood fault zone (Grant et al., 1999). Based on structural modeling of dated marine terraces, Grant et al. (1999) calculated a slip rate of about 0.42-0.79 mm/yr and a minimum average recurrence interval of about 1,600 to 3,100 years for moderate size earthquakes on this fault. Uplift of late Holocene shorelines and marsh deposits above the active shoreline are attributed to a relatively recent earthquake larger than magnitude 7 on the San Joaquin Hills fault (Grant et al., 2002). Radiocarbon dating and pollen analyses suggest this earthquake occurred between 1635 and 1855 AD. Rivero et al. (2000) consider this fault to be part of a larger structure that extends offshore to the south. This fault is not yet included in the CGS fault database used for shaking analyses, however a moderate earthquake on this fault would cause significant peak horizontal ground accelerations in the City, stronger than those caused by any of the other faults considered. An earthquake on the San Joaquin Hills faults is therefore the worst -case scenario for Newport Beach. This is illustrated further in Section 2.9.4. 2.5.3 Palos Verdes Fault Zone The 80 to 115 km -long Palos Verdes fault zone is located primarily offshore and extends in a southeasterly direction from Santa Monica Harbor to the southern San Pedro Channel (Figure 2-1). The short onshore segment of the fault extends for nine miles (15 km) from Redondo Beach to San Pedro and follows the northeastern flank of the Palos Verdes Hills. Offshore, to the southeast, the fault trends across Los Angeles Harbor, and onto the continental shelf where it splays into two discontinuous sub -parallel strands and continues southeast as the Coronado Bank fault zone. Northwest of Redondo Beach, the fault is thought to end in a horsetail splay in Santa Monica Bay, although some scientists suggest the fault continues northwesterly and joins the Dume fault (Stephenson et al., 1995). The fault is located about 12 miles west of Newport Beach at its nearest point. Davis et al. (1989) and Shaw and Suppe (1994) modeled the Palos Verdes fault as a southwest -dipping back thrust above a blind thrust. Calculated vertical rates of deformation for the fault based on uplifted marine terraces range from 0.2 to 0.7 mm/yr (Clarke et al., 1985) to 3 mm/yr (Ward and Valensise, 1994). Recent geomorphic studies, however, indicate the fault has a significant right lateral component. McNeilan et al. (1996) used an offset channel in the Los Angeles Harbor to derive a right -lateral slip rate of 3 mm/yr. Based on its length and uplift rate, the Palos Verdes fault could produce an earthquake of magnitude 7.1 and cause peak horizontal ground accelerations of 0.24g to 0.29g in Newport Beach. Earth Consultants International Seismic Hazards Page 2-27 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . 2.5.4 Coronado Bank Fault The 55-mile (90 —km) long offshore Coronado Bank fault zone is the principal southern continuation of the Palos Verdes fault, extending from the southeast flank of the Lausen Knoll in the southern San Pedro Channel (about 24 miles south of Newport Beach) to the La Jolla submarine channel. Bathymetric data show that the fault is well defined by alternating pop-up structures and broad transtensional sags (Legg, 1985; Legg and Kennedy; 1991; M. Legg and C. Goldfinger, 2001). Right lateral motion has been inferred from uplift at left bends in the fault trace and sags at right bends. Little is known about the slip rate or return time of large events on the fault, although a roughly estimated slip rate of 2-3 mm/yr for the Coronado Bank fault zone is based on rates derived on the offshore segment of the Palos Verdes fault. The Coronado Bank fault zone could rupture together with the Palos Verdes fault, producing a magnitude 7.4 earthquake, that would result in peak ground accelerations in Newport Beach of about 0.2g. 2.5.5 Compton Thrust Fault The Compton Thrust fault is an inferred blind thrust fault in the southwestern portion of the Los Angeles basin. The fault is part of the Compton -Los Alamitos fault system, postulated to extend over 50 miles from Western Santa Monica Bay southeast into northwestern Orange County. Little is known about this fault because it does not break the surface. However, Shaw and Suppe (1996) calculated a slip rate of 1.4 +/- 0.4 mm/yr based on modeling of deep seismic data. More recently, Mueller (1997) showed that geologic structures and units overlying the fault are not deformed, including a 1,900 year -old peat deposit and a 15,000 to 20,000 year -old aquifer, indicating that the fault may not be . active. Nevertheless, the fault databases still include the Compton thrust as a potential seismic source. If the fault is active, it has the potential to generate a magnitude 6.8 earthquake that would cause peak horizontal ground accelerations of between 0.30g and 0.37g in the city of Newport Beach. An event of this size has an estimated average recurrence interval of 676 years based on the 1.4 mm/yr slip rate. 2.5.6 Elysian Park Thrust The Whittier Narrows earthquake of October 1, 1987 occurred on a previously unknown blind thrust fault underneath the eastern part of the Los Angeles basin. Davis et al. (1989) used oil field data to construct cross -sections showing the subsurface geology of the basin, and concluded that the Whittier Narrows earthquake occurred on a 12- to 24-mile (20 to 38-km) long thrust ramp they called the Elysian Park thrust fault. They modeled the Elysian Park as a shallow -angle, reverse fault 6 to 10 miles below the ground surface, generally located between the Whittier fault to the southeast and the Hollywood fault to the west- northwest. Although blind thrusts do not extend to the Earth's surface, they are typically expressed at the surface by a series of hills or mountains. Davis et al. (1989) indicated that the Elysian Park thrust ramp is expressed at the surface by the Santa Monica Mountains, and the Elysian, Repetto, Montebello and Puente Hills. Davis et al. 0989) estimated a long-term slip rate on the Elysian Park fault of between 2.5 and 5.2 mm/yr. Dolan et al. (1995) used a different approach to estimate a slip rate on the Elysian Park fault, arriving at a rate of about 1.7 mm/yr with a recurrence interval of about 1,475 years. In 1996, Shaw and Suppe re -interpreted the subsurface geology of the Los . Angeles basin and proposed a new model for what they call the Elysian Park trend. They estimated a slip rate on the thrust ramp beneath the Elysian Park trend of 1.7t0.4 mm/yr. Earth Consultants International Seismic Hazards Page 2-28 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • More recently, Shaw and Shearer (1999) relocated the main shock and aftershocks of the 1987 Whittier Narrows earthquake, and showed that the earthquake sequence occurred on an east -west trending buried thrust they called the Puente Hills thrust (rather than the northwest -trending Elysian Park thrust). Given the enormous amount of research currently underway to better characterize the blind thrust faults that underlie the Los Angeles basin, the Elysian Park thrust fault will most likely undergo additional significant re -interpretations. In fact, Shaw and Shearer (1999) suggest that the Elysian Park thrust fault is no longer active. However, since this statement is under consideration, and the Elysian Park thrust is still part of the active fault database for southern California (CDMG, 1996), this fault is still considered to be a potential seismic source that can affect the region. If this fault caused a magnitude 6.7 earthquake, it is estimated that Newport Beach would experience peak ground accelerations of about 0.23g. 2.5.7 Elsinore Fault Zone The 125-mile (200 —km) long Elsinore fault is part of the San Andreas fault system in southern California and accommodates about ten percent of the motion between the Pacific and North American plates (WGCEP, 1995). The fault extends northwesterly from the US -Mexico border to north of the of the Santa Ana Mountains and is divided, from south to north, into the Coyote Mountain, Julian, Temecula, and Glen Ivy segments. North of the Santa Ana Mountains the fault splits into the Whittier and Chino faults. The fault has historically produced a --M 6 earthquake on the Glen Ivy Segment (Toppozada and Parke, • 1982; Rockwell et al., 1986) and a M>6.9 event on the Laguna Salada fault, the southern extension of the Elsinore fault in Mexico (Rockwell, 1989; Mueller and Rockwell, 1995) indicating the fault is active and capable of producing destructive earthquakes. Three-dimensional paleoseismic studies across the Wildomar strand of the Temecula segment yielded minimum late Holocene slip rates of about 4.2 mm/yr (Bergmann et al., 1993). This is roughly consistent with slip rates of about 5 mm/yr derived from dated offset alluvial fan deposits on the Glen Ivy segment to the north (Millman and Rockwell, 1986), and the Julian segment to the south (Vaughan and Rockwell, 1986). Although no individual earthquakes have been directly dated on the Wildomar fault, paleoseismic studies on the Murrieta Creek fault, an oblique -slip fault secondary to the Temecula segment, suggest an average recurrence interval of 300 to 700 years for the Elsinore fault in the Murrieta area. This is broadly consistent with a calculated average recurrence of about 240 years based on segment length and empirical relations of Wells and Coppersmith (1994). Using this recurrence interval, and a minimum 175 years of historical quiescence on the fault, the Working Group on California Earthquake Probabilities (WGCEP, 1995) suggests that the Temecula segment has a 16 percent chance of rupturing by the year 2024. Recent paleoseismic studies on the southeastern end of the Temecula segment, near Agua Tibia Mountain, however, suggest a longer average recurrence interval of 550 to 600 years for the segment, making the likelihood of an earthquake on the Temecula segment less than five percent in the next 50 years (Vaughan et al., 1999). The deterministic analysis for the Newport Beach City Hall area estimates peak ground • accelerations of about 0.19g for a magnitude 7.6 earthquake on the Chino segment, and Earth Consultants International Seismic Hazards Page 2-29 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • about 0.15g, based on a magnitude 6.8 earthquake on the Glen Ivy segment of the Elsinore fault. 2.5.8 Sierra Madre Fault The Sierra Madre fault zone is a north -dipping reverse fault zone approximately 47 miles (75 km) long that extends along the southern flank of the San Gabriel Mountains from San Fernando to San Antonio Canyon, where it continues southeastward as the Cucamonga fault. The Sierra Madre fault has been divided into five segments, each with a different rate of activity. The northwestern -most segment of the Sierra Madre fault (the San Fernando segment) ruptured in 1971, causing the M,, 6.7 San Fernando (or Sylmar) earthquake. As a result of this earthquake, the Sierra Madre fault has been known to be active. In the 1980s, Crook and others (1987) studied the Transverse Ranges using general geologic and geomorphic mapping, coupled with a few trenching locations. Based on this work, they suggested that segments of the Sierra Madre fault east of the San Fernando segment have not generated major earthquakes in several thousands of years, and possibly as long as 11,000 years. By California's definitions of active faulting, most of the Sierra Madre fault would therefore be classified as not active. Then, in the mid- 1990s, Rubin et al. (1998) trenched a section of the Sierra Madre fault in Altadena and determined that this segment had ruptured at least twice in the last 15,000 years, causing magnitude 7.2 to 7.6 earthquakes. This suggests that the Los Angeles area is susceptible to infrequent, but large near -field earthquakes on the Sierra Madre fault. Rubin et al.'s (1998) trenching data show that during the last . earthquake, the ground was displaced along the fault as much as 13 feet (4 meters) at the surface, and that total displacement in the last two events adds up to more than 34 feet (10.5 meters)! Although the fault apparently slips at a slow rate of between 0.5 and 1 mm/yr (Walls et al., 1998), over time, it can accumulate a significant amount of strain. The paleoseismic data obtained at the Altadena site were insufficient to estimate the recurrence interval and the age of the last surface -rupturing event on this segment of the fault. However, Tucker and Dolan (2001) trenched the east Sierra Madre fault at Horsethief Canyon and obtained data consistent with Rubin et al.'s (1998) findings. At Horsethief Canyon, the Sierra Madre fault last ruptured about 8,000 to 9,000 years ago. A recurrence interval of about 8,000 years was calculated using a slip rate of 0.6 mm/yr and a slip per event of 15 feet (5 meters). Therefore, if the last event occurred more than 8,000 years ago, it is possible that these segments of the Sierra Madre fault are near the end of their cycle, and are likely to generate an earthquake in the not too distant future. The deterministic analysis for the Newport Beach City Hall area estimates peak ground accelerations of about 0.15g, based on a magnitude 7.0 earthquake on the central segment of the Sierra Madre fault. A larger earthquake on this fault, of magnitude between 7.2 and 7.6, could generate significantly stronger peak ground accelerations. 2.6 Potential Sources of Fault Rupture . 2.6.1 Primary Fault Rupture Primary fault rupture refers to fissuring and offset of the ground surface along a rupturing Earth Consultants International Seismic Hazards Page 2-30 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • fault during an earthquake. Primary ground rupture typically results in a relatively small percentage of the total damage in an earthquake, but being too close to a rupturing fault can cause severe damage to structures. As discussed previously, development constraints within active fault zones were implemented in 1972 with passage of the California Alquist- Priolo Earthquake Fault Zoning Act. The Alquist-Priolo Act prohibits the construction of new habitable structures astride an active fault and requires special geologic studies to locate and evaluate whether a fault has ruptured the ground surface in the last about 11,000 years. If an active fault is encountered, structural setbacks from the fault are defined. The Newport -Inglewood fault is the only fault with the potential to generate primary surface rupture in the city of Newport Beach. The North Branch of the Newport - Inglewood fault as mapped by Morton (1999) comes on shore (from the south) near the intersection of Balboa Boulevard and 151h Street, then crosses the Newport Channel and continues through the Pacific Coast Highway -Balboa Boulevard intersection (Plate 2-2). The fault trace then continues through the foot of the bluffs, across the old Newport - Banning oil field, and into the city of Huntington Beach. The South Branch comes on shore in Huntington Beach, just up the coast from the Santa Ana River (Plate 2-2). However, in Newport Beach, the North Branch is not considered sufficiently active and well defined by the CGS, and as a result, the fault in the Newport Beach area has not been zoned under the guidelines of the Alquist-Priolo Earthquake Fault Zoning Act (Plate 2-2). Farther north, the fault is better defined, which is why Alquist-Priolo Earthquake Fault Zones have been defined for the North Branch in Huntington Beach. • The lowland area of West Newport that is thought to be underlain by the North Branch of the fault (see Plate 2-2) was developed extensively prior to recognition of the Newport - Inglewood fault as a surface rupture hazard. Therefore, there are no studies of the fault zone in the West Newport and Balboa Peninsula areas. Furthermore, the sediments in these areas are too young, and ground water is too close to the ground surface for trenching to be used as a successful fault study method. Subsurface studies using other techniques such as cone penetrometer testing (CPTs, see Grant et al., 1997) or geophysics could be used along the beach, but this has not been tried in this area. On the elevated terrace of Newport Mesa, however, several fault studies have been conducted looking for the active strands of the fault. The first studies to identify faults at or near the surface in the Newport Banning area were reportedly conducted jointly by Woodward -Clyde Consultants and the West Newport Oil Company in 1981 and 1985. Additional studies have been conducted by The Earth Technology Corporation (1986) and by Earth Consultants International (1997). The results of the 1981 study were published (Guptill and Heath, 1981) because one of the exposures reviewed — located approximately 600 feet northwest of the intersection of Pacific Coast Highway and Superior Avenue — suggested that the 1933 earthquake had actually ruptured the ground surface. This finding was not confirmed by The Earth Technology Corporation 1986 study who reported that the fault does not offset a well -developed soil profile estimated to be about 100,000 years old (Bryant, 1988). The 1985 study (summarized by The Earth Technology Corporation, 1986) exposed a • broad area of faulting in the western central and southeastern portion of the mesa. The faults in the western portion of the mesa are roughly coincident with the mapped trace of Earth Consultants International Seismic Hazards Page 2-31 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • the North Branch of the fault (see Plate 2-2). However, the 1985 study did not resolve the length, width or age of the faults. Then in 1986, The Earth Technology Corporation found that the faults encountered were not active under the criteria of the Alquist-Priolo Act. With one exception in the southeastern portion of the mesa discussed further below, this finding was confirmed locally by Earth Consultants International in 1997. These studies combined, however, suggest that the North Branch of the Newport -Inglewood fault, as mapped, is not active, at least not in this area of Newport Beach. Converse Consultants (1994) found a small fault, the West Mesa fault, near the western terminus of West 16" Street, while conducting a geologic study and grading for a filtration water plant (see Plate 2-2). The West Mesa fault trends between 5 and 30 degrees west of north, and is interpreted to have moved in the last 11,000 years, making it active. Earth Consultants International (1997) then trenched south of the Converse (1994) exposure in an attempt to find the southern continuation of this fault, but the fault was not found, suggesting that the fault is not laterally extensive. However, Earth Consultants International 0 997) did find another small active fault about 600 feet to the south of the Converse study that strikes 50 degrees west of north, roughly parallel to the regional trend of the Newport - Inglewood fault. In the exposure, the fault had 12 to 18 inches of vertical separation, extended upward into the E and Bt soil horizons, and was therefore interpreted to have ruptured at least once in the last 11,000 years, probably co -seismically with movement on the main Newport -Inglewood fault. Further, in reviewing previous work in the Newport Mesa area, Earth Consultants • International (1997) concluded that a narrow fault zone mapped by The Earth Technology Corporation (1986) was not conclusively shown to be inactive. This fault zone trends 5 to 12 degrees west of north, similar to the orientation of the fault exposed by Converse (1994). All of these faults in the eastern portion of the mesa are not considered seismogenic (earthquake -producing) because of their small separations, narrow width, and non -ideal orientations. The separation seen on these faults probably resulted from co - seismic slip during an earthquake on a strand of the Newport -Inglewood fault farther to the south. Nevertheless, several inches of ground offset could cause severe damage to overlying structures. Consequently, although the hazard from primary surface rupture on these small faults is possibly low, building setbacks from these faults are appropriate. • Finally, two paleoseismic investigations, one near Bolsa Chica (Grant et al., 1997) and the other on the west bank of the Santa Ana River (Law/Crandall, Inc., 1994; Shlemon et al., 1995) found evidence for five surface rupturing earthquakes in the last-11,000 years on the North Branch of the Newport -Inglewood fault. The Law/Crandall (1994) study identified several fault traces south of the mapped trace of the North Branch of the Newport -Inglewood that appear to have moved in the Holocene. In Plate 2-2, these fault traces are projected as straight lines from the west bank of the Santa Ana River southward into the Newport Beach area. This shows that the active faults appear to be located south of the North Branch, with active faulting spread over a broad area that most likely spans the area between the North and South branches. However, the location of these faults should be considered approximate at best, until further studies in this area are conducted. Earth Consultants International Seismic Hazards Page 2-32 2003 • • .` too , r , `.� (Law/Citrurdal, 1' 6 , 1 , v , 1 Y., t \ \` f 1 /r , \ 1 1 ,, P • v` _I 1� West Mesa Fault A (Converse, 1994) 1 1, —(Eiirnh Coxltanis Int, 1997) , e � J _ (The Earth TechnologyfCorp/'1986- Earth Consultants Irit., 1997) NOTES This map Is Intended for general land use planning only. Information on this map Is not sufficient to serve as a substitute for detailed geologic investigations of individual sites, nor does II satisfy the evaiustion requirements set forth In geologic hazard regulations. Earth Consultants International (ECp makes no representations or vvammiles regarding the accuracy of the data from which these maps vvere derived. ECI shall not be liable under any circumstances for any direct, indirect, special, Incidental, or consequential damages with respect to any claim by any user or third party on account of, or arising from, the use of this map. ,, p' .n % i �,X l'([]`t,` ,� ,♦ C' �• '1 , `` , ♦ , 4 Fault Map Newport Beach, California EXPLANATION Fault: solid where location known, long dashed where approximate, dotted where inferred. �\ Faults that are not active. Major fault traces as mapped by Morton, 1999. I\ Presumed active, except where shown otherwise based on geological studies. Southward projection of active fault traces based r on a subsurface study on the west bank of the Santa Ana River. ,I Secondary fault traces that have been shown to have moved at least once during the Holocene -Fault Hazard Management Zone for real-estate disclosure purposes (refer to text). Newport Beach City Boundary Sphere of Influence Scale: 1:60,000 11.5 1) 0.5 1 1.5 Miles 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from Sure!MAPS RASTER Source: Earth Technology Corp., 1986; Converse,1994; Law/Crandall, 1994, Earth Consultants Int., 1997; Morton, 1999. Earth '�00 ��"POAI Consultants 2 Intemational Project Number: 2112 -<a> Date: July, 2003 Plate 2-2 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The activity and location of the North Branch, and the faults south of the North Branch farther southeast, along West Newport and the Balboa Peninsula are unknown. Ideally, geologic studies similar in scope to those required by the CGS in Alquist-Priolo Earthquake Fault Zones should be conducted if new development or redevelopment is proposed in these areas. In reality, such investigations are not likely to be successful due to the small lot sizes and very high building density in these portions of the City, combined with the underlying, geologically young beach and sand dune deposits and shallow ground water. Trenching in these areas could also negatively impact adjacent properties. It is herein recommended that a "fault disclosure zone" be placed along the area between the mapped alignments of the North and South branches of the Newport -Inglewood fault, in the area where recent studies suggest that the recently active traces of the fault are located. The purpose of this fault disclosure zone is to make the public aware of the potential hazard (Plate 2-2). If detailed geological investigations are conducted, the location and activity status (some of the splays may be proven to have not moved within the last 11,000 years) of the faults shown on Plate 2-2 may be refined or modified. The map should be amended as new data become available and are validated. Although the San Joaquin Hills fault may generate very strong earthquakes, damage from primary surface rupture is low because this fault is "blind." By definition, a blind thrust is a reverse fault that does not break the surface during an earthquake. For example, the 1994 Northridge earthquake ruptured on the blind Oakridge fault and was the most costly earthquake in U.S. history, buy it did not break the surface. However, ground deformation resulting from uplifting of the landmass during a San Joaquin Hills fault quake could • damage portions of Newport Beach. Several other faults, such as the Pelican Hill fault, and the Shady Canyon fault (north of the City) have been mapped in the San Joaquin Hills (see Plate 2-2). These faults appear to be confined to the older bedrock units, with no impact on the younger, Holocene terrace and alluvial deposits, and are therefore not considered active. Special geological studies for these faults are not considered warranted. MITIGATION OF PRIMARY FAULT RUPTURE r Geologic studies on the Newport -Inglewood fault suggest that slip per event on this fault typically exceeds 3 feet (1 m). Most engineered structures are not designed to withstand this amount of movement, so buildings that straddle a fault will most certainly be damaged beyond repair if and when the fault breaks the surface. Since it is impractical to reduce the damage potential to acceptable levels by engineering design, the most appropriate mitigation measure is to simply avoid placing structures on or near active fault traces. However, because of the complexity of most active fault zones, particularly at the surface where they may become braided, splayed or segmented, locating and evaluating the active traces is often not an easy task. A geologic investigation, which may include fault trenching, must be performed if structures designed for human occupancy are proposed within an Alquist-Priolo Earthquake Fault Zone. The study must evaluate whether or not an active segment of the fault extends across the area of proposed development. Based on the results of these studies, appropriate structural setbacks can be recommended. Specific guidelines for evaluating the hazard of fault rupture are presented in Note 49, published by • the CGS, which is available on the world wide web at: www.consrv.ca.Zov/DMG/dubs/notes/,t9/1 ndex.htm. Earth Consultants International Seismic Hazards Page 2-34 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . A common misperception regarding setbacks is that they are always 50 feet from the active fault trace. In actuality, geologic investigations are required to characterize the ground deformation associated with an active fault. Based on these studies, specific setbacks are recommended. If a fault trace is narrow, with little or no associated ground deformation, a setback distance less than 50 feet may be recommended. Conversely, if the fault zone is wide, with multiple splays, or is poorly defined, a setback distance greater than 50 feet may be warranted. State law allows local jurisdictions to establish minimum setback distances from a hazardous fault, and some communities have taken a prescriptive approach to this issue, establishing specific setbacks from a fault, rather than allowing for different widths depending on the circumstances. For example, the City of West Hollywood requires a 50-foot setback from the Hollywood fault for conventional structures, and 100-foot setback for critical and high -occupancy facilities. 2.6.2 Secondary Fault Rupture and Related Ground Deformation Primary fault rupture is rarely confined to a simple line along the fault trace. As the rupture reaches the brittle surface of the ground, it commonly spreads out into complex fault patterns of secondary faulting and ground deformation. In the 1992 Landers earthquake, the zone of deformation around the main trace ranged up to hundreds of feet wide (Lazarte et al., 1994). Surface displacement and distortion associated with secondary faulting and deformation can be relatively minor or can be large enough to cause significant damage to structures. Secondary fault rupture refers to ground surface displacements along faults other than the • main traces of active regional faults. Unlike the regional faults, these subsidiary faults are not deeply rooted in the Earth's crust and are not capable of producing damaging earthquakes on their own. Movement along these faults generally occurs in response to movement on a nearby regional fault. The zone of secondary faulting can be quite large, even in a moderate -sized earthquake. For instance, in the 1971 San Fernando quake, movement along subsidiary faults occurred as much as 2 km from the main trace (Ziony and Yerkes, 1985). Secondary faulting in thrust fault terrain is very complex, and numerous types of faulting have been reported. These include splays, branches, tear faults, shallow thrust faults, and back -thrusts, as well, as faults that form in the shallow subsurface as a result of folding in sedimentary layers. Identified by Yeats 0 982), fold -related types include flexural slip faults (slippage along bedding planes), and bending -moment faults (tensional or compressional tears in the axis of folding). A striking example of flexural slip along bedding planes occurred during the Northridge earthquake, when numerous bedding plane faults ruptured across the surface of newly graded roads and pads in a subdivision near Santa Clarita. The ruptures were accompanied by uplift and warping of the nearby ground (Treiman, 1995). Deformation of this type could occur in Newport Beach, particularly in the hillside areas, during the next moderate -sized earthquake on the San Joaquin Hills fault. Secondary ground deformation includes fracturing, shattering, warping, tilting, uplift and/or subsidence. Such deformation may be relatively confined along the rupturing fault, or spread over a large region (such as the regional uplift of the Santa Susana Mountains after • the Northridge earthquake). Deformation and secondary faulting can also occur without Earth Consultants International Seismic Hazards Page 2-35 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • primary ground rupture, as in the case of ground deformation above a blind (buried) thrust fault. MITIGATION OF SECONDARY FAULT RUPTURE AND GROUND DEFORMATION Geotechnical investigations for future development and redevelopment should consider this hazard. The methodology for evaluating these features is similar to that used for evaluating primary fault rupture (CGS, previously CDMG Note 49). Lazarte (1994) outlined three approaches to mitigation of fault rupture hazard, which could be applied to secondary deformation as well. The first is avoidance, by the use of structural setback zones. The second is referred to as "geotechnical engineering." This method consists of placing a compacted fill blanket, or a compacted fill blanket reinforced with horizontal layers of geogrid, over the top of the fault trace. This is based on observations that the displacement across a distinct bedrock fault is spread out and dissipated in the overlying fill, thus reducing the severity of the displacement at the surface. The third method is "structural engineering." This refers to strengthening foundation elements to withstand a limited amount of ground deformation. This is based on studies of foundation performance in the Landers earthquake showing that structures overlying major fault ruptures suffered considerable damage but did not collapse. Application of the second and third methods requires a thorough understanding of the geologic environment and thoughtful engineering judgment. This is because quantifying the extent of future displacement is difficult, and there are no proven engineering standards in place to quantify the amount of mitigation needed (for instance how thick a fill blanket is needed). • 2.7 Geologic Hazards Resulting from Seismic Shaking 2.7.1 Liquefaction and Related Ground Failure Liquefaction is a geologic process that causes various types of ground failure. Liquefaction typically occurs in loose, saturated sediments primarily of sandy composition, in the presence of ground accelerations over 0.2g (Borchardt and Kennedy, 1979; Tinsley and Fumal, 1985). When liquefaction occurs, the sediments involved have a total or substantial loss of shear strength, and behave like a liquid or semi -viscous substance. Liquefaction can cause structural distress or failure due to ground settlement, a loss of bearing capacity in the foundation soils, and the buoyant rise of buried structures: The excess hydrostatic pressure generated by ground shaking can result in the formation of sand boils or mud spouts, and/or seepage of water through ground cracks. As indicated above, there are three general conditions that need to be met for liquefaction to occur. The first of these — strong ground shaking of relatively long duration — can be expected to occur in the Newport Beach area as a result of an earthquake on any of several active faults in the region (see Section 2.5 above). The second condition — loose, unconsolidated sediments consisting primarily of silty sand and sand - occurs along the coastline from West Newport to the tip of Balboa Peninsula, as well as in and around Newport Bay. Young alluvial sediments also occur along the larger drainages (e.g., Bonita Canyon) within the City. (see Plates 3-1 and 3-2 in Chapter 3 — Geologic Hazards). The third condition — water -saturated sediments within about 50 feet of the surface — occurs • along the coastline, in and around Newport Bay and Upper Newport Bay, in the lower reaches of major streams in Newport Beach, and in the floodplain of the Santa Ana River. Earth Consultants International Seismic Hazards Page 2-36 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Therefore, these are the areas with the potential to experience future liquefaction -induced ground displacements. The potentially liquefiable areas are shown on Plate 2-3, and are discussed further below. Structures built on the sand dune deposits lining the coast from the mouth of the Santa Ana (� River to the end of Balboa Peninsula are highly susceptible to liquefaction during an Y— earthquake because depth to the water table is less than 15 feet. Likewise, buildings on the estuary deposits within and around Newport Bay are equally at risk from seismically induced liquefaction because of the shallow water table (Plate 2-3). Areas along major stream channels, such as Bonita and Big Canyon, are also vulnerable to liquefaction, especially during wet climatic conditions/seasons. Liquefaction hazard is also mapped along Buck Gully, Los Trancos Canyon, Muddy Canyon, and the beach area from Corona del Mar to the eastern boundary of Newport Beach near Reef Point (Plate 2-3). Although not mapped, shallow groundwater conditions may occur locally in smaller drainages throughout central and eastern Newport Beach. Since the bedrock that forms the San Joaquin Hills weathers to sand -sized particles, some of the canyons may contain sediments susceptible to liquefaction. For example, sediments lining streams flowing southwest off Pelican Hill may be susceptible to liquefaction. The potential for these areas to liquefy should be evaluated on a case -by -case basis. Additionally, areas of artificial fill that have been placed on liquefiable soils may also be at risk. It is likely that residential or commercial development will never occur in many of the . liquefiable areas, such as Upper Newport Bay, the Newport Coast beaches, and the bottoms of stream channels. However, other structures (such as bridges, roadways, major utility lines, and park improvements) that occupy these areas are vulnerable to damage from liquefaction if mitigation measures have not been included in their design. Construction planned for these areas should include liquefaction mitigation measures, weighing the factors of public safety, the impact to the environment, and the risk of economic loss. For instance, a parking lot at the beach may not warrant ground modification measures, especially if the mitigation measures would be destructive to the environment, but a bridge abutment for a busy roadway would. A considerable part of the City's mapped liquefiable areas (West Newport, Balboa Peninsula, the harbor islands and vicinity) are already built upon, mostly with residential and commercial development. City Hall and a portion of the City's active oil field are also built on liquefiable soils. It is likely that a nearby moderate to strong earthquake will cause extensive damage to buildings and infrastructure in these areas. Since retrofitting mitigation measures are generally not feasible, the City should be prepared to respond to damage and disruption in the event of an earthquake. Earth Consultants International Seismic Hazards Page 2-37 2003 • a NOTES This map Is Intended for general land use planning only. Information on this map Is not suPoolent to serve as a substdute for detailed geologic investigations of IndiNdual ekes, nor does It satisfy the evaluation requirements set forth in geologic hazard regulations. Earth Consultants International (ECI) makes no representations or werranties regarding the accuracy of the data from which these maps were derived. ECI shall not be liable under any circumstances for any direct, indirect, special, incidental, or consequential damages with respect to any claim by any user or third party on account of, or arising from, the use of this map. Seismic Hazards Map Newport Beach, California EXPLANATION _Areas where historic occurrence of liquefaction, or local geological, geotechnical and groundwater conditions indicate a potential for permanent ground displacements such that mitigation as defined in Public Resources Code Section 2893c would be required. ® Areas where previous occurrence of landslide movement, or local topographic, geological, geotechnical and groundwater conditions ! Indicate a potential for permanent ground displacements such that mitigation as `` defined in Public Resources Code Section f 2693c would be required. -aig Newport Beach City Boundary j� �n,• Sphere of Influence t�~y� Scale: 1:60,000 0.5 0 0.5 1 1.5 NMes / © I N 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from Sure1MAPS RASTER Source: California Geological Survey, 1997; Revised 2001 •4 (Newport, Tustin and Laguna Beach Quadrangles). A& _ Ealth F'EwPo4T 10 Y, lA'• � r r Project Number: 2112 Date: July, 2003 UN1 �' e•..mw ''` Plate 2-3 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The types of ground failure typically associated with liquefaction are explained below. Lateral Spreading - Lateral displacement of surficial blocks of soil as the result of liquefaction in a subsurface layer is called lateral spreading. Even a very thin liquefied layer can act as a hazardous slip plane if it is continuous over a large enough area. Once liquefaction transforms the subsurface layer into a fluid -like mass, gravity plus inertial forces caused by the earthquake may move the mass downslope towards a cut slope or free face (such as a river channel or a canal). Lateral spreading most commonly occurs on gentle slopes that range between 0.30 and 30, and can displace the ground surface by several meters to tens of meters. Such movement damages pipelines, utilities, bridges, roads, and other structures. During the 1906 San Francisco earthquake, lateral spreads with displacements of only a few feet damaged every major pipeline. Thus, liquefaction compromised San Francisco's ability to fight the fires that caused about 85 percent of the damage (Tinsley et al., 1985). Lateral Spreading damaged major roads, including Pacific Coast Highway, around Newport Beach during the 1933 Long Beach Earthquake (Coffman and Stover, 1993). Flow Failure - The most catastrophic mode of ground failure caused by liquefaction is flow failure. Flow failure usually occurs on slopes greater than 30. Flows are principally liquefied soil or blocks of intact material riding on a liquefied subsurface. Displacements are often in the tens of meters, but in favorable circumstances, soils can be displaced for tens of miles, at velocities of tens of miles per hour. For example, the extensive damage to Seward and Valdez, Alaska, during the 1964 Great Alaskan earthquake was caused by • submarine flow failures (Tinsley et al., 1985). Ground Oscillation - When liquefaction occurs at depth but the slope is too gentle to permit lateral displacement, the soil blocks that are not liquefied may separate from one another and oscillate on the liquefied zone. The resulting ground oscillation may be accompanied by the opening and closing of fissures (cracks) and sand boils, potentially damaging structures and underground utilities (Tinsley et al., 1985). Loss of Bearing Strength - When a soil liquefies, loss of bearing strength may occur beneath a structure, possibly causing the building to settle and tip. If the structure is buoyant, it may float upward. During the 1964 Niigata, Japan earthquake, buried septic tanks rose as much as 3 feet, and structures in the Kwangishicho apartment complex tilted as much as 60° (Tinsley et al., 1985). Ground Lurching - Soft, saturated soils have been observed to move in a wave -like manner in response to intense seismic ground shaking, forming ridges or cracks on the ground surface. At present, the potential for ground lurching to occur at a given site can be predicted only generally. Areas underlain by thick accumulation of colluvium and alluvium appear to be the most susceptible to ground lurching. Under strong ground motion conditions, lurching can be expected in loose, cohesionless soils, or in clay -rich soils with high moisture content. In some cases, the deformation remains after the shaking stops (Barrows et al., 1994). • LIQUEFACTION MITIGATION MEASURES In accordance with the SHMA, all projects within a State -delineated Seismic Hazard Zone Earth Consultants International Seismic Hazards Page 2-39 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • for liquefaction must be evaluated by a Certified Engineering Geologist and/or Registered Civil Engineer (this is typically a civil engineer with training and experience in soil engineering). Most often however, it is appropriate for both the engineer and geologist to be involved in the evaluation, and in the implementation of the mitigation measures. Likewise, project review by the local agency must be performed by geologists and engineers with the same credentials and experience. In order to assist project consultants and reviewers in the implementation of the SHMA, the State has published specific guidelines for evaluating and mitigating liquefaction (California Division of Mines and Geology, 1997). Furthermore, in 1999, a group sponsored by the Southern California Earthquake Center (SCEC, 1999) published recommended procedures for carrying out the CGS guidelines. In general, a liquefaction study is designed to identify the depth, thickness, and lateral extent of any liquefiable layers that would affect the project site. An analysis is then performed to estimate the type and amount of ground deformation that might occur, given the seismic potential of the area. Mitigation measures generally fall in one of two categories: ground improvement or foundation design. Ground improvement includes such measures as removal and recompaction of low -density soils, removal of excess ground water, in -situ ground densification, and other types of ground improvement (such as grouting or surcharging). Special foundations that may be recommended range from deep piles to reinforcement of shallow foundations (such as post -tensioned slabs). Mitigation for lateral spreading may also include modification of the site geometry or inclusion of retaining structures. The type • (or combinations of types) of mitigation depend on the site conditions and on the nature of the proposed project (CDMG, 1997). • It should be remembered that Seismic Hazard Zone Maps may not show all areas that have the potential for liquefaction, nor is information shown on the maps sufficient to serve as a substitute for detailed site investigations. 2.7.2 Seismically Induced Settlement Under certain conditions, strong ground shaking can cause the densification of soils, resulting in local or regional settlement of the ground surface. During strong shaking, soil grains become more tightly packed due to the collapse of voids and pore spaces, resulting in a reduction of the thickness of the soil column. This type of ground failure typically occurs in loose granular, cohesionless soils, and can occur in either wet or dry conditions. Unconsolidated young alluvial deposits are especially susceptible to this hazard. Artificial fills may also experience seismically induced settlement. Damage to structures typically occurs as a result of local differential settlements. Regional settlement can damage pipelines by changing the flow gradient on water and sewer lines, for example. Those portions of the Newport Beach area that may be susceptible to seismically induced settlement are those underlain by late Quaternary unconsolidated sediments (similar to the liquefaction -susceptible areas shown on Plate 2-3). Earth Consultants International Seismic Hazards Page 2-40 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • MITIGATION OF SEISMICALLY INDUCED SETTLEMENT Mitigation measures for seismically induced settlement are similar to those used for liquefaction. Recommendations are provided by the project's geologist and soil engineer, following a detailed geotechnical investigation of the site. Overexcavation and recompaction is the most commonly used method to density soft soils susceptible to settlement. Deeper overexcavation below final grades, especially at cut/fill, fill/natural or alluvium/bedrock contacts may be recommended to provide a more uniform subgrade. Overexcavation should also be performed so that large differences in fill thickness are not present across individual lots. In some cases, specially designed deep foundations, strengthened foundations, and/or fill compaction to a minimum standard that is higher than that required by the UBC may be recommended. 2.7.3 Seismically Induced Slope Failure Strong ground motions can worsen existing unstable slope conditions, particularly if coupled with saturated ground conditions. Seismically induced landslides can overrun structures, people or property, sever utility lines, and block roads, thereby hindering rescue operations after an earthquake. Over 11,000 landslides were mapped shortly after the 1994 Northridge earthquake, all within a 45-mile radius of the epicenter (Harp and Jibson, 1996). Although numerous types of earthquake -induced landslides have been identified, the most widespread type generally consists of shallow failures involving surficial soils and the uppermost weathered bedrock in moderate to steep hillside terrain (these are also called disrupted soil slides). Rock falls and rock slides on very steep slopes are also common. The 1989 Loma Prieta and Northridge earthquakes showed that reactivation of • existing deep-seated landslides also occurs (Spittler et al., 1990; Barrows et al., 1995). Numerous landslides have been mapped in the San Joaquin Hills in eastern Newport Beach (Plates 3-1 and 3-4, Chapter 3). A combination of geologic conditions leads to landslide vulnerability. These include high seismic potential; rapid uplift and erosion resulting in steep slopes and deeply incised canyons; highly fractured and folded rock; and rock with inherently weak components, such as silt or clay layers. The orientation of the slope with respect to the direction of the seismic waves (which can affect the shaking intensity) can also control the occurrence of landslides. Much of the area in eastern Newport Beach has been identified as vulnerable to (� seismically induced slope failure. Approximately 90 percent of the land from Los Trancos �r— Canyon to State Park boundary is mapped as susceptible to landsliding by the California Geologic Survey (Plate 2-3). The occurrence of numerous Holocene to latest Pleistocene (recent to about 20,000 years ago) landslides indicate that slope failures have been common over a relatively short geologic time period and thus, without mitigation, pose a significant hazard to developments in these areas. Additionally, the sedimentary bedrock that crops out in the San Joaquin Hills is locally highly weathered. In steep areas, strong ground shaking can cause slides or rockfalls in this material. Rupture along the Newport - Inglewood Fault Zone and other faults in southern California could reactivate existing landslides and cause new slope failures throughout the San Joaquin Hills. The least vulnerable areas are those located along the major ridgelines and other isolated areas with • low angle slopes (Plate 2-3). Slope failures can also be expected to occur along stream Earth Consultants International Seismic Hazards Page 2-41 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • banks and coastal bluffs, such as Big Canyon, around San Joaquin Reservoir, Newport and Upper Newport Bays, and Corona del Mar. Ground water conditions at the time of the earthquake play an important role in the development of seismically induced slope failures. For instance, the 1906 San Francisco earthquake occurred in April, after a winter of exceptionally heavy rainfall, and produced many large landslides and mudflows, some of which were responsible for several deaths. The 1987 Loma Prieta earthquake however, occurred in October during the third year of a drought, and slope failures were limited primarily to rock falls and reactivation of older landslides that was manifested as ground cracking in the scarp areas but with very little movement (Griggs et al., 1991). MITIGATION OF SEISMICALLY INDUCED SLOPE FAILURE Existing slopes that are to remain adjacent to or within developments should be evaluated for the geologic conditions mentioned above. In general, slopes steeper than about 15 degrees are most susceptible, however failures can occur on flatter slopes if unsupported weak rock units are exposed in the slope face. For suspect slopes, appropriate geotechnical investigation and slope stability analyses should be performed for both static and dynamic (earthquake) conditions. For deeper slides, mitigation typically includes such measures as buttressing slopes or regrading the slope to a different configuration. Protection from rockfalls or surficial slides can often be achieved by protective devices such as barriers, rock fences, retaining structures, catchment areas, or a combination of the above. The runout area of the slide at the base of the slope, and the potential bouncing of • rocks must also be considered. If it is not feasible to mitigate the unstable slope conditions, building setbacks should be imposed. In accordance with the SHMA, all development projects within a State -delineated Seismic Hazard Zone for seismically induced landsliding must be evaluated and reviewed by State - licensed engineering geologists and/or civil engineers (for landslide investigation and analysis, this typically requires both). In order to assist in the implementation of the SHMA, the State has published specific guidelines for evaluating and mitigating seismically induced landslides (CDMG, 1997). More recently, the Southern California Earthquake Center (SCEC, 2002) sponsored the publication of the "Recommended Procedures for Implementation of DMG Special Publication 117." These procedures are expected to be adopted by the Los Angeles and Riverside Counties and other cities and counties in California in the next year or so, pending some slight revisions and further discussions among the geotechnical community. 2.7.4 Deformation of Sidehill Fills Sidehill fills are artificial fill wedges typically constructed on natural slopes to create roadways or level building pads. Deformation of sidehill fills was noted in earlier earthquakes, but this phenomenon was particularly widespread during the 1994 Northridge earthquake. Older, poorly engineered road fills were most commonly affected, but in localized areas, building pads of all ages experienced deformation. The deformation was usually manifested as ground cracks at the cut/fill contacts, differential settlement in the fill wedge, and bulging of the slope face. The amount of displacement on the pads was . generally about three inches or less, but this resulted in minor to severe property damage Consultants International Seismic Hazards Page 2-42 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA (Stewart et al., 1995). This phenomenon was most common in relatively thin fills (about • 27 feet or less) placed near the tops or noses of narrow ridges (Barrows et al., 1995). MITIGATION OF SIDEHILL FILL DEFORMATION Hillside grading designs should be evaluated during site -specific geotechnical investigations to determine if there is a potential for this hazard'. There are currently no proven engineering standards for mitigating sidehill fill deformation, consequently current published research on this topic should be reviewed by project consultants at the time of their investigation. It is thought that the effects of this hazard on structures may be reduced by the use of post -tensioned foundations, deeper overexcavation below finish grades, deeper overexcavation on cut/fill transitions, and/or higher fill compaction criteria. 2.7.5 Ridgetop Fissuring and Shattering Linear, fault -like fissures occurred on ridge crests in a relatively concentrated area of rugged terrain in the Santa Cruz Mountains during the Loma Prieta earthquake. Shattering of the surface soils on the crests of steep, narrow ridgelines occurred locally in the 1971 San Fernando earthquake, but was widespread in the 1994 Northridge earthquake. Ridgetop shattering (which leaves the surface looking as if it was plowed) by the Northridge earthquake was observed as far as 22 miles away from the epicenter. In the Sherman Oaks area, severe damage occurred locally to structures located at the tops of relatively high (greater than 100 feet), narrow (typically less than 300 feet wide) ridges flanked by slopes steeper than about 2.5:1 (horizontal:vertical). It is generally accepted that ridgetop fissuring and shattering is a result of intense amplification or focusing of seismic energy due to local topographic effects (Barrows et al., 1995). • Ridgetop shattering can be expected to occur in the topographically steep portions of the San Joaquin Hills. These areas are rapidly being developed so the hazard associated with ridgetop shattering is increasing. In addition, above ground storage tanks, reservoirs and utility towers are often located on top of ridges, and during strong ground shaking, these can fail or topple over, with the potential to cause widespread damage to development downslope (storage tanks and reservoirs), or disruptions to the lifeline systems (utility towers). MITIGATION OF RIDGETOP FISSURING AND SHATTERING Projects located in steep hillside areas should be evaluated for this hazard by a Certified Engineering Geologist. Although it is difficult to predict exactly where this hazard may occur, avoidance of development along the tops of steep, narrow ridgelines is probably the best mitigation measure. For large developments, recontouring of the topography to reduce the conditions conducive to ridgetop amplification, along with overexcavation below finish grades to remove and recompact weak, fractured bedrock might reduce this hazard to an acceptable level. 2.7.6 Seiches Reservoirs, lakes, ponds, swimming pools and other enclosed bodies of water are subject to potentially damaging oscillations (sloshing) called Seiches. This hazard is dependent upon specific earthquake parameters (e.g. frequency of the seismic waves, distance and direction from the epicenter), as well as site -specific design of the enclosed bodies of • water, and is thus difficult to predict. Areas of the City that may be vulnerable to this Earth Consultants International Seismic Hazards Page 2-43 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA hazard are primarily improvements located next to waterways, such as Newport Harbor, • and the southern part of Upper Newport Bay, however, as discussed previously in Chapter 1, the risk of seiching in the area is considered low. The San Joaquin and Big Canyon Reservoirs would also be subject to seiches. This is discussed further in Section 4.2 of Chapter 4 —Flooding Hazards). Minor seiching in pools can also occur. MITIGATION OF SEICHES The degree of damage'to small bodies of water, such as to swimming pools, would likely be minor. However, property owners downslope from pools that could seiche during an earthquake should be aware of the potential hazard to their property should a pool lose substantial amounts of water during an earthquake. Site -specific design elements, such as baffles, to reduce the potential for seiches are warranted in tanks and in open reservoirs or ponds where overflow or failure of the structure may cause damage to nearby properties. Damage to water tanks in recent earthquakes, such as the 1992 Landers -Big Bear sequence and the 1994 Northridge, resulted from seiching. As a result, the American Water Works Association (AWWA) Standards for Design of Steel Water Tanks (D-100) provide new criteria for seismic design (Lund, 1994). Damage to watercraft and boat docking facilities, and potentially to waterfront homes and businesses, is likely in the event of seiches in Newport Harbor. 2.8 Vulnerability of Structures to Earthquake Hazards This section assesses the general earthquake vulnerability of structures and facilities common in the Newport Beach area. This analysis is based on past earthquake • performance of similar types of buildings in the U.S. The effects of design earthquakes on particular structures within the City are beyond the scope of this study. However, utilizing a recent standardized methodology developed for the Federal Emergency Management Agency (FEMA), general estimates of losses are provided in Section 2.9 of this report. Although it is not possible to prevent earthquakes from occurring, their destructive effects can be minimized. Comprehensive hazard mitigation programs that include the identification and mapping of hazards, prudent planning and enforcement of building codes, and expedient retrofitting and rehabilitation of weak structures can significantly reduce the scope of an earthquake disaster. With these goals in mind, the State Legislature passed Senate Bill 547, addressing the identification and seismic upgrade of Unreinforced Masonry (URM) buildings. In addition, the law encourages identification and mitigation of seismic hazards associated with other types of potentially hazardous buildings, including pre-1971 concrete tilt -ups, soft -stories, mobile homes, and pre-1940 homes. 2.8.1 Potentially Hazardous Buildings and Structures Most of the loss of life and injuries due to an earthquake are related to the collapse of hazardous buildings and structures. FEMA (1985) defines a hazardous building as "any inadequately earthquake resistant building, located in a seismically active area, that presents a potential for life loss or serious injury when a damaging earthquake occurs." Building codes have generally been made more stringent following damaging earthquakes. • Earth Consultants International Seismic Hazards Page 2-44 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Building damage is commonly classified as either structural or non-structural. Structural • damage impairs the building's support. This includes any vertical and lateral force - resisting systems, such as frames, walls, and columns. Non-structural damage does not affect the integrity of the structural support system, but includes such things as broken windows, collapsed or rotated chimneys, unbraced parapets that fall into the street, and fallen ceilings. During an earthquake, buildings get thrown from side to side and up and down. Given the same acceleration, heavier buildings are subjected to higher forces than lightweight buildings. Damage occurs when structural members are overloaded, or when differential movements between different parts of the structure strain the structural components. Larger earthquakes and longer shaking duration tend to damage structures more. The level of damage can be predicted only in general terms, since no two buildings undergo the exact same motions, even in the same earthquake. Past earthquakes have shown us, however, that some types of buildings are far more likely to fail than others. Unreinforced Masonry Buildings — Unreinforced masonry buildings (URMs) are prone to failure due to inadequate anchorage of the masonry walls to the roof and floor diaphragms, lack of steel reinforcing, the limited strength and ductility of the building materials, and sometimes, poor construction workmanship. Furthermore, as these buildings age, the bricks and mortar tend to deteriorate, making the buildings even weaker. In response to the 1986 URM Law, the City of Newport Beach inventoried their URMs. In(� the year 2000, the City reported to the Seismic Safety Commission that 127 URMs had V� been identified. Of these, only 3 buildings were considered of historical significance. By • 2000, all 127 building owners had been notified about the hazards of URM construction, and 125 of the URMs were in compliance with the provisions of the URM Law. One building had been demolished and one more was unoccupied and slated for demolition as of 2000. E Soft -Story Buildings - Of particular concern are soft -story buildings (buildings with a story, generally the first floor, lacking adequate strength or toughness due to too few shear walls). Apartments above glass -fronted stores, and buildings perched atop parking garages are common examples of soft -story buildings. Collapse of a soft story and "pancaking" of the remaining stories killed 16 people at the Northridge Meadows apartments during the 1994 Northridge earthquake (EERI, 1994). There are many other cases of soft -story collapses in past earthquakes. To date, the City of Newport Beach has reportedly not conducted a survey of their soft -story construction (Mr. Faisal Jurdi, Newport Beach Building Department, personal communication). Wood -Frame Structures - Structural damage to wood -frame structures often results from an inadequate connection between the superstructure and the foundation. These buildings may slide off their foundations, with consequent damage to plumbing and electrical connections. Unreinforced masonry chimneys may also collapse. These types of damage are generally not life threatening, although they may be costly to repair. Wood frame buildings with stud walls generally perform well in an earthquake, unless they have no foundation or have a weak foundation constructed of Unreinforced masonry or poorly reinforced concrete. In these cases, damage is generally limited to cracking of the stucco, Earth Consultants International Seismic Hazards Page 2-45 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA which dissipates much of the earthquake's induced energy. The collapse of wood frame • structures, if it happens, generally does not generate heavy debris, but rather, the wood and plaster debris can be cut or broken into smaller pieces by hand-held equipment and removed by hand in order to reach victims (FEMA, 1985). • • Pre -Cast Concrete Structures - Partial or total collapse of buildings where the floors, walls and roofs fail as large intact units, such as large pre -cast concrete panels, cause the greatest loss of life and difficulty in victim rescue and extrication (FEMA, 1985). These types of buildings are common not only in southern California, but abroad. Casualties as a result of collapse of these structures in past earthquakes, including Mexico (1985), Armenia (1988), Nicaragua (1972), El Salvador (1986 and 2001), the Philippines (1990) and Turkey (1999) add to hundreds of thousands. In southern California, many of the parking structures that failed during the Northridge earthquake, such as the Cal -State Northridge and City of Glendale Civic Center parking structures, consisted of pre -cast concrete components (EERI, 1994). Collapse of this type of structure generates heavy debris, and removal of this debris requires the use of heavy mechanical equipment. Consequently, the location and extrication of victims trapped under the rubble is generally a slow and dangerous process. Extrication of trapped victims within the first 24 hours after the earthquake becomes critical for survival. In most instances, however, post -earthquake planning fails to quickly procure equipment needed to move heavy debris. The establishment of Heavy Urban Search and Rescue teams, as recommended by FEMA (1985), has improved victim extrication and survivability. Buildings that are more likely to fail and generate heavy debris need to be identified, so that appropriate mitigation and planning procedures are defined prior to an earthquake. Tilt -up Buildings - Tilt -up buildings have concrete wall panels, often cast on the ground, or fabricated off -site and trucked in, that are tilted upward into their final position. Connections and anchors have pulled out of walls during earthquakes, causing the floors or roofs to collapse. A high rate of failure was observed for this type of construction in the 1971 San Fernando and 1987 Whittier Narrows earthquakes. Tilt -up buildings can also generate heavy debris. Reinforced Concrete Frame Buildings - Reinforced concrete frame buildings, with or without reinforced infill walls, display low ductility. Earthquakes may cause shear failure (if there are large tie spacings in columns, or insufficient shear strength), column failure (due to inadequate rebar splices, inadequate reinforcing of beam -column joints, or insufficient tie anchorage), hinge deformation (due to lack of continuous beam reinforcement), and non-structural damage (due to the relatively low stiffness of the frame). A common type of failure observed following the Northridge earthquake was confined column collapse (EERI, 1994), where infilling between columns confined the length of the columns that could move laterally in the earthquake. Multi -Story Steel Frame Buildings - Multi -story steel frame buildings generally have concrete floor slabs. However, these buildings are less likely to collapse than concrete structures. Common damage to these types of buildings is generally non-structural, including collapsed exterior curtain wall (cladding), and damage to interior partitions and Earth Consultants International Seismic Hazards 2003 Page 2-46 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA equipment. Overall, modern steel frame buildings have been expected to perform well in • earthquakes, but the 1994 Northridge earthquake broke many welds in these buildings, a previously unanticipated problem. Older, pre-1945 steel frame structures may have unreinforced masonry such as bricks, clay tiles and terra Gotta tiles as cladding or infilling. Cladding in newer buildings may be glass, infill panels or pre -cast panels that may fail and generate a band of debris around the building exterior (with considerable threat to pedestrians in the streets below). Structural damage may occur if the structural members are subject to plastic deformation which can cause permanent displacements. If some walls fail while others remain intact, torsion or soft -story problems may result. Mobile Homes - Mobile homes are prefabricated housing units that are placed on isolated piers, jackstands, or masonry block foundations (usually without any positive anchorage). Floors and roofs of mobile homes are usually plywood, and outside surfaces are covered with sheet metal. Mobile homes typically do not perform well in earthquakes. Severe damage occurs when they fall off their supports, severing utility lines and piercing the floor with jackstands. Combination Types - Buildings are often a combination of steel, concrete, reinforced masonry and wood, with different structural systems on different floors or different sections of the building. Combination types that are potentially hazardous include: concrete frame buildings without special reinforcing, precast concrete and precast -composite buildings, steel frame or concrete frame buildings with unreinforced masonry walls, reinforced • concrete wall buildings with no special detailing or reinforcement, large capacity buildings with long -span roof structures (such as theaters and auditoriums), large un-engineered wood -frame buildings, buildings with inadequately anchored exterior cladding and glazing, and buildings with poorly anchored parapets and appendages (FEMA, 1985). Additional types of potentially hazardous buildings may be recognized after future earthquakes. In addition to building types, there are other factors associated with the design and construction of the buildings that also have an impact on the structures' vulnerability to strong ground shaking. Some of these conditions are discussed below: Building Shape - A building's vertical and/or horizontal shape can also be important. Simple, symmetric buildings generally perform better than non -symmetric buildings. During an earthquake, non -symmetric buildings tend to twist as well as shake. Wings on a building tend to act independently during an earthquake, resulting in differential movements and cracking. The geometry of the lateral load -resisting systems also matters. For example, buildings with one or two walls made mostly of glass, while the remaining walls are made of concrete or brick, are at risk. Asymmetry in the placement of bracing systems that provide a building with earthquake resistance can result in twisting or differential motions. Poundine - Site -related seismic hazards may include the potential for neighboring buildings to "pound", or for one building to collapse onto a neighbor. Pounding occurs . when there is little clearance between adjacent buildings, and the buildings "pound" Earth Consultants International Seismic Hazards Page 2-47 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA against each other as they deflect during an earthquake. The effects of pounding can be • especially damaging if the floors of the buildings are at different elevations, so that, for example, the floor of one building hits a supporting column of the other. Damage to a supporting column can result in partial or total building collapse. 2.8.2 Essential Facilities Essential facilities are those parts of a community's infrastructure that must remain operational after an earthquake. Buildings that house essential services include schools, hospitals, fire and police stations, emergency operation centers, and communication centers. Plate 2-4 shows the locations of the City's fire stations, police stations, schools, and other essential facilities. A vulnerability assessment for these facilities involves comparing their locations to hazardous areas identified in the City, including active and potentially active faults (Plate 2-2), liquefaction -susceptible areas (Plate 2-3), unstable slope areas (Plates 3-1 and 3-4), potential flood areas due to either storm events or coastal processes (Plates 1-3 through 1-5 and 4-2), dam failure inundation areas (Plate 4-3), fire hazard zones (Plates 5-2 and 5-3), and sites that generate hazardous materials (Plate 6-1). High -risk facilities, if severely damaged, may result in a disaster far beyond the facilities themselves. Examples include power plants, dams and flood control structures, and industrial plants that use or store explosives, toxic materials or petroleum products. High -occupancy facilities have the potential of resulting in a large number of casualties or crowd -control problems. This category includes high-rise buildings, large assembly facilities, and large multifamily residential complexes. • Dependent -care facilities, such as preschools and schools, rehabilitation centers, prisons, group care homes, and nursing homes, house populations with special evacuation considerations. • Economic facilities, such as banks, archiving and vital record -keeping facilities, airports, and large industrial or commercial centers, are those facilities that should remain operational to avoid severe economic impacts. It is crucial that essential facilities have no structural weaknesses that can lead to collapse. For example, the Federal Emergency Management Agency (FEMA, 1985) has suggested the* following seismic performance goals for health care facilities: The damage to the facilities should be limited to what might be reasonably expected after a destructive earthquake and should be repairable and not be life -threatening. Patients, visitors, and medical, nursing, technical and support staff within and immediately outside the facility should be protected during an earthquake. Emergency utility systems in the facility should remain operational after an earthquake. Occupants should be able to evacuate the facility safely after an earthquake. Rescue and emergency workers should be able to enter the facility immediately after an earthquake and should encounter only minimum interference and danger. The facility should be available for its planned disaster response role after an earthquake. Earth Consultants International Seismic Hazards Page 2-48 2003 • • I� U I 1 /Fit .. .., --� © •� Civic Center � aw c-. Harbor Master and Coast Guard Station NOTES This map is intended for general land use planning only. Information on This map is not sufficient to servo as a substitute for detailed geologic investigations of individual sites, nor does 1 satlsfythe evaluation requirements set forth In geologic hazard regulations. Earth Consultants International (ECI) makes no representations or warranties regarding the accuracy of the data from which these maps were derived. ECI shall not be liable under any circumstances for any direct, indirect, special, incidental, or consequenlial damages with respect to any claim by any user or third party on account of, or arising from, the use of this map. 1 s r' j r,1 l r' Essential Services Buildings Newport Beach, California EXPLANATION Public Schools * Police Station ^'> Fire Station City Hall p Hospital Harbor Master and Coast Guard Stations Civic Center Newport Beach City Boundary Sphere of Influence Scale: 1:60,000 0.5 0 0.5 1 1.5 Miles 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from Sure!MAPS RASTER Source: City of Newport Beach _�— Consultants t Internatanal Project Number: 2112 Date: July, 2003 Plate 2-4 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 2.8.3 Lifelines Lifelines are those services that are critical to the health, safety and functioning of the community. They are particularly essential for emergency response and recovery after an earthquake. Furthermore, certain critical facilities designed to remain functional during and immediately after an earthquake may be able to provide only limited services if the lifelines they depend on are disrupted. Lifeline systems include water, sewage, electrical power, communication, transportation (highways, bridges, railroads, and airports), natural gas, and liquid fuel systems. The improved performance of lifelines in the 1994 Northridge earthquake, relative to the 1971 San Fernando earthquake, shows that the seismic codes upgraded and implemented after 1971 have been effective. Nevertheless, the impact of the Northridge quake on lifeline systems was widespread and illustrates the continued need to study earthquake impacts, to upgrade substandard elements in the systems, to provide redundancy in systems, to improve emergency response plans, and to provide adequate planning, budgeting and financing for seismic safety. Water supply facilities, such as dams, reservoirs, pumping stations, water treatment plants, and distribution lines are especially critical after an earthquake, not only for drinking water, but to fight fires. Failure of dams and reservoirs during an earthquake is discussed further in Chapter 4. Some of the observations and lessons learned from the Northridge earthquake are summarized below (from Savage, 1995; Lund, 1996). • Several electrical transmission towers were damaged or totally collapsed. Collapse was generally due to foundation distress in towers that were located near ridge tops where amplification of ground motion may have occurred. One collapse was the result of a seismically induced slope failure at the base of the tower. Damage to above ground water tanks typically occurred where piping and joints were rigidly connected to the tank, due to differential movement between the tank and the piping. Older steel tanks not seismically designed under current standards buckled at the bottom (called "elephant's foot"), in the shell, and on the roof. Modern steel and concrete tanks generally performed well. The most vulnerable components of pipeline distribution systems were older threaded joints, cast iron valves, cast iron pipes with rigid joints, and older steel pipes weakened by corrosion. In the case of broken water lines, the loss of fire suppression water forced fire departments to utilize water from swimming pools and tanker trucks. Significant damage occurred in water treatment plants due to sloshing in large water basins. A number of facilities did not have an emergency power supply or did not have enough power supply capacity to provide their essential services. Lifelines within critical structures, such as hospitals and fire stations, may be vulnerable. For instance, rooftop mechanical and electrical equipment is not generally designed for seismic forces. During the Northridge quake, rooftop equipment failed causing malfunctions in other systems. • A 70-year old crude oil pipeline leaked from a cracked weld, spreading oil for 12 miles down the Santa Clara River. Earth Consultants International Seismic Hazards Page 2-50 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The above list is by no means a complete summary of the earthquake damage, but it does highlight some of the issues pertinent to the Newport Beach area. All lifeline providers should make an evaluation of the seismic vulnerability within their systems a priority. The evaluation should include a plan to fund and schedule the needed seismic mitigation. 2.9 HAZUS Earthquake Scenario Loss Estimations for the City of Newport Beach HAZUS-99Tm is a standardized methodology for earthquake loss estimation based on a geographic information system (GIS). A project of the National Institute of Building Sciences, funded by the Federal Emergency Management Agency (FEMA), it is a powerful advance in mitigation strategies. The HAZUS project developed guidelines and procedures to make standardized earthquake loss estimates at a regional scale. With standardization, estimates can be compared from region to region. HAZUS is designed for use by state, regional and local governments in planning for earthquake loss mitigation, emergency preparedness, response and recovery. HAZUS addresses nearly all aspects of the built environment, and many different types of losses. The methodology has been tested against the experience of several past earthquakes, and against the judgment of experts. Subject to several limitations noted below, HAZUS can produce results that are valid for the intended purposes. Loss estimation is an invaluable tool, but must be used with discretion. Loss estimation analyzes casualties, damage and economic loss in great detail. It produces seemingly precise numbers that can be easily misinterpreted. Loss estimation's results, for example, may cite 4,054 left homeless • by a scenario earthquake. This is best interpreted by its magnitude. That is, an event that leaves 4,000 people homeless is clearly more manageable than an event causing 40,000 homeless people; and an event that leaves 400,000 homeless would overwhelm a community's resources. However, another loss estimation that predicts 7,000 people homeless should probably be considered equivalent to the 4,054 result. Because HAZUS results make use of a great number of parameters and data of varying accuracy and completeness, it is not possible to assign quantitative error bars. Although the numbers should not be taken at face value, they are not rounded or edited because detailed evaluation of individual components of the disaster can help mitigation agencies ensure that they have considered all the important options. The more community -specific the data that are input to HAZUS, the more reliable the loss estimation. HAZUS provides defaults for all required information. These are based on best - available scientific, engineering, census and economic knowledge. The loss estimations in this report have been tailored to Newport Beach by using a map of soil types for the City. HAZUS relies on 1990 Census data, but for the purposes of this study, we replaced the population by a census tract data that came with the software with the 2000 Census data. Other modifications made to the data set before running the analyses include: updated the database of critical facilities, including the number and location of the fire and police stations in the City, revised the number of beds available in the one major hospital in Newport Beach to better represent its current patient capacity, and • upgraded the construction level for most unreinforced masonry buildings in the City to better represent the City's retrofitting efforts of the last decade. Earth Consultants International Seismic Hazards Page 2-51 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • As useful as HAZUS seems to be, the loss estimation methodology has some inherent uncertainties. These arise in part from incomplete scientific knowledge concerning earthquakes and their effect upon buildings and facilities, and in part from the approximations and simplifications necessary for comprehensive analyses. Users should be aware of the following specific limitations: HAZUS is driven by statistics, and thus is most accurate when applied to a region, or a class of buildings or facilities. It is least accurate when considering a particular site, building or facility. Losses estimated for lifelines may be less than losses estimated for the general building stock. Losses from smaller (less than M 6.0) damaging earthquakes may be overestimated. Pilot and calibration studies have not yet provided an adequate test concerning the possible extent and effects of landsliding. The indirect economic loss module is new and experimental. While output from pilot studies has generally been credible, this module requires further testing. The databases that HAZUS draws from to make its estimates are often incomplete or outdated (as discussed above, efforts were made to improve some of the datasets used for the analysis, but for some estimates, the software still relies on 1990 census tracts data and 1994 Dunn & Bradstreet economic reports). This is another reason the loss estimates should not be taken at face value. • 2.9.1 Methodology, Terminology and Input Data Used in the Earthquake Loss Estimations for the City The flow chart in Figure 2-4 illustrates the modules (or components) of a HAZUS analysis. The HAZUS software uses population data by census tract and general building stock data from Dunn & Bradstreet (DNB). Essential facilities and lifeline inventory are located by latitude and longitude. However, the HAZUS inventory data for lifelines and utilities were developed at a national level and where specific data are lacking, statistical estimations are utilized. Specifics about the site -specific inventory data used in the models are discussed further in the paragraphs below. Other site -specific data used include soil types and liquefaction susceptible zones. The user then defines the earthquake scenario to be modeled, including the magnitude of the earthquake, and the location of the epicenter. Once all these data are input, the software calculates the loss estimates for each scenario. The loss estimates include physical damage to buildings of different construction and occupancy types, damage to essential facilities and lifelines, number of after -earthquake fires and damage due to fire, and the amount of debris that is expected. The model also estimates the direct economic and social losses, including casualties and fatalities for three different times of the day, the number of people left homeless and number of people that will require shelter, number of hospital beds available, and the economic losses due to damage to the places of businesses, loss of inventory, and (to some degree) loss of jobs. • The indirect economic losses component is still experimental; the calculations in the software are checked against actual past earthquakes, such as the 1989 Loma Prieta and Earth Consultants International Seismic Hazards Page 2-52 2003 Data In Inventory Census -Tract Based Site-Sttetific 1 1990 Census 1 Essential and Demographics High Potential Data Loss Facilities General Lifeline - Building Stock Transportation (1994 D&B Systems occupancy data) Lifeline - Utility Systems User -defined (URA inventory, etc.) Physical Damage r Building damage based on building type Debris generat ion Damageto essential fad lit ies and lifelines Damage to different structural types Fire -after - earthquake Earth Consultants Intem tonal Project Number. 2112 Date. July, 2003 zard M aps Maps Soil Types Deterministic Liquefaction Probabilistic Susceptibility Landslide User -defined Susceptibility (Shake Maps) Data Out IF LOSS Analysis Estimates Direct Economid Social Losses i Casualties and fataldiesat 3times of day People left home- less, in need of shelter Hospital beds available Economic losses due to st r uctural and non-structural losses Lossof business content and bus ness inventory Indirect Economic Losses (still experimental) i Interrupt ions in operation Broken links between suppliers and costumers Employment and income changes Generalized Flow Chart Summarizing the HAZUS Methodology Ground motions from earthquake scenario(s) Fire -after - earthquake wind effects Ground deformation (liquefaction, landslides) Figure 2-4 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 1994 Northridge earthquake, but indirect losses are hard to measure, and it typically takes years before these monetary losses can be quantified with any degree of accuracy. Therefore, this component of HAZUS is still considered experimental. n U • Critical Facilities: HAZUS breaks critical facilities into two groups: essential facilities and high potential loss (HPL) facilities. Essential facilities provide services to the community and should be functional after an earthquake. Essential facilities include hospitals, medical clinics, schools, fire stations, police stations and emergency operations facilities. The essential facility module in HAZUS determines the expected loss of functionality for these facilities. The damage probabilities for essential facilities are determined on a site -specific basis (i.e., at each facility). Economic losses associated with these facilities are computed as part of the analysis of the general building stock. Data required for the analysis include occupancy classes (current building use) and building structural type, or a combination of essential facilities building type, design level and construction quality factor. High potential loss facilities include dams, levees, military installations, nuclear power plants and hazardous material sites. Transportation and Utility Lifelines: HAZUS divides the lifeline inventory into two systems: transportation and utility lifelines. The transportation system includes seven components: highways, railways, light rail, bus, ports, ferry and airports. The utility lifelines include potable water, wastewater, natural gas, crude and refined oil, electric power and communications. if site -specific lifeline utility data are not provided for these analyses, HAZUS performs a statistical calculation based on the population served. General Building Stock Type and Classification: HAZUS provides damage data for buildings based on these structural types: Concrete Mobile Home Precast Concrete Reinforced Masonry Bearing Walls Steel Unreinforced Masonry Bearing Walls Wood Frame and based on these occupancy (usage) classifications: Residential Commercial Industrial Agriculture Religion Government and Education Earth Consultants International Seismic Hazards 2003 Page 2-54 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Building Damage Classification - Loss estimation for the general building stock is averaged for each census tract. Building damage classifications range from slight to complete. As an example, the building damage classification for wood frame buildings is provided below. Wood -frame structures comprise the City's most numerous building type. • • Wood, Light Frame: • Slight Structural Damage: Small cracks in the plaster or gypsum -board at corners of door and window openings and wall -ceiling intersections; small cracks in masonry chimneys and masonry veneer. • Moderate Structural Damage: Large cracks in the plaster or gypsum -board at corners of door and window openings; small diagonal cracks across shear wall panels exhibited by small cracks in stucco and gypsum wall panels; large cracks in brick chimneys; toppling of tall masonry chimneys. • Extensive Structural Damage: Large diagonal cracks across shear wall panels or large cracks at plywood joints; permanent lateral movement of floors and roof; toppling of most brick chimneys; cracks in foundations; splitting of wood sill plates and/or slippage of structure over foundations; partial collapse of "room -over - garage" or other "soft -story" configurations; small foundations cracks. • Complete Structural Damage: Structure may have large permanent lateral displacement, may collapse, or be in imminent danger of collapse due to cripple wall failure or failure of the lateral load resisting system; some structures may slip and fall off the foundations; large foundation cracks. Incorporation of Historic Building Code Design Functions - Estimates of building damage are provided for "High", "Moderate" and "Low" seismic design criteria. Buildings of newer construction (e.g., post-1973) are best designated by "High." Buildings built after 1940, but before 1973, are best represented by "Moderate." If built before about 1940 (i.e., before significant seismic codes were implemented), "Low" is most appropriate. A large(� percentage of buildings in the City of Newport Beach fall in the "Moderate" and "High" V� seismic design criteria, but in some sections of the City, such as in West Newport, the Balboa Peninsula and Corona del Mar, many of the buildings fall in the "Low" category. Fires Following Earthquakes - Fires following earthquakes can cause severe losses. In some instances, these losses can outweigh the losses from direct damage, such as collapse of buildings and disruption of lifelines. Many factors affect the severity of the fires following an earthquake, including but not limited to: ignition sources, types and density of fuel, weather conditions, functionality of water systems, and the ability of fire fighters to suppress the fires. A complete fire -following -earthquake model requires extensive input about the readiness of local fire departments and the types and availability (functionality) of water systems. The fire following earthquake model presented here is simplified. With better understanding of fires that will be garnered after future earthquakes, forecasting capability will undoubtedly improve. For additional information regarding this topic, refer to the Fire Hazards Chapter (Chapter 5). Earth Consultants International Seismic Hazards 2003 Page 2-55 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Debris Generation - HAZUS estimates two types of debris. The first is debris that falls in large pieces, such as steel members or reinforced concrete elements. These require special treatment to break into smaller pieces before they are hauled away. The second type of debris is smaller and more easily moved with bulldozers and other machinery and tools. This type includes brick, wood, glass, building contents and other materials. Estimating Casualties - Casualties are estimated based on the assumption that there is a strong correlation between building damage (both structural and non-structural) and the number and severity of casualties. In smaller earthquakes, non-structural damage will most likely control the casualty estimates. In severe earthquakes where there will be a large number of collapses and partial collapses, there will be -a proportionately larger number of fatalities. Data regarding earthquake -related injuries are not of the best quality, nor are they available for all building types. Available data often have insufficient information about the type of structure in which the casualties occurred and the casualty - generating mechanism. HAZUS casualty estimates are based on the injury classification scale described in Table 2-3. Table 2-3: Injury Classification Scale Injury Severity Injury Description Level Severity 1 Injuries requiring basic medical aid without requiring hospitalization. Severity 2 Injuries requiring a greater degree of medical care and hospitalization, but not expected to progress to a life -threatening status. Severity 3 Injuries which pose an immediate life -threatening condition if not treated adequately and expeditiously. The majority of these injuries are the result of structural collapse and subsequent entrapment or impairment of the occupants. Severity 4 Instantaneously killed or mortally injured. In addition, HAZUS produces casualty estimates for three times of day: Earthquake striking at 2:00 A.M. (population at home) Earthquake striking at2:00 P.M. (population atwork/school) Earthquake striking at 5:00 P.M. (commute time). Displaced Households/Shelter Requirements - Earthquakes can cause loss of function or habitability of buildings that contain housing. Displaced households may need alternative short-term shelter, provided by family, friends, temporary rentals, or public shelters established by the City, County or by relief organizations such as the Red Cross. Long-term alternative housing may require import of mobile homes, occupancy of vacant units, net emigration from the impacted area, or, eventually, the repair or reconstruction of new public and private housing. The number of people seeking short-term public shelter is of most concern to emergency response organizations. The longer -term impacts on the housing stock are of great concern to local governments, such as cities and counties. . Earth Consultants International Seismic Hazards Page 2-56 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Economic Losses - HAZUS estimates structural and nonstructural repair costs caused by building damage and the associated loss of building contents and business inventory. Building damage can cause additional losses by restricting the building's ability to function properly. Thus, business interruption and rental income losses are estimated. HAZUS divides building losses into two categories: (1) direct building losses and (2) business interruption losses. Direct building losses are the estimated costs to repair or replace the damage caused to the building and its contents. Business interruption losses are associated with inability to operate a business because of the damage sustained during the earthquake. Business interruption losses also include the temporary living expenses for those people displaced from their homes because of the earthquake. Earthquakes may produce indirect economic losses in sectors that do not sustain direct damage. All businesses are forward -linked (if they rely on regional customers to purchase their output) or backward -linked (if they rely on regional suppliers to provide their inputs) and are thus potentially vulnerable to interruptions in their operation. Note that indirect losses are not confined to immediate customers or suppliers of damaged enterprises. All of the successive rounds of customers of customers and suppliers of suppliers are affected. In this way, even limited physical earthquake damage causes a chain reaction, or ripple effect, that is transmitted throughout the regional economy. 2.9.2 HAZUS Scenario Earthquakes for the Newport Beach Area Four specific scenario earthquakes were modeled using the HAZUS loss estimation software available from FEMA: earthquakes on the San Joaquin Hills, Newport -Inglewood, Whittier, and San Andreas faults (see Table 2-4). • The four earthquake scenarios modeled for this study are discussed in the following sections. An earthquake on the San Andreas fault is discussed because it has the highest probability of occurring in the not too distant future, even though the loses expected from this earthquake are not the worst possible for Newport Beach. An earthquake on the San Andreas fault has traditionally been considered the 'Big One," the implication being that an earthquake on this fault would be devastating to southern California. However, there are several other seismic sources that, given their location closer to coastal Orange County, would be more devastating to the region, even if the causative earthquake is smaller in magnitude than an earthquake on the San Andreas fault. The San Joaquin Hills Blind Thrust was only discovered in the late 1990s and its geometry and behavior are not well constrained. However, an earthquake on this fault, due to its blind thrust geometry and location has the potential to be more damaging to Newport Beach than rupture of the Newport -Inglewood fault. Typically, earthquakes on thrust faults produce greater vertical accelerations than comparably sized strike -slip earthquakes (such as one on the Newport -Inglewood fault) and vertical motions are more damaging to structures. Scientists have suggested the San Joaquin Hills blind thrust fault couldproduce a magnitude 6.8 to 7.3 earthquake. We took an average and used M 7.1 for our modeling because further research is needed to better understand the seismic character of the San Joaquin Hills fault. • Prior to the discovery of the San Joaquin Hills fault, the Newport -Inglewood fault was thought to pose the greatest threat to Newport Beach because of its close proximity to the Earth Consultants International Seismic Hazards Page 2-57 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • City, its historic activity, and its recurrence interval. Plate 2-2 shows that the northern trace of the Newport -Inglewood fault is 2 miles offshore of Reef Point, comes onshore about 1/2 mile southeast of Newport Pier, and crosses directly beneath downtown and West Newport. The Newport -Inglewood fault is also active; it generated the 1933 M,,, 6.4 earthquake. The epicenter was located only a mile from Newport Beach on the western side of the Santa Ana River. This earthquake did not rupture the surface, but substantial liquefaction -induced damage was reported from Long Beach to Huntington Beach. The earthquake caused 120 deaths, and over $50 million in property damage (Wood, 1933). The Newport -Inglewood fault is also thought to have generated as many as five surface rupturing earthquakes in the last about 11,700 years (Grant et al., 1997;. Shlemon et al., 1995). • Table 2-4: HAZUS Scenario Earthquakes for the City of Newport Beach Fault Sourcc Magnitude Description Worst -case scenario for Newport Beach. This fault's blind thrust geometry would produce greater vertical accelerations than a comparable strike -slip San Joaquin 71 event (e.g. Newport -Inglewood) and vertical motions are more damaging to Hills structures. Note that the San Joaquin Hills fault properties are not well understood (because it was recently discovered) and therefore HAZUS results should be interpreted with caution. Previous worst -case scenario for the City of Newport Beach area because of Newport- 6.9 the close proximity of this fault. The Newport -Inglewood fault parallels the Inglewood coast only a few miles offshore of southern Newport Beach and comes onshore directly beneath West Newport. This fault lies about 20 miles north of the City and could cause significant damage in Newport Beach. The 6.8 magnitude earthquake modeled is in Whittier 6.8 the middle of the size range of earthquakes that researchers now believe this fault is capable of generating. San Andreas A large earthquake that ruptures multiple segments of the San Andreas fault 1857 7.8 is modeled because of its high probability of occurrence, even though the earth uake epicenter would be relatively far from the City. The Whittier fault is the northern extension of the Elsinore fault and is located approximately 20 miles north of the city of Newport Beach (Figure 2-1). No major historical earthquakes have been attributed to the Whittier fault. However, trenching studies have documented recurrent movement of this fault in the last 17,000 years (Lath et al., 1992; Patterson and Rockwell, 1993). Based on these studies, the Whittier fault is thought to be moving at a rate of about 2.5 +/- 1 mm/yr. The Southern California Earthquake Center (1995) determined there is a five percent chance of an earthquake occurring on the Whittier fault by 2024. The Whittier fault is thought capable of producing a magnitude 6.8 maximum magnitude earthquake, although some investigators propose an even larger magnitude 7.1 quake. We used the more conservative magnitude 6.8 earthquake in the HAZUS model. We used data from the historic 1857 Fort Tejon earthquake to model the effects of a very large San Andreas earthquake on Newport Beach. Although the 1857 quake nucleated on the Carrizo segment, we place our modeled M 7.8 epicenter closest to Newport Beach (on . Earth Consultants International Seismic Hazards Page 2-58 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • the southern part of the Mojave segment) because this will yield the maximum possible damage caused by a San Andreas earthquake. n U 2.9.3 Inventory Data Used in the HAZUS Loss Estimation Models for Newport Beach As mentioned previously, the population data used for the analyses were modified using the recently available 2000 Census data. The general building stock and population inventory data conform to census tract boundaries, and the census tract boundaries generally conform to City limits, with some exceptions. The region studied is 54 square miles in area and contains 21 census tracts. There are over 35,000 households in the region, with a total population of 80,000 (based on 2000 Census Bureau data). There are an estimated 29,000 buildings in the region with a total building replacement value (excluding contents) of $8 billion (1994 dollars). Approximately 93 percent of the buildings (and 54 percent of the building value) are associated with residential housing (see Figure 2-5). In terms of building construction types found in the region, wood -frame construction makes up 88 percent of the building inventory. The remaining percentage is distributed between the other general building types. The replacement value of the transportation and utility lifeline systems in the City of Newport Beach is estimated to be nearly $1.72 billion and $224 million (1994 dollars), respectively. Figure 2-5 Building Inventory, by Occupancy Type, in the Newport Beach Area (values shown are in millions of dollars) 465 The HAZUS inventory of unreinforced masonry (URM) buildings included 125 structures, whereas the 2000 Seismic Safety Commission data indicate 126 URMs in Newport Beach. These numbers are in close agreement; therefore we used the URM numbers that HAZUS supplies. However, we did change the seismic design criteria for all of the URMs in the City from low to moderate to reflect the retrofitting efforts that have been accomplished in the late 1990s and early 2000s. It is important to note, however, that retrofitting is typically designed to keep buildings from collapsing, but that structural damage to the building is still possible and expected. We also made changes to the HAZUS hospital inventory for Newport Beach. The number of beds at Hoag Memorial Hospital was • Earth Consultants International Seismic Hazards Page 2-59 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • increased from 355 to 403 (number of beds at the hospital as reported by Ms. Alison Taylor of the Hoag Hospital Engineering Department). Regarding critical facilities, the HAZUS database for Newport Beach includes 38 schools, 1 fire station, 1 police station, and no emergency operations center. We modified the school data to include 26 schools or school facilities, including school district offices, private schools, and community colleges that fall within City limits. HAZUS reports a larger number of schools because its data come from the census tracts, which extend beyond the Newport Beach City limits. The City's emergency operations center in the auditorium of the police station was also added. The database was further modified to include the eight fire stations that serve the City. The locations of these facilities are shown on Plate 2-4. 2.9.4 Estimated Losses Associated with the Earthquake Scenarios HAZUS loss estimations for the City of Newport Beach based on the modeled earthquake scenarios are presented concurrently below. These scenarios include earthquakes on the San Joaquin Hills, Newport -Inglewood, Whittier, and San Andreas faults. Of the four earthquake scenarios modeled for the City, the results indicate that the San Andreas fault poses the least damage to the Newport Beach area, although this fault may have the highest probability of rupturing in the near -future. Given its proximity, fault type and magnitude of its maximum earthquake, the San Joaquin Hills fault has the potential to cause the worst -case scenario for the City. The San Joaquin . Hills structure is a reverse fault that is thought to be responsible for uplift of the San Joaquin Hills. It may have caused the greater than magnitude 7 earthquake reported by the Portola expedition in 1769 (Grant et al., 2002). In general, reverse earthquakes generate stronger ground accelerations that are distributed over broader geographic areas than similar -magnitude strike -slip earthquakes. The Newport -Inglewood earthquake scenario is the next worst -case scenario; it has the potential to cause significant damage in the city of Newport Beach. The losses anticipated as a result of the Whittier fault causing an earthquake are an order of magnitude lower than the scenario just discussed. Building Damaee - HAZUS estimates that between approximately 450 and 13,000 buildings will be at least moderately damaged in response to the earthquake scenarios presented herein, with the lower number representative of damage as a result of an earthquake on the San Andreas fault, and the higher number representing damage as a result of an earthquake on the San Joaquin Hills fault. These figures represent about 2 to 44 percent of the total number of buildings in the study area. An estimated 0 to 933 buildings will be completely destroyed. Table 2-5 summarizes the expected damage to buildings by general occupancy type, while Table 2-6 summarizes the expected damage to buildings in Newport Beach, classified by construction type. The data presented in Tables 2-5 and 2-6 show that most of the buildings damaged will be residential, with wood -frame structures experiencing mostly slight to moderate damage. The San Joaquin Hills fault earthquake scenario has the potential to cause at least slight • damage to more than 82 percent of the residential structures in Newport Beach, and moderate to complete damage to as much as 43 percent of the residential stock, whereas, Earth Consultants International Seismic Hazards Page 2-60 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • the Newport -Inglewood scenario has the potential to cause at least slight damage to 65 percent of the residential structures in Newport Beach, and moderate to complete damage to approximately 26 percent of the residential stock. The distribution and severity of the damage caused by these earthquakes to the residential buildings in the City is illustrated in Plate 2-5. The Whittier fault has the potential to cause significant damage to the residential stock of Newport Beach, but the damage would not be as severe as that caused by either the San Joaquin Hills fault or the Newport -Inglewood fault. The San Andreas fault earthquake scenario is anticipated to cause slight to moderate damage to about 9 percent of the residential buildings in the City. The commercial and industrial structures in Newport Beach will also be impacted (Table 2-5). The Newport -Inglewood and San Joaquin Hills earthquakes have the potential to damage about 68 percent and 91 percent of the commercial and industrial buildings, respectively, in the City. The distribution and severity of damage to the commercial structures in the City as a result of earthquakes on the San Joaquin Hills, Newport - Inglewood, and Whittier faults is illustrated in Plate 2-6. All three earthquakes shown on Plate 2-6 are anticipated to cause damage in the commercial district of the City, but an earthquake on the San Joaquin Hills fault would be the most severe, given the fault's type and location beneath the heart of Newport Beach. The HAZUS output shows that URMs in Newport Beach will suffer slight to complete damage, with up to 26 percent likely to be completely destroyed during the worst case San Joaquin Hills earthquake scenario. At first glance this number seems high, however, it is • likely that most of the URMS would have collapsed during this scenario if they had not been retrofitted. The results from the Newport -Inglewood scenario illustrate how resistant the retrofitted URMS are. Only 5 percent of the URMS are likely to be destroyed during the nearly magnitude 7 Newport -Inglewood earthquake. This is anticipated to reduce the number of casualties significantly. The numbers show that by retrofitting its URMs, Newport Beach has already reduced its vulnerability to seismic shaking. Significantly, reinforced masonry, concrete and steel structures are not expected to perform well, with hundreds of these buildings in Newport Beach experiencing at least moderate damage during an earthquake on the San Joaquin Hills or Newport -Inglewood faults. These types of structures are commonly used for commercial and industrial purposes, and failure of some of these structures explains the casualties anticipated during the middle of the day in the non-residential sector (see Table 2-7). These types of buildings also generate heavy debris that is difficult to cut through to extricate victims. • Earth Consultants International Seismic Hazards Page 2-61 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Table 2-5: Number of Buildings Damaged, by Occupancy Type CJ Scenario Occu anc T e Slight Com lete Total Residential 10,466 729 21,945 Commercial 319 162 1,432 Industrial 51 37 275 A riculture 3 :Moderate 1 8 c Reli ion 10 2 34 Government 1 0 2 Education 8 2 24 Total 10.858 933 23,720 Residential 10,5271 5,678 913 256 17,374 0 ° o Commercial 4351 455 166 23 1,079 3 m Industrial 77 89 36 5 207 Agriculture 3 1 0 0 4 Religion 11 11 6 0 28 3 Government 1 0 0 0 1 a Education 8 6 1 0 15 Z Total 11,062 6,240 1,122 284 18,708 Residential 3,593 668 40 01 4,301 Commercial 223 99 10 01 332 y Industrial 43 22 3 01 68 a_ Agriculture 1 0 0 0 1 :a Religion 3 1 0 0 4 Government 0 0 0 0 0 Education 4 1 0 0 5 Total 3,867 791 53 0 4,711 Residential 1,9381 352 33 1 2,324 Commercial 125 47 2 0 174 Industrial 24 13 2 0 39 M Agriculture 1 0 0 0 1 c < Religion 2 0 0 0 2 ro Government 0 0 0 0 0 Education 2 1 0 0 3 Total 2,092 413 37 1 2,543 • Earth Consultants International Seismic Hazards Page 2-62 2003 0 • U 0 0 z 1.0 2.0 -7 1.7 1.8 3.3 3.3 1!6 - 3o - _-- 2.2; .0.8 - 4.8 4.0 1.9 0.8 0.8 1.8 1.8 5.3 1.1 7 9 1.5 0.8 0`5-. 0.8 2.8 1.1 1.6 0.8 0.7 - 1.6 2.5 3.5 1.0 0.8 1.1 1 0 2.7 4.7 Magnitude 7.8 Earthquake on San Andreas Fault vlagnitude 6.8 Earthquake on Whittier Fault 12.5 82 5 41.7 26:2 26.0 3816 8 26.7 29.4 21.3� _ - 25.0 14.3`\ 1. 28.0 44.7 32.4 26.8 23.3 41.1 05 2.6 9.7 15.0 16.2 i J Magnitude 6.8 Earthquake on Newport -Inglewood Fault Magnitude 7.1 Earthquake on San Joaquin Hill Fault EXPLANATION Sources: Federal Emergency Management Agency, HAZUS 99-SR2 Number of Buildings Damaged by Census Tract (labeled with percentage of damaged buildings in census tract) 0-100 201-300 401-600 101-200 301-400 601 and greater 'more than 50% of the residential structure has undergone moderate, extensive and/or complete damage Earth Residential Buildings With At Least Moderate Damage > 50*/* Consultants Plate International (Bused on Four Earthquake Scenarios) 2-5 Project Number: 2112 Date: July,2003 Newport Beach, California HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Table 2-6: Number of Buildings Damaged, by Construction Type • Scenario Structure Type Slight Moderate Extensive Complete Total Concrete 86 122 84 36 328 Mobile Homes 103 411 543 297 1,354 = Precast Concrete 53 138 113 50 354 3 Reinforced Masonry 114 239 192 63 608 b Steel 44 132 105 39 320 c URM 10 36 44 32 122 vi Wood 10,448 8,478 1,292 416 20,634 Total 10,858 9,556 2,373 933 23,720 Concrete 101 108 34 3 246 Mobile Homes 248 512 383 109 1252 $ Precast Concrete 88 129 47 8 272 Reinforced Masonry 148 191 91 8 438 o Steel 73 120 40 4 237 3 URM 31 49 22 6 108 Z Wood 10,373 5,131 505 146 16,155 Total 11,062 6,240 1,122 284 18,708 Concrete 45 18 2 0 65 Mobile Homes 311 233 41 0 585 Precast Concrete 49 28 5 0 82 Reinforced Masonry 61 34 3 0 98 3 Steel 39 17 1 0 57 URM 31 16 1 0 48 Wood 3331 445 0 0 3776 Total 3,867 791 53 0 4,711 Concrete 20 8 1 0 29 Mobile Homes 221 160 33 1 415 Precast Concrete 27 13 1 0 41 1! Reinforced Masonry 31 10 0 0 41 a Steel 28 16 1 0 45 URM 19 7 0 0 26 Wood 1746 196 0 0 1942 Total 2,092 410 36 1 2,539 Casualties - Table 2-7 provides a summary of the casualties estimated for these scenarios. The analysis indicates that the worst time for an earthquake to occur in the city of Newport Beach is during maximum non-residential occupancy (at 2 o'clock in the afternoon, when most people are in their place of business and schools are in session). The San Joaquin Hills earthquake scenario is anticipated to cause the largest number of casualties, followed by an event on the Newport -Inglewood fault. isEarth Consultants International Seismic Hazards Page 2-64 2003 • C� 4.5 rQ 0 n v 1.4 '•o. 4.1 1.3 6.3 6.3 0 Q 2.4' 7.8 0 8.3 Magnitude 7.8 Earthquake on San Andreas Fault 55.0 33.5 Magnitude 6.8 Earthquake on Newport -Inglewood Fault EXPLANATION Number of Buildings Damaged by Census Tract (labeled with percentage of damaged buildings in census tract) �! 0.20 41-60 81 -100 21-40 r 61-80 101 and greater 9.2 Magnitude 6.8 Earthquake on Whittier Fault 57.5 Magnitude 7.1 Earthquake on San Joaquin Hill Fa Sources: Federal Emergency Management Agency, HAZUS 99-SR2 'more than 50% of the residential structure has undergone moderate, extensive and/or complete damage Earth Commercial Buildings With At Least Moderate Damage > 501/o* Plate ConsultantsBased on Four Earthquake Scenarios) International . � 9 2-6 Project Number: 2112 Date: July, 2003 Newport Beach, California • • • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Table 2-7: Estimated Casualties Type and Time of Scenario Level 1: Medical treatment without hospitalization Level 2: Hospitalization but not life threatening Level 3: Hospitalization and life threatening Level 4: Fatalities due to scenario event 4 — 2A.M. Residential (max. residential Non -Residential occupancy) Commute Total 295 61 6 11 61 17 3 5 0 0 1 0 357 79 9 17 = c 'S Cr R c 2 P.M. Residential (max educational, Non -Residential industrial, and Commute commercial) Total 61 12 1 2 1,665 471 76 150 1 1 3 0 1,727 485 80 152 .5 P.M. Residential (peakmmmute Non -Residential time) Commute Total 72 15 1 3 809 229 37 73 4 5 8 2 884 243 46 77 °o 2A M Residential (max. residential Non -Residential occupancy) Commute Total 141 24 2 4 17 4 1 1 0 0 0 0 158 28 3 5 m e ° 2 P.M. Residential (max educational, Non -Residential industrial, and Commute commercial) Total 28 5 0 1 473 105 14 29 0 0 2 0 502 110 16 29 Z 5 P.M. Residential (peak commute Non -Residential time) Commute Total 1 34 6 0 1 223 48 7 13 1 2 3 1 258 1 56 10 15 2A.M. Residential (max. residential Non -Residential occupancy) Commute Total 11 1 0 0 2 _ 0 0 O 0 0 0 0 13 1 0 0 m 2 P.M. Residential (max educational, Non -Residential industrial, and Commute commercial Total 2 0 0 0 47 5 0 0 0 0 0 0 49 5 0 0 5 P.M. Residential (peak commute Non -Residential time) Commute Total26 1 3 0 0 0 23 1 2 0 0 0 0 0 0 2 0 0 2A.M. Residential (max. residential Non -Residential occupancy) Commute Total 6 1 0 0 1 0 0 0 0 0 0 0 7 1 0 0 y G e 2 P.M. Residential (max educational, Non -Residential industrial, and Commute commercial Total 1 0 0 0 26 3 0 0 0 0 0 0 27 3 0 0 5 P.M. Residential (peak commute Non -Residential time) Commute Total 1 D 0 0 13 2 0 0 1 0 0 0 0 1 14 2 0 0 Earth Consultants International Seismic Hazards Page 2-66 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Essential Facility Damage - The loss estimation model calculates the total number of hospital beds in Newport Beach that will be available after each earthquake scenario. A maximum magnitude earthquake on the San Joaquin Hills fault is expected to impact Hoag Hospital such that only 11 percent of the hospital beds (44 beds) would be available for use by existing patients and injured persons on the day of the earthquake. One week after the earthquake, about 26 percent of the beds are expected to be back in service. After one month, 56 percent of the beds are expected to be operational. On the day of the Newport -Inglewood earthquake, the model estimates that only 85 hospital beds (21 percent) will be available for use by patients already in the hospital and those injured by the earthquake. After one week, 40 percent of the beds will be back in service. After thirty days, 69 percent of the beds will be available for use. An earthquake on the Whittier fault is significantly better regarding the availability of hospital beds. The model estimates that only 330 hospital beds (82 percent) will be available on the day of the earthquake. After one week, 90 percent of the hospital beds are expected to be available for use, and after one month, 96 percent of the beds are expected to be operational. An earthquake on the San Andreas fault is not expected to cause significant damage to Hoag Hospital. On the day of the earthquake, the model estimates that 89 percent of the beds will be available for use; after one week, 94 percent of the beds will be available for • use; and after 30 days, 99 percent of the beds will be operational. Given that the models estimate that about 565 people in the Newport Beach area will require hospitalization after an earthquake on the San Joaquin Hills fault (see Table 2-7), Hoag Hospital is not expected to have enough beds to meet the demand for medical care (the model estimates only 40 beds will be available at this hospital after the scenario earthquake). However, nearby cities, such as Irvine, Santa Ana, and Fountain Valley may sustain less damage and people requiring hospitalization could be treated at medical facilities in these cities. HAZUS also estimates the damage to other critical facilities in the City, including schools, fire and police stations, and the emergency operations center. According to the model, earthquakes on the San Andreas and Whittier faults will cause only slight damage to the schools, fire and police stations, and the City's emergency operations center. All of these facilities would be greater than 80 percent functional the day after the earthquake. An earthquake on the San Joaquin Hills fault is anticipated to cause at least moderate damage to all 26 schools in the City, and none of the schools and school district offices in Newport Beach are expected to be more than 50 percent operational the day after the earthquake. The model also indicates that Hoag Hospital, the police station, and all 8 fire stations will experience more than slight damage and none of these facilities will be more than 50 percent operational the day after the earthquake. • Less damaging, an earthquake on the Newport -Inglewood fault is anticipated to cause at least moderate damage to 7 schools in the City. The model also shows that Hoag Hospital Earth Consultants International Seismic Hazards Page 2-67 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • and the 32nd Street fire station will experience more than slight damage and the hospital, emergency operation center, police, and all fire stations will be less than 50 percent operational the day after the earthquake. The modeled earthquakes on the Whittier and San Andreas faults will not damage or cause delays to any of the critical facilities in the City of Newport Beach. Economic Losses - The model estimates that total building -related losses in the city of Newport Beach will range from $65 million for an earthquake on the San Andreas fault, to $2,082 million for an earthquake on the San Joaquin Hills fault. Approximately 25 percent of these estimated losses would be related to business interruption in the City. By far, the largest loss would be sustained by the residential occupancies that make up as much as 43 percent of the total loss. Table 2-8 below provides a summary of the estimated economic losses anticipated as a result of each of the earthquake scenarios considered herein. Table 2-8: Estimated Economic Losses Scenario Property Damage Business Interruption Total San Joaquin Hills $1,513 million $568 million $2,082 million Newport- Inglewood $799 million $264 million $1,063 million Whittier $117 million $34 million $151 million San Andreas $48 million $17 million $65 million • Shelter Requirement - HAZUS estimates that approximately 2,200 households in Newport Beach may be displaced due to the San Joaquin Hills earthquake modeled for this study (a household contains four people, on average). About 1,000 people will seek temporary shelter in public shelters. The rest of the displaced individuals are anticipated to seek shelter with family or friends. An earthquake on the Newport -Inglewood fault is anticipated to displace over 1,000 households, with approximately 500 people seeking temporary shelter. The San Andreas and Whittier earthquakes are not expected to displace any households. Table 2-9: Estimated Shelter Requirements Scenario Displaced Households People Needing Short -Term Shelter San Joaquin Hills 2,159 987 Newport -Inglewood 1,021 461 Whittier 0 0 San Andreas 1 0 1 0 • Earth Consultants International Seismic Hazards Page 2-68 2003 CJ i � I I I I \1\ho' \ ~ \ of-str tures'with,at least-- No school stroctures vtrith at -at \ . o 5Q/o_ od� to or%re,\at/er damage j �l o __ 50 A mode` ; g�i eater damage Magnitude 7.8 Earthquake on Andreas Magnitude 6.8 Earthquake on 'ttier Fault 1 ( Magnitude 6.8 Earthquake on port -Ingle ault Magnitude 7.1 Earthquake on n Joaquin ult Sources: Federal Emergency Management Agency; HAZUS 99-SR2 EXPLANATION ® Location of school with at least moderate damage "more than 50% of the school structures have undergone moderate, extensive and/or complete damage = Ealil a nsultants 4% Schools With At Least Moderate Damage > 50%* Plate Jda- Intemational Based on Four Earthquake Scenarios 9 2-7 Project Number:2112 Date: July,2003 Newport Beach, California HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA I Transportation Damage — Damage to transportation systems in the City of Newport Beach is based on a generalized inventory of the region, which includes areas outside of the City of Newport Beach since the transportation network extends beyond corporate boundaries. Road segments are assumed to be damaged by ground failure only; therefore, the numbers presented herein may be low given that, based on damage observed from the Northridge and San Fernando earthquakes, strong ground shaking can cause considerable damage to bridges. Economic losses to the region due to bridge damage are estimated at between $3.1 million (for an earthquake on the San Andreas fault) to $57.4 million for an earthquake on the San Joaquin Hills fault It is important to note, however, that many of the bridges in the City have been upgraded in the last ten years, and that the HAZUS inventory is based on data that are nine to 13 years old (dating from 1990 to 1994). Therefore, the HAZUS results reported herein may overestimate the damage to bridges in the area. Based on discussions with the City of Newport Beach Engineering Department, those bridges that have not yet been modified are currently being analyzed. Based on the results of these analyses, seismic retrofitting will be performed (Mr. Lloyd Dalton, City of Newport Beach Engineering Department, personal communication). Table 2-10: Expected Damage to Transportation Systems With At >50• Replacement Least With percent Scenario System Segments in value for All Moderate Complete Economic Functional Inventory Segments in Damage Damage Loss ($M) after 1 Day Inventory Major M = Highway Roads 15 $1.3 Billion 0 0 15 T Bet d es 78 $310 Million 1 38 16 1 7.4 41 e Airport Facilities 4 $14 Million 3 0 5.5 4 e Major c$ Highway Roads 15 $t.3 Billion 0 0 0 15 Z Brid es 78 $310 Million 15 4 15.7 71 G Airport Facilities 4 $14 Million 2 0 3.5 2 Major Highway Roads 15 $1.3 Billion 0 0 0 15 3 Bridges 78 $310 Million 3 0 3.4 78 At ort Facilities 4 $14 Million 0 0 0.9 4 Major c Highway Roads 15 $1.3 Billion 0 0 0 15 e Bridges 78 $310 Million 3 0 3.1 78 Airport Facilities 4 $14 Million 4 0 The San Andreas fault earthquake scenario estimates that only 3 of the 78 bridges in the region will experience at least moderate damage, with none of these damaged bridges located within the City of Newport Beach. The impacted bridges in the region are expected • Earth Consultants International Seismic Hazards Page 2-70 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • to be more than 50 percent functional by the next day. The San Andreas earthquake scenario indicates that the airport facilities will experience small economic losses ($0.2 million), but airport functionality will not be impaired. Alternatively, an earthquake on the San Joaquin Hills fault is expected to damage about 38 bridges in the region, with 16 of them considered to be completely damaged. Of the damaged bridges, nine of these are expected to be located within or at the City boundaries. Temporary repairs are expected to make 41 of the damaged bridges in the region more than 50 percent functional one day after the earthquake. Seven days after the earthquake, 51 out of the 78 bridges in the region would be more than 50 percent functional. John Wayne Airport is expected to incur losses of about $5.5 million, but the airport will be functional. The San Joaquin Hills fault earthquake scenario is the worst -case for the transportation system in the City. The damage to bridges as a result of all four earthquake scenarios is illustrated in Plate 2-8. The Whittier fault earthquake scenario models some damage to the regional transportation system, but much less than that caused by either the Newport -Inglewood or San Joaquin Hills earthquakes. None of the bridges in Newport Beach are expected to be experience at least moderate damage as a result of the scenario earthquake on the Whittier fault Utility System_ s _ _Damage -The HAZUS inventory for the Newport Beach area does not include specifics regarding the various lifeline systems in the City, therefore, the model estimated damage to the potable water and electric power using empirical relationships based on the number of households served in the area. The results of the analyses regarding the functionality of the potable water and electric power systems in the City for • the four earthquakes discussed herein are presented in Table 2-11. According to the models, all of the earthquake scenarios will impact the electric power systems; thousands of households in the City are expected to not have electric power even three days after an earthquake on any of the faults discussed in this report. An earthquake on the San Joaquin Hills fault is anticipated to leave more than 14,000 households without electricity for more than one week. Table 2-11: Expected Performance of Potable Water and Electricity Services Scenario Utility Number of Households without Service" Day 1 Day 3 Day 7 Day 30 Day 90 San Joaquin Potable Water 30,415 29,983 29,338 1 23,160 0 Hills Electricity 30,790 24,971 14,286 2,110 72 Newport- Potable Water 14,593 13,021 9,587 0 0 Inglewood Electricity 35,415 19,023 8,860 737 71 Potable Water 7 0 0 0 0 Whittier Electricity 8,099 1,710 201 72 71 Potable Water 17 0 1 0 0 0 San Andreas Electricity 2,919 1 309 1 78 71 71 *Based on Total Number of Households = 35,415. . Earth Consultants International Seismic Hazards Page 2-71 2003 U • No irb dges damaged ' , Magnitude 7.8 Earthquake on Andreas Magnitude 6.8 Earthquake on 'ttier Fault • of /1 Magnitude 6.8 Earthquake on port-Ingl ault Magnitude 7.1 Earthquake on n Joaquin ult Sources. Federal Emergency Management Agency, HAZUS 99-SR2 EXPLANATION Bridge Damage • At least Moderate Damage Complete Damage _y Earth Bridge Damage Ctematan -_�= Intematanal (Based on Four Earthquake Scenarios) Plate 2 _8 ,,„ Project Number: 2112 Date. July, 2003 Newport Beach, California HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The potable water system is anticipated to be significantly impacted, with nearly 30,000 households without water for at least 3 days after the earthquake. These results suggest that the City will have to truck in water into some of the residential neighborhoods until the damages to the system are repaired. Residents are advised to have drinking water stored in their earthquake emergency kits, enough to last all members of the household (including pets) for at least a week. Fire Following Earthquake - HAZUS uses a Monte Carlo simulation model to estimate the number of ignitions and the amount of burnt area as a result of an earthquake. For the earthquake scenarios ran for Newport Beach, HAZUS estimates between 12 and 1 ignitions immediately following an earthquake, with the San Andreas fault earthquake scenario triggering 1 ignitions, the Whittier fault causing 3 ignitions, the Newport - Inglewood igniting 9 fires and the San Joaquin Hills faults triggering 12 ignitions. The burnt area resulting from these ignitions will vary depending on wind conditions. Normal wind conditions of about 10 miles per hour (mph) are expected to result in burn areas of between 1.3 and 24.1 percent of the region's total area. If Santa Ana wind conditions are present at the time of the earthquake, the burnt areas can be expected to be significantly larger. For example, the fire triggered by an earthquake on the San Andreas fault is not expected to displace any people (if the winds are low), but if winds as strong as 30 miles per hour (mph) are present at the time of the earthquake, about 300 people may be displaced. The • model also estimates that the fire would cause about $20 million in building damage. As indicated in the paragraph above, an earthquake on the San Joaquin Hills fault may trigger 12 ignitions. If Santa Ana wind conditions are present at the time, the resultant fires may displace 1,900 people and cause about $130 million dollars of building damage. The other two earthquakes scenarios would cause fire damage in between these two extremes. Additional information regarding fires after earthquakes and the resultant losses estimated for the City of Newport Beach are provided in Chapter 5. Debris Generation - The model estimates that a total of 30 to 1,610 thousand tons of debris will be generated. Of the total amount, brick and wood comprise 30 percent of the total, with the remainder consisting of reinforced concrete and steel. If the debris tonnage is converted to an estimated number of truckloads, it will require 1,000 to 65,000 truckloads (assuming 25 tons/truck) to remove the debris generated by the earthquakes modeled. 2.10 Reducing Earthquake Hazards in the City of Newport Beach This section identifies and discusses the opportunities available for seismic upgrading of existing development and capital facilities, including potentially hazardous buildings and other critical facilities. Many of the issues and opportunities available to the City apply to new development as well as redevelopment and infilling. Issues involving rehabilitation and strengthening of existing development are decidedly more complex given the economic and societal impacts inherent to these issues. . Prioritizing rehabilitation and strengthening projects requires that the City consider where its resources would be better spent to reduce earthquake hazards in the existing development, and Earth Consultants International Seismic Hazards Page 2-73 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • how the proposed mitigation programs can be implemented so as not to cause undue hardship on the community. Rehabilitation programs should target, on a priority basis, potentially hazardous buildings, critical facilities, and high -risk lifeline utilities. The City can best address rehabilitation issues. However, the hazard evaluation is intended to define the scope of the problem. Recent earthquakes, with their relatively low loss of life, have demonstrated that the best mitigation technique in earthquake hazard reduction is the constant improvement of building codes with the incorporation of the lessons learned from past earthquakes. The most recent building codes (UBC 1997; CBC 2001) are prime examples of how incorporating past experience can further reduce of the devastating effects of an earthquake. However, while new building codes reduce the hazard, increases in population leading to building in vulnerable areas and the aging of the existing building stock work toward increasing the earthquake hazard of a given region. 2.10.1 1997 Uniform Building Code Impacts on the City of Newport Beach Two significant changes were incorporated into the 1997 Uniform Building Code (UBC — which is the basis for the 2001 California Building Code) that impact the City of Newport Beach. The first change is a revision to soil types and amplification factors, and the second change is the incorporation of the proximity of earthquake sources in UBC Seismic Zone 4, which includes the City of Newport Beach. These changes represent the most significant increases in ground shaking criteria in the last 30 years. The new soil effects are based on • observations made as a result of the Mexico City, Loma Prieta and other earthquakes, and impact all buildings in the City of Newport Beach. In addition, in the current code, soil effects impact buildings of short predominant period of ground shaking (low -rises), whereas in the past, only long -period structures (high-rises) were influenced by UBC requirements. The new ground -shaking basis for code design is now more complicated, however, because of the wide range of soil types and the close proximity of seismic sources. For the City of Newport Beach, these code changes are warranted. Due to the proximity of the Newport -Inglewood and San Joaquin Hills fault systems, the entire area is impacted by the near -source design factors. The 1997 UBC contains detailed descriptions of the incorporation of these new parameters; only a summary is provided below. Soil Types and Soil Amplification Factors: The seismic design response spectra are defined in terms of two site seismic coefficients C. and C,,. These coefficients are determined as a function of the following parameters: Seismic Zone Soil Type, and Near Source Factors (UBC Zone 4 only) The UBC outlines six soil types based on the average soil properties for the top 100 feet of the soil profile. Site -specific evaluation by the project's geotechnical engineer is required to classify the soil profile underlying proposed projects. The soil type parameters are intended to be used by project engineers with Tables 16-5 and 16-T of the 1997 UBC. A Isgeneral description of the 1997 UBC soil types are outlined in Table 2-12, and the soil types in the city of Newport Beach are illustrated in Plate 2-9. Earth Consultants International Seismic Hazards Page 2-74 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Table 2-12 UBC Soil Profile Types Soil Profile Type Soil Profile Name/ Generic Description Average Soil Properties for the Upper 100 Feet Shear Wave Velocity (feet/second) Standard Penetration Test (blows/foot) Undrained Shear Strength (psf) SA Hard Rock >5,000 SB Rock 2,500 to 5,000 Sc Very dense soil and soft rock 1,200 to 2,500 >50 >2,000 So Stiff soil profile 600 to 1,200 15 to 50 1,000 to 2,000 SE Soft soi I profile <600 <15 <1,000 S, Soil requiring site -specific evaluation. Near- Source Factors: The Newport Beach area is subject to near -source design factors given the proximity of several active fault systems. These parameters, new to the 1997 Uniform Building Code (UBC), address the proximity of potential earthquake sources (faults) to the site. These factors were present in earlier versions of the UBC for implementation into the design of seismically isolated structures, but are now included for all structures. The adoption into the 1997 code of all buildings in UBC zone 4 was a • result of the observation of more intense ground shaking than expected near the fault ruptures at Northridge in 1994, and again one year later at Kobe, Japan. The 1997 UBC also includes a near -source factor that accounts for directivity of fault rupture. The direction of fault rupture was observed to play a significant role in distribution of ground shaking at Northridge and Kobe. For Northridge, much of the earthquake energy was released into the sparsely populated mountains north of the San Fernando Valley, while at Kobe, the rupture direction.was aimed at the city and was a contributing factor in the extensive damage. However, the rupture direction of a given source cannot be predicted, and as a result, the UBC requires a general increase in estimating ground shaking of about 20 percent to account for directivity. Seismic Source Tyne: Near source factors also include a classification of seismic sources based on slip rate and maximum magnitude potential. These parameters are used in the classification of three seismic source types (A, B and C) summarized on Table 2-13. IsEarth Consultants International Seismic Hazards Page 2-75 2003 • r LJ This map is Intended for general Iona use piunnme omy. ,murma ion on ,cos map is nrn sufficient to serve as a substitute for detailed geologlc Investigations of Individual sites, far does'd satisfylhe evaluation requirements set forth In geologic hazard regulations. Earth Consultants International (ECI) makes no representations or warranties regarding the accuracy of the data from which these maps were derived. ECI shall not be liable under any circumstances for any direct, indirect, special, Incidental, or consequential damages with respect to any claim by any user or third party on account of, or ansmg from, the use of this map. Soil Profile -.,0•\ Type - �, 5a = Se sf Soil Profile Name/Generic Description Hard Rock Rock Verydense soil and soft rock Stiff sop profile Soft soli profile Average Soil Properties for the Upper 100 feat Shear Wave Velocity (feeUsecond) Standard Penetration Test (t11oWa/foet) Undralned Shear Strength (Pat) >5,000 2,500 to 6,000 1,200to2,500 >60 >2,000 60) to 1,200 <600 Soil requiring she -specific evaluation I\ u _ e 11 1 -1 Pop 1% J 15 to 50 1,000 to 2,000 <15 <1,000 Engineering Soil Types In Accordance wig 1997 Uniform Building Code Newport Beach, California EXPLANATION `• Newport Beach City Boundary Sphere of Influence T Scale: 1:60,000 e•� 0.5 0 0.5 1 1.5 Miles 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from SureIMAPS RASTER Sources: Based on data from Morton (1999). Earth y,,r•r Consultants Intemational Project Number: 2112 Date: July. 2003 „u Plate 2-9 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Table 2-13 Seismic Source Type Seismic Source Definition Seismic Seismic Source Description Maximum Moment Slip Rate, SR Source Magnitude, M (mm/yr.) Type Faults which are capable of producing M > 7.0 and SR 5 A large magnitude events and which have a high rate of seismicity. B All faults other than Types A and C. Faults which are not capable of M < 6.5 SR < 2 C producing large magnitude earthquakes and which have a relatively low rate of seismic activity. Type A faults are highly active and capable of producing large magnitude events. Most segments of the San Andreas fault are classified as Type A. The Type A slip rate (>5 mm/yr) is common only to tectonic plate boundary faults. Type C seismic sources are considered to be sufficiently inactive and not capable of producing large magnitude events such that potential ground shaking effects can be ignored. Type B sources include most of the active faults in California and include all faults that are neither Type A nor C. The 1997 UBC requires that the locations and characteristics of these faults be established based on reputable sources such as the California Geological Survey (CGS — previously known as the California Division of Mines and Geology - CDMG) and the U.S. Geological Survey • (USGS). The CGS classifies the Newport -Inglewood and Whittier faults as Type B faults. The San Joaquin Hills fault has not been classified by CGS, but work done by Grant et al. (2002) indicates it is a Type B fault. To establish near -source factors for any proposed project in the City of Newport Beach, the first step is to identify and locate the known active faults in the region. The International Conference of Building Officials (ICBO) has provided an Atlas of the location of known faults for California to accompany the 1997 UBC. The rules for measuring distance from a fault are provided by the 1997 UBC. The criteria for determining distance to vertical faults, such as the Newport -Inglewood, are relatively straightforward. However, the distance to thrust faults and blind thrust faults is assumed as 0 for anywhere above the dipping fault plane to a depth of 10 kilometers. This greatly increases the areal extent of high ground shaking parameters, but is warranted based on observations of ground shaking at Northridge. Summar : Seismic codes have been undergoing their most significant changes in history. These improvements are a result of experience in recent earthquakes, as well as extensive research under the National Earthquake Hazard Reduction Program (NEHRP). Inclusion of soil and near -field effects in the 1997 UBC represents a meaningful and impactive change put forth by the geoscience community. Seismic codes will continue to improve with new versions of the building code, and as new data are obtained from both past and future earthquakes. • Earth Consultants International Seismic Hazards Page 2-77 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 2.10.2 Retrofit and Strengthening of Existing Structures The UBC is not retroactive, and past earthquakes have shown that many types of structures are potentially hazardous. Structures built before the lessons learned from the 1971 Sylmar earthquake are particularly susceptible to damage during an earthquake, including unreinforced masonry (URM) structures, pre -cast tilt -up concrete buildings, soft -story structures, unreinforced concrete buildings, as well as pre-1952 single-family structures. Other potentially hazardous buildings include irregular -shaped structures and mobile homes. Therefore, while the earthquake hazard mitigation improvements associated with the current building codes address new construction, the retrofit and strengthening of existing structures requires the adoption of ordinances. The City of 'Newport Beach has adopted an ordinance aimed at retrofitting unreinforced masonry buildings (URMs). Other potentially hazardous buildings, such as pre-1971 concrete tilt -up structures and soft -story buildings, can be inventoried next. Potentially hazardous buildings can be identified and inventoried following the recommendations set forth in publications such as "Rapid Visual Screening of Buildings for Potential Seismic Hazards: Handbook and Supporting Documentation" and "A Handbook for Seismic Evaluation of Existing Buildings and Supporting Documentation", both prepared by the Applied Technology Council in Redwood City, California, and supplied by the Federal Emergency Management Agency (FEMA publications 154 and 155, and 175 and 178, respectively). The building inventory phase of a seismic hazard mitigation program should accurately record the potentially hazardous buildings in an area. To do so, a CIS system is • invaluable. The data base should include information such as the location of the buildings, the date and type of construction, construction materials and type of structural framing system, structural conditions, number of floors, floor area, occupancy and relevant characteristics of the occupants (such as whether the building houses predominantly senior citizens, dependent care or handicapped residents, etc.), and information on structural elements or other characteristics of the building that may pose a threat to life. Once buildings are identified as potentially hazardous, a second, more thorough analysis may be conducted. This step may be carried out by local officials, such as the City's building department, or building owners may be required to submit a review by a certified structural engineer that has conducted an assessment of the structural and non-structural elements and general condition of the building, and has reviewed the building's construction documents (if available). The nonstructural elements should include the architectural, electrical and mechanical systems of the structure. Cornices, parapets, chimneys and other overhanging projections should be addressed too, as these may pose a significant threat to passersby, and to individuals who, in fear, may step out of the building during an earthquake. State of repair of buildings should also be noted, including cracks, rot, corrosion, and lack of maintenance, as these conditions may decrease the seismic strength of a structure. Occupancy should be noted as this factor is very useful in prioritizing the buildings to be abated for seismic hazards. For multi -story buildings, large occupancy structures, and critical facilities, the seismic analysis of the structure should include an evaluation of the site -specific seismic isenvironment (e.g., response spectra, estimates of strong ground motion duration, etc.), and an assessment of the building's loads and anticipated deformation levels. The resulting Earth Consultants International Seismic Hazards Page 2-78 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • data should be weighted against acceptable levels of damage and risk chosen by the City for that particular structure. Once these guidelines are established, mitigation techniques available (including demolition, strengthening and retrofitting, etc.) should be evaluated, weighted, and implemented. With the inventory and analysis phases complete, a retrofit program can be implemented. Although retrofit buildings may still incur severe damage during an earthquake, the mitigation results in a substantial reduction of casualties by preventing collapse. The societal and economic implications of rehabilitating existing buildings are discussed in many publications, including "Establishing Programs and Priorities for the Seismic Rehabilitation of Buildings - A Handbook and Supporting Report", "Typical Costs for Seismic Rehabilitation of Existing Buildings: Summary and Supporting Documentation," (FEMA Publications 174 and 173, and 156 and 157, respectively). Another appropriate source is the publication prepared by Building Technology, Inc. entitled "Financial Incentives for Seismic Rehabilitation of Hazardous Buildings - An Agenda for Action (Report and Appendices). The City of Newport Beach should set a list of priorities by which strengthening of the buildings identified as hazardous will be established and conducted. Currently, there are no Federal or State mandated criteria established to determine the required structural seismic resistance capacity of structures. Retrofitting to meet the most current UBC standards may be cost -prohibitive, and therefore, not feasible. The City may develop its own set of criteria, however, this task should be carried out following a comprehensive • development and review process that involves experienced structural engineers, building officials, insurance representatives, and legal authorities. Selection of the criteria by which the structural seismic resistance capacity of structures will be measured may follow a review of the performance during an earthquake of similar types of buildings that had been retrofit prior to the seismic event. Upgrading potentially hazardous buildings to, for example, 1973 standards may prove inefficient if past examples show that similar buildings retrofit to 1973 construction codes performed poorly during a particular earthquake, and had to be demolished anyway. Issues to be addressed include justification for strengthening a building to a performance level less than the current code requirements, the potential liabilities and limitations on liability, and the acceptable damage to the structure after strengthening (FEMA, 1985). The mitigation program established by the City could be voluntary or mandatory. Voluntary programs to encourage mitigation of potentially hazardous buildings have been implemented with various degrees of success in California. Incentives that have been used to engender support among building owners include tax waivers, tax credits, and waivers from certain zoning restrictions. Other cities have required a review by a structural engineer when the building is undergoing substantial improvements. 2.11 Summary Since it is not possible to prevent an earthquake from occurring, local governments, emergency relief organizations, and residents are advised to take action and develop and implement policies . and programs aimed at reducing the effects of earthquakes. Individuals should also exercise prudent planning to provide for themselves and their families in the aftermath of an earthquake. Earth Consultants International Seismic Hazards Page 2-79 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA 0 Earthquake Sources o The City of Newport Beach is located in an area where several active faults have been mapped. At least two active faults extend through portions of the City: the Newport - Inglewood runs beneath Balboa Peninsula, the City Hall area, and West Newport, the San Joaquin Hills fault may extend under the much of eastern Newport Beach. Both fault zones are capable of causing severe damage to the City. Other faults such as the Palos Verdes, Compton and Elysian Park Thrusts, Whittier, and Chino segment of the Elsinore fault zone also have the potential to damage Newport Beach. Given the location of these faults in and near the City, the 1997 Uniform Building Code requires that Newport Beach incorporate near -source factors into the design of new buildings. In addition to the faults above, numerous other active faults, both onshore and offshore, have the potential to generate earthquakes that would cause strong ground shaking in Newport Beach. o Geologists, seismologists, engineers and urban planners typically use maximum magnitude and maximum probable earthquakes to evaluate the seismic hazard of a region, the assumption being that if we plan for the worst -case scenario, smaller earthquakes that are more likely to occur can be dealt with more effectively. o A number of historic earthquakes have caused strong ground shaking in Newport Beach. The 1933 Long Beach earthquake caused significant damage in the City. Desien Earthquake Scenarios: • o Both the Newport -Inglewood and the San Joaquin Hills faults have the potential to generate earthquakes that would be described as worst -case for the City of Newport Beach. The San Joaquin Hills fault is thought capable of generating an earthquake between magnitude 6.8 and 7.3. In this report, a magnitude 7.1 earthquake was modeled to obtain loss estimates for the City. A magnitude 7.3 earthquake would cause even higher losses than those presented here. o A maximum magnitude earthquake on the San Andreas fault was also considered as a likely earthquake scenario given that this fault is thought to have a relatively high probability of rupturing in the not too distant future. The loss estimation model indicates that the damage caused by an earthquake on the San Andreas fault to the City of Newport Beach is small compared to the other earthquakes modeled, but not insignificant. Damages of about $65 million were estimated for Newport Beach if three segments of the San Andreas fault break in a magnitude 7.8 earthquake. Fault Rupture and Secondary Earthquake Effects: o Several active and potentially active faults have been mapped across or under the City, including the Newport -Inglewood fault and the San Joaquin Hills fault. An Alquist-Priolo Earthquake Fault Zone has not been proposed for the portion of the Newport -Inglewood fault that has been mapped within the City (Newport Mesa and Balboa Peninsula) as its location is not well defined. The San Joaquin Hills fault has not been zoned as it is a • "blind" thrust fault that does not reach the surface. Because trenching studies for most redevelopment projects on the Peninsula are not likely (in most cases) to be successful, Earth Consultants International Seismic Hazards Page 2-80 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA mandating these types of investigations is not recommended. However, the public should be made aware of the presence of the mapped fault by requiring disclosure when properties in this area are sold. Critical facilities should not be located on or near the active traces of the Newport -Inglewood fault. Several small, discontinuous faults have been discovered in the eastern (relatively undeveloped) part of Newport Mesa. These faults are not considered to be large enough to generate earthquakes, but instead are most likely fractures that have accommodated small ground displacements in response to a nearly earthquake on the active strand of the Newport -Inglewood fault zone. Nevertheless, because they show indications of small displacements during the last 11,000 years, building setbacks have been recommended o Currently, shallow ground water levels (< 50 feet from the ground surface) are known to occur along the coast, around Newport Bay, and along the major drainages in the Newport Beach area. Shallow ground water perched on bedrock may also be present seasonally in the canyons draining the San Joaquin Hills. Seasonal fluctuations in groundwater levels, and the introduction of residential irrigation requires that site -specific investigations be completed to support these generalizations in areas mapped as potentially susceptible to liquefaction. o Those portions of the Newport Beach area that may be susceptible to seismically induced settlement are the alluvial surfaces and larger drainages that are underlain by late Quaternary alluvial sediments (similar to the liquefaction -susceptible areas). Sites in the • San Joaquin Hills along the margins of the larger drainage channels and an area just west of the Santa Ana River outlet may be particularly vulnerable. o The central and eastern portions of Newport Beach are most vulnerable to seismically induced slope failure, due to the steep terrain. o The California Geological Survey (CGS) has completed mapping in the Newport Beach area under the Seismic Hazards Mapping Act. Geological studies in accordance with the guidelines prepared by the CGS should be followed in those areas identified as having a liquefaction or slope -instability hazard. Earthquake Vulnerability: o Most of the loss of life and injuries that occur during an earthquake are related to the collapse of hazardous buildings and structures, or from non-structural components (contents) of those buildings. o Inventory of potentially hazardous structures, such as concrete tilt -ups, pre 1971- reinforced masonry, soft -story buildings, and pre-1952 wood -frame buildings, is recommended. o Most damage in the City is expected to be to wood -frame residential structures, which amount to more than 57 percent of the building stock in the City. Two of the earthquake • scenarios modeled for this study suggest that as much as 65 percent of the residential buildings in the City will experience at least some damage. However, the damage to Earth Consultants International Seismic Hazards Page 2-81 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • residential structures, although costly, is not expected to cause a large number of casualties. o The loss estimation models indicate that some of the school buildings in the City are likely to be damaged during an earthquake. The Newport -Mesa Unified School District in the process of a 5-year building modernization program that will include seismic upgrades and/or building replacement. The District has completed some surveys to identify problems, however the proposed construction work has not been started yet (Mr. Paul Reed, Newport -Mesa Unified School District, personal communication). Operators of private schools should conduct a structural assessment of their schools and prioritize structural strengthening based on the results of these analyses. Earthquake Hazard Reduction: o The best mitigation technique in earthquake hazard reduction is the constant improvement of building codes with the incorporation of the lessons learned from each past earthquake. This is especially true in areas not yet completely developed, such the Newport Coast Planned Community in the San Joaquin Hills of southeastern Newport Beach. In addition, current building codes should be adopted for re -development projects that involve more than 50 percent of the original cost of the structure. The recent building codes incorporate two significant changes that impact the City of Newport Beach. The first change is a revision to soil types and amplification factors, and the second change is the incorporation of the proximity of earthquake sources in UBC seismic zone 4. However, since the City of . Newport Beach is mostly developed, and building codes are generally not retroactive, the adoption of the most recent building code is not going to improve the existing building stock, unless actions are taken to retrofit the existing structures. Retrofitting existing structures to the most current building code is in most cases cost -prohibitive and not practicable. However, specific retrofitting actions, even if not to the latest code, that are known to improve the seismic performance of structures should be attempted. o All of the Newport Beach area is subject to near -source design factors because the City is traversed by two active fault systems, and is located near at least two other potentially significant seismic sources. These parameters, new to the 1997 Uniform Building Code (UBC) and the 2001 California Building Codes (CBC), address the proximity and the potential of earthquake sources (faults) to the site. o While the earthquake hazard mitigation improvements associated with the 1997 UBC address new construction, the retrofit and strengthening of existing structures requires the adoption of ordinances. The City of Newport Beach has adopted an ordinance aimed at retrofitting unreinforced masonry buildings (URMs). Similar ordinances can be adopted for the voluntary or mandatory strengthening of wood -frame residential buildings, pre -cast concrete buildings, and soft -story structures, among others. Although retrofitted buildings may still incur severe damage during an earthquake, their mitigation results in a substantial reduction of casualties by preventing collapse. o Adoption of new building codes does not mitigate local secondary earthquake hazards • such as liquefaction and ground failure. Therefore, these issues are best mitigated at the local level. Avoiding areas susceptible to earthquake -induced liquefaction, settlement or Consultants International Seismic Hazards Page 2-82 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • slope instability is generally not feasible. The best alternative for the City is to require "special studies" within these zones for new construction, as well as for significant redevelopment, and require implementation of the subsequent engineering recommendations for mitigation. • o Effective management of seismic hazards in Newport Beach includes technical review of consulting reports submitted to the City. For projects within seismic hazard zones, State law requires that the City's reviewer be a licensed engineering geologist and/or civil engineer having competence in the evaluation and mitigation of seismic hazards (CCR Title 14, Section 3724). Because of the interrelated nature of geology, seismology, and engineering, most projects will benefit from review by both the geologist and civil engineer. The California Geological Survey has published guidelines to assist reviewers in evaluating site -investigation reports (CDMG, 1997). Earth Consultants International Seismic Hazards Page 2-83 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • REFERENCES Barrows, A.G., 1974, A Review of the Geology and Earthquake History of the Newport -Inglewood Structural Zone: Southern California: California Division of Mines and Geology Special Report 114, 115p. Barrows, A.G., Irvine, P.J., and Tan, S.S, 1995, Geologic surface effects triggered by the Northridge earthquake; in Woods, M.C., and Seiple, W.R. (editors), The Northridge, California, Earthquake of 17 January 1994: California Division of Mines and Geology Special Publication 116, pp 65-88. Bergmann, M.C., Rockwell, T.K., Kenney, M., Hushebeck, M., Hirabayashi, K., Haraden, C., Thomas, A., and Patterson, A., 1993, Preliminary Assessment of the Late Holocene slip rate for the Wildomar Fault, Murrieta, California: Final Technical Report, U.S. Geological Survey External Research Program under Contract No. 14-08-001-G2062, dated January 19, 1993. Blake, T. F., 2000a, EQFAULT, A Computer Program for the Estimation of Peak Horizontal Ground Acceleration from 3D Fault Sources. Blake, T.F., 2000b FRISKSP, A Computer Program for the Estimation of Median Peak Horizontal Ground Acceleration from 3D Fault Sources. • Blake, T.F., Holligsworth, R.A., and Stewart, J.P., (editors), 2002, Recommended Procedures for Implementation of DMG Special Publication 117, Guidelines for Analyzing and Mitigating Landslide Hazards in California: Southern California Earthquake Center, 110p. + Appendix A. Bolt, Bruce A., 1999, Earthquakes: W.H. Freeman and Company, New York, 331 p. Boore, D.M, Joyner, W. and Fumal, T. E., 1997, Equations for estimating horizontal response spectra and peak acceleration from western North American earthquakes: A summary of recent work: Seismological Research Letters, Vol. 68, No. 1, pp 128-153. Borchardt, G., and Kennedy, M.P., 1979, Liquefaction potential in urban San Diego — a pilot study: California Geology, Vol. 32, pp. 217-221. Bryant, W.A., 1985, Southern Newport -Inglewood Fault Zone, Southern Los Angeles and Northern Orange Counties: California Division of Mines and Geology Fault Evaluation Report FER- 172 (unpublished). Bryant, W.A., 1988, Recently Active Traces of the Newport -Inglewood Fault Zone, Los Angeles and Orange Counties, California: California Division of Mines and Geology Open -File Report 88-14. Bullard, T.F., and Lettis, W.R., 1993, Quaternary fold deformation associated with blind thrust • faulting, Los Angeles basin, California: Journal of Geophysical Research, Vol. 98, pp. 8348-8369. Earth Consultants International Seismic Hazards Page 2-84 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Byerly, P. 1930, The California earthquakes of November 4, 1927: Bulletin of the Seismological Society of America, Vol. 20, pp. 53-66. California Code of Regulations, Title 14, Article 10, Seismic Hazards Mapping Act. California Code of Regulations, Title 24, California Building Standards Code. California Division of Mines and Geology (CDMG), 1976, Environmental Geology of Orange County, California: Division of Mines and Geology Open -file Report 79-8 LA, 474p. California Division of Mines and Geology, 1997a (Revised 2001), Seismic Hazard Zone Report for the Anaheim and Newport Beach 7.5 Minute Quadrangles, Orange County, California, Seismic Hazard Zone Report 003. California Division of Mines and Geology, 1997b (Revised 2001), Seismic Hazard Zone Report for the Laguna Beach 7.5 Minute Quadrangle, Orange County, California, Seismic Hazard Zone Report 013. California Division of Mines and Geology, 1997c (Revised 2001), Seismic Hazard Zone Report for the Tustin 7.5 Minute Quadrangle, Orange County, California, Open -File Report 97-20. California Division of Mines and Geology (CDMG), 1986, Alquist-Priolo Special Studies Zones • Map for the Newport Beach Quadrangle, Effective: July 1, 1986. California Division of Mines and Geology (CDMG), 1996, Probabilistic Seismic Hazard Assessment for the State of California, Appendix A — Fault Source Parameters: Open -File Report 96-08. California Division of Mines and Geology (CDMG), 1997, Guidelines for Evaluating and Mitigating Seismic Hazards in California: Special Publication 117, 74p. California Division of Mines and Geology (CDMG), 1998, Maps of Known Active Near -Source Zones in California and Adjacent Potions of Nevada, to be used with the 1997 Uniform Building Code published by the International Conference of Building Officials. California Division of Mines and Geology (CDMG), 1999, Recommended Criteria for Delineating Seismic Hazard Zones in California: Special Publication 118, May 1992, Revised July 1999. California Geological Survey, 2002, Guidelines for Evaluating the Hazard of Surface Fault Rupture: DMG Note 49, available at http://www.consrv.ca.gov/cgs/information/publications/cgs_notes/index.htm Clark, B.R., Zeiser, F.L., and Gath, E.M., 1986, Evidence for determining the activity level of the Pelican Hill fault, coastal Orange County, California; in Program with Abstracts, • Association of Engineering Geologists, p. 146. Earth Consultants International Seismic Hazards Page 2-85 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Clarke, S.H., Jr., Greene, H.G., and Kennedy, M.P., 1985, Earthquake -related phenomena offshore; in Ziony, I., (editor), Evaluating Earthquake Hazards in the Los Angeles Region: United States Geological Survey Professional Paper 1360, pp. 347-374. Claypole, E.W., 1900, The Earthquake at San Jacinto, December 25, 1899: The American Geologist, Vol. XXV, Feb. 1900, pp. 106-108, plate III. Coffman, J. L., and Stover, C.W., 1993, Seismicity of the United States, 1568-1989: U.S. Geological Survey Professional Paper 1527. Converse Consultants, 1994, Fault study report for the City of Newport Beach Utilities Department, Phase II Expansion Project, 949 w. 16'h Street, Newport Beach, California; CCOC Project No. 94-32177-00, dated September 30, 1994. Corwin, C.H., 1947, West Newport oil field; in Summary of Operations, California Oil Fields, Thirty-second Annual Report of the State Oil and Gas Supervisor: Department of Natural Resources, Division of Oil and Gas, Vol. 32, No. 2, pp. 8-16. Crook Jr., R., Allen, C.R., Kamb, B., Payne, C.M., and R.J. Proctor, 1987, Quaternary geology and seismic hazard of the Sierra Madre and associated faults, western San Gabriel mountains; in Recent Reverse Faulting in the Transverse Ranges, California: U.S. Geological Survey Professional Paper 1339, pp. 27-63, Plates 2.1, 2.2, and 2.3. • Davis, T.L., Namson, J., and Yerkes, R.F., 1989, A cross section of the Los Angeles area: Seismically active fold and thrust belt, the 1987 Whittier Narrows Earthquake, and Earthquake Hazard: Journal of Geophysical Research, Vol. 94, pp. 9644-9664. Dolan, J.F., Sieh, K., Rockwell, T.K., Yeats, R.S., Shaw, J., Suppe, G., Huftile, G., and Gath, E., 1995, Prospects for larger and more frequent earthquakes in greater metropolitan Los Angeles, California: Science, Vol. 267, pp. 199-205. Dolan, J.F., Gath, E.M., Grant, L.B., Legg, M., Lindvall, S., Mueller, K., Oskin, M., Ponti, D.F., Rubin C.M., Rockwell, R. K., Shaw, J.H., Trieman, J.A., Walls, C., and Yeats, R.S. (compiler), 2001, Active Faults in the Los Angeles Metropolitan Region: Report by the Southern California Earthquake Center Group C. Earth Consultants International, Inc., 1997, Fault trenching investigation, Newport -Banning property, Orange County, California, Project No. 978100-019, dated November 25, 1997. Earthquake Engineering Research Institute (EERI), 1986, Reducing Earthquake Hazards: Lessons Learned from Earthquakes: Earthquake Engineering Research Institute, Publication No. 86-02, 208p. Earthquake Engineering Research Institute (EERI), 1994, Northridge Earthquake, January 17, 1994, Preliminary Reconnaissance Report: Oakland, California, 96p. • Earth Technology Corporation (The), 1986, Geological evaluation of faulting potential, West Newport oil field, Orange County, California; Project No. 86-820-01, dated July 31, 1986. Earth Consultants International Seismic Hazards Page 2-86 2003 • • • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Ellsworth, W.L., 1990, Earthquake History, 1769-1989; in Wallace, R.E., (editor), The San Andreas Fault System, California: U.S. Geological Survey Professional Paper 1515. Federal Emergency Management Agency, 1985, FEMA-73, Comprehensive Earthquake Preparedness Planning Guidelines: City: Earthquake Hazard Reduction Series 2, 80p. Federal Emergency Management Agency (FEMA), 1987, FEMA-135, Abatement of Seismic Hazards to Lifelines: Water and Sewer Lifelines and Special Workshop Presentations: Earthquake Hazard Reduction Series No. 2, 181 p. Federal Emergency Management Agency (FEMA), 1987, FEMA-139, Abatement of Seismic Hazards to Lifelines: Proceedings of a Workshop on Development of an Action Plan - Volume 5: Papers on Gas and Liquid Fuel Lifelines: Building Seismic Safety Council; Earthquake Hazard Reduction Series No. 30, 134p. Federal Emergency Management Agency (FEMA), 1988, FEMA-154, Rapid Visual Screening of Buildings for Potential Seismic Hazards: A Handbook: Applied Technology Council (ATC- 21), Earthquake Hazards Reduction Series No. 41, 185p. Federal Emergency Management Agency (FEMA), 1988, FEMA-155, Rapid Visual Screening of Buildings for Potential Seismic Hazards: Supporting Documentation: Applied Technology Council (ATC-21-1), Earthquake Hazards Reduction Series No. 42, 137p. Federal Emergency Management Agency (FEMA), 1988, FEMA-156, Typical Costs for Seismic Rehabilitation of Existing Buildings, Volume 1 - Summary: by Englekirk and Hart Consulting Engineers, Inc., Los Angeles, California; Earthquake Hazard Reduction Series No. 39. Federal Emergency Management Agency (FEMA), 1989, FEMA-173, Establishing Programs and Priorities for the Seismic Rehabilitation of Buildings - Supporting Report: Building Systems Development, Inc., Integrated Design Services and Rubin, Claire B.; Earthquake Hazard Reduction Series No 46, 190p. Federal Emergency Management Agency (FEMA), 1989, FEMA-174, Establishing Programs and Priorities for the Seismic Rehabilitation of Buildings - A Handbook Building Systems Development, Inc., Integrated Design Services and Rubin, Claire B.; Earthquake Hazard Reduction Series No 45, 122p. Federal Emergency Management Agency (FEMA), 1989, FEMA-175, Seismic Evaluation of Existing Buildings: Supporting Documentation: Applied Technology Council (ATC-22-1); Earthquake Hazard Reduction Series No. 48, 160p. Federal Emergency Management Agency (FEMA), 1989, FEMA-178, A Handbook for Seismic Evaluation of Existing Buildings (Preliminary): Applied Technology Council (ATC-22); Earthquake Hazard Reduction Series No. 47, 169p. Earth Consultants International Seismic Hazards 2003 Page 2-87 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Federal Emergency Management Agency, 1998, FEMA-232, Home Builder's Guide to Seismic Resistant Construction: Earthquake Hazard Reduction Series, 75p. Federal Emergency Management Agency, 1998, FEMA-315, Seismic Rehabilitation of Buildings: Strategic Plan 2005: Earthquake Hazard Reduction Series, 40p. Fischer, P.J., and Mills, G.I., 1991, The offshore Newport -Inglewood — Rose Canyon fault zone, California: Structure, segmentation and tectonics; in Abbott, P.L., and Elliot, W.J., (editors.), Environmental Perils, San Diego Region: Geological Society of America Field Trip guidebook prepared by the San Diego Association of Geologists, pp.17-36. Fuis, G.S., and Mooney, W.D., 1990, Lithospheric structure and tectonics from seismic -refraction and other data; in Wallace, R.E., (editor), The San Andreas Fault System, California: U.S. Geological Survey Professional Paper 1515, pp. 207-283. Fumal, T.E., Davis, A.B., Frost, W.T., O'Donnell,)., Sega, G., and Schwartz, D.P., 1995, Recurrence Studies of the Tujunga Segment of the 1971 San Fernando earthquake, California: EOS (Supplement), Vol. 76, No. 46, 364p. Grant, L.B., Waggoner, J.T., Rockwell, T.K., and von Stein, C., 1997, Paleoseismicity of the north branch of the Newport -Inglewood fault zone in Huntington Beach, California, from Cone Penetrometer Test Data: Bulletin of the Seismological Society of America, Vol. 87, No. 2, pp. 277-293. • Grant, L.B., Mueller, K. J., Gath, E.M., Cheng, H., Edwards, R.L., Munro, R., Kennedy, G.L., 1999, Late quaternary uplift and earthquake potential of the San Joaquin Hills, southern Los Angeles Basin, California: Geology, November 1999, Vol. 27, No. 11, pp. 1031-1034, Grant, L.B., Ballenger, L.J., and Runnerstom, E.E., 2002, Coastal uplift of the San Joaquin Hills, southern Los Angeles Basin, California, by a large earthquake since A.D. 1635: Bulletin of the Seismological Society of America, Vol. 92, No. 2, pp. 590-599. Griggs, G.B., Marshall, J.S., Rosenbloom, N.A., and Anderson, R.S., 1991, Ground Cracking in the Santa Cruz Mountains in Baldwin, J.E. and Sitar, N. (editors), Loma Prieta Earthquake: Engineering Geologic Perspectives, Association of Engineering Geologists Special Publication No. 1, pp. 25-41. Guptil, P.D., and Heath, E.G., 1981, Surface faulting along the Newport -Inglewood zone of deformation: California Geology, pp. 142-148. Guptil, P., Armstrong, C., and Egli, M., 1992, Structural features of West Newport Mesa in Heath, E., and Lewis, L., (editors), The Regressive Pleistocene Shoreline, Coastal Southern California, South Coast Geological Society Annual Field Trip Guide Book No. 20, pp. 123- 136. Harp, E.L., and Jibson, R.W., 1996, Landslides triggered by the 1994 Northridge, California, • earthquake: Bulletin of the Seismological Society of America, Vol. 86, No. 1 B, pp. 5319- 5332. Earth Consultants International Seismic Hazards Page 2-88 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Hart, E.W., and Bryant, W.A., 1999, Fault -Rupture Hazard Zones in California, Alquist-Priolo Earthquake Fault Zoning Act with Index to Earthquake •Fault Zones Maps: California Division of Mines and Geology Special Publication 42. Hauksson, E., 1987, Seismotectonics of the Newport -Inglewood fault zone in the Los Angeles Basin, southern California: Bulletin of the Seismological Society of America, Vol. 77, No. 2, pp. 539-561. Hauksson, E, and Jones, L.M., 1989, The 1987 Whittier Narrows earthquake sequence in Los Angeles, southern California: Seismological and tectonic analysis: Journal of Geophysical Research Vol. 94 pp. 9569-9589. Hauksson, E., and Gross, S., 1991, Source parameters of the 1933 Long Beach earthquake: Bulletin of the Seismological Society of America, Vol. 81, pp. 81-98. Hayes, E., 1988, A Review of Information on Seismic Hazards Needed for the Earthquake -Resistant Design of Lifeline Systems in the United States: U.S. Geological Survey Open File Report ICSSCTR-10, 71p. International Conference of Building Officials (ICBO), 1997, Uniform Building Code. International Conference of Building Officials (ICBO), 2001, California Building Code. • Jacoby, G., Sheppard, P. and Sieh, K., 1988, Irregular recurrence of large earthquakes along the San Andreas Fault in southern California -- Evidence from trees near Wrightwood: Science, Vol. 241, pp. 196-199. Jaffe, M., Butler, J., and Thurow, C., 1981, Reducing Earthquake Risks: A Planners Guide: American Planning Association (Planning Advisory Service), Report No. 364, 82p. Jennings, C. W., Strand, R. G., Rogers, T. H., 1977, Geologic Map of California: California Division of Mines and Geology, Geologic Data Map No. 2, reprinted 2000; Scale: 1:750,000. Jennings, Charles W., 1994, Fault Activity Map of California and Adjacent Areas with Location and Ages of Recent Volcanic Eruptions: California Division of Mines and Geology, California Geologic Data Map Series, Map No. 6, Map Scale: 1:250,000. Joyner, W. B., and Fumal, T. E., 1985, Predictive mapping of earthquake ground motion; in Ziony, J. I., (editor), Evaluating Earthquake Hazards in the Los Angeles Region, An Earth -Science Perspective: U.S. Geological Survey Professional Paper 1360, pp. 203-217. Law/Crandall, Inc., 1994, Report of fault rupture hazard investigation, Wastewater Treatment Plant No. 2, Huntington Beach, California for the County Sanitation Districts of Orange County, Project No. 2661.30140.0001, dated June 13, 1994. • Earth Consultants International Seismic Hazards Page 2-89 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Lazarte, C.A., Bray, J.D., Johnson, A.M., and Lemmer, R.E., 1994, Surface breakage of the 1992 Landers earthquake and its effects on structures: Bulletin of the Seismological Society of America, Vol. 84, No. 3, pp 547-561. Legg, M.R., 1985, Geologic structure and tectonics of the inner continental borderland offshore northern Baja California, Mexico: unpublished PH.D thesis, University of California Santa Barbara, 410p. Legg, M.R., and Kennedy, M.P., 1991, Oblique divergence and convergence in the California Continental Borderland; in Abbott, P.L., and Elliott, W.J., (editors), Environmental Perils of the San Diego Region: San Diego Association of Geologists Guidebook, pp. 1-16. Legg, M.R. and Goldfinger, C., 2001, Earthquake Potential of Major Faults Offshore Southern California: Collaborative Research with Oregon State University and Legg Geophysical: U.S. Geological Survey Grant No. 01 HQGR001 7; available at http:Herp- web.er.usgs.gov/reports/abstract/2001/sc/gOO17.htm. Leighton and Associates, Inc., 1997, Preliminary geotechnical investigation of liquefaction and settlement potential, proposed residential development at the lowland portion of Newport/Banning Ranch, northeast of Pacific Coast Highway and the Santa Ana River, city of Newport Beach, California; Project No. 1970011-01, dated May 16, 1997. Lindvall, S.C., and Rockwell, T.K., 1995, Holocene activity of the Rose Canyon fault zone in San • Diego, California: Journal of Geophysical Research, Vol. 100, pp. 24,121-24,132. Lund, Le Val, 1996, Lifeline utilities performance in the 17 January 1994 Northridge, California Earthquake: Bulletin of the Seismological Society of America, Vol. 86, No. 1 B, pp. 5350- 5361. Lund, Le Val, 1994, Lifelines performance in the Landers and Big Bear (California) earthquakes of 28 June 1992: Bulletin of the Seismological Society of America, Vol. 84, No. 3, pp. 562- 572. Martin, G.R., and Lew, M., 1999, (editors), Recommended Procedures for Implementation of DMG Special Publication 117 Guidelines for Evaluating and Mitigating Seismic Hazards in California — Liquefaction Hazards: Southern California Earthquake Center Publication, 63p. McGarr, A., Vorhis, R. C., 1968, Seismic Seiches from the March 1964 Alaska earthquake: U.S. Geological Survey Professional Paper 544-E, 43p. McNeilan, T., Rockwell, T.K., and Resnick, G., 1996, Sense and rate of Holocene slip, Palos Verdes fault, southern California: Journal of Geophysical Research, Vol. 101, B4, pp. 8317- 8334. Millman, D.E., and Rockwell, T.K., 1986, Neotectonics of the Elsinore fault in Temescal Valley, California, in Neotectonics and Faulting in Southern Callifornia, Volume and Guidebook, • Geological Society of America Cordilleran Section, pp. 159-166. Earth Consultants International Seismic Hazards Page 2-90 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA IsMorton, D.M., 1999, Preliminary Digital Geologic Map of the Santa Ana 30' X 60' Quadrangle, Southern California, Version 1.0: United States Geological Survey Open -File Report 99- 172, Southern California Areal Mapping Project. Morton, P.K., Miller, R.V., Evans, J.R., 1976, Environmental Geology of Orange County, California: California Division of Mines and Geology Open -File Report 79-8 LA. Morton, P.K., and Miller, R.V., 1981, Geologic Map of Orange County California, showing Mines and Mineral Deposits: California Division of Mines and Geology Bulletin 204, Plate 1, scale 1:48,000. Mueller, Karl J. and Rockwell, T.K., 1995, Late Quaternary activity of the Laguna Salada fault in northern Baja California, Mexico: Geological Society of America Bulletin, Vol. 107, No. 1, pp. 8-18. Mueller, K.J., 1997, Recency of folding along the Compton -Los Alamitos trend: Implications for seismic risk in the Los Angeles basin: Abstract, EOS Transactions of the American Geophysical Union, Vol. 78, p. 702. Mueller, K.J., Grant, L.B., and Gath, E.M., 1998, Late Quaternary growth of the San Joaquin Hills - A new source of blind thrust earthquakes in the Los Angeles basin: Seismological Research Letters, Vol. 69, pp. 161-162. • Oakeshott, Gordon B., (editor), 1975, San Fernando, California, Earthquake of 9 February 1971: California Division of Mines and Geology, Bulletin 196, 462p. E Palm, R., 1981, Real Estate Agents and Special Studies Zone Disclosure: The Response of California Home Buyers to Earthquake Hazard Information: University of Colorado at Boulder, Natural Hazards Research and Applications Information Center, Monograph Series No. 032. Peterson M. D. and Wesnousky, S.G., 1994, Fault slip rates and earthquake histories for active faults in southern California: Bulletin of the Seismological Society of America, Vol. 84, No. 5, pp. 1608-1649. Peterson, M. D., Bryant, W. A., Cramer, C. H., Cao, T., Reichle, M., Frankel, A. D., Lienkaemper, J. J., McCrory, P.A., and Schwartz, D. P., 1996, Probabilistic Seismic Hazard Assessment for the State of California: California Division of Mines and Geology, Open -File Report 96- 08. Peterson, M. D., Toppozada, T. R., Cao, T., Cramer, C. H., Reichle, M. S. and Bryant, W. A., 2000, Active Fault Near -Source Zones Within and Bordering the State of California for the 1997 Uniform Building Code: Earthquake Spectra, Vol. 16, No. 1, pp. 69-83. Richter, Charles. F., 1958, Elementary Seismology, W. H., Freeman, San Francisco. Earth Consultants International Seismic Hazards Page 2-91 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Rivero, C., Shaw, J.H., and Mueller, 2000, Oceanside and Thirtymile Bank blind thrusts: Implications for earthquake hazards in coastal southern California, Geology, Vol. 28, No. 10, pp. 891-894 Rockwell, T.K., McElwain, R.S., Millman, D.E., and Lamar, D.L., 1986, Recurrent late Holocene faulting on the Glen Ivy north strand of the Elsinore fault at Glen Ivy Marsh; in Neotectonics and Faulting in Southern California, Volume and Guidebook, Geological Society of America Cordilleran Section, pp. 167-175. Rockwell, T.K., 1989, Behavior of individual fault segments along the Elsinore -Laguna Salada fault zone, southern California and northern Baja California: Implications for the charactreristic earthquake model; in Schwartz, D.P., and Sibson, R.H., (editors), Fault Segmentation and Controls of Rupture Initiation and Termination: U.S. Geological Survey Open -File Report OF 89-315, pp. 288-308. Rogers, A. M., Tinsely, J. C., and Borcherdt, R. D., 1985, Predicting relative ground response; in Ziony (editor), Evaluating Earthquake Hazards in the Los Angeles Region, An Earth Science Perspective: U.S. Geological Survey, Professional Paper 1360, pp. 221-248. Roth R., Holtom, R., and Sai-on S., 1986, California Earthquake Zoning and Probable Maximum Loss Evaluation Program, California Administrative Code Title 10, Chapter 5, Subchapter 3, Section 2307: California Department of Insurance, Los Angeles, California, 44p. • Rubin, C.M., Lindvall, S., and Rockwell, T., 1998, Paleoseismic evidence for large slip earthquakes along the Sierra Madre fault in the greater Los Angeles region: Science, Vol. 281, pp. 398- 402. Rubin, C., and Sieh, K., 1992, Active Crustal Shortening Along the Southern Flank of the Central Transverse Ranges, California: Southern California Earthquake Center 1992 Report, Prepared for the SCEC Annual Meeting, October 6-8, 1992, Los Angeles, California. Savage, W.U., 1995, Utility lifelines performance in the Northridge earthquake; in Woods, M.C., and Seiple, W.R., (editors), The Northridge Earthquake of 17 January 1994: California Division of Mines and Geology Special Publication 116, pp. 153-162. Sharpe, R., 1982, An Investigation of the Correlation between Earthquake Ground Motion and Building Performance: Applied Technology Council, U.S. Contract Survey, No. 14-08-0001-19892, 113p. Shaw, J.H. and Suppe, J., 1994, Active faulting and growth folding in the eastern Santa Barbara Channel, California: Geological Society of America Bulletin, Vol. 106, pp. 607-626. Shaw, J. H., and Suppe, J., 1996, Earthquake hazards of active blind -thrust faults under the central Los Angeles basin, California: Journal of Geophysical Research, Vol. 101, pp. 8623-8642. Shaw, J.H., and Shearer, P., 1999, An elusive blind -thrust fault beneath metropolitan Los Angeles: Science, Vol. 283, pp. 1516-1518. Earth Consultants International Seismic Hazards Page 2-92 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Shlemon, R.J., Elliot, P., and Franzen, S., 1995, Holocene displacement history of the Newport - Inglewood, North Branch fault splays, Santa Ana River floodplain, Huntington Beach, California: The Geological Society of America 1995 Annual Meeting, Abstracts with Programs, New Orleans, Louisiana. Sieh, K. and Williams, P., 1990, Behavior of the southernmost San Andreas fault during the past 300 years: Journal of Geophysical Research, Vol. 95, pp. 6629-6645. Sieh, K. L., Jones, L., Hauksson, E., Hudnut, K., Eberhart-Phillips, D., Heaton, T., Hough, S., Hutton, K., Kanamori, H., Lilje, A., Lindvall, S., McGill, S., Mori, J., Rubin, C., Spotila, J., Stock, J., Thio, H. K., Treiman, J., Wernicke, B., Zachariasen, J., 1993, Near field investigations of the Landers earthquake sequence, April to July, 1992: Science, Vol. 260, pp. 171-176. Southern California Earthquake Center (SCEC), 1999, Recommended Procedures for Implementation of DMG Special Publication 117 Guidelines for Analyzing and Mitigating Liquefaction Hazards in California, 63p. Southern California Earthquake Center (SCEC), 2001, Southern California Faults and Earthquakes, World -Wide Web Site: www.scecdc.scec.ora. Southern California Earthquake Center (SCEC), 2002, Recommended Procedures for Implementation of DMG Special Publication 117 Guidelines for Analyzing and Mitigating Landslide Hazards in California; by Blake, T.F., Hollingsworth, R.A., and Stewart, J.P. (editors), 11Op. +Appendix. Spangle, W. E., 1988, Putting Seismic Safety Policies to Work: Prepared for the Bay Area Regional Earthquake Preparedness Project, 39p. Spittler, T.E., Harp, E.L., Keefer, D.K., Wilson, R.C., and Sydnor, R.H., 1990, Landslide features and other coseismic fissures triggered by the Loma Prieta earthquake, Santa Cruz Mountains, California in McNutt, S.R., and Sydnor, R.H., (editors.), The Loma Prieta (Santa Cruz Mountains), California, Earthquake of 17 October 1989: California Division of Mines and Geology Special Publication 104, pp. 59-66. State of California, Office of Planning and Research (OPR), 1987, General Plan Guidelines. State of California, SSC-01, Seismic Safety Commission, 1988, Steps to Earthquake Safety for Local Governments, Report No. SSC 88-01. State of California, SSC-03, Seismic Safety Commission, 1987-03, Guidebook to Identify and Mitigate Seismic Hazards in Building, Report No. SSC 87-03. Stephenson, W.1., Rockwell, T.K., Odum, J.K., Shedlock, K.M., and Okaya, D.A., 1995, Seismic reflection and geomorphic characterization of the onshore Palos Verdes fault zone, Los Angeles, California: Seismological Society of America Bulletin, Vol. 85, No. 3, pp. 943- . 950. Earth Consultants International Seismic Hazards Page 2-93 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Stewart, J.P., Bray, J.D., McMahon, D.J., and Kropp, A.L., 1995, Seismic performance of hillside fills: Reprint from Landslides Under Static and Dynamic Conditions -Analysis, Monitoring, and Mitigation: Geotechnical Engineering Division/ASCE, held October 23-27, 1995, San Diego. Stermitz, F., 1964, Effects of the Hebgen Lake Earthquake on Surface Water: U.S. Geological Survey Professional Paper 435, pp. 139-150. Sudduth, C., 1985, Evaluating earthquake ground failure potential for development decisions, summary of Working Group V and audience discussion; in Future Directions in Evaluating Earthquake Hazards in Los Angeles Region, An Earth -Science Perspective: U.S. Geological Survey, Professional Paper 1360, pp. 320. Teggart, F. J., 1911, The Portola expedition of 1769-1770, Diary of Miguel Costanso, Publication of the Academy of Pacific Coast History, Vol. 2, No. 4. Tinsley, J.C., Youd, T.L., Perkins, D.M., and Chen, A.T.F., 1985, Evaluating liquefaction potential in Ziony, J.I., (editor), Evaluating Earthquake Hazards in the Los Angeles Region — An Earth Science Perspective: U.S. Geological Survey Professional Paper 1360, pp. 263-316. Tinsley, J.C., and Fumal, T.E., 1985, Mapping quaternary sedimentary deposits for aerial variations in shaking response; in Ziony, J.I., (editor), Evaluating Earthquake Hazards in the Los Angeles Region — An Earth Science Perspective: U.S. Geological Survey Professional Paper • 1360, pp. 101-125. Toppozada, T.R., and others, 1988, Planning Scenario for a Major Earthquake on the Newport - Inglewood Fault (Los Angeles and Orange Counties): California Division of Mines and Geology Special Publication No. 99. Toppozada, T.R., Real, C.R., and D.L. Parke, 1981, Preparation of Isoseismal Maps and Summaries of Reported Effects for Pre-1900 California Earthquakes: California Division of Mines and Geology Open File Report 81-11 SAC. Toppozada, T.R. and Parke, D.L., 1982, Areas damaged by earthquakes, 1900-1949: California Division of Mines and Geology, Open -File Report, pp. 82-17. Townley, S.D., 1939, Earthquakes in California, 1769 to 1928: Bulletin of the Seismological Society of America, Vol. 29, No. 1, pp. 21-252. Treiman, J.A., 1995, Surface faulting near Santa Clarita; in Woods, M.C., and Seiple, W.R., (editors), The Northridge, California, Earthquake of 17 January 1994: California Division of Mines and Geology Special Publication 116, pp. 103-110. Tsutsumi, H., Yeats, R.S., and Huftile, G. H., 2001, Late Cenozoic tectonics of the northern Los Angeles fault system, California: Geological Society of America, Vol. 113, No. 4, pp. 454- 468. Earth Consultants International Seismic Hazards Page 2-94 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Tsutsumi, H., and Yeats, R.S., 1999, Tectonic Setting of the 1971 Sylmar and 1994 Northridge earthquakes in the San Fernando Valley, California: Bulletin of the Seismological Society of America, Vol. 89, pp. 1232-1249. Tucker, A.Z., and Dolan, J.F., 2001, Paleoseismologic evidence for a >8 ka age of the most recent surface rupture on the eastern Sierra Madre fault, northern Los Angeles metropolitan region, California: Bulletin of the Seismological Society of America, Vol. 91, pp. 232-249. U. S. Geological Survey, 1935, Newport Beach quadrangle (topographic map), Scale 1:31,680. U. S. Geological Survey, 1948, Tustin, California quadrangle, 7.5 Minute Series (togographic map), Scale 1:24,000. U. S. Geological Survey, 1949, Newport Beach, California, quadrangle, 7.5 X 10 Minute Series (topographic map), Scale 1:24,000. U. S. Geological Survey, 1965 (Photorevised 1981), Newport Beach, California, quadrangle, 7.5 Minute Series (topographic map), Scale 1:24,000. U. S. Geological Survey, 1965 (Photorevised 1981), Laguna Beach, California, quadrangle, 7.5 Minute Series (topographic map), Scale 1:24,000. U. S. Geological Survey, 1965 (Photorevised 1981), Tustin, California quadrangle, 7.5 Minute • Series (topographic map), Scale 1:24,000. U.S. Geological Survey, 1986, Earthquake Hazards in Southern California: Proceedings of XXXII Conference: U.S. Geological Survey Open File Report 86-401, pp. 158-172. Vaughan, P. and Rockwell T.K., 1986, Alluvial stratigraphy and neotectonics of the Elsinore fault zone at Agua Tibia Mountain, Southern California: 82nd Annual Meeting of the Cordilleran Section of the Geological Society of America Field Trip Guidebook, Los Angeles, California, pp. 177-191. Vaughan P.R., Thorup, K.M. and Rockwell, T.K., 1999, Paleoseismology of the Elsinore fault at Agua Tibia Mountain, southern California: Bulletin of the Seismological Society of America, Vol. 89, No. 6, pp. 1447-1457. Wald, D.J., Quitoriano, V., Heaton, T.H., and Kanamori, H., 1999, Relationships between peak ground acceleration, peak ground velocity, and Modified Mercalli Intensity in California: Earthquake Spectra, the Professional Journal of the Earthquake Engineering Research Institute (EERI), Vol. 15, No. 3, pp. 557-564. Walls, C., Rockwell, T., Mueller, K., Bock, Y., Williams, S., Pfanner, J., and Fang, P., 1998, Escape tectonics in the Los Angeles metropolitan region and implications for seismic risk: Nature, Vol. 394, pp. 356-360. • Ward, S.N., and Valensise, G., 1994, The Palos Verdes terraces, California: Bathtub rings from a buried reverse fault: Journal of Geophysical Research Vol. 99, pp. 4485-4494. Earth Consultants International Seismic Hazards Page 2-95 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Wells, D.L. and Coppersmith, K., 1994, New empirical relationships among magnitude, rupture length, rupture width, rupture area, and surface displacement: Bulletin of the Seismological Society of America, Vol. 84, pp. 974-1002. Wesnousky, S.G., 1986, Earthquakes, Quaternary faults, and seismic hazard in California: Journal of Geophysical Research, Vol. 91, No. B12, pp. 12,587-12,631. Wolfe, M. R., Bolton, P. A., Heikkala, Greene M. M., May, P. 1., 1986, Land -Use Planning for Earthquake Hazard Mitigation: A Handbook for Planners: Natural Hazards Research and Applications Information Center, Special Publication 14, 122p. Wood, H.O., 1916, California earthquakes —A synthetic study of recorded shocks: Bulletin of the Seismological Society of America, Vol. 6, No. 2. Wood, H.O., 1933, Preliminary Report on the Long Beach earthquake of March 10, 1933: Bulletin of the Seismological Society of America, Vol. 23, No. 2, pp. 43-56. Woodward -Clyde Consultants, 1979, Report of the evaluation of maximum earthquake and site ground motion parameters associated with the offshore zone of deformation, San Onofre Nuclear Generation Station: Santa Ana, California, unpublished consulting report prepared for Southern California Edison, WCC Project No. 41101. • Working Group on California Earthquake Probabilities (SCEC), 1995, Seismic hazards in Southern California: Probable earthquakes, 1994 to 2024: Bulletin of the Seismological Society of America, Vol. 85, No. 2, pp. 379-493. Wright, T.L., 1991, Structural geology and tectonic evolution of the Los Angeles basin, California; in Biddle, K. (editor), Active Margin Basins, American Association of Petroleum Geologists Memoir 52, pp. 35-134. Youd, T.L., Hansen, C.M., and Bartlett, S.F., 1999, Revised MLR Equations for Predicting Lateral Spread Displacement; in O'Rurke, Thomas D., Bardet, 1.P., and Hamada, M., (editors), Proceedings of the Seventh U.S. — Japan Workshop on Earthquake Resistant Design of Lifeline Facilities and Countermeasures Against Soil Liquefaction: Multidisciplinary Center for Earthquake Engineering Research, SUNY, Buffalo, MCEER Report 99-0019, pp. 99-114. Youd, T. L., 1978, Major cause of earthquake damage is ground failure: Civil Engineering, Vol. 48, No. 4, pp. 47-51. Youd, T.L., and Perkins, D.M., 1978, Mapping liquefaction -induced ground failure potential: Proceedings of the American Society of Civil Engineers, Journal of the Geotechnical Engineering Division, Vol. 104, No. GT4, pp. 433-446. Youd, L. T., 1986, Geologic effects -liquefaction and associated ground failure: Proceedings of the 1986 Annual Conference Western Seismic Policy Council, pp. 8-30. Earth Consultants International Seismic Hazards Page 2-96 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Youd, T. L., and Keefer, D. K., 1981, Earthquake -induced ground failures; in Hays, W. W., (editor), Facing Geologic and Hydrologic Hazards: U. S. Geologic Survey Professional Paper 1240-13, pp.23-31. n U • Youd, T.L., Idriss, I.M. Andrus, R.D. Arango, I., Castro, G., Christian, J.T., Dobry, R., Liam Finn, W.D.L., Harder, L.F., Jr., Hynes, M.E., Ishihara, K., Koester, J.P., Liao, S.S.C., Marcuson, W.F., III, Martin, G.R., Mitchell, 1.K., Moriwaki, Y., Power, M.S., Robertson, P.K., Seed, R.B., Stokoe, K.H., II, 2001, Liquefaction resistance of soils: Summary Report from the 1996 NCEER and 1998 NCEER/NSF Workshops on Evaluation of Liquefaction Resistance of Soils: ASCE Journal of Geotechnical and Geoenvironmental Engineering, Vol. 127, No. 10, pp. 817-833 Ziony, J.I., and Yerkes, R.F., 1985, Evaluating earthquake and surface -faulting potential; in Ziony, J.I. (editor), Evaluating Earthquake Hazards in the Los Angeles Region — An Earth -Science Perspective: U.S Geological Survey Professional Paper 1360, pp. 33-91. Earth Consultants International Seismic Hazards Page 2-97 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • CHAPTER 3: GEOLOGIC HAZARDS 3.1 Physiographic Setting The City of Newport Beach and its Sphere of Influence are located in an area of widely diverse terrain at the southern margin of the Los Angeles Basin. The City is bounded on the northwest by the broad, nearly flat -lying coastal plain of Orange County - the great outwash plain of the Santa Ana River. To the northeast lie the foothills of the Santa Ana Mountains and the smaller Tustin Plain. Rugged coastal mountains are present to the south. The City's landscape can best be described by geographic area, each reflective of its distinct topographic features (see Figure 3-1). The central and northwestern portions of the City are situated on a broad mesa that extends southeastward to join the San Joaquin Hills. Commonly known as Newport Mesa, this upland has been deeply dissected by stream erosion, resulting in moderate to steep bluffs along the Upper Newport Bay estuary, one of the most striking and biologically diverse natural features in Orange County. The nearly flat-topped mesa rises from about 50 to 75 feet above mean sea level at the northern end of the estuary in the Santa Ana Heights area, to about 100 feet above sea level in the Newport Heights, Westcliff, and Eastbluff areas. Along the southwestern margin of the City, sediments flowing from the two major drainage courses that transect the mesa have formed the beaches, sandbars, and mudflats of Newport Bay and West Newport. These lowland areas were significantly modified during the last century in order to deepen channels for navigation and form habitable islands. Balboa Peninsula, a barrier beach that protects the bay, was once the site of extensive low sand dunes. In the southern part of . the City, the San Joaquin Hills rise abruptly from the sea, separated from the present shoreline by a relatively flat, narrow shelf. Originally formed by wave abrasion, this platform (also called a terrace) is now elevated well above the water and is bounded by steep bluffs along the shoreline. Balboa Peninsula and the harbor islands generally range from about 5 to 10 feet above sea level. The coastal platform occupied by Corona Del Mar ranges from about 95 to 100 feet above sea level, and the San Joaquin Hills, site of the Newport Coast development area, rise to an elevation of 1,164 feet at Signal Peak. • The two major drainages that have contributed greatly to the development of the City's landforms are the Santa Ana River and San Diego Creek. At one time, the natural course of the Santa Ana River hugged the western side of Newport Mesa, carving steep bluffs and feeding sediment into Newport Bay. In an attempt to reduce flooding on the coastal plain, the river was confined to man-made levees and channels by the early 1920s. North of the City, numerous streams draining the foothills, including Peters Canyon Wash, Rattlesnake Wash, Hicks Canyon, Agua Chinon, and Serrano Creek, merged with San Diego Creek and collectively cut a wide channel through the mesa, later filling it with sediment (Upper Newport Bay and the harbor area). The collected drainages are now contained in the man-made San Diego Creek Channel, and directed into Upper Newport Bay near the intersection of Jamboree Road and University Drive. The Bay also receives water from the Santa Ana Delhi Channel near Irvine Avenue and Mesa Drive. Earth Consultants International Geologic Hazards Page 3-1 2003 0 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Upper Newpor Newport Har Figure 3-1: Aerial View of Newport Beach, Showing Some of the Physiographic Features Discussed in the Text Darluin Hills ted) The portion of the San Joaquin Hills that lies within the City is drained by several deep canyons, including Buck Gully, Los Trancos Canyon, and Muddy Canyon, as well as numerous smaller, unnamed canyons. Carrying significant amounts of water only during the winter, these streams • flow directly to the Pacific Ocean. Drainage courses on the north side of the hills, including Bonita and Coyote Creeks, are tributaries of San Diego Creek. Development in the City began in the late 1800's with the arrival of the railroads and the McFadden (Newport) Pier. Development gradually spread outward from the rail lines and beaches, eventually covering most of Newport Mesa and the low hills to the south. More recently, residential developments and a major transportation corridor (State Route 73) have made significant advances into the rugged terrain of the San Joaquin Hills, and future hillside communities are in the planning and development stages. These types of projects require major earthwork activities, typically involving the movement of millions of cubic yards of earth. Because the severity of geologic hazards increases in the hills, corrective grading often accounts for a significant portion of the overall yardage. 3.2 Geologic Setting The physical features described in the previous section are a reflection of the geologic and climatic processes that have played upon this region the last few million years. The City of Newport Beach lies at the northern end of the Peninsular Ranges, a geologic/geomorphic province characterized by a northwest -Vending structural grain aligned with the San Andreas fault, and represented by a series of northwest -trending faults, mountain ranges and valleys stretching from Orange County to the Mexican border. Displacements on faults in this region are mainly of the strike -slip type, and where they have been most recently active, they have deformed the landscape and altered drainage patterns. An example of such faulting in the Newport Beach area is the Newport - Earth Consultants International Geologic Hazards Page 3-2 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Inglewood fault zone, which trends northwest across the Los Angeles Basin, leaving the coastline at the northwestern corner of the City, and continuing to the south offshore. Predominantly right - lateral in movement, the Newport -Inglewood fault is responsible for uplifting the chain of low hills and mesas that extends from Beverly Hills to Newport Beach across the relatively flat coastal plain. The location and structure of the fault zone is known primarily from a compilation of surface mapping and deep, subsurface data, driven initially by an interest in oil exploration (all of the hills and mesas, including Newport Mesa, have yielded petroleum), and later by a shift toward evaluating earthquake hazards. The fault is an active structure and was the source of the 1933 M6.4 Long Beach earthquake. Despite the name, this earthquake was actually centered closer to Newport Beach, near the mouth of the Santa Ana River (Hauksson and Gross, 1991). The San Joaquin Hills are the westernmost range in the Peninsular Ranges province. The hills are structurally complex, consisted of tilted fault blocks, and numerous north and northwest -trending Tertiary- and Quaternary -age faults. Within the hills, the major structural feature is the Pelican Hill fault zone, which trends northwesterly from Emerald Bay to the Big Canyon area. The fault zone is several hundred feet wide, and has left the adjacent bedrock in a highly sheared, folded, and fractured condition (Munro, 1992; Barrie et al., 1992). The Pelican Hill fault, as well as the other faults exposed in the hills, has largely been determined to be inactive during Holocene time (Clark et al., 1986). In recent years, scientists have discovered that the northern end of the province, primarily the Los Angeles metropolitan area, is underlain by a series of deep-seated, low -angle thrust faults. When these faults do not reach the surface, they are called "blind thrusts". Faults of this type are thought • to be responsible for the uplift of many of the low hills in the Los Angeles Basin, such as the Repetto or Montebello Hills. Previously undetected blind thrust faults were responsible for the M5.9 Whittier Narrows earthquake in 1987, and the destructive M6.7 Northridge earthquake in 1994. It has long been recognized that the San Joaquin Hills are part of a northwest -trending anticline (a convex fold) that extends from San Juan Capistrano to the Huntington Mesa (Vedder, 1957 and 1975). Recent research suggests that the anticline, which includes the Newport and Huntington Mesas as well as the San Joaquin Hills, is part of a structure that is being uplifted by an active blind thrust fault that dips southward beneath the area (Grant et al., 1999). The growth of the San Joaquin Hills has been recorded in remnants of marine terraces of various ages that cap the northern and western slopes. These terraces consist of wave -eroded, sediment -covered platforms (similar to the one present at the base of the hills today) that have been uplifted as the hills rose above sea level. Based on measurements of terrace elevations and dating of the sediments, uplift of the hills started approximately 1.2 million years ago, and has continued through the Holocene at a rate of about 0.25 meters per 1,000 years (Barrie et al., 1992; Grant, 1999). Recognition of the San Joaquin Hills thrust fault extends the area of active blind thrusts and associated folding southward from Los Angeles into the Newport Beach area (Grant et al., 1999). 3.3 Geologic Units Alluvial sediments of late Holocene age are present in active and recently active stream channels . throughout the City, in addition to beach, marshland, and intertidal deposits of Newport Harbor and Upper Newport Bay. Newport Mesa is underlain primarily by shallow marine sediments Earth Consultants International Geologic Hazards Page 3-3 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . ranging in age from early to late Pleistocene. East of Upper Newport Bay, these deposits are capped with a thin veneer of late Pleistocene to early Holocene alluvial fan sediments shed from the San Joaquin Hills. Where streams have deeply incised the mesa, Tertiary -age sedimentary bedrock, also of marine origin, is exposed beneath the younger deposits. Similar bedrock formations underlie the San Joaquin Hills. The general distribution of geologic units that are exposed at the surface are shown on the Geologic Map (Plates 3-1 a and 3-1 b). In the section that follows, the characteristics of each unit are discussed using nomenclature published by Morton and Miller (1981) and Morton (1999). Descriptions of the units, including some of their engineering characteristics, have been compiled from various sources including published regional geologic reports and papers, as well as unpublished consulting reports. The distribution of geologic units with respect to their general engineering characteristics is illustrated on Plate 3.2. The units are described in the next section, from youngest to oldest. There are many deposits of man-made fill throughout the City, including most notably, the harbor islands, road and bridge embankments, and canyon fills associated with mass -graded hillside developments. These deposits vary widely in size, age, and composition, and although some are significantly large and thick, due to the map scale they are not shown on the Geologic Map. 3.3.1 Young Surficial Deposits Holocene deposits within the City generally occupy the low-lying areas, including beaches, estuaries, and canyon -bottoms. Being geologically young and subject to active • geologic processes, these deposits are typically unconsolidated and have very little, if any, soil development. 3.3.1.1 Beach Sediments (map symbol: Qm) Late Holocene beach sand forms a narrow strandline along the outer portion of Balboa Peninsula, continuing northward along West Newport to the northern edge of the City. Beach deposits are also present below the Corona Del Mar bluffs and in Crystal Cove State Park. These sediments generally consist of light gray to tan, fine- to coarse -grained sand with infrequent gravel lenses. Near sea cliffs they are often pebbly and cobbly. Beach deposits typically slope gently towards the ocean. Due to the lack of cohesion and vegetation, beach sands are highly vulnerable to erosion and have poor slope stability characteristics. Permeability is high, and the expansion potential is low. 3.3.1.2 Dune Sediments (map symbol: Qe) Behind the gently sloping tidal zone, Late Holocene aeolian (wind-blown) sands are present from West Newport to the tip of the Balboa Peninsula. Most of these deposits are now covered by development; however, a few low dunes still remain locally. These sediments are similar in composition and engineering characteristics to beach sands. Dunes often are covered with a sparse growth of iceplant, grasses, and low shrubs, which serve to stabilize the sand. 3.3.1.3 Estuarine Sediments (map symbol• Qes) Late Holocene deposits within Upper Newport Bay consist of sand, silt, and clay that inter - finger with coarser stream -laid deposits at the mouths of San Diego Creek, Big Canyon, and several smaller channels that drain into the Bay. Estuarine deposits in the present-day Earth Consultants International Geologic Hazards Page 3-4 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • tidal flats of Upper Newport Bay are typically saturated and have a high organic content. Prior to development, the area occupied by Newport Harbor and its various islands consisted of intertidal mudflats and sandbars similar to Upper Newport Bay (see Figure 3- 2). From an engineering perspective, most estuarine deposits are highly unstable, being subject to settlement, erosion, and poor slope stability. Depending on the clay content, they may also be expansive. • Figure 3-2: Estuarine Setting of Upper Newport Bay 3.3.1.4 Young Alluvial Fan and Fluvial Channel Sediments (map symbol. Wand Qya) Holocene to latest Pleistocene in age, alluvial fan and fluvial (stream laid) deposits consisting of mixed sand, silt, clay, and gravel, are found lining active or recently active stream channels along the western edge of Newport Mesa, and within larger canyons draining the San Joaquin Hills. These deposits merge with coastal dune deposits west of the mesa, and mix with submerged estuarine deposits at the head of Upper Newport Bay. Such deposits are typically of low density, and contain organic debris. Consequently, they are subject to settlement under loading (with fill embankments or buildings), erosion, and poor slope stability. Peat layers are present near the coast. Due to the variation in grain size, the expansion characteristics can range from low to high. 3.3.1.5 Landslides (map symbol: Qy1s) The San Joaquin Hills contain numerous landslides or suspected landslides composed of highly fragmented, jumbled bedrock debris as well as largely coherent bedrock blocks. Landslides are typically identified by their distinctive morphology, which most often includes a steep, arcuate headscarp, undulating or relatively flat-topped head, and a blocked or diverted drainage at the toe. • Earth Consultants International Geologic Hazards Page 3-5 2003 • • ,•. ° `+-I ,Ir '(rya I To 'Qya Qyf : ��, •. Qomf I' Tcs Ze P(\ Qom <`s, �•./� Tcs ,h+` xt�h '•� Tm Qes yQomf O� , Qm Qe \\ NOTES: This map is intended for general land use planning only. Information on this map is not sufficient to serve as a substitute for detailed geologic investigations of individual silos, nor does it sallsty the evaluation requirements set forth In geologic hazard regulations. Earth Consultants International (ECI) makes no moresentalions or warranties regarding the accuracy of the data from vMlch these maps were derived. ECI shall not be liable under any circumstances for any direct, indirect, special, incidental, or consequential damages vdth respect to any claim by any user or third party on account of, of arising from, the use of this map. 1 Td Geologic Map Newport Beach, California EXPLANATION SYMBOLS Fault: solid where location known, i dashed where approximate, dotted where concealed. Geologic Contact Newport Beach City Boundary _ �\! T0t \ � i' ���� Sphere of Influence \\Qy°m1 for the description of geologic units, refer to ° • \\� Tib�1 r I \ Plate 3-1b \� �t I I Scale: 1:60,000 Tm ; tl 0.5 0 0.5 1 L5 Tsob Mil 1 0 1 2 3 Tv Qomf \'\ I O� \ \ Qyls. Tcs A 11 Kilometers Base Map: USGS Topographic Map from Sure!MAPS RASTER Source: Morton et al., 1976 and Morton, 1999 —a a 3 — Earth Consultants = , Intemational = ` Project Number: 2112 w^' Date: July. 2003 Plate 3-la • • GEOLOGIC UNIT DESCRIPTIONS Young Surficial Deposits om Marine sediments (late Holocene) - Unconsolidated, active or recently active beach sand deposits. Eollan sediments (late Holocene) - Unconsolidated, active a recently active sand dune deposits. uP6 Estuarine sediments (late Holocene) - Unconsolidated, active, or recently active, sandy, silty, and clayey organic. rich intertidal deposits. Young fluvial channel sediments (Holocene and latest Pleistocene) - Unconsolidated sand, slit, clay, and gravel In �. active or recently active stream channels. M ` ,,, Young alluvial tan sediments (Holocene and latest Pleistocene) - Unconsolidated sand, silt, and clay. N C%7 Landslide (Holocene and latest Pleistocene) -Highly fragmented and broken to largely coherent bedrock blocks. _ F- Older Surficial Deposits i—a Old marine sediments (late to middle Pleistocene) - Light gray to brownish gray silty sand and fine-grained sand locally jwith gravel and shell fragments. East of Newport Bay, covered with veneer of younger alluvial fan sediments (Qomf). Very old marine sediments (middle to early Pleistocene) - Light gray to yellow fine- to medium -grained sand, locally clay - rich and reddish In color; gravelly near the base. Very old channel sediments (middle to early Pleistocene) - Reddish brown to yellowish brown gravel, sand. silt and clay, typically poorly bedded, locally with cross -bedded lenses of sand and gravel; locally cemented. Tertiary Sedimentary Rocks - Th Niguel Formation (Pliocene) - Light gray to grayish yellow sandstone interbedded with greenish siltstone and yellowish brown to pale reddish brown conglomerate and breccia. Tn Capistrano Formation Siltstone Facies (late Miocene) - Yellowish to brownish gray concretionary siltstone and mudstone with lenses of whitish gray sandstone; sparse diatomaceous and tuffaceous beds, Monterey Formatlon (middle to late Miocene) - White to yellowish gray siliceous and diatomaceous siltstone, shale, and clayey elltstone with interbedded fine-grained sandstone. Locally contains lenses and thin beds of water -laid tuff. San Onofre Breocia (middle Miocene) - Brown to yellowish brown breccia with interbedded conglomerate, sandstone, siltstone, and mudstone. Topange Formation (middle Mlocene) - Marine sandstone, siltstone, and shale. Pauladno Member - Pale gray, tuffaceous siistone and sandstone with Interbedded breccia. Contains andesite 1 flows locally sandstones and breccia contain abundant endears fragments. Los Trancos Member - Pale gray, brownish gray and olive -gray, siltstone and clayey siltstone with Interbedded shale and medium- to coarse -grained sandstone. Bommer Member - Yellowish brown to brownish gray, medium- to coarse -grained sandstone and silty sandstone. Minor siltstone and conglomerate. _ Vaqueros Formation (early Miocene) - Yellowish brawn fine-grained sandstone with interbedded sihstone, shale, mudstone, and minor conglomerate. Intrusive Igneous Rocks T� ( Andesitic intrusive rocks (middle Miocene) - Dark gray to olive gray intrusive rock primarily of andesitic composition. I = Debase intrusive rocks (middle Miocene) - Diabasic teMured shallow intrusive rocks. Earth - nternaConsultants\ Explanation for Geologic Map Pate International > Project Number: 2112 3 — 1 b Date: July, 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Most of the slides appear to be rotational failures, occurring in steep natural slopes composed of bedrock weakened by the intense fracturing, shearing and folding in or near the Pelican Hill fault zone. Some of the slides may be block glides associated with the failure of unsupported weak bedding planes. The larger slides are probably more than a hundred feet thick. • Landslide materials are commonly porous and very weathered in the upper portions and along the margins. They may also have open fractures and joints. The head of the slide may have a graben (pull -apart area) that has been filled with soil, bedrock blocks and fragments. Some of these slides have been reactivated in the late Holocene and pose a significant hazard to development. Landslides are further discussed in the geologic hazards section (Section 3.4) below. 3.3.2 Older Surficial Deposits Pleistocene marine deposits of various ages are preserved on the surface of Newport Mesa and on older marine terraces notched into the north and west flanks of the San Joaquin Hills. These deposits are deeply dissected, moderately consolidated, and have well - developed soil profiles. 3.3.2.1 Old Marine Sediments (map symbol. Qom and QomO A large portion of the City, including the uplifted Newport Mesa and coastal platforms, are capped by brownish gray to light gray silty sand and fine-grained sand, locally with scattered gravel and lenses of coarse sand, gravel and shell fragments (Qom) (see Figure 3- 3). Bedding ranges from massive to well developed, with cross -bedding. These sediments have moderate to high density, and are friable, similar to beach sand, below the soil horizon. A strongly developed argillic soil profile is present, and is locally more than 10 feet thick (see Figure 3-4). Except for the soil zone, permeability is high and the expansion potential is low. Due to a lack of cohesion, the erosion potential is high. The soil zone contains a higher clay content, resulting in lower permeability and erodibility, but with a higher potential for expansion. East of Newport Bay, the old marine deposits are covered with a veneer of younger alluvial fan sediments shed from the San Joaquin Hills (Qomf). 3.3.2.2 Very Old Marine Sediments (map symbol. Qvom) This unit includes sediments of variable thickness deposited on prehistoric wave -eroded platforms. These deposits are now present as erosional remnants perched at higher elevations within the San Joaquin Hills. Several terrace platforms that increase in age with increasing elevation have been identified in the San Joaquin Hills (see Figure 3-5). The terrace deposits typically consist of light gray to yellow, silty fine- to medium -grained sand; they are locally clay -rich and reddish to orange -brown in color. Lenses and beds of gravel are commonly present in the lower section of the deposit, with concentrations of cobbles, pebbles and shell fragments at the base. These sediments are moderately well cemented and slightly to moderately jointed. The engineering characteristics of this unit are similar to those of the old marine sediments. Earth Consultants International 2003 Geologic Hazards Page 3-8 • • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Figure 3-3: View to the Northwest of Newport Mesa (left -center), and Newport Bay (foreground) Figure 3-4: Older Marine Terrace Sediments Exposed in Grading Cut Notice reddish, clay -rich, well -developed soil profile at the top. rr rr Argillic soil horizon 1) Older Marine + Terrace Deposits • Earth Consultants International Geologic Hazards Page 3-9 2003 Cl is HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Figure 3-5: Detail Showing Older Marine Terraces Present at Various Elevations Within and Near the San Joaquin Hills (from Grant et al., 1999) r ifs `�1jC It ti / • ` IIc j 3•{y 3.3.2.3 Very Old fluvial Channel Sediments (map symbol. Qvoa) These sediments consist of gravel, sand, silt, and clay that are now present in elevated bench -like terraces flanking the modern stream channels. Within the Newport Beach area, older river terraces are present along Bonita Creek, on the northern side of the San Joaquin Hills. Typically reddish brown to yellowish brown and grayish brown, these deposits are poorly bedded, but locally have lenses of cross -bedded sand and gravel. Induration ranges from poor to well developed; the unit is locally cemented. Permeability and expansion potential are highly variable, depending on the composition and degree of soil development. Slope stability is generally good, with most slope failures consisting of slumping along the walls of active stream channels. Susceptibility to erosion is low in natural slopes with gentle gradients, and moderately high in steeper, graded slopes. 3.3.3 Tertiary Sedimentary Rocks Within the City, areas of high relief are underlain primarily by a complex assemblage of sedimentary rocks created by multiple episodes of faulting and folding. All of these rocks are marine in origin, having formed from sediments deposited in a deep ocean embayment that encroached into the Orange County area prior to uplift of the region. • Earth Consultants International Geologic Hazards Page 3-10 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Figure 3-6: View of Newport Mesa showing the Older Marine Terrace Deposits (coincident with the vegetation at the top of the bluffs) Capping Deposits of the Capistrano Formation (in the lower two-thirds of the bluffs) Terrace Deposits Capistrano Formation • 3.3.3.1 Niguel Formation (map symbol. Tn) The Pliocene -age Niguel Formation is found only in the Eastbluff and Bonita Canyon areas, where stream erosion has cut down through the mesa to expose the bedrock underlying the old marine terrace deposits. This rock unit consists of light gray to grayish yellow sandstone, interbedded with greenish siltstone and yellowish brown to pale reddish brown conglomerate and breccia. Bedding is well developed in the sandstone, but is poor to massive in the conglomerate and siltstone sections. Sandstone beds are typically friable, whereas the conglomerate and breccia units are moderately indurated. Jointing is rare. Permeability ranges from low to high, and due to the mostly granular nature of the deposit, erodibility is also high. Slope stability is generally good, except for surficial slumping on bluffs during periods of heavy rainfall. The expansion potential is low except in clay -rich beds, which can be very highly expansive. 3.3.3.2 Capistrano Formation - Si$stone Facies (map symbol: Tcs) The late Miocene to early Pliocene Capistrano Formation is exposed in bluffs along the western side of Upper Newport Bay, in the Westcliff area. This unit consists of massive to crudely bedded, yellowish gray to medium brownish gray concretionary siltstone and mudstone with lenses of whitish gray sandstone. Well -bedded diatomaceous and tuffaceous beds are present locally. This rock is highly jointed, and contains common low angle shears. Gypsum is frequently found filling joints and shear planes. Permeability of the rock is low, and the expansion potential is high to very high. Although resistant to erosion, slope stability is generally poor. • Earth Consultants International Geologic Hazards Page 3-11 2003 • • • NOTES: This map is irdended for general land use planning only. Information an this map Is not sufficient to serve as a substitute for detailed geologic investigations of individual so", nor does it satisfy the evaluation requirements set forth In geologic hazaM regulations. Earth Consultants International (ECI) makes no representations or warranties regarding The accuracy of the data from which these maps were derived. ECI shall not be liable under any circumstances for any direct, Indllski special, Incidental, or consequential damages with respect to any claim by any user or third party on account of, or arising from, the use of this map. d N r 01m UNIT DESCRIPTIONS Dill ra Meitle•Urconsk. Engineering bw line- to cmrse sand d low sane at low density; locally carters density, Mvariable amhe scial slh, gravel, and in carry, oftoms locallyincanymbotmms mtMaVidahl zone andclay Materials Map Uncomaldehig clay, andsable sand of few is U and high organic contenS typically density Saturated Naaabd Said ands try sand with minor gravel and cobbles, moderate m high deni massive m cmn-tsd0ec wftMn Iitablebemw taesnot aone. wine the San Joaquin Hcemented only . Newport Beach, CaliforniaHills,bcny' -Landehds materials d variable di nelty Fractured m broken bedrock, locallyornad with wib, typically wnteln water perched above the rupture rove Irabwk hmgnined sedimentary rocks of moderate ■Chiefly to high density bedding ranges from missive to lambrlil a d fellyto imm�seak, pl lurM ahnnti and bltled; conbin weak, plasm .clay EXPLANATION bads; bodily cenesed and hard. coaru-gained sad mentary hi rocks of h ❑Chisfy density, bedding marsI. m crudi d". W; forkound and sh rI rmer rourb; commonly wry handand camsmad. Clargo. roks ofhigh dehy mmassive commonly fraomnd and loused; locally highly altered and \` dacompasad; hard and very rauates where un- .` Newport Beach City Boundary weathered. Sphere of Influence ♦;1 `W�:' Scale: 1:60,000 A w Miles 1 0 1 2 3 1� r Kilometers Base Map: USGS Topographic Map from Sure!MAPS RASTER ¢ Source: Based on data from Morton et al., 1976 and r.' Morton, 1999 Earth Y Consultants A,_ Intemational , Project Number: 2112 v,raH Date: July, 2003 Plate 3-2 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 3.3.3.3 Monterey Formation (map symbol: Tm) The Monterey Formation is widely exposed in the San Joaquin Hills south of the Pelican Hill fault zone. It also underlies the Pleistocene marine deposits that cap the mesa and coastal platform, and is therefore exposed in many of the bluffs and canyon sidewalis where stream dissection has been deep. This rock unit consists predominantly of thinly bedded to laminated siliceous siltstone, shale, and clayey siltstone with interbeds of clayey, diatomaceous siltstone and very fine-grained sandstone. Locally it contains irregular lenses and thin beds of water -laid tuff (volcanic ash) that is frequently altered to highly plastic clay. Rock of the Monterey Formation is moderately to intensely fractured, particularly near the Pelican Hill fault. Cemented sandstones and siliceous shales are very hard, and can be difficult to excavate. Due to the fine-grained nature of the sediments, permeability is low, and resistance to erosion is generally good. Highly expansive clays are common, and slope stability is poor, as indicated by the numerous bedrock landslides within this unit, and the many surficial failures that occur on natural slopes during winters of heavy rainfall. 3.3.3.4 San Onofre Breccia (map symbol: Tsob) The middle Miocene San Onofre Breccia is present in the San Joaquin Hills as a narrow, fault -bounded block within the Pelican Hill fault zone. This rock unit consists of brown to yellowish brown breccia (coarse -grained rock composed of angular broken rock fragments held together by a mineral cement or matrix) with interbedded conglomerate, sandstone, • siltstone, and mudstone. Bedding structure is poor, especially in this area, due to shearing associated with the fault zone. This rock unit is commonly well indurated and cemented, making it difficult to excavate. Permeability is low, and expansion characteristics are generally low, except in clayey zones that can be highly expansive. Slope stability in this unit in normally good, but fracturing and shearing within the fault zone have weakened the rock fabric, and numerous slope failures are present as bedrock landslides, rockfalls, and surficial slumping on steep natural slopes. 3.3.3.5 Topanga Formation (map symbol. Tt, TIP, Tit, Ttb) The Paularino member of the middle Miocene Topanga Formation (Ttp) has very limited exposure in canyon sidewalls in the Bonita Creek area, where it is capped by older marine deposits and younger fan sediments. This unit consists of pale gray tuffaceous (ash rich) siltstone and sandstone with interbedded breccia. Andesite flows are present locally, and the sandstones and breccias contain abundant andesite fragments. Bedding is generally massive except in the fine-grained fraction, which is thin -bedded. The rock is typically well indurated and cemented, resulting in low permeability and moderate to difficult excavation. Slope stability and resistance to erosion are moderately good. Expansion potential, for the most part, is in the low range. North of the Pelican Hill fault zone, the hills are underlain predominantly by the Los Trancos and Bommer members of the Topanga Formation. The Los Trancos member (Ttlt) consists of light gray, brownish gray, and olive -gray siltstone and clayey siltstone with interbedded claystone and grayish brown sandstone. Bedding is typically well developed • as thinly bedded to laminated strata, although intervals of thick to massive bedding occur. Permeability is low, and susceptibility to erosion ranges from low to high. Expansion Earth Consultants International Geologic Hazards Page 3-13 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • characteristics are in the moderately high to high range. Slope stability is poor, as indicated by many bedrock and surficial failures, especially near the Pelican Hill fault zone. The Bommer member (Ttb) consists of massive to thickly bedded, medium- to coarse - grained sandstone and silty sandstone, with a minor amount of interbedded conglomerate and siltstone. The color ranges from yellowish -brown to grayish -brown with orange iron - oxidation staining. The upper contact with the Los Trancos member is gradational. Rocks of the Bommer member are very dense and commonly cemented, making excavation difficult. Permeability and erodibility in this unit are moderately low. Expansion potential is low in the sandstone intervals, and moderate to high in the less frequent siltstone intervals. Slope stability is generally good except where faulting has weakened the rock fabric, resulting in numerous landslides. 3.3.3.6 Vaqueros formation (map symbol: TV) The early Miocene Vaqueros Formation is present as a large, fault -bounded block in the southern part of the hills. Consisting of pale yellowish brown siltstone, fine-grained sandstone, mudstone, and shale, this unit is typically massive to thick bedded, with minor thin -bedded intervals of siltstone and shale. Permeability is moderately poor, and silty intervals are moderately expansive. Susceptibility to erosion ranges from low to high. Slope stability is very poor in this area, due to deformation from faulting, as indicated by large bedrock landslides that involve a significant portion of the rock exposed. . 3.3.4 Tertiary Intrusive Rocks 3.3.4.1 Andesite and Diabase (map symbol. Ta and Td) Middle Miocene andesite and diabase (rock of igneous origin) occur as dikes along faults or shear zones, and locally as irregular -shaped bodies, commonly near faults. These rocks typically form by intrusion of magma into fractures, joints and faults within the surrounding rock. Unweathered portions of these rocks are dense and very resistant to erosion, forming rocky ribs along faults and ridgelines. The color ranges from dark gray to olive gray in fresh rock, to light brownish gray, light brown, yellowish brown and yellowish orange if altered and decomposed. Fracturing and jointing are common. Permeability is moderate to low, and expansion characteristics are generally low. Unweathered rock may be very difficult to excavate. Slope stability is typically good. Rockfalls may pose a problem locally where hard, fractured outcrops are present. 3.4 Geologic Hazards in the Newport Beach Area Geologic hazards are generally defined as surficial earth processes that have the potential to cause loss or harm to the community or the environment. The basic elements involved in the assessment of geologic hazards are climate, geology, soils, topography, and land use. 3.4.1 Landslides and Slope Instability In Newport Beach, landslides have been and remain a significant risk, as development reaches higher elevations within the hills. Although an active landslide tends to affect a • relatively small area (as compared to a damaging earthquake), and is generally a problem for only a short period of time, the dollar loss can be high. Insurance policies typically do Earth Consultants International Geologic Hazards Page 3-14 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • not cover landslide damage, and this can add to the anguish of the affected property owners. Careful land management in hillside areas can reduce the risk of economic and social losses from slope failures. This generally includes land use zoning to restrict development in unstable areas, grading codes for earthwork construction, geologic and soil engineering investigation and review, construction of drainage structures, and where warranted, placement of warning systems. Other important factors are risk assessments (including susceptibility maps), a concerned local government, and an educated public. 3.4.1.1 Types of Slope Failures Slope failures occur in a variety of forms, and there is usually a distinction made between gross failures (sometimes also referred to as "global" failures) and surficial failures. Gross failures include deep-seated or relatively thick slide masses, such as landslides, whereas surficial failures can range from minor soil slips to destructive debris flows. Slope failures can occur on natural or man-made slopes. For man-made slopes, most failures occur on older slopes, many of which were built at slope gradients steeper than those allowed by today's grading codes. Although infrequent, failures can also occur on newer graded slopes, generally due to poor engineering or poor construction. Slope failures often occur as elements of interrelated natural hazards in which one event triggers a secondary event, such earthquake -induced landsliding, fire -flood sequences, or storm -induced mudflows. • Gross Instability . Landslides - Landslides are movements of relatively large land masses, either as a nearly intact bedrock blocks, or as jumbled mixes of bedrock blocks, fragments, debris, and soils. The type of movement is generally described as translational (slippage on a relatively planar, dipping layer), rotational (circular -shaped failure plane) or wedge (movement of a wedge-shaped block from between intersecting planes of weakness, such as fractures, faults and bedding). The potential for slope failure is dependent on many factors and their interrelationships. Some of the most important factors include slope height, slope steepness, shear strength and orientation of weak layers in the underlying geologic unit, as well as pore water pressures. joints and shears, which weaken the rock fabric, allow penetration of water leading to deeper weathering of the rock along with increasing the pore pressures, increasing the plasticity of weak clays, and increasing the weight of the landmass. For engineering of earth materials, these factors are combined in calculations to determine if a slope meets a minimum safety standard. The generally accepted standard is a factor of safety of 1.5 or greater (where 1.0 is equilibrium, and less than 1.0 is failure). Natural slopes, graded slopes, or graded/natural slope combinations must meet these minimum engineering standards where they impact planned homes, subdivisions, or other types of developments. Slopes adjacent to areas where the risk of economic losses from landsliding is small, such as parks and roadways, are often allowed, at the discretion of the local reviewing agency, a lesser safety factor. From an engineering perspective, landslides are generally unstable (may be subject to reactivation), and may be compressible, especially around the margins, which are typically highly disturbed and broken. The headscarp area above the landslide mass is also • unstable, since it is typically oversteepened, cracked, and subject to additional failures. Earth Consultants International Geologic Hazards Page 3-15 2003 C • r l _ e p S _ � • _t. t J O A 1 ' / �\ [J+. ^I 17 � _"�' ♦ - -E Y gyp. � �` 1 , '\ NOTES: This map is intended for general land use planning only. Information an this map Is not sufficient to servo as a substitute for detailed geologic investigations of Individual sites, nor does It satisfy the evaluation requirements set forth In geologic hazard regulations. Earth Consultants Imernational (ECp makes no representations or warranties regarding the accuracy of the data from which these maps were derived. ECI shall not be liable under any circumstances for any direct. Indirect, special. Incidental, or consequential damages with respect to any claim by any user or third pony on account of, or arising from, the use of this map. .A li -4 A-.� �` Slope Distribution Map Newport Beach, California EXPLANATION Slope (in degrees) 0 to 10 10 to 26 26 to 40 40 and greater Newport Beach City Boundary Sphere of Influence Scale: 1:60,000 0.3 0 0.5 1 1.5 Miles 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from Sure!MAPS RASTER Source: Derived from USGS 10-m Digital Elevation Model s ,. Earth a ntConsultants Internatioatjonal Project Number: 2112 Date: July, 2003 Plate 3-3 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Surficial instability Slope Creep - Slope creep in general involves deformation and movement of the outer soil or rock materials in the face of the slope, due to the forces of gravity overcoming the shear strength of the material. Soil creep is the imperceptibly slow and relatively continuous downslope movement of the soil layer on moderate to steep slopes. Creep occurs most often in soils that develop on fine-grained bedrock units. Rock creep is a similar process, and involves permanent deformation of the outer few feet of the rock face resulting in folding and fracturing. Rock creep is most common in highly fractured, fine-grained rock units, such as siltstone, claystone and shale. Creep also occurs in graded fill slopes. This is thought to be related to the alternate wetting and drying of slopes constructed with fine-grained, expansive soils. The repeated expansion and contraction of the soils at the slope face leads to loosening and fracturing of the soils, thereby leaving the soils susceptible to creep. While soil creep is not catastrophic, it can cause damage to structures and improvements located at the tops of slopes. Soil Slip - This type of failure is generated by strong winter storms, and is widespread in the steeper slope areas, particularly after winters with prolonged and/or heavy rainfall. Failure occurs on canyon sideslopes, and in soils that have accumulated in swales, gullies and ravines. Slope steepness has a strong influence on the development of soil slips, with most slips occurring on slopes with gradients of between about 27 and 56 degrees (Campbell, • 1975). For the slope gradients in Newport Beach refer to Plate 3-3. Earth Flow - This type of slope failure is a persistent, slow -moving, lobe -shaped slump that typically comes to rest on the slope not far below the failure point. Earth flows commonly form in fine-grained soils (clay, silt and fine sand), and are mobilized by an increase in pore water pressure caused by infiltration of water during and after winter rains. Earth flows occur on moderate to steep slopes, typically in the range of about 15 to 35 degrees (Keefer and Johnson, 1983). Debris Flow - This type of failure is the most dangerous and destructive of all types of slope failure. A debris flow (also called mudflow, mudslide, and debris avalanche) is a rapidly moving slurry of water, mud, rock, vegetation and debris. Larger debris flows are capable of moving trees, large boulders, and even cars. This type of failure is especially dangerous as it can move at speeds as fast as 40 feet per second, is capable of crushing buildings, and can strike with very little warning. As with soil slips, the development of debris flows is strongly tied to exceptional storm periods of prolonged rainfall. Failure occurs during an intense rainfall event, following saturation of the soil by previous rains. A debris flow most commonly originates as a soil slip in the rounded, soil -filled "hollow" at the head of a drainage swale or ravine (see Figure 3-7). The rigid soil mass is deformed into a viscous fluid that moves down the drainage, incorporating into the flow additional soil and vegetation scoured from the channel. Debris flows also occur on canyon walls, often in soil -filled swales that do not have topographic expression. The velocity of the flow • depends on the viscosity, slope gradient, height of the slope, roughness and gradient of the channel, and the baffling effects of vegetation. Even relatively small amounts of debris can Earth Consultants International Geologic Hazards Page 3-17 2003 11 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA cause damage from inundation and/or impact (Ellen and Fleming, 1987; Reneau and Dietrich, 1987). Recognition of this hazard led FEW to modify its National Flood Insurance Program to include inundation by "mudslides" (FEW, 2001). Watersheds that have been recently burned typically yield greater amounts of soil and debris than those that have not burned. Erosion rates during the first year after a fire are estimated to be 15 to 35 times greater than normal, and peak discharge rates range from 2 to 35 times higher. These rates drop abruptly in the second year, and return to normal after about 5 years (Tan, 1998). In addition, debris flows in burned areas are unusual in that they can occur in response to small storms and do not require a long period of antecedent rainfall. These kinds of flows are common in small gullies and ravines during the first rains after a burn, and can become catastrophic when a severe burn is followed by an intense storm season (Wells, 1987). Figure 3-7: Sketch of a Typical Debris Avalanche Scar and Track SCAR (Area of initial failure) i TRACK (May or may not be eroded) ZONE OF DEPOSITION (Fan) —�- BEDROCK SOIL OR COLLUVIUM From: httw//www.consr% 1 .,uv/cgs/information/publications/cgs notes/note 33/inclex.htm. Original sketch by Janet K. Smith Rockfalls — Rockfalls are free -falling to tumbling masses of bedrock that have broken off steep canyon walls or cliffs. The debris from repeated rockfalls typically collects at the base of extremely steep slopes in cone -shaped accumulations of angular rock fragments called talus. Rockfalls can happen wherever fractured rock slopes are oversteepened by stream erosion or man's activities. Most of the landslides in the San Joaquin Hills are pre -historic in age. The combination of low a sea level in Pleistocene time (when much of the Earth's water was trapped in great • Earth Consultants International Geologic Hazards Page 3-18 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • ice sheets) and regional tectonic uplift has resulted in the oversteepening of slopes facing small to large stream channels. This, along with the presence of weak bedrock materials, severe deformation associated with the numerous faults that traverse the hills, and a wetter prehistoric climate, have been the major factors contributing to the occurrence of the large number of landslides that cover the hills. All the bedrock formations in the San Joaquin Hills have been involved in landsliding, however the most susceptible formations are those that are largely composed of siltstone, claystone, mudstone, and shale, such as the Monterey, Topanga (Los Trancos member), and Vaqueros Formations (see Plate 3-1a). These units are present in the central, southern, and western portions of the hills. The San Onofre Formation, normally resistant to landsliding, occurs as a sheared faulted block within the Pelican Hills fault zone, and as a consequence, has produced several large landslides. The Capistrano siltstone is notorious for large landslides in southern Orange County, where it underlies vast areas of hillside terrain. In Newport Beach, this formation is limited to scattered outcrops along the western bluffs of Newport Bay, and is covered by a protective cap of marine terrace deposits. Consequently, large landslides are not present, and slope instability is generally limited to surficial failures. Surficial slumps and slides are too small to map at the scale used in Plate 3-1, however they are common within the hills, typically occurring in the thick soils and deeply weathered bedrock near the base of steep slopes. Soil slips are common throughout the • hills during winters of particularly heavy and prolonged rainfall. Much of the accumulated sediment in canyon bottoms, as well as small sediment fans at the mouths of tributary drainages, was probably deposited in mud slurries or debris flows. Catastrophic debris flows, however, have not been reported for the Newport Beach area, probably because most development in the City occurs on elevated areas, rather than vulnerable locations at the base of natural slopes and in canyon bottoms. Slopes that are the most susceptible to creep are those composed of weak, fine-grained geologic materials, similar to those that are susceptible to landsliding. Fills slopes constructed with materials excavated from these bedrock units may also show signs of creep over time. 3.4.1.2 Susceptibility to Slope Failure Despite the abundance of landslides and recent spread of new development into the San Joaquin Hills, damage from slope failures in Newport Beach has been small compared to other hillside communities. This can probably be attributed to the development of strict hillside grading ordinances, sound project design that avoids severely hazardous areas, soil engineering practices that include detailed preliminary investigations and oversight during grading, and effective agency review of hillside grading projects. The recent trend toward saving biologically rich canyon habitats has the added benefit of keeping developments out of the path of potential slope failures. . Nevertheless, developments at the top of natural slopes may also be impacted by slope failures. Even if a slope failure does not reach the properties above, the visual impact will Earth Consultants International Geologic Hazards Page 3-19 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • generally cause alarm to homeowners. The City's remaining natural hillsides and coastal bluff areas are generally vulnerable to the types of slope instability mentioned above. Table 3-1 below is a summary of the geologic conditions in various parts of the City that provide the environment for slope instability to occur. These conditions usually include such factors as terrain steepness, rock or soil type, condition of the rock (such as degree of fracturing and weathering), internal structures within the rock (such as bedding, foliation, faults) and the prior occurrence of slope failures. Catalysts that ultimately allow slope failures to occur in vulnerable terrain are most often water (heavy and prolonged rainfall), erosion and undercutting by streams, man-made alterations to the slope, or seismic shaking. The summary in Table 3-1 was derived from the Geologic Map (Plate 3-1 a), the Fnaineerina Materials Man (Plate 3-2) and the Slope Distribution Map (Plate 3-3). The n LJ • Earth G 2003 • 0 • NOTES This map is intended for general land use planning only. Information on this map Is not sufficient to serve as a substitute for detailed geologic investigations of individual sites, nor does it satisfy the evaluation requirements set torn In geologic hazard regulations. Earth consultants International (ECI) makes no representations or warranties regarding the accuracy of the date from which these maps were derived. ECI shall not be liable under any circumstances for any direct, indirect. special, incidental, or consequential damages with respect to any claim by any user or third party on account of, or arising from, the use at this map. General Slope Instability Potential Area Geologic Conditions I Topes of San Joaquin Moderate to steep natural slopes, many in Hills excess of 26 degrees along stream channels; Highly fractured, sheered, faulted, and maned bedrock; Bedrock formations composed of clays and sifts having week shear resistance; Soils and loose cabins st the toes of slopes and in drainage courses; Abundant small to large existing landslides. Bluffs along - Uppar Moderate to locally steep slopes, marry In Newport Bay, the range of 26 degrees or more; Newport Highly fractured and jointed sihstone, Harbor,and mudetone, and shale in the lower pad, the Pacific sand and silly sand (marine terrace deposits) in the upper pod; Ocean Soils and loose debris in tributary drainages and swales. Brost common: Soll slips on steep slopes, soil slumps and small slides on the edges of active stream channels; small debris or mud flows in canyons. Less Common: Large, deep-seated landslides. Least Common: Rockfalls in areas where rocky outomps of resistant, unweathered intrusive rocks are present. Moat Common: Soil slips and slumps on moderate to steep slopes and in drainage swales, especially during periods of heavy rainfall. Spalling of coastal bluffs from wave erosion. Less Common: Small mud goers in canyons and rav nes. Least Common: I arnw dw„n.cwalad la ndc1ir% Slope Instability Map Newport Beach, California EXPLANATION Slope Instability Rating Very High High Mapped Landslide Newport Beach City Boundary Sphere of Influence Scale: 1:60,000 0,5 O O.S 1 1 Miles 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from Sure!MAPS RASTER Source. Based on data from Morton et al., 1976 and Morton. 1999 s ; Earth '— Consultants International Project Number: 2112 Date: July, 2003 Plate 3-4 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 3.4.1.3 Mitigation of Slope Instability in Future Development All proposed projects should require a site -specific geotechnical evaluation of any slopes that may impact the future use of the property. This includes existing slopes that are to remain, and any proposed graded slopes. The investigation typically includes borings to collect geologic data and soil samples, laboratory testing to determine soil strength parameters, and engineering calculations. Numerous soil -engineering methods are available for stabilizing slopes that pose a threat to development. These methods include designed buttresses (replacing the weak portion of the slope with engineered fill); reducing the height of the slope; designing the slope at a flatter gradient; and adding reinforcements such as soil cement or layers of geogrid (a tough polymeric net -like material that is placed between the horizontal layers of fill). Most slope stabilization methods include a subdrain system to remove excessive ground water for the slope area. If it is not feasible to mitigate the slope stability hazard, building setbacks are typically imposed. Temporary slope stability is also a concern, especially where earthwork construction is taking place next to existing improvements. Temporary slopes are those made for slope stabilization backcuts, fill keys, alluvial removals, retaining walls, and utility lines. The risk of slope failure is higher in temporary slopes because they are generally cut at a much steeper gradient. In general, temporary slopes should not be cut steeper than 1:1 (horizontal:vertical), and depending on field conditions flatter gradients may be necessary. The potential for slope failure can also be reduced by cutting and filling large excavations in segments, and not leaving temporary excavations open for long periods of time. The stability of large temporary slopes should be analyzed prior to construction, and mitigation • measures provided as needed. For debris flows, assessment of this hazard for individual sites should focus on structures located or planned in vulnerable positions. This generally includes canyon areas; at the toes of steep, natural slopes; and at the mouth of small to large drainage channels. Mitigation of soil slips, earth -flows, and debris flows is usually directed at containment (debris basins), or diversion (impact walls, deflection walls, diversion channels, and debris fences). A system of baffles may be added upstream to slow the velocity of a potential debris flow. Other methods include removal of the source material, placing subdrains in the source area to prevent pore water pressure buildup, or avoidance by restricting building to areas outside of the potential debris flow path. There are numerous methods for mitigating rock falls. Choosing the best method depends on the geological conditions (i.e., slope height, steepness, fracture spacing, bedding orientation), safety, type and cost of construction repair, and aesthetics. A commonly used method is to regrade the slope. This ranges from locally trimming hazardous overhangs, to completely reconfiguring the slope to a more stable condition, possibly with the addition of benches to catch small rocks. Another group of methods focuses on holding the fractured rock in place by draping the slope with wire mesh, or by installing tensioned rock bolts, tie -back walls, or even retaining walls. A third type of mitigation includes catchment devices at the toe of the slope, such as ditches, walls, or combinations of both. Designing the width of the catchment structure requires analysis of how the rock will fall. For instance, the slope gradient and roughness of the slope determines if rocks will fall, • bounce, or roll to the bottom (Wyllie and Norrish, 1996). Earth Consultants International Geologic Hazards Page 3-22 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 3.4.1.4 Mitigation of Slope instability in Existing Development There are a number of options for management of potential slope instability in developed hillsides. Implementation of these options should reduce the hazard to an acceptable level, including reducing or eliminating the potential for loss of life or injury, and reducing economic loss to tolerable levels. Mitigation measures may include: Protecting existing development and population where appropriate by physical controls such as drainage, slope -geometry modification, protective barriers, and retaining structures; Posting warning signs in areas of potential slope instability; Encouraging homeowners to install landscaping consisting primarily of drought - resistant, preferably native vegetation that helps stabilize the hillsides; Incorporating recommendations for potential slope instability into geologic and soil engineering reports for building additions and new grading; and Providing public education on slope stability, including the importance of avoiding heavy irrigation and maintaining drainage devices. US Geological Survey Fact Sheet FS-071-00 (May, 2000) and California Geological Survey Note 33 (November, 2001) provide public information on landslide and mudslide hazards. 3.4.2 Compressible Soils Compressible soils are typically geologically young (Holocene age) unconsolidated sediments of low density that may compress under the weight of proposed fill . embankments and structures. The settlement potential and the rate of settlement in these sediments can vary greatly, depending on the soil characteristics (texture and grain size), natural moisture and density, thickness of the compressible layer(s), the weight of the proposed load, the rate at which the load is applied, and drainage. Areas of the City where compressible soils are most likely to occur are the active and recently active stream channels, estuary deposits, beach and dune deposits, and young alluvial fan deposits. In the San Joaquin Hills, compressible soils are commonly found in canyon bottoms, swales, and at the base of natural slopes. Landslide deposits may also be compressible, particularly at the head or graben area and along the margins. Deep fill embankments, generally those in excess of about 60 feet deep, will also compress under their own weight. 3.4.2.1 Mitigation of Compressible Soils When development is planned within areas that contain compressible soils, a geotechnical soil analysis is required to identify the presence of this hazard. The analysis should consider the characteristics of the soil column in that specific area, and also the load of any proposed fills and structures that are planned, the type of structure (i.e. a road, pipeline, or building), and the local groundwater conditions. Removal and recompaction of the near -surface soils is generally the minimum that is required. Deeper removals may be needed for heavier loads, or for structures that are sensitive to minor settlement. Based on the location -specific data and analyses, partial removal and recompaction of the compressible soils is often performed, followed by settlement monitoring for a number of months after additional fill has been placed, but before buildings or infrastructure are constructed. Similar methods are used for deep fills. In cases where it is not feasible to • remove the compressible soils, buildings can be supported on specially engineered foundations that may include deep caissons or piles. Earth Consultants International Geologic Hazards Page 3-23 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 3.4.3 Collapsible Soils Hydroconsolidation or soil collapse typically occurs in recently deposited, Holocene -age soils that accumulated in an arid or semi -arid environment. Soils prone to collapse are commonly associated with wind -deposited sands and silts, and alluvial fan and debris flow sediments deposited during flash floods. These soils are typically dry and contain minute pores and voids. The soil particles may be partially supported by clay, silt or carbonate bonds. When saturated, collapsible soils undergo a rearrangement of their grains and a loss of cementation, resulting in substantial and rapid settlement under relatively light loads. An increase in surface water infiltration, such as from irrigation, or a rise in the groundwater table, combined with the weight of a building or structure, can initiate rapid settlement and cause foundations and walls to crack. Typically, differential settlement of structures occurs when landscaping is heavily irrigated in close proximity to the structure's foundation. The Holocene sediments that underlie the Newport Beach area are generally not susceptible to this hazard due to the granular nature of the soils, and the lack of clay that is needed to form the dry strength bonds between grains. However, variation in grain size within alluvial deposits in common. Therefore, localized areas could support the conditions needed for collapse to occur. 3.4.3.1 Mitigation of Collapsible Soils The potential for soils to collapse should be evaluated on a site -specific basis as part of the • geotechnical studies for development. If the soils are determined to be collapsible, the hazard can be mitigated by several different measures or combination of measures, including excavation and recompaction, or pre -saturation and pre -loading of the susceptible soils in place to induce collapse prior to construction. After construction, infiltration of water into the subsurface soils should be minimized by proper surface drainage design, which directs excess runoff to catch basins and storm drains. 3.4.4 Expansive Soils Fine-grained soils, such as silts and clays, may contain variable amounts of expansive clay minerals. These minerals can undergo significant volumetric changes as a result of changes in moisture content. The upward pressures induced by the swelling of expansive soils can have significant harmful effects upon structures and other surface improvements. Most of the Newport Mesa and Corona Del Mar areas are underlain by marine terrace deposits and young alluvial fan sediments that are composed primarily of granular soils (silty sand, sand, and gravel). Such units are typically in the low to moderately low range for expansion potential. However, thick soil profiles developed on the older marine deposits exposed west of Newport Bay are typically clay -rich and will probably fall in the moderately expansive range. Areas underlain by beach and dune sands have very little expansion potential. Potentially expansive bedrock may be exposed on natural slopes and ridges in the San Joaquin Hills, or may be uncovered by grading cuts made for developments. Topsoils is developed on fine-grained bedrock formations will also be moderately to highly expansive. Earth Consultants International Geologic Hazards Page 3-24 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • In some cases, engineered fills may be expansive and cause damage to improvements if such soils are incorporated into the fill near the finished surface. 3.4.4.1 Mitigation of Expansive Soils on The best defense against this hazard in new developments is to avoid placing expansive soils near the surface. If this is unavoidable, building areas with expansive soils are typically "presaturated" to a moisture content and depth specified by the soil engineer, thereby "pre -swelling" the soil prior to constructing the structural foundation or hardscape. This method is often used in conjunction with stronger foundations that can resist small ground movements without cracking. Good surface drainage control is essential for all types of improvements, both new and old. Property owners should be educated about the importance of maintaining relatively constant moisture levels in their landscaping. Excessive watering or alternating wetting and drying can result in distress to improvements and structures. 3.4.5 Ground Subsidence Ground subsidence is the gradual settling or sinking of the ground surface with little or no horizontal movement. Most ground subsidence is man -induced. In the areas of southern California where significant ground subsidence has been reported (such as Antelope Valley, Murrieta, and Wilmington, for example) this phenomenon is usually associated with the extraction of oil, gas or ground water from below the ground surface in valleys filled with recent alluvium. • Ground -surface effects related to regional subsidence can include earth fissures, sinkholes or depressions, and disruption of surface drainage. Damage is generally restricted to structures sensitive to slight changes in elevations, such as canals, levees, underground pipelines, and drainage courses; however, significant subsidence can result in damage to wells, buildings, roads, railroads, and other improvements. Subsidence has largely been brought under control in affected areas by good management of local water supplies, including reducing pumping of local wells, importing water, and use of artificial recharge (Johnson, 1998; Stewart et al., 1998). No significant regional subsidence as a result of either groundwater pumping or oil extraction has been reported in the literature for the Newport Beach area. The San Joaquin Hills -Newport Mesa uplift is generally not considered to be a part of the regional ground water supply. Consequently, ground subsidence is not considered a concern in this area. 3.4.6 Erosion Erosion is a significant concern in Newport Beach, especially along the shoreline, where beach sediments and coastal bluffs are highly susceptible to erosion by wave action, as discussed in Chapter 1, Coastal Hazards. Other parts of the City, including bluffs along Upper Newport Bay, canyon walls along tributary streams leading to the Bay, and slopes (both natural and man-made) within the San Joaquin Hills are also susceptible to the impacts from precipitation, stream erosion, and man's activities. 3.4.6.1 Mitigation of Erosion Erosion will have an impact on those portions of the City located above and below natural and man-made slopes. Ridge -top homes above natural slopes should not be permitted at Earth Consultants International Geologic Hazards Page 3-25 2003 C� HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • the head of steep drainage channels or gullies without protective mitigation. Although very limited development is present in canyons or major drainage channels, roadways and utility lines, out of necessity, must cross these areas and will need protection from erosion and sedimentation. This may include devices to collect and channel the flow, desilting basins, and elevating structures above the toe of the slope. Diversion dikes, interceptor ditches and slope down -drains are commonly lined with asphalt or concrete, however ditches can also be lined with gravel, rock, decorative stone, or grass. • There are many options for protecting manufactured slopes from erosion, such as terracing slopes to minimize the velocity attained by runoff, the addition of berms and v-ditches, and installing adequate storm drain systems. Establishing protective vegetation, and placing mulches, rock facings (either cemented on non -cemented), gabions (rock -filled galvanized wire cages), or building blocks with open spaces for plantings on the slope face. All slopes within developed areas should be protected from concentrated water flow over the tops of the slopes by the use of berms or walls. All ridge -top building pads should be engineered to direct drainage away from slopes. Temporary erosion control measures should be provided during the construction phase of a development, as required by current grading codes. In addition, a permanent erosion control program should be implemented for new developments. This program should include proper care of drainage control devices, proper irrigation, and rodent control. Erosion control devices should be field -checked following periods of heavy rainfall to assure they are performing as designed and have not become blocked by debris. 3.5 Summary of Issues The City of Newport Beach is highly diverse geologically. The central and northern parts of the City are situated on an elevated, relatively flat-topped mesa underlain by sands and gravel deposited on a prehistoric marine terrace. In contrast, the southern part of the City encompasses sedimentary bedrock now exposed in the steep slopes and narrow canyons of the San Joaquin Hills. During the latest period of glaciation and low sea levels, Upper Newport Bay was carved through the mesa by the collective downcutting of San Diego Creek and other streams emanating from the foothills to the northeast, while the Santa Ana River eroded the bluffs along the western edge of the mesa. As the sea level rose to its current level, the streams and rivers deposited their sediments, filling the Upper Newport Bay channel and forming beaches, dunes, sandbars and mudflats along the coast. The diversity of the area is strongly related to tectonic movement along the San Andreas fault and its broad zone of subsidiary faults. This, along with sea level fluctuations related to changes in climate, has resulted in a landscape that is also diverse in geologic hazards. Of these hazards, slope instability poses one of the greatest concerns, especially along coastal bluffs and in the steep -sided canyons of the San Joaquin Hills. Although relatively stable in historic times, bluffs along the beaches and bays are susceptible to erosion, heavy precipitation, and more recently, the adverse effects of increased runoff and irrigation from development. The history of instability in the natural slopes of the San Joaquin Hills is recorded in the abundant landslides that have occurred in nearly every bedrock formation. In addition, smaller slides, slumps, and mudflow Ift deposits are common throughout the hills, particularly during winters of heavy and prolonged Earth Consultants International Geologic Hazards Page 3-26 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • rainfall. As large new residential communities encroach deeper into the hills, slope instability is a major focus of geotechnical investigations, and remedial grading can involve moving thousands of cubic yards of earth. • Compressible soils underlie a significant part of the City, typically in the lowland areas and in canyon bottoms. These are generally young sediments of low density with variable amounts of organic materials. Under the added weight of fill embankments or buildings, these sediments will settle, causing distress to improvements. Low -density soils, if sandy in composition and saturated with water, will also be susceptible of the effects of liquefaction during a moderate to strong earthquake (see Chapter 2). Some of the geologic units in the Newport Beach area, including both surficial soils and bedrock, have fine-grained components that are moderate to highly expansive. These materials may be present at the surface or exposed by grading activities. Man-made fills can also be expansive, depending on the soils used to construct them. Losses resulting from geologic hazards are generally not covered by insurance policies, causing additional hardship on property owners. The potential for damage can be greatly reduced by: Strict adherence to grading ordinances — many of which have been developed as a result of past disasters; Sound project design that avoids severely hazardous areas; Detailed, site -specific geotechnical investigations followed by geotechnical oversight during grading and during construction of foundations and underground infrastructures; Effective agency review of projects; and Public education that focuses on reducing losses from geologic hazards, including the importance of proper irrigation practices, and the care and maintenance of slopes and drainage devices. Earth Consultants International Geologic Hazards 2003 Page 3-27 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Informational Websites and References Bates, R.L., and Jackson, J.A., 1987, editors, Glossary of Geology: American Geological Institute, Alexandria, Virginia, 788p. Barrie, D., Tatnall, T.S., and Gath, E., 1992, Neotectonic uplift and ages of Pleistocene marine terraces, San Joaquin Hills, Orange County, California; in Engineering geology field Trips: Orange County, Santa Monica Mountains and Malibu, Guidebook and Volume, 35th Annual Meeting, Association of Engineering Geologists, Southern California Section, pp. A- 55 to A-61. Bullard, T.F., and Lettis, W.R., 1993, Quaternary fold deformation associated with blind thrust faulting, Los Angeles basin, California: Journal of Geophysical Research, Vol. 98, pp. 8348-8369. California Division of Mines and Geology (CDMG), 1976, Environmental Geology of Orange County, California: Division of Mines and Geology Open -file Report 79-8 LA, 474p. California Division of Mines and Geology, 2001, Hazards from "mudslides", debris avalanches and debris flows in hillside and wildfire areas, DMG Note 33, available at http://www.consrv.ca.gov/dmg/pubs/notes/33/index.htm. Campbell, R.H., 1975, Soil slips, debris flows, and rainstorms in the Santa Monica Mountains and • vicinity, southern California: United States Geological Survey Professional Paper 851, 51 p. Clark, B.R., Zeiser, F.L., and Gath, E.M., 1986, Evidence for determining the activity level of the Pelican Hill fault, coastal Orange County, California; in Program with Abstracts, Association of Engineering Geologists, p. 146. Clarke, S.H., Jr., Greene, H.G., and Kennedy, M.P., 1985, Earthquake -related phenomena offshore in Ziony, I., (editor), Evaluating Earthquake Hazards in the Los Angeles Region: United States Geological Survey Professional Paper 1360, pp. 347-374. Earth Consultants International, Inc., 1997, Fault trenching investigation, Newport -Banning property, Orange County, California; Project No. 978100-019, dated November 25, 1997. Ellen, S.D., and Fleming, R.W., 1987, Mobilization of debris Flows from soil slips, San Francisco Bay region, California; in Costa, J.E. and Wieczorek, G.F. (editors), Debris flows/avalanches: Process, recognition, and mitigation: Geological Society of America Reviews in Engineering Geology, Vol. VII, pp. 31-40. FEMA, 2001, http://www.fema.gov/library/landsli.htm. Field, M.E., and Edwards, B.D., 1980, Slopes of the southern California continental borderland: A regime of mass transport in Field, M.E., Bouma, A.H., Colburn, I.P., Douglas, R.G., and Ingle, J.C., (editors), Proceedings of the Quaternary depositional environments of the • Pacific Coast: Pacific Coast Paleogeography Symposium No. 4: Los Angeles California Society of Economic Paleontologists and Mineralogists, Pacific Section, pp. 169-184. Earth Consultants International Geologic Hazards Page 3-28 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Grant, Lisa B., Mueller, K. J., Gath, E.M., Cheng, H., Edwards, R.L., Munro, R., Kennedy, G.L., 1999, Late quaternary uplift and earthquake potential of the San Joaquin Hills, southern Los Angeles Basin, California: Geology, November 1999, Vol. 27, No. 11, pp. 1031-1034, Guptil, P., Armstrong, C., and Egli, M., 1992, Structural features of West Newport Mesa; in Heath, E., and Lewis, L., (editors), The regressive Pleistocene shoreline, coastal southern California: South Coast Geological Society Annual Field Trip Guide Book No. 20, pp. 123- 136. Hauksson, E., and Gross, S., 1991, Source parameters of the 1933 Long Beach earthquake: Seismological Society of America Bulletin, Vol. 81, pp. 81-98. Keefer, D.K., and Johnson, A.M., 1983, Earth flows: Morphology, mobilization, and movement: United States Geological Survey Professional Paper 1264, 55p. Kuhn, G.G. and Shepard, F.P., 1985, Beach Processes and Sea Cliff Erosion in San Diego County, California: Handbook of Coastal Processes and Erosion, edited by Komar, P.D, CRC Press. Meier, M.F. 1984, Contribution of Small Glaciers to Global Sea Level: Science, Vol. 226, pp. 1418-1421. Mendenhall, W.C., 1905, Development of underground waters in the eastern coastal plain region • of Southern California: United States Geological Survey Water -Supply and Irrigation Paper No. 137. Mercer, J.H. 1970, Antarctic Ice and Interglacial High Sea Levels: Science, Vol. 168, pp. 1605- 1606. Miller, R.V., and Tan, S.S., 1976, Geology and engineering geologic aspects of the south half of the Tustin quadrangle, Orange County, California: California Division of Mines and Geology Special Report No. 126. Morton, P.K., Miller, R.V., Evans, 1.R., 1976, Environmental geology of Orange County, California: California Division of Mines and Geology Open -File Report 79-8 LA. Morton, P.K., and Miller, R.V., 1981, Geologic map of Orange County California, showing mines and mineral deposits: California Division of Mines and Geology Bulletin 204, Plate 1, scale 1:48,000. Morton, D.M., 1999, Preliminary digital geologic map of the Santa Ana 30' X 60, quadrangle, southern California, Version 1.0: United States Geological Survey Open -File Report 99- 172, Southern California Areal Mapping Project. Munro, R., 1992, Marine terraces along the frontal slopes of the Newport coast, Orange County, California; in Heath, E., and Lewis, L., (editors), The regressive Pleistocene shoreline, • coastal southern California, South Coast Geological Society Annual Field Trip Guide Book No. 20, pp. 105-113. Earth Consultants International Geologic Hazards Page 3-29 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Poland, J.F., and Piper, A.M., 1956, Ground -water geology of the coastal zone, Long Beach -Santa Ana area, California: U.S. Geological Survey Water -Supply Paper 1109. Reneau, S.L., and Dietrich, W.E., 1987, The importance of hollows in debris flow studies; examples from Marin County, California; in Costa, J.E. and Wieczorek, G.F. (editors), Debris flows/avalanches: Process, recognition, and mitigation: Geological Society of America Reviews in Engineering Geology, Vol. VII, pp. 165-179. Talley, C.H., Jr. and W. K. Cloud, (editors), 1962, United States Earthquakes, 1960: United States Coast and Geodetic Survey. Tan, S.S. and Edgington, W.J., 1976, Geology and engineering geologic aspects of the Laguna Beach quadrangle, Orange County, California: California Division of Mines and Geology Special Report 127. Tan, S.S., 1998, Slope failure and erosion assessment of the fire areas at Fillmore (April 1996) and Piru (August 1997), Ventura County, California: California Division of Mines and Geology Open -File Report 98-32. Toppozada, T.R., Real, C.R., and D.L. Parke, 1981, Preparation of Isoseismal Maps and Summaries of Reported Effects for Pre-1900 California Earthquakes: California Division of Mines and Geology Open File Report 81-11 SAC. • Trask, J.B., 1856, Untitled paper on earthquakes in California from 1812 to 1855: Proceedings of the California Academy of Natural Science, San Francisco, Vol. I, No. 2. U. S. Geological Survey, 1935, Newport Beach quadrangle, Scale 1:31,680. U. S. Geological Survey, 1948, Tustin, California quadrangle, 7.5 Minute Series (Topographic), Scale 1:24,000. U. S. Geological Survey, 1949, Newport Beach, California, quadrangle, 7.5 Minute Series (Topographic), Scale 1:24,000. U. S. Geological Survey, 1965 (Photorevised 1981), Newport Beach, California, quadrangle, 7.5 Minute Series (Topographic), Scale 1:24,000. U. S. Geological Survey, 1965 (Photorevised 1981), Laguna Beach, California, quadrangle, 7.5 Minute Series (Topographic), Scale 1:24,000. U. S. Geological Survey, 1965 (Photorevised 1981), Tustin, California quadrangle, 7.5 Minute Series (Topographic), Scale 1:24,000. U.S. Geological Survey, 2000, Landslide hazards, USGS Fact Sheet FS-071-00, available at http://greenwood.cr.usgs.gov/pub/fact-sheets.fs-071-00. • Earth Consultants International Geologic Hazards Page 3-30 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Vedder, J.G., Yerkes, R.F., and Schoelhamer, J.E., 1957, Geologic map of the San Joaquin Hill -San Juan Capistrano area, Orange County, California: United States Geological Survey Oil and Gas Investigations Map OM-193, scale 1:24,000. Vedder, J.G., 1975, Revised Geologic map, structure sections and well table, San Joaquin Hills - San Juan Capistrano area, California: United States Geological Survey Open -File Report 75-552. • Wells, W.G., 1987, The effects of fire on the generation of debris flows in Southern California; in Costa, J.E. and Wieczorek, G.F., (editors), Debris flows/avalanches: Process, recognition, and mitigation: Reviews in Engineering Geology, Vol. VII, Geological Society of America, pp. 105-114. Wood, H.O., 1916, California Earthquakes —A Synthetic Study of Recorded Shocks: Bulletin of the Seismological Society of America, Vol. 6, No. 2. Wright, T.L., 1991, Structural geology and tectonic evolution of the Los Angeles basin; in Biddle, K., (editor), Active margin basins: American Association of Engineering Geologists Memoir 52, pp. 35-134. Wyllie, D.C., and Norrish, N.I., 1996, Stabilization of rock slopes; in Turner, A.K., and Schuster, R.L. (editors), Landslides — investigation and mitigation: Transportation Research Board Special Publication 247, pp. 474-504. Earth Consultants International Geologic Hazards Page 3-31 2003 • • • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA CHAPTER 4: FLOODING HAZARDS Floods are natural and recurring events that only become hazardous when man encroaches onto floodplains, modifying the landscape and building structures in the areas meant to convey excess water during floods. Unfortunately, floodplains have been alluring to populations for millennia, since they provide level ground and fertile soils suitable for agriculture, and access to water supplies and transportation routes. Notwithstanding, these benefits come with a price — flooding is one of the most destructive natural hazards in the world, responsible for more deaths per year than any other geologic hazard. Furthermore, average annual flood losses (in dollars) have increased steadily over the last decades as development in floodplains has increased. The City of Newport Beach and surrounding areas are, like most of southern California, subject to unpredictable seasonal rainfall. Most years, the scant winter rains are barely sufficient to turn the hills green for a few weeks, but every few years the region is subjected to periods of intense and sustained precipitation that result in flooding. Flood events that occurred in 1862, 1884, 1916, 1938, 1969, 1978, 1980, 1983, 1988, 1992, 1995, and 1998 have caused an increased awareness of the potential for public and private losses as a result of this hazard, particularly in highly urbanized parts of floodplains and alluvial fans. As the population, in the area increases, there is an increased pressure to build on flood -prone areas, and in areas upstream of already developed areas. With increased development also comes an increase in impervious surfaces, such as asphalt. Water that used to be absorbed into the ground becomes runoff to downstream areas. If the storm drain systems are not designed or improved to convey these increased flows, areas that may have not flooded in the past may be subject to flooding in the future. This is especially true for developments at the base of the mountains and downstream from canyons that have the potential to convey mudflows. 4.1 Storm Flooding 4.1.1 Hydrologic Setting The City of Newport Beach can be divided into three geographic areas: 1) a low elevation area comprised of West Newport, Balboa Peninsula, and Newport Bay, 2) elevated marine terrace areas that include Newport Heights and Westcliff, and 3) high relief terrain of the San Joaquin Hills in the eastern portion of the City (these geographic areas are shown on Figure 4-1). The low elevation and terrace areas are generally drained by urbanized and relatively low relief streams that empty into Newport Bay. In contrast, rugged natural streams with steeper gradients drain the Newport Ridge and Newport Coast areas. For a map showing the landforms of Newport Beach, refer to Plate 4-1. San Diego Creek is the main tributary to Newport Bay (see Figure 4-2). Its headwaters lie about a mile east of the 1-5 — 1-405 intersection, at an elevation of about 500 feet. The creek flows westerly from its headwaters and empties into Newport Bay one mile west of the campus of the University of California at Irvine. Portions of San Diego Creek were channelized in 1968 for flood protection purposes. Earth Consultants International Flooding Hazards Page 4-1 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . Figure 4-2: Map Showing the Course of the Santa Ana River and Location of Newport Beach, Huntington Beach, Prado Dam, and the San Bernardino Mountains 1 .,.,T u• lea fSan Bemard(no Mlns � �Scn CmlvxJ /1 ty fsl f{unvir e1 � ^.c.'h �$',.� ( � ply' Itro M4W n u i\ & rur� Y(1" dni novae` : Y'•,^" 'L./ a ltdd..,,r bark } I:WiJ oMmtolm 2 C� ton' b ILTI!!rer � t Rmxxxb v t1 ar4bnAr Nnrrn« l (TIWne ? r wn ( e naRtJe " �q Prado rim Resorvolr er-n•v �. icM C. I.nbn }"Al ,oe� Afullnnry x/ar-x. NFv± Im'J i '7 oOrm6o NNr9 �1. �JJ Son.4x}nlob nee.11 ('sudPn C](elV CI 4N n'. % �`5+/ham v1, r,-..���Scansvndl4���.11�•I � �•1'gXmmmlr iego Huntington Hf San Cme 'P g Beac CT Mw Creek MN`i U < SFr \ � ' at eFwV•` Beach Nowporf Bay 'I", fl�'YYrR' 11_ IIT,r T� ,1)✓yy'L yn ALN C1I,I,IRno p ! ",V1,wiln (Figure adapted from Chin et al., 1991) 0 4.1.2 Meteorological Setting Average yearly precipitation in the Newport Beach area is about 12 inches (see Table 4-1), whereas 14 inches of precipitation fall annually in Santa Ana (Table 4-2). These tables show that areas closer to the coast receive a, little less precipitation, on average, than inland areas. Table 4-1: Average Annual Rainfall by Month for the Newport Beach Harbor Area Jan Feb Mar Apr Ma )un Jul AugSep I Oct Nov Dec Year Inches 1 2.5 2.4 1.9 1.1 0.2 1 0.1 1 0.0 1 0.1 1 0.3 1 0.3 1.2 2.0 11.9 Data based on 59 complete years between 1931 and 1995. Table 4-2: Average Annual Rainfall by Month for the Santa Ana Area Jan Feb jMarjAprjj AugSep Oct Nov Dec Year Inches 1 3.0 2.9 1 2.4 1 1.1 1 0.2 1 0.1 1 0.0 1 0.1 0.2 0.4 1.4 2.4 14.1 Data based on 64 complete years between 1931 and 1995. Source: littp://www.worldclimatc.com/ Earth Consultants International Flooding Hazards Page 4-3 2003 • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Figure 4-1: Shaded Relief Map Showing General Drainage Areas Within the City of Newport Beach • The largest coastal river in southern California, the. Santa Ana River, empties into the Pacific Ocean near West Newport and forms the boundary between the cities of Huntington Beach and Newport Beach. It originates high in the San Bernardino Mountains and drains an area of about 2,470 square miles (Chin et al., 1991). Near the town of Corona, the Santa Ana River flows into Prado Reservoir (Figure 4-2). Below Prado Dam, the river flows through Santa Ana Canyon, past highly urbanized cities in Orange County, and empties into the Pacific Ocean. Presently, 16.6 miles of the Santa Ana River, from its mouth to the city of Orange, are channelized for flood protection purposes. Prior to the extensive urbanization of Orange County (in-1950s), the Santa Ana River was actively building a large alluvial fan with its apex located at the mouth of Santa Ana Canyon around the city of Anaheim. However, channelization of the river has restricted any further alluvial deposition as the alluvial sediment is now confined to a narrow corridor. In addition to the Santa Ana River and San Diego Creek, the streams draining the San Joaquin Hills can also cause flooding potentially damaging to the City of Newport Beach. For example, flood hazards identified in Bonita Canyon, Big Canyon, Buck Gully, and Morning Canyon may impact new residential development along these streams (these streams are shown on Plate 4-1). Furthermore, a flood potential exists on smaller streams such as those draining Los Trancos Canyon and Muddy Canyon, albeit at a more localized scale. Flooding here is most likely restricted to the narrow floodplains along the channel margins. • Earth Consultants International Flooding Hazards Page 4-2 2003 • u • Nen'Pon>- 0i NOTES This map Is Intended for general land use planning only. Information on this map is not sufficient to serve as a substitute for detailed geologic invesligations of indirvidual sues, nor does it satisfy the evaluation requirements set forth In geologic hazere regulations. Earth Consultants International (ECI) makes no representations or warranties regarding the accuracy of the data from which these maps were derived. ECI shall not be liable under any circumstances for any direct. indirect, special, incidental, or consequential damages with respect to any claim by any user or third party on account of, or arising from, the use of this map. Geomorphic Map Newport Beach, California 4— 14 , EXPLANATION A J %i f� s e S' / n 1 ✓.i d' WO O h O �_ 1 y,,@D % 'P- `.rat' d �� _� Elevation (m) �Canyoit —.i .,� �� , �.: _ Newport Beach City Boundary ",�. _ E.^ .. tenet �.19 y Sphere of Influence Isiah y� Buck �. V� Peak oa CU/fy1� Sajn J°aqu h Scale: 1:60,000 �Pelican _ Hills 1 0 0.5 1 1.5 riill °c Miles xitometers o� °� .r a Source: US Geological Suvery 10 m Digital Elevation Pelican Point / "i ��� r/ Model (DEM) Cysts Cove r�rl i Reef Point - •� AdwEarth Consultants intemational -�� Project Number: 2112 �. �i�'�' Date: July, 2003 ♦r. Plate 4-1 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA isNot only does rainfall vary from one location to the next, often within short distances, but rainfall in southern California is extremely variable from year to year, ranging from one- third the normal amount to more than double the normal amount. Data reviewed for this study also suggest that southern California has experienced more wet years in the last 20 to 30 years than in the SO years prior. There are three types of storms that produce precipitation in southern California: winter storms, local thunderstorms, and summer tropical storms. These are described below. Winter storms are characterized by heavy and sometimes prolonged precipitation over a large area. These storms usually occur between November and April, and are responsible for most of the precipitation recorded in southern California. This is illustrated by the data on Tables 4-1 and 4-2. The storms originate over the Pacific Ocean and move eastward (and inland). The mountains, such as the Santa Ana, San Gabriel and San Bernardino Mountains, form a rain shadow, slowing down or stopping the eastward movement of this moisture. A significant portion of the moisture is dropped on the San Gabriel and San Bernardino Mountains as snow. If large storms are coupled with snowmelt from these mountains, large peak discharges can be expected in the main watersheds at the base of the mountains. Some of the severe winter storm seasons that have historically impacted the southern California area have been related to El Nino events. El Nino is the name given to a phenomenon that starts every few years, typically in December or early January, in the southern Pacific, off the western coast of South America, • but whose impacts are felt worldwide. Briefly, warmer than usual waters in the southern Pacific are statistically linked with increased rainfall in both the southeastern and southwestern United States, droughts in Australia, western Africa and Indonesia, reduced number of hurricanes in the Atlantic Ocean, and increased number of hurricanes in the Eastern Pacific. Two of the largest and most intense El Nino events on record occurred during the 1982-83 and 1997-98 water years. [A water year is the 12-month period from October 1 through September 30 of the second year. Often a water year is identified only by the calendar year in which it ends, rather than by giving the two years, as above.] These are also two of the worst storm seasons reported in southern California. Local thunderstorms can occur at any time, but usually cover relatively small areas. These storms are usually prevalent in the higher mountains during the summer (FEMA, 1986). Tropical rains are infrequent, and typically occur in the summer or early fall. These storms originate in the warm, southern waters off Baja California, in the Pacific Ocean, and move northward into southern California. 4.1.3 Stream Flow: Daily Mean and Past Floods 4.1.3.1 Daily Mean Flow In coastal Orange County, including the Newport Beach area, flooding is difficult to predict, and thus plan for, because rainfall varies from year to year. The small streams in the Newport Beach area are typical of the majority of the streams in southern California. Streamflow is negligible other than during and immediately after rains because climate and basin characteristics are not conducive to continuous flow. Similarly, the Santa Ana River • is dry most of the year, with small flows ranging from the 10s to 100s of cubic feet per Earth Consultants International Flooding Hazards Page 4-5 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • second (cfs) occurring only a few times a year. Figure 4-3a shows the location of USGS stream gage 11078000 on the Santa Ana River where it flows through the City of Santa Ana. Figure 4-3b shows that measurable discharge at this gage location occurred only 6 times during the 2001 water year. More frequent flows would occur under natural conditions, however impoundment of the upper Santa Ana River at Prado dam for flood control purposes causes the current flow regime. • Figure 4-3a: Map Showing Location of the Santa Ana Gage on the Santa Ana River L•1 ng Garden GroyO_ y _ -r cm rlycer, l� ants •Ana ( u Fount l alley "- Himt. n MM Roan!- _. -"I �f Figure 4-3b: Daily Mean Flow Hydrograph for the Santa Ana Gage for the 2001 Water Year (note that measurable flow occurred only 6 times during this water year) LISGR U078000 SANTA ANA R A SANT'A ANA CA N GOOD L 7000 t ROOD 5DVO w 0000 30DO 20DO x 1000 0 Nov 01 Jnn a Her 01 He9 01 Jul 01 Sm 01 Gn7m: 10F lmoo to o9/JOY2001 EPLMRTIM — MILY HEM S7MARFLON x HERSGRE➢ STREMFLGN — ESTIMTEG STREMFLM Source: http://waterdata.usgs.gov Earth Consultants International Flooding Hazards Page 4-6 2003 P • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA In contrast, San Diego Creek has more frequent moderate to large flows and maintains a regular base flow; a flow regime more typical of free -flowing streams. Mean daily flow data collected by stream gages maintained by the US Geological Survey (USGS) show that Lower San Diego Creek (near the University of California at Irvine campus) has maintained a baseflow of —20 cfs from 1978-1980 and from 1983-1986 (Figure 4-4). At the Lane Road gage, the average baseflow is approximately 10 cfs for the period of record from 1972 to 1978 (Figure 4-5). A similar rate has been measured at the Culver Road gage (Figure 4-6). It should be noted that a significant portion of the base flow in Lower San Diego Creek could be the result of runoff from residential and commercial irrigation and effluent from storm drains, rather than from precipitation. Figure 4-4a: Map Showing Location of the Campus Drive Gage Gartlm 0rot! A JJ Santa Ana ~—Fan nVall 1' — Co. SW 4-4b: Daily Mean Flow Hydrograph for this Gage Tutjn .thi ISli 0 UNO 11045955 BAN D1100 C A CAMPUS OR NA IRJINE CA atl N / j in 3000 ♦ E C l000 \ " Z'E1 T %SCatlan a a IOU 9 1999 1999 1900 1901 1902 19a3 190a 1905 00IM 10/01/1999 W 09430/1905 Source: http://waterdata.usgs.gov Figure 4-5a: Map Showing Location of the Lane Road Gage Figure 4-5b: Daily Mean Flow Hydrograph for this Gage to yt� Y�n Source: UEOI 1104EEE0 NW MEW C A LANE RC MR IRVINE CA Q 1993 1954 1939 1979 an 00IES: 04/01/1992 to 09/30/1932 http://waterdata.usgs.gov Earth Consultants International Flooding Hazards Page 4-7 2003 • • u HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA A Figure 4-6a: Map Showing Location of the Culver Drive Gage Figure 4-6b: Daily Mean Flow Hydrograph for this Gage ?� �ioetin oothi Is .� '111I11 Ma L %!✓ stl C a 3 0. G101 11048500 .AN 1IEGO C Rr CULVER .R N3 INVIN! CA' 4 � zsoo 1 g z000 C r two is two � � e +. L• DRTBZ IDMAM to wnonaos Source: http://waterdata.usgs.gov 1 .1.o 1.10 4.1.3.2 Past Floods: Implications for Existing Flood Hazard Flood hazards to the City of Newport Beach can be classified into two general categories: 1) flash flooding from small, natural channels and 2) more moderate and sustained flooding from the Santa Ana River and San Diego Creek. Flash floods are short in duration, but have high peak volumes and high velocities. This type of flooding occurs in response to the local geology and geography, and the built environment (human -made structures). The San Joaquin Hills in the eastern part of the City consist of sedimentary rock types that are fairly impervious to water so little precipitation infiltrates the ground; rainwater instead flows along the surface as runoff. When a major storm moves in, water collects rapidly and runs off quickly, making a steep, rapid descent from the hills into manmade and natural channels in the built environment and onto the marine terraces along the coast. The major streams emanating from the San Joaquin Hills (Big Canyon, Coyote Canyon, Bonita Canyon, Buck Gully, Morning Canyon, Los Trancos Canyon, and Muddy Canyon) do not have stream gages (Plate 4-1). Therefore, peak discharge data are not available for these drainages. Additionally, the areas around these canyons only recently became populated, so historic accounts of flooding are also unavailable. However, flooding on these streams likely occurs during major floods. For example, a flash flood in 1941 caused up to 6 feet of downcutting and undermined foundations in Laguna Canyon, approximately 3 miles southeast of Newport Beach (OCFCD photos in Storm Water Runoff, Photos from: 1916, 1927, 1934, 1938, 1940, & 1941). Although Laguna Canyon has a larger drainage area, channels in eastern Newport Beach probably experienced similar flooding in 1941 since both basins have similar characteristics and the storm intensity was comparable in both areas given their proximity. Earth Consultants International Flooding Hazards 2003 Page 4-8 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • San Diego Creek Flooding on San Diego Creek has historically caused significant damage in Newport Beach because it is the biggest stream, with a drainage area of 118 square miles, to flow through the City (Figure 4-7). Channelization of San Diego Creek also resulted in increased sediment flow into Upper Newport Bay, requiring extensive dredging projects to restore the ecosystem. As shown previously, the USGS maintained three stream gages along San Diego Creek. One of these, gage 111048500 on Culver Drive, was operated continuously from 10/01/1949 to 09/30/1985 (its location is shown on Figure 4-6a). These data provide a relatively long-term record of mean daily discharge and peak flows that can be used to describe the flooding history and future flooding potential of the Newport Beach area. I] Figure 4-7: Location Map Showing the San Diego Creek Watershed ' Wit u fv s t . 8 ry 01 Wave o t. pr nge County de Cpunt 14 irpi�n buw ` 5Frt. UGrOY mNt9tM�dt .+' I dswrLVfrro `. "B°ndt (t( `M1^ O L'011111)� cmr Djeg 7 0 7 14 N Miles The largest flood measured during the 36-year period of record occurred in 1983, when the Campus Drive gage measured a peak discharge of more than 15,000 cfs (Figure 4-8). A peak discharge of approximately 10,000 cfs was recorded 5 miles upstream at the Culver Drive gage during the same flood event (Figure 4-9). The next highest peak flows measured in the area date from 1980 (see Figure 4-9b). During the floods of February 24°i, 1969 Orange County received more than 6 inches of rain (Orange County Register 1/13/95). The gage on San Diego Creek at Culver Drive, measured a peak flow of about 6,700 cfs (Figure 4-9b). Flooding in 1969 washed out MacArthur Boulevard when the existing storm drain at jamboree Road was overwhelmed. High water also caused damage to Barranca Parkway near its intersection with Culver Road (Figure 4-10). Other roads and agricultural fields were also damaged by this event (Figure 4-11). Earth Consultants International Flooding Hazards 2003 Page 4-9 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Figure 4-8a: Map Showing Location of the Campus Drive Gage Figure 4-8b: Hydrograph Showing Peak Discharges at this Gage (for the periods 1978-1979 and 1983-1985) T.qn�°° 1' 09C8 11048555 BAN DIEGC C A CAMPH DR NA MINE CA �!/ 20000 (Santa stt)�� `• ;N Valley �; c * 15000 WS � I' •9• tj. _ j S arJ� 5 e 191E 1979 19R0 1911 398E 1903 19R0 39R5 Al 0 leJO j DRIES: 02/10/1970 ea II/2N1984 / Laa ate. Source: http://waterdata.usgs.gov Figure 4-9a: Map Showing Location of Culver Drive Gage • Figure 4-9b: Hydrograph Showing Peak Discharges at this Gage (for the period 1950-1985) J IR r r � �.. �` �M r �..• t s � �L R Y L"r- fi�:c� � . ' (�"`..+a•"� u�..�- � Y x '+r1�s��L �J� n{' ' ~� u'. jq��Y °'I'�'���v? t♦ � t+. rxJ � ,°"'r�. c'y'r n"xt' �T i � �' tiN.u... �y 4 .a+n r J,�y� j � a � M�;.Z,K•`�,Jk ' �• �; HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Santa Ana River The Santa Ana River is the largest drainage in southern California. The river has flooded historically many times, and the course of the river has changed, at times significantly, in response to these flooding events. For example, the river currently outlets into the Pacific Ocean near West Newport; however, between 1769, when the Spanish first arrived in southern California, and 1825, the Santa Ana River flowed out to sea through Alamitos Bay, near the present-day boundary between Los Angeles and Orange counties. In 1825, when severe storms caused extensive flooding in the area, the river resumed its ancient course through the Santa Ana Gap and around the toe of Newport Mesa to the ocean. Several other storms impacted the southern California area between 1770 and 1825 (in 1770, 1780, 1815, 1821, and 1822), but there are no records of flooding specific to the Santa Ana River. The largest documented flood in the Santa Ana River valley occurred in the winter of 1861-1862 when it rained nearly continuously for a month. Based on an account by Crafts (1906, as reported in Troxell et al., 1942), "the fall of 1861 was sunny, dry and warm until Christmas, which proved to be a rainy day. All through the holidays there continued what we would call a nice, pleasant rain, as it often rains in this section for days at a time. This . .. lasted until the 18'h of January, 1862, when there was a downpour for 24 hours or longer." This intense downpour destroyed settlements along the Santa Ana River from San Bernardino County to present day Santa Ana and created an inland sea, up to 4 feet deep in coastal Orange County. The river mouth swept as far to the southeast as the rock bluffs that today form the east side of the Newport Bay channel entrance. The peak discharge as • a result of this storm was estimated at 320,000 cfs (City of Huntington Beach, 1974) In 1867-1868, the area again experienced sustained precipitation, but of less intensity than that in 1862; therefore there was less damage. Then, in 1884, there were two floods. The first storm occurred in the latter part of February, saturating the ground. The second storm, which came six to eight days later, caused extensive damage. The Santa Ana River cut a new channel to the sea starting from near its confluence with Santiago Creek, cutting through farmlands east of the old channel, and discharging into the ocean about 3 miles southeast of its previous outlet. As much as 40 inches of rain were recorded in the area for that season (Troxell et al., 1942). Floods were also reported in the Los Angeles area in 1886, 1889, 1891, and in 1909. The 1909 floods caused significant damage in the upper reaches of the Santa Ana River, in San Bernardino and Riverside counties. Until 1919, the river's outlet to the sea continued to migrate back and forth from the rock bluffs in Newport Bay (U.S. Corps of Engineers, 1993) to a point near the present day intersection of Beach Boulevard and Pacific Coast Highway in Huntington Beach. In 1919, a year after a local flood, local interests built a dam at Bitter Point (which appears to have been located near present-day 57th Street and Seashore Drive) to stop the flow into Newport Bay, and cut a new outlet for the Santa Ana River, where it has remained to date. The most destructive flood in Orange County occurred in 1938. Intense storms brought heavy rainfall to Orange County and Newport Harbor. In the Santa Ana River drainage, the 1938 storms caused 34 deaths (nearly 100 deaths were reported throughout California), 1,159,000 acres of flooded land, more than 2,000 people homeless, and more than $14 million in damages (Feton, 1988; Troxell et al., 1942). Peak discharge in Santa Ana Earth Consultants International Flooding Hazards Page 4-12 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Canyon was estimated at 100,000 cfs. By the time floodwaters reached the city of Santa Ana, the discharge had attenuated to-46,000 cfs (Figure 4-12), which was still enough for the floodwaters to overtop the earthen levees and flood much of Huntington Beach and Newport Beach (Figure 4-13). • • Figure 4-12: Location and peak discharge hydrograph for the Santa Ana gage WNO 19000 0111 1107E000 IARTA RNA A R 1RNTR RNA CA 1990 19G0 1950 1990 1970 1989 1990 2000 UHIES: QnVI9Z/ L. 0111V2001 ittp://waterdata.usgs.gov The damage caused by the 1938 flood reinforced the need for an upstream flood control facility. Prado Dam was constructed near Corona in 1941 to greatly reduce the flooding hazard in coastal Orange County. Operation of the dam during large rain events has effectively limited flow in the lower Santa Ana River channel. In 1969, when the second largest storm of the 20"' century swept through southern California, Prado Dam was used to manage the flow into the lower reaches of the river: During this event 77,000 cfs flowed into Prado Dam, but only 6,000 cfs were released downstream (City of Huntington Beach, 1974). When flow from downstream tributaries (e.g., Santiago Creek) was added to the dam release, discharge measured at the gage in Santa Ana was limited to 20,000 cfs (Figure 4-12). This is a significant decrease compared to-46,000 cfs recorded at the same gage during the 1938 flood. In January and February 1980, California and Arizona were struck by several storm systems that brought much higher than normal precipitation to these areas. Between February 12 and February 20, the Prado Dam Flood Control Reservoir filled with approximately 100 acre-feet of water; between February 17 and February 26, daily mean discharges of more than 4,400 cfs were being measured at the Santa Ana gage. These continuous high discharges scoured that portion of the riverbed between 171h Street and Harbor Avenue to depths of up to 20 feet, and undercut segments of the concrete lining along the banks (Chin et al., 1991). Six major bridges and numerous smaller bridges were impacted by severe scour. Extensive scour of the piles supporting the Fifth Street bridge necessitated closure of this bridge for nearly a year while repairs were made (see Figure 4-14). Even Earth Consultants International Flooding Hazards 2003 Page 4-13 • • • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA higher peak discharges were recorded at the Santa Ana gage during the winters of 1983 and 1995 (see Figure 4-12). Figure 4-13. Oblique Aerial Photograph Looking West at the Mouth of the Santa Ana River During the 1938 Flood (Note the breaks in the levees at Verano Street and Adams Street and the inundation of West Newport and most of Huntington Beach.) b"I'M W0.11 c111rh 4t 1•Lnv: (Photograph from Troxell et al., 1942) 4.1.4 National Flood Insurance Program The Federal Emergency Management Agency (FEMA) is mandated by the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973 to evaluate flood hazards. To promote sound land use and floodplain development, FEMA provides Flood Insurance Rate Maps (FIRMS) for local and regional planners. Flood risk information presented on FIRMS is based on historic, meteorological, hydrologic, and hydraulic data, as well as topographic surveys, open -space conditions, flood control works, and existing development. Rainfall -runoff and hydraulic models are utilized by the FIRM program to analyze flood potential, adequacy of flood protective measures, surface -water and groundwater interchange characteristics, and the variable efficiency of mobile (sand bed) flood channels. It is important to realize that FIRMs only identify potential flood areas Earth Consultants International Flooding Hazards Page 4-14 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • based on the conditions at the time of the study, and do not consider the impacts of future development. Figure 4-14: The Santa Ana River at the Sth Street Bridge in Santa Ana, showing the riverbed prior to the 1980 floods (A), and the channel after the 1980 floods (B). The channel was scoured 18 to 20 feet deep, exposing the piles supporting the bridge. The bridge was closed for almost a year for repairs. (From Chin et al., 1991). • To prepare FIRMs that illustrate the extent of flood hazards in a flood -prone community, FEMA conducts engineering studies referred to as Flood Insurance Studies (FISs). Using information gathered in these studies, FEMA engineers and cartographers delineate Special Flood Hazard Areas (SFHAs) on FIRMs. SFHAs are those areas subject to inundation by.a "base flood" which FEMA sets as a 100-year flood. A 100-year flood is defined by looking at the long-term average period between floods of a certain size, and identifying the size of flood that has a 1 percent chance of occurring during any given year. This base flood has a 26 percent chance of occurring during a 30-year period, the length of most home mortgages. However, a recurrence interval such as "100 years" represents only the long- term average period between floods of a specific magnitude; rare floods can in fact occur at much shorter intervals or even within the same year. The base flood is a regulatory standard used by the National Flood Insurance Program (NFIP) as the basis for insurance requirements nationwide. The Flood Disaster Protection Act requires owners of all structures in identified SFHAs to purchase and maintain flood insurance as a condition of receiving Federal or federally related financial assistance, such as mortgage loans from federally insured lending institutions. The base flood is also used by Federal agencies, as well as most county and State agencies to administer floodplain management programs. The goals of floodplain management are to reduce losses caused by floods while protecting the natural resources and functions of the floodplain. The basis of floodplain management is the concept of the "floodway". • FEMA defines this as the channel of a river or other watercourse, and the adjacent land areas that must be kept free of encroachment in order to discharge the base flood without Earth Consultants International Flooding Hazards Page 4-15 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • cumulatively increasing the water surface elevation more than a certain height. The intention is not to preclude development, but to assist communities in managing sound development in areas of potential flooding. The community is responsible for prohibiting encroachments into the floodway unless it is demonstrated by detailed hydrologic and hydraulic analyses that the proposed development will not increase the flood levels downstream. • The NFIP is required to offer federally subsidized flood insurance to property owners in those communities that adopt and enforce floodplain management ordinances that meet minimum criteria established by FEMA. The National Flood Insurance Reform Act of 1994 further strengthened the NFIP by providing a grant program for State and community flood mitigation projects. The act also established the Community Rating System (CRS), a system for crediting communities that implement measures to protect the natural and beneficial functions of their floodplains, as well as managing the erosion hazard. The City of Newport Beach has participated as a regular member in the NFIP since September 1, 1978 a (City ID No. — 060227). The City's most current effective FIRM map dates from January 3, 1997. Since the City is a participating member of the NFIP, flood insurance is available to any property owner in the City. In fact, to get secured financing to buy, build, or improve structures in SFHAs, property owners are required to purchase flood insurance. Lending institutions that are federally regulated or federally insured must determine if the structure is located in a SFHA and must provide written notice requiring flood insurance. FEMA recommends that all property owners purchase and keep flood insurance. Keep in mind that approximately 25 percent of all flood claims occur in low to moderate risk areas. Flooding can be caused by heavy rains, inadequate drainage systems, failed protective devices such as levees, as well as by tropical storms and hurricanes (see Chapter 1). 4.1.5 Flood Zone Mapping As mentioned above, the City of Newport Beach has participated in the National Flood Insurance Program since 1978. The extent of flooding on the Santa Ana River, San Diego Creek, and a few smaller streams within Newport Beach has been analyzed through Flood Insurance Studies. The potential flood zones in the City mapped by FEMA are presented in Flood Insurance Rate Maps (FIRMS). Plate 4-2 shows the FIRM inundation limits for both the 100-year (in red) and 500-year (in blue) flood events. The 100-year Santa Ana River flood is anticipated to inundate the area from Beach Boulevard in Huntington Beach, to Fairview Park Bluffs in Costa Mesa and West Newport (Plate 4-2). Much of West Newport, from the Santa Ana River confluence to near City Hall will be flooded. The entire coastline will also be flooded. Only a narrow strip along Ocean Avenue will remain above water. The 100-year flood will be contained within the channel of San Diego Creek (Plate 4-2). However, floodwaters will overtop the channel banks in Bonita Canyon, on the Santa Ana Delhi Channel, and in the lower reaches of Big Canyon. Flooding will also occur along Buck Gully and within Buck Canyon, San Joaquin, and Bonita Reservoirs. Balboa Island will be underwater and property along the margins of Newport Bay will also be inundated. The 500-year flood event will inundate Ocean Avenue and flood all of West Newport up to the foot of the coastal bluffs that parallel Pacific Coast Highway. Earth Consultants International Flooding Hazards Page 4-16 2003 • • z + Wit, /. �,. "a E. NOTES This map is Intended for geneml land use planning only. Information on this map is no sumcient to serve as a substduto for detailed geologic investigations of Individual sites, nor does it satisfy the evaluation requirements set forth In geologic hazard regulations. Earth Consultants International (ECI) makes no representations or warranties regardin the accuracy of the data from which these maps were derived. ECI shall not be liable under any circumstances for any direct, indirect special, incidental, or consequential damages with respect to any claim by any user or th.rd party or account of, or arising from, the use of this mi r: J O A u i N Flood Zones Map Newport Beach, California EXPLANATION Special Flood Hazard Areas Inundated by 100-year flood. Areas of 500-year flood: areas of 100-year flood with average depths of less than 1 foot or with drainage areas less than 1 square mile; and areas protected by levees from 100- year flood. Newport Beach City Boundary Sphere of Influence Scale: 1:60,000 0.5 0 0.5 1 1.5 Miles 1 0 1 2 3 Kilometers Base Map: USGS Topographic Map from Sure! MAPS RASTER Source: Federal Emergency Management Agency, 1989a-f; 1997a-b. Earth Consultants Int nnational ,t uC Project Number: 2112 _ Date: July, 2003 Plate 4-2 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 4.1.6 Detailed Hydrologic Studies: Drainage Impact at Pacific Coast Highway Another source of flood information comes from detailed hydrologic studies that were performed as a requirement for Phase IV-2 of the Newport Coast Planned Community. The overall project was formerly called the Irvine Coast Planned Community before the land was annexed by the City of Newport Beach. This community encompasses much of the undeveloped land in the San Joaquin Hills, including the Muddy Canyon and Los Trancos Canyon watersheds (Figure 4-15). Figure 4-15. Map showing Los Trancos Canyon and Muddy Canyon Watersheds and Location of Phase IV-2 of the Newport Coast Planned Community • 0 Los Trancos Canyon is one of two predominantly undeveloped watersheds in Newport Beach. The headwaters originate near Signal Peak (at an elevation of 1,150 feet above sea level) and drain an 1,180-acre watershed. Prior to development near the mouth of Los Trancos Canyon, The Keith Companies (1987; as reported in LSA, 1998) calculated a 100- year discharge of 1,952 cfs. After development, the modeled 100-year discharge increased to 2,377 cfs, most likely due to increased runoff associated with impervious surfaces (John M. Tettemer and Associates, 1998). However, the construction of detention basins should decrease the 100-year discharge to 1,683 cfs at Pacific Coast Highway. A single 9-foot by 10-foot arch culvert drains these flows beneath PCH. However, recent widening of PCH necessitated extending this culvert. The highway improvements result in decreased conveyance through the culvert and a higher ponded water surface upstream of PCH. This condition increases the potential for flooding at the PCH crossing. Earth Consultants International Flooding Hazards Page 4-18 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Muddy Canyon is the other predominantly undeveloped watershed in Newport Beach. The Keith Companies (1987, as reported in LSA, 1998) calculated a pre -development 100- year discharge of 1,470 cfs for the 990-acre Muddy Canyon watershed. After development, the 100-year discharge increases to 1,908 cfs (Tettemer and Associates, 1998). However, like Los Trancos Canyon, detention projects will be constructed to reduce the post development 100-year discharge to only 1,008 cfs. A single 8-foot by 6-foot arch culvert drains floodwaters beneath PCH, but currently conveys less than the 100-year discharge. The post development 100-year water surface behind the culvert would be about 2 feet higher than the existing 100-year conditions. However, the culvert inlet will be modified so all of the 100-year discharge will be conveyed for the post development conditions. 4.1.7 Urban Street Flooding Urban street flooding is rarely a problem in the City of Newport Beach (Auger, 2003 personal communication). However, when heavy rainfall coincides with high tides, the low-lying streets in Newport Beach can become inundated. For example, when tides reach --6.5 feet and heavy rain is falling, the streets around the Marcus and Finley Tracts on Balboa Peninsula will flood. This condition also occurs along the lowest lying areas of Balboa Island. The City of Newport Beach operates a total of 89 tide valves. These valves are usually closed to keep high tides from flooding the streets on Balboa Island and on the Peninsula. During rainstorms, urban runoff is in effect dammed by these tide valves. To mitigate this • problem, the City pumps urban runoff ponded at the street ends into the ocean. This system has proven effective in minimizing the impacts of urban street flooding. 4.1.8 Bridge Scour Scour at highway bridges involves sediment -transport and erosion processes that cause streambed material to be removed from the bridge vicinity (see Figure 4-14). Nationwide, several catastrophic collapses of highway and railroad bridges have occurred due to scouring and a subsequent loss of support of foundations. This has led to a nationwide inventory and evaluation of bridges (Richardson and others, 1993). Scour processes are generally classified into separate components, including pier scour, abutment scour, and contraction scour. Pier scour occurs when flow impinges against the upstream side of the pier, forcing the flow in a downward direction and causing scour of the streambed adjacent to the pier. Abutment scour happens when flow impinges against the abutment, causing the flow to change direction and mix with adjacent main -channel flow, resulting in scouring forces near the abutment toe. Contraction scour occurs when flood -plain flow is forced back through a narrower opening at the bridge, where an increase in velocity can produce scour. Total scour for a particular site is the combined effects from all three components. Scour can occur within the main channel, on the flood plain, or both. While different materials scour at different rates, the ultimate scour attained for different materials is similar and depends mainly on the duration of peak streamflow acting on the material (Lagasse and others, 1991). • The State of California participates in the bridge scour inventory and evaluation program; however, to date, we have not found any records to indicate that the bridges in the Earth Consultants International Flooding Hazards 2003 Page 4-19 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Newport Beach area have been evaluated. Therefore, we analyzed aerial photographs to identify and evaluate bridges that may be susceptible to scour during storm events. We used the following assumption for this evaluation: Bridges that cross channelized streams have a lower risk of scour because the concrete lining of the bed and banks resists undermining and erosion of bridge piers; although in intense floods, the concrete lining can still fail. The lower reaches of the Santa Ana River have been entirely channelized; therefore damage due to bridge scour is low, but not completely unlikely, as evidenced by the damage caused by the 1980 floods. In contrast, all other streams in Newport Beach have earthen or riprap-covered beds and banks, which allow for bed erosion and potential loss of bridge support. The banks of San Diego Creek are comprised of earthen material with rock riprap sections near bridge crossings. The jamboree, Highway 73, and MacArthur bridge crossings could be threatened by scour during flooding of San Diego Creek. Similarly, Bonita Canyon has an engineered channel comprised of earthen banks and riprap bridge protection. The bridges at MacArthur Boulevard and Bison Avenue could also be at risk during storm flow. There are no significant bridges crossing Big Canyon, Buck Gully, Los Trancos Canyon, or Muddy Canyon, therefore bridge scour is not a concern along these streams. 4.1.9 Existing Flood Protection Measures During the past 70 years, private corporations, the Orange County Flood Control District (OCFCD), and the US Army Corps of Engineers have constructed several reservoirs in the San Joaquin Hills and Santa Ana Mountain foothills to minimize flood damage to • downstream areas, such as Newport Beach. The US Army Corps of Engineers has also made channel alterations consisting primarily of concrete side -slopes and linings for the Santa Ana River. These flood control structures are presently owned and operated by the OCFCD, which has jurisdiction over the majority of watercourses in the Newport Beach area, as well as the regional flood control system in Orange County. All of these structures help regulate flow in the Santa Ana River, San Diego Creek, and smaller streams and hold back some of the flow during intense rainfall periods that could otherwise overwhelm the storm drain system in Newport Beach. As previously discussed, flood control measures on the Santa Ana River have effectively mitigated flood damage in recent years, although the area has not been subjected to storms comparable to those of either 1938 or 1969, so the system has not yet been truly tested. 4.1.10 Future Flood Protection As developments, such as new phases of the Newport Coast Planned Community are considered, it is important that hydrologic studies be conducted to assess the impact that increased development may have on the existing development downgradient. These studies should quantify the effects of increased runoff and alterations to natural stream courses. Such constraints should be identified and analyzed in the earliest stages of planning. If any deficiencies are identified, the project proponent needs to prove that these can be mitigated to a satisfactory level prior to proceeding forward with the project, in accordance with the California Environmental Quality Act (CEQA) guidelines. Mitigation measures typically include flood control devices such as catch basins, storm drain pipelines, culverts, detention basins, desilting basins, velocity reducers, as well as debris • basins for protection from mud and debris flows. Earth Consultants International Flooding Hazards Page 4-20 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The methodology for analysis and design is set forth in several manuals published by the Orange County Public Facilities and Resources Department (OCPFRP). Future responsibilities for operation of regional flood control facilities will be with the OCPFRP, while the local storm drain network outside of the regional system will be with the City of Newport Beach. Therefore, both agencies must be involved in the planning and approval of mitigation measures, to assure compatibility. Across the United States, substantial changes in the philosophy, methodology and mitigation of flood hazards are currently in the works. For example: • Some researchers have questioned whether or not the current methodology for evaluating average flood recurrence intervals is still valid, since we are presently experiencing a different, warmer and wetter climate. Even small changes in climate can cause large changes in flood magnitude (Gosnold et al., 2000). Flood control in undeveloped areas should not occur at the expense of environmental degradation. Certain aspects of flooding are beneficial and are an important component of the natural processes that affect regions far from the particular area of interest. For instance, lining major channels with concrete reduces the area of recharge to the ground water, and depletes the supply of sand that ultimately would be carried to the sea to replenish our beaches. Thus there is a move to leave nature in charge of flood control. The advantages include lower cost, preservation of wildlife habitats and improved recreation potential. Floodway management design in land development projects can also include areas where stream courses are left natural or as developed open space, such as parks or golf courses. Where flood control structures are unavoidable, they are often designed with a softer appearance that blends in with the surrounding environment. Environmental legislation is increasingly coming in conflict with flood control programs. Under the authority of the Federal Clean Water Act and the Federal Endangered Species Act, development and maintenance of flood control facilities has been complicated by the regulatory activities of several Federal agencies including the U.S. Army Corps of Engineers, the Environmental Protection Agency, and the U.S. Fish and Wildlife Service. For instance, FEMA requires that Orange County and its incorporated cities maintain the carrying capacity of all flood control facilities and floodways. However, this requirement can conflict with mandates from the U.S. Fish and Wildlife Service regarding maintaining the habitat of endangered or threatened species. Furthermore, the permitting process required by the Federal agencies is lengthy, and can last several months to years. Yet, if the floodways are not permitted to be cleared of vegetation and other obstructing debris in a timely manner, future flooding of adjacent areas could develop. Zappe (1997) argues that reform of environmental laws is necessary to ease the burden on local governments, and ensure the health and safety of the public. In particular, Zappe calls for a categorical exemption from the Federal laws for routine maintenance and emergency repair of all existing flood control facilities. Earth Consultants International Flooding Hazards 2003 Page 4-21 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 4.1.11 Flood Protection Measures for Property Owners Although the flood hazard in the City of Newport Beach has traditionally been limited to West Newport and narrow zones along stream corridors, areas in the San Joaquin Hills maybe increasingly susceptible to flooding as a result of both increased development, and possibly an increasingly wetter climate. Property owners in these areas can make modifications to their houses to reduce the impact of flooding. FEMA has identified several flood protection measures that can be implemented by property owners to reduce flood damage. These include: installing waterproof veneers on the exterior walls of buildings; putting seals on all openings, including doors, to prevent the entry of water; raising electrical components above the anticipated water level improvements; and installing backflow valves that prevent sewage from backing up into the house through the drainpipes. Obviously, these changes vary in complexity and cost, and some need to be carried out only by a professional licensed contractor. For additional information and ideas, refer to the FEMA web page at www.fema.gov. Structural modifications require a permit from the City's Building Department. Refer to them for advice regarding whether or not flood protection measures would be appropriate for your property. 4.2 Seismically Induced Inundation 4.2.1 Dam Inundation • Seismically induced inundation refers to flooding that results when water retention structures, such as dams, fail due to an earthquake. Statutes governing dam safety are defined in Division 3 of the California State Water Code (California Department of Water Resources, 1986). These statutes empower the California Division of Dam Safety to monitor the structural safety of dams that are greater than 25 feet in dam height or have more than 50 acre-feet in storage capacity. Dams under State jurisdiction are required to have inundation maps that show the potential flood limits in the remote, yet disastrous possibility a dam is catastrophically breached. Inundation maps are prepared by dam owners to help with contingency planning; these inundation maps in no way reflect the structural integrity or safety of the dam in question. Dam owners are also required to prepare and submit emergency response plans to the State Office of Emergency Services, the lead State agency for the State dam inundation -mapping program. The City of Newport Beach is required by State law to have inplace emergency procedures for the evacuation and control of populated areas within the limits of dam. inundation. In addition, recent legislation requires real estate disclosure upon sale or transfer of properties in the inundation area (AB 1195 Chapter 65, June 9, 1998; Natural Hazard Disclosure Statement). Three dams located in the Newport Beach area fall under State jurisdiction. From west to east they include Big Canyon Reservoir, Bonita Reservoir, and San Joaquin Reservoir (see • Plate 4-3). These dams are owned by the City of Newport Beach, Irvine Ranch Water Earth Consultants International Flooding Hazards Page 4-22 2003 • • • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA District and the Irvine Water Company, respectively. They retain small reservoirs in the San Joaquin Hills. Portions of Newport Beach are threatened by flooding from Prado Dam, Santiago Creek Reservoir, Villa Park Reservoir, San Joaquin Reservoir, Big Canyon Reservoir and Harbor View Reservoir. Bonita Reservoir also has the potential to cause localized flooding in the City, but inundation limits due to failure of this structure were not available. If Seven Oaks Dam fails, the flow reportedly will be contained by Prado Dam Reservoir, and is therefore not expected to impact the City of Newport Beach. Each of these reservoirs is described further below. Prado Dam reservoir straddles the boundary between San Bernardino and Riverside counties and is located approximately 2 miles west of the City of Corona. This dam is an earth -filled, concrete capped structure that was completed in April 1941. The reservoir covers an area of 6,695 acres (www.sp1.usace.army.mil/), and has a spillway capacity of 383,500 acre-feet (www.spl.usace.army.mil/resreg/htdocs/prdo.htmi). Summary information on this dam and its reservoir is provided in Table 4-3, and for a picture of the dam, see Figure 4-16. The flood inundation path, should the dam fail, is shown on Plate 4- 3. if this dam failed catastrophically while full of water, the inundation area would impact much of Orange County including Newport Beach. Approximately 110,000 acres of residential, commercial, and agricultural land would be flooded. By the time floodwaters reached the ocean most areas from Long Beach to Newport Bay would be inundated. The flood would reach the city of Newport Beach 21.5 hours after dam failure (USACE, 1985) and cause flooding of West Newport along the Santa Ana Delhi Channel and San Diego Creek, and in Newport Bay as far south of Pacific Coast Highway (Plate 4-3). Table 4-3: Characteristics of Prado Dam and Reservoir Name: Prado _ _ De artment of Water Resources No. 9000-022 National ID No. CA10022 U.S. Army Corps of Engineers _Owner: Year Completed: 1941 _ _ Latitude; Longitude: V 33.89 ;-117.643 _ Crest Elevation: 566.0 feet _ Stream: Santa Ana River _ _ Dam Type: Earth -filled Parapet Type: N/A Crest Lengthy 2,280 feet Crest Width: 30 feet _ Total Freeboard: 23 feet _ Height above Streambed: 106 feet Material Volume: 3,389,000 cubic yards _ _ Storage Capacity 383,500 acre-feet at top of pool Drainage Area: 2,255 sq mi a Reservoir Area: 6,695 acres Earth Consultants International Flooding Hazards 2003 Page 4-23 • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Figure 4-16: View to the north of Prado Dam (to the right -center), and Prado Dam Reservoir in the background Seven Oaks Dam is an earth- and rock -filled dam located in San Bernardino County, approximately 8 miles northeast of the City of Redlands (see Figure 4-17). Construction of the dam was completed in November 1999. Seven Oaks Dam was designed to protect San Bernardino County from flooding and to work in conjunction with Prado dam, which is located approximately 41 miles downstream. The reservoir has a capacity of 145,600 acre-feet and covers an area of 780 acres when full. Summary information on this dam and its reservoir is provided in Table 4-4. The flood waters resulting from a Seven Oaks dam failure would be contained by Prado dam and therefore do not pose a threat to Newport Beach. Figure 4-17: View Upstream of Seven Oaks Dam • Earth Consultants International Flooding Hazards Page 4-24 2003 • 40 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Table 4-4: Characteristics of Seven Oaks Dam and Reservoir Seven Oaks _Name: Department of Water Resources No. 9001-324 ID No. CA10324 _National Owner: U.S. Army Corps of Engineers _Year Completed: 1999 Latitude; Longitude: 34.116 ; -117.3 Crest Elevation: 2610 feet Stream: Santa Ana River Dam Type: Rock _ Parapet Type: No Wall Crest Length: 2,630 feet Crest Width: 40 feet _ Total Freeboard: 30 feet Height: 550 feet Material Volume: 4,000,000 cubic yards Storage Capacity: 145,600 acre-feet Drainage Area: 176 sq mi Reservoir Area: 780 acres Santiago Creek Reservoir dam is an earth -filled structure that has a storage capacity of 25,000 acre-feet. It is located 7 miles east of the City of Orange. Santiago Creek is the largest tributary to the lower Santa Ana River with a drainage basin area greater than 100 square miles. Summary information on this dam and its reservoir is provided in Table 4-5. The flood inundation path through Newport Beach, should the dam fail, is shown on Plate 4-3. Earth Consultants International Flooding Hazards 2003 Page 4-25 • �J • Ili .i NOTES This map is intended for general land use planning only. Information on this map is not sufficiont to serve as a substitute for detailed geologic mvostigetions of individual sites, nor does it safety the evaluation requirements set forth In geologic hazard regulations. Earth Consultants International (ECI) makes no representations arwerranties regarding the accuracy of the date from which these maps were derived, ECI shall not be liable under any circumstances for any direct, indirect, special, Incidental, or consequential damages with respect to any claim by any user or third parry on account of, or arising from, the use of this map. Dam Failure ,. Inundation Map Newport Beach, California e EXPLANATION f . Harbor View Reservoir Failure Inundation Pathway El San Joaquin Reservoir Failure Bonita Inundation Pathway .Reservoir Villa Park Reservoir Failure Inundation Pathway Santiago Creek Reservoir Failure Inundation Pathway San Joaquin Prado Dam Failure Reservoir `, � Inundation Pathway Big Canyon Reservoir Failure Inundation Pathway JBig Canyon \'��_ Reservoir '\ Reservoi r Rarbor view Newport Beach City Boundary Reservoir •\ Sphere of Influence Scale: 1:60,000 0.5 0 0.5 1 1.5 Miles 0 1 2 3 r Kilometers Base Map: USGS Topographic Map from SureIMAPS ems' RASTER ' Source: California Office of Emergency Services IL Earth ,� a .� .�' Consultants F International �• m Project Number: 2112 , r, Date: July, 2003 Plate 4-3 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Table 4-5: Characteristics of the Santiago Creek Dam and Reservoir Name: Santiago Creek Department of Water Resources No. 75--000 _ National ID No. CA00298 Owner: Serrano Irri ation District & Irvine Ranch Water District Year Completed: 1933 Latitude; Longitude: 33.785 ;-117.723 Crest Elevation: 810 feet Stream: Santiago Creek Dam T e: Earth -filled Parapet Type: No wall Crest Length: 1,425 feet _ Width: 24 feet _Crest Freeboard: 16 feet _Total Height: 136 feet _ Material Volume: 789,0_00_cubic yards Storage Capacity: 25,000 acre-feet Drainage Area: 63.1 sq mi Reservoir Area: 650 acres Villa Park Reservoir dam is located 3.5 miles downstream of Santiago Creek Reservoir and 4 miles east of the City of Orange. Villa Park dam is an earth -filled structure that has a • storage capacity of 25,000 acre-feet. Summary information on this dam and its reservoir is provided in Table 4-6. The flood inundation path through Newport Beach, should the dam fail, is shown on Plate 4-3. Table 4-6: Characteristics of the Villa Park Dam and Reservoir Name: Villa Park Department of Water Resources No. _ 1012-000 National ID No. CA00829 _ Owner: County of Orange _ Year Completed: 1963 Latitude; Longitude: 33.815 ;-117.765 Crest Elevation: 584 feet Stream: Santiago Creek Dam Type: Earth -filled Parapet Type: No wall Crest Length: 119 feet Crest Width: 20 feet Total Freeboard: 18.3 feet Height: 118 feet Material Volume: 835,000 cubic yards _ Storage Capacity: 15,600 acre-feet _ Drainage Area: 83.4 sq mi _ Reservoir Area: 480 acres Earth Consultants International Flooding Hazards Page 4-27 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Harbor View Dam is a small earth -filled structure; its reservoir is usually empty and used primarily for flood control. It is located approximately 700 feet upstream of Harbor View School and has a storage capacity of 28 acre-feet. Summary information on this dam and its reservoir is provided in Table 4-7. The flood inundation path through Newport Beach, should the dam fail while full, is shown on Plate 4-3. • • Table 4-7: Characteristics of the Harbor View Dam and Reservoir Name: Harbor View Department of Water Resources No. 1012-002 National ID No. CA00830 _ Owner: County of Oran e Year Completed: 1964 Latitude; Longitude: 33.603 ;-117.865 Crest Elevation: 190 feet Stream: Jasmine Gulch _ Dam Type: Earth -filled _ _ _ Parapet Type_ No wall Crest Length: 330 feet Crest Width: 60 feet Freeboard: 20 feet _Total Height: 65 feet Material Volume: 63,000 cubic yards Storage Capacity: 28 acre-feet Drainage Area: 0.39 sq mi Reservoir Area: 3 acres San Joaquin Dam is an earth -filled structure with a clay lining and asphalt surfacing. It is located in Newport Beach approximately half a mile west of Pacific View Memorial Park. Its reservoir has a storage capacity of 3,036 acre-feet and an area of 50 acres. Summary information on this dam and its reservoir is provided in Table 4-8. The flood inundation path through Newport Beach, should the dam fail, is shown on Plate 4-3. Bonita Dam is an earth -filled structure located approximately one mile downstream (north) of San Joaquin Dam on Bonita Creek. Although it has the same reservoir area (50 acres) as San Joaquin Dam, it has a storage capacity of only 323 acre-feet. Summary information on this dam and its reservoir is provided in Table 4-9. The flood inundation path through Newport Beach, should the dam fail, is shown on Plate 4-3. Earth Consultants International Flooding Hazards Page 4-28 2003 • • n U HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Table 4-8: Characteristics of the San Joaquin Dam and Reservoir Name: San Joaquin Department of Water Resources No. 1029-000 National ID No. CA00853 Owner: Irvine Ranch Water District Year Completed: 196_6 _ Latitude; Longitude: 33.62 ;-117.842 Crest Elevation: 476 feet Stream: Tributary to Bonita Creek Dam Type: Earth -filled ParapetType_ No wall Crest Length: 873 feet — Crest Width: 30 feet Total Freeboard: 5.5 feet Hei ht: 224 feet _ Material Volume 1,911,000 cubic yards Storage Capacity: 3,036 acre-feet Drainage Area: 0.35 sq mi Reservoir Area: 50 acres Table 4-9: Characteristics of the Bonita Dam and Reservoir Name: Bonita Canyon Department of Water Resources No. 793-004 National ID No. CA00747 Owner: The Irvine Company Year Completed: 1938 Latitude; Longitude: 33.632 ;-117.848 Crest Elevation: 151 feet Stream: Bonita Creek Dam Type: Earth -filled Parapet Te: Nowall Crest Length: _ 331 feet Crest Width: 20 feet Total Freeboard: 8 feet Height: 51 feet Material Volume; 43,000 cubic yards Storage Capa 323acre-feet Drainage Area: 4.2 sq mi _ Reservoir Area: 50 acres Big Canyon Dam is an earth -filled, asphalt -lined structure that provides fire protection and drinking water to residents in Newport Beach. It has a storage capacity of 600 acre-feet and is located in a residential area near Pacific View Memorial Park and Lincoln School. Failure of this structure would reportedly produce a flood wave between 300 and 1,000 feet wide on its course to Newport Bay. The limits of the inundation area, should this facility fail catastrophically, are shown on Plate 4-3. However, failure is unlikely because a Earth Consultants International Flooding Hazards 2003 Page 4-29 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA seismic analysis of the Big Canyon Dam shows that it can withstand a maximum 41 magnitude earthquake (M = 7) on the Newport -Inglewood fault. This earthquake is anticipated to produce very strong ground motions, with a peak horizontal ground acceleration of 0.91g, in the area of the reservoir (URS, 2001). Summary information on this dam and its reservoir is provided in Table 4-10. • Table 4-10: Characteristics of the Big Canyon Dam and Reservoir Name: Big Canyon _Department of Water Resources No. 1058-000 ID No. CA00891 _ _National Owner: City of Newport Beach Year Completed: 1959 Latitude; Longitude: _ 33.61 ;-117.857� Crest Elevation: 308 feet Stream: Tributary of Big Canon Creek _ Dam Type: Earth -filled Para et Type: No wall Crest Length: 3824 feet V` Crest Width: 20 feet Total Freeboard: 5.5 feet Height. _ 65 feet Material Volume: 508,000 cubic yards Storage Capacity: 600 acre-feet Drainage Area: _ 0.04 sq mi Reservoir Area: 22 acres 4.2.2 Inundation From Above -Ground Storage Tanks Seismically induced inundation can also occur if strong ground shaking causes structural damage to aboveground water tanks. If a tank is not adequately braced and baffled, sloshing water can lift a water tank off its foundation, splitting the shell, damaging the roof, and bulging the bottom of the tank (elephant's foot) (EERI, 1992). Movement can also shear off the pipes leading to the tank, releasing water through the broken pipes. These types of damage occurred during southern California's 1992 Landers, 1992 Big Bear, and 1994 Northridge earthquakes. The Northridge earthquake alone rendered about 40 steel tanks non-functional (EERI, 1995), including a tank in the Santa Clarita area that failed and inundated several houses below. As a result of lessons learned from recent earthquakes, new standards for design of steel water tanks were adopted in 1994 (Lund, 1994). The new tank design includes flexible joints at the inlet/outlet connections to accommodate movement in any direction. Based on a review of 1999 aerial photographs of the City, there appears to be no above- ground water tanks in the City. However, at least one 3.4 million gallon reservoir is proposed in the Irvine Coast Development along Pelican Hill Road (The Irvine Company, 1988). Any above -ground storage tanks proposed and built in the City need to be designed to the most current seismic design standards for liquid storage tanks. Earth Consultants International Flooding Hazards Page 4-30 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 4.3 Summary of Issues, Planning Opportunities and Mitigation Measures Portions of the City of Newport Beach are susceptible to storm -induced flooding on the Santa Ana River and the other drainages that extend at last partly across the City. The 100- and 500-year flood zones have been identified by the Federal Emergency Management Agency, and are shown on Plate 4-2. These include the low-lying areas in West Newport at the base of the bluffs, the coastal areas around Newport Bay and all low-lying areas adjacent to Upper Newport Bay. 100- and 500-year flooding is also anticipated to occur along the lower reaches of Coyote Canyon, in the lower reaches of San Diego Creek and the Santa Ana Delhi Channel, and in a portion of Buck Gully. Most flooding along these second- and third -order streams is not expected to impact significant development. However, flooding in the coastal areas of the City will impact residential and commercial zones along West Newport, the Balboa Peninsula and Balboa Island and the seaward side of Pacific Coast Highway. Flooding as a result of coastal processes also poses a hazard to the City. This is discussed further in Chapter 1. The National Flood Insurance Program makes federally subsidized flood insurance available in communities that agree to adopt and enforce floodplain management ordinances to reduce future flood damage. Owners of all structures within the FEMA-mapped Special Flood Hazard Areas (100-year flood) are required to purchase and maintain flood insurance as a condition of receiving a federally related mortgage or home equity loan on that structure. Estimates indicate that 75 percent of households located in the 100-year floodplain do not have insurance. In addition, between 20 and 25 percent of the National Flood Insurance Program claims come from structures located outside the designated 100-year flood zone, where insurance is not required. As a • comparison, structures located in the 100-year flood plain have a 26 percent chance of being flooded over the course of a 30-year mortgage that experience a fire (4 percent chance in 30 years). National Flood Insurance is available in the City of Newport Beach; homeowners within the 500-year flood zones, and even outside these zones should be encouraged to buy flood insurance. To ensure public participation in the National Flood Insurance Program and support of City - funded mitigation measures, property owners need to be informed about the potential for flooding in their area, including flooding of access routes to and from their neighborhoods. Community outreach and public information programs that not only identify the hazards but provide potential solutions need to be prepared and made available. The Federal Emergency Management Agency (FEMA) has excellent materials that describe specific mitigation measures that can be implemented to reduce flood damage to residential structures. A community's success in responding to a natural disaster is also dependent on how well its government officials, residents, businesses, and institutions (schools, churches, social organizations) cooperate and coordinate together to make effective decisions. To accomplish this, the City can prepare and manage a list of businesses, organizations and individuals that can be called in for help during emergencies. For those portions of the 100- and 500-year flood zones that have already been developed, the City should implement flood warning systems and evacuation plans. This is especially important in the areas identified above, near the coast, especially the low-lying areas next to the tide valves, where water has the opportunity to pond until pumped into the ocean. Critical facilities such as schools should have evacuation plans in place that cover the possibility of flooding. Facilities • using, storing, or otherwise involved with substantial quantities of onsite hazardous materials should not be permitted in the flood zones, unless all standards of elevation, anchoring, and flood Earth Consultants International Flooding Hazards Page 4-31 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • proofing have been satisfied, and hazardous materials are stored in watertight containers that are not capable of floating. The City should continue to require that future planning for new developments consider the impact on flooding potential, as well as the impact of flood control structures on the environment, both locally and regionally. Flood control should not be introduced in the undeveloped areas at the expense of environmental degradation. Land development planning should continue to consider leaving watercourses natural wherever possible, or developing them as parks, nature trails, golf courses or other types of recreation areas that could withstand inundation. There are several flood retention and water storage structures that, should they fail catastrophically, have the potential to flood portions of the City. Several of these structures are located outside the City's boundaries, but their inundation zones extend through the City. Most potential inundation areas are coincident with the 100- and 500-year flood zones, in areas where residents are already required or encouraged to have flood insurance. However, failure of Prado Dam has the potential to impact the area by and south of the Newport Aquatic Center, an area not identified as within the 100-year flood zone. If Prado Dam failed, the City of Newport Beach is sufficiently far from the reservoir that it would take several hours for the floodwaters to reach the City, which would permit evacuation of the low-lying areas. The same is true for both Santiago Creek and Villa Park Reservoirs, although since both of these structures are closer to Newport Beach, it would take less time for the waters to reach the City. Failure of San Joaquin or Bonita Reservoirs is not anticipated to pose a significant impact, although portions of San Joaquin Hills Transportation Corridor would be flooded. • The structure that poses the highest risk to a small sector of the community is Harbor View Reservoir. Since this reservoir is located within Newport Beach, its failure would immediately impact those areas down gradient, within its inundation pathway. The reservoirs located in the San Joaquin Hills area of the City are not located astride any known active faults. However, all structures are underlain by the San Joaquin Hills thrust fault, which has the potential to generate very strong ground shaking in the hills (see Chapter 2). Since this thrust fault was only recently identified, these reservoirs were most likely not designed to withstand the near -source ground accelerations that this fault is believed capable of producing. As new data are generated on this fault, it would be advisable to revisit the design of these facilities, and implement a retrofit program if the analyses suggest that this is warranted. A seismic study recently conducted for Big Canyon Reservoir indicates that this reservoir can withstand the strong ground shaking expected in the area as a result of an earthquake on either the Newport -Inglewood or the San Joaquin Hills fault (URS, 2001). Earth Consultants International Flooding Hazards Page 4-32 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Informational Websites and References Websites addressing Flooding, Dam Inundation, and Erosion (Note: the information on some of these websites has been removed due to safety concerns; but may be posted again in the future in limited form). httl)://vuIcan.wr.usgs.gov/Glossary/Secliment/framework.litmI US Geological Survey Volcanic Observatory website list of links regarding sediment and erosion. htto://www.usace.armv. nil/r)Llblic.html#RePulatoY US Army Corps of Engineers website regarding waterway regulations. http•//crunch.te.c.ai my.m i i/n icl/webpages/n ici.cfm National Inventory of Dams. http://www.spl.usace.army.inil/re�Ere/hidocs/Briefingmain.html US Army Corps of Engineers website about reservoirs in the Los Angeles District. http://www.fenia.Sok,/fema/nfil2.htni FEMA website about the National Flood Insurance Program. littn://ceres.ca.gov/planninghilid/dam inundation.html • Dam inundation information provided by the California Office of Emergency Services httl2://www.worldclimate.com/ Precipitation rates at different rain stations in the world measured over time. http-//waterdata.0 gs.gov Stream gage measurements for rivers throughout the US. Auger, )., 2003, Personal Communication, Storm Drain and Street Sweeping Supervisor with the General Services Department of the City of Newport Beach. California Department of Water Resources, 1986, Statutes and Regulations Pertaining to Supervision of Dams and Reservoirs: Division of Safety of Dams, 46p. California Department of Water Resources, 1984, Dams within the Jurisdiction of the State of California: Division of Safety of Dams, Bulletin 17-84, 94p. California Governor's Office of Emergency Services, Dam Inundation Maps obtained at www.00s.ca.gov//. Cannon, S.H., 2001, Debris -Flow Generation From Recently Burned Watersheds: Bulletin of the • Association of Engineering Geologists, Vol. VII, No. 4., November, 2001, pp. 321-341. Earth Consultants International Flooding Hazards Page 4-33 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Chin, E.H., Aldrige, B.N., and Longfield, R.J., 1991, Floods of February 1980 in Southern California and Central Arizona: U.S. Geological Survey Professional Paper 1494, 126p. City of Huntington Beach Flood Study, 1974; http://www.hbsurfcity.com/history/floodhis.htm Davis, D. )., 1980, Rare and Unusual Postfire Flood Events Experienced Flood Events in Los Angeles County During 1978 and 1980; in Storms, Floods and Debris Flows in Southern California and Arizona 1978 and 1980: Proceedings of a Symposium, September 17-18, 1980, published by the National Academy Press. Ellen, S.D., and Fleming, R.W., 1987, Mobilization of Debris Flows from Soil Slips, San Francisco Bay region, California; in Costa, J.E. and Wieczorek, G.F. (editors), Debris Flows/Avalanches: Process, Recognition, and Mitigation: Geological Society of America Reviews in Engineering Geology, Vol. VII, pp. 31-40. Federal Emergency Management Agency, 1997, Flood Insurance Rate Maps (FIRMs) for the City of Newport Beach, California; Community Panels No. 06059-00046F, 06059-00054F and Index Map No. 06059C-INDO, dated January 3, 1997. Federal Emergency Management Agency, 1989, Flood Insurance Rate Maps (FIRMs) for the City of Newport Beach, California; Community Panels No. 06059-00047E, 06059-00055E, 06059-00062E, 06059-CSTD1, 06059-CSTD2, and 06059-CSTD3 dated September 15, 1989. • Feton, J.P., 1988, Newport Beach - The first Century, 1888-1988: City of Newport Beach Historical Society, Sultana Press, Brea, California. Gosnold, William D., Jr., LeFever, Julie A., Todhunter, Paul E., and Osborne, Leon F,, Jr., 2000, Rethinking Flood Prediction: Why the Traditional Approach Needs to Change: Geotimes, Vol. 45, No. 5, pp. 20-23. John M. Tettemer and Associates, 1998, Newport Coast Phase IV-2, Hydrology Analysis; Report dated February 1998. Keefer, D.K., Wilson, R.C., Mark, R.K., Brabb, E.E., Brown III, W.M., Ellen, S.D., Harp, E.L., Wieczorek, G.F., Alger, C.S., and Zatkin, R.S., 1987, Real -Time Landslide Warning During Heavy Rainfall: Science, Vol. 238, pp. 921-925. Keefer, D.K., and Johnson, A.M., 1983, Earth Flows: Morphology, Mobilization, and Movement: U.S. Geological Survey Professional Paper 1264, 55p. Lagasse, P.F., Schall, J.D., Johnson, F., Richardson, E.V., Richardson, J.R., Chang, F., 1991, Stream stability at highway structures: U.S. Department of Transportation No. FHWA-IP-90-014 Hydraulic Engineering Circular 20, 195p. LSA Associates, 1998, Environmental Impact Report: Phase IV-2 of the Newport Coast Planned . Community, Newport Coast Planning Areas 3A-2, 36, 14, MCDP Sixth Amendment and Coast Development Permit. Earth Consultants International Flooding Hazards Page 4-34 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • LSA Associates, Inc., 1991, Final Environmental Impact Report, San Joaquin Hills Planned Community, No. 517; dated February 26, 1991. Orange County Flood Control District, photos of Storm Water Runoff dating from 1916, 1927, 1934, 1938, 1940, and 1941. Reneau, S.L., and Dietrich, W.E., 1987, The Importance of Hollows in Debris Flow Studies; Examples from Marin County, California; in Costa, J.E. and Wieczorek, G.F. (editors), Debris Flows/Avalanches: Process, Recognition, and Mitigation: Geological Society of America Reviews in Engineering Geology, Vol. VII, pp. 165-179. Richardson, E.V., Harrison, L.J., Richardson, J.R., and Davis, S.R., 1993, Evaluating scour at bridges (2d ed.): U.S. Department of Transportation Hydraulic Engineering Circular 18, 132p. State of California, Office of Planning and Research (OPR), 1987, General Plan Guidelines. United States Army Corps of Engineers, 1985, Prado Dam Emergency Plan Inundation Map The Irvine Company, 1988, The Irvine Coast Master Coastal Development Permit (CDP); report dated January 8, 1988. • Troxell, H. C., et al., 1942, Floods of March 1938 in Southern California: U.S. Geological Survey Water Supply Paper 844. URS, 2001, Report of Findings, Seismic Analysis Program, Big Canyon Reservoir Newport Beach, California; report prepared for the City of Newport Beach Public Works Department — Utilities, dated July 2001. U.S. Army Corps of Engineers, Los Angeles District, November 1993, Condition Survey for Entrance Jetties, Newport Bay Harbor, Orange County, California. Waananen, A.O., 1969, Floods of January and February 1969 in Central and Southern California: U.S. Geological Survey Open File Report, 233p. Weber, F.H., 1980b, Landsliding and Flooding in Southern California During the Winter of 1979- 1980 (Principally February 13-21, 1980), California Division of Mines and Geology Open - File Report 80-3 LA, 69p. Wells, W.G., 1987, The Effects of Fire on the Generation of Debris Flows in Southern California; in Costa, J.E. and Wieczorek, G.F. (editors), Debris Flows/Avalanches: Process, Recognition, and Mitigation: Geological Society of America Reviews in Engineering Geology, Vol. VII, pp. 105-114. Wilson, R.C., 1997, Operation of a Landslide Warning System During the California Storm . Sequence of January and February 1993; in Larson, R.A., and Slosson, J.E. (editors), Storm - Induced Geologic Hazards: Case Histories from the 1992-1993 Winter in Southern Earth Consultants International Flooding Hazards Page 4-35 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • California and Arizona: Geological Society of America Reviews in Engineering Geology, Vol. XI, pp. 61-70. • • Zappe, D.P., 1997, Statement of the Riverside County Flood Control and Water Conservation District Regarding Impacts of the Endangered Species Act on Flood Control Activities; Witness Testimony made at the Resources Committee of the House of Representatives on April 10, 1997. The text of his statement is available on the web at http://resourcescommittee.house.gov/105cong/fu I lcomm/apr10.97/zappe.htm Earth Consul 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA CHAPTER 5: FIRE HAZARDS 5.1 Vegetation Fires Even though more wildfires occur in the West than in the rest of the country, wildfires are a significant hazard throughout the United States. The wildfire risk in the United States has increased in the last few decades with the increasing encroachment of residences and other structures into the wildland environment, the increasing number of people living and playing in wildland areas, and the enduring drought conditions that have affected some regions. Between 1990 and 1999 inclusive, there were on average 106,347 wildfires annually, for a combined average annual burn of nearly 3.65 million acres of brush (htpp://nifc.gov/fireinfo/1999/highlites.htm]). These fires are for the most part caused by people: between 1988 and 1997, human -induced fires burned nearly eight times more brush than fires caused by lightning. The number of wildland fires reported in Orange County also appears to be increasing; according to the Orange County Fire Authority, in 2002 the wildfire occurrence was 150 percent above the previous ten-year average. A wildfire that consumes hundreds to thousands of acres of vegetated property can overwhelm local emergency response resources. Under the right wind conditions, multiple ignitions can develop as a result of the wind transport of burning cinders (called brands) over distances of a mile or more. Wildfires in those areas where the wildland approaches or interfaces with the urban environment (referred to as the urban-wildland interface area or UWI area) can be particularly dangerous and complex, posing a severe threat to public and firefighter safety, and causing devastating losses of life and property. This is because when a wildland fire encroaches onto the built environment, ignited structures can then sustain and transmit the fire from one building to the • next. This is what happened at three of the most devastating fires in California: the Oakland Hills/Berkeley Tunnel fire of October 1991, the Laguna fire of 1970 in northern San Diego County, and the Laguna Beach fire of 1993. As a result of the Oakland Hills fire, 25 lives were lost and 2,900 structures were damaged, for a total of $1.7 billion in insured losses. The September 1970 fire, which was caused by downed power lines, burned 175,425 acres, destroyed 382 structures and killed 5 people. The Laguna Beach fire of 1993 destroyed 441 homes, but thankfully, no one died. What it is clear is that continuous planning, preparedness, and education are required to reduce the fire hazard potential, and to limit the destruction caused by fires. This is discussed in detail in this document. Large areas of southern California are particularly susceptible to wildfire due to the region's weather, topography and native vegetation. The typically mild, wet winters characteristic of our Mediterranean climate result in an annual growth of grasses and plants that dry out during the hot summer months. This dry vegetation provides fuel for wildfires in the autumn, when the area is intermittently impacted by Santa Ana (or Santana) winds, the hot, dry winds that blow across southern California in the late fall. These winds often fan and help spread fires in the region. Furthermore, many of the native plants common in the area have a high oil content that makes them highly flammable. 5.1.1 Historical Wildland Fires in the Area Regardless of the comments above, we should not forget that wildland fire is a natural process. Wildfires have been part of the natural ecosystem in the rolling hillsides of central and southern Orange County for millennia. In fact, some of the plants native to this area . require periodic burning to germinate and recycle nutrients that enrich the soils. Wildfires become an issue, however, when they encroach into developed areas, with a resultant loss Earth Consultants International Fire Hazards Page 5-1 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • of property, and even life. The City of Newport Beach defines a wildland fire hazard area as any geographic area that contains the type and condition of vegetation, topography, weather, and structure density that potentially increases the possibility of wildland fires (Section 9.04.050 of the City of Newport Beach Municipal Code). • The most devastating wildiand fire in this area in recent history was the Laguna Beach fire of 1993. The Laguna Beach fire, which was the result of arson, burned 14,437 acres and destroyed 441 homes. This fire is still ranked in the top ten worst wildland fires in California. The 1993 fire spread into the Newport Coast area that is now part of the City of Newport Beach. The area in Newport Beach burned by the 1993 fire is shown on Plate 5- 1. Some of the damage caused by the Laguna Beach fire is shown on Figures 5-1 and 5-2. Figure 5-1: View of Ridges and Hillsides Burned by the 1993 Laguna Beach Fire. According to records kept by the Orange County Fire Authority, the Niger fire of 1955 burned 1,606 acres, impacting the northeastern -most comer of the current boundaries of the City of Newport Beach. The 73 Fire of 2001 burned only 6.63 acres, but because it occurred along the 73 Freeway, where it had the potential to impact traffic, it is considered a significant wildland fire. The area in Newport Beach impacted by these two fires is also shown on Plate 5-1. There have been several other smaller, less significant wildland and vegetation fires in the Newport Beach area, but records of these are limited. Those that were recorded by the Orange County Authority between 1991 and 2001 are shown on Plate 5-1. In 2002 alone, the City of Newport Beach Fire Department responded to 30 brush/vegetation fires in their jurisdiction. The locations of these fires are not shown on Plate 5-1. • Earth Consultants International Fire Hazards Page 5-2 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Insert Plate 5-1: Historical Wildland Fires in the Newport Beach Area • Earth Consultants International Fire Hazards Page 5-3 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . Figure 5-2: Another View of Hillsides Burned by the 1993 Laguna Beach Fire. The fire spread up the canyon but several of the houses on the ridge were thankfully spared. • (Photograph courtesy of Mr. Robert Lemmer, Leighton & Associates) 5.1.2 Wildfire Susceptibility in the Newport Beach Area As the map of the area burned by the Laguna Beach fire (Plate 5-1) shows, the eastern portion of the City is susceptible to damage from wildland fire. In fact, portions of the Newport Beach region and surrounding areas to the north, east and southeast include grass- and brush -covered hillsides with significant topographic relief that facilitate the rapid spread of fire, especially if fanned by coastal breezes or Santa Ana winds. The fire hazard of an area is typically based on the combined input of several parameters. These conditions include: fuel loading (that is, the density and type of vegetation), topography (slope), weather, dwelling density, wildfire history, and whether or not there are local mitigation measures in place that help reduce the zone's fire rating (such as an extensive network of fire hydrants, fire -rated construction, fuel modification zones, etc.). That the eastern portion of Newport Beach and adjacent areas outside City limits are • Earth Consultants International Fire Hazards Page 5-4 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA susceptible to wildfires is not a surprise; they are vegetated with high fire hazard plants such as tall grasses and coastal sage scrub, include steep slopes and canyons, and are subjected to both strong seasonal Santa Ana wind conditions and westerly winds that can help transport embers up the southwest -facing canyons. During Santa Ana conditions, when winds in excess of 40 miles per hour (mph) are typical, and gusts in excess of 100 mph may occur locally, fire -fighting resources are likely to be stressed, reducing their ability to suppress fires. Even with no unusual wind conditions, fire department response can be hindered by heavy traffic during peak hours, and by the long travel distances in the canyon and hillside areas of the southeastern part of the City. Furthermore, with the transportation corridors that now cut through these fire -prone areas, and the establishment of natural preserves in the canyons, there is an increased potential for fires, both accidental and purposely set, to impact the region. Therefore, enhanced onsite protection for structures and people in and near these wildfire -susceptible areas is necessary. Plate 5-2 shows a wildfire susceptibility map for the City that is based on an analysis of the factors discussed above (vegetation, slope, and degree of development). The three wildland fire hazard zones proposed for the City are as follows: low/none, moderate, and high. The low/none fire hazard zone includes the extensively developed western portion of the City where relief is minimal, and where hardscape (concrete, asphalt and structures) and landscaping vegetation predominate. In the eastern portion of the City, the low hazard zone includes the San Joaquin Reservoir, the low-lying, gently sloped, developed areas along the Pacific Coast highway adjacent to the coastline, and inland areas where an extensive network of fire sprinklers, fire -retardant construction and vegetation management plans help reduce the fire hazard. The moderate fire hazard zones are areas of moderate relief at the interface with the more developed areas of the City, undeveloped or partially undeveloped areas where grasses predominate, and areas at the interface between high and very high fire hazard zones and low/none hazard zones. The high fire hazard zones include primarily the undeveloped canyon and hillside areas where native vegetation, including coastal sage scrub and tree assemblages predominate. Small moderate to high fire hazard areas not mapped may be present locally and sporadically within the low/none zone in the eastern part of the City, if a vacant lot is not maintained and dried grasses or other vegetation are not controlled. The Orange County Fire Authority had rated the Newport Coast area, now in the eastern one-third of the City, and the Moro Canyon area and surrounding hillsides to the east of the City, as Special Fire Protection Areas (SFPA). SFPAs are similar to the State's Very High Fire Hazard Severity Zones established in accordance with the Bates Bill (Assembly Bill 337, September 29, 1992 — an act that added Chapter 6.8, commencing with Section 51175, to Part 1 of Division 1 of Title 5 of the Government Code, and an amendment to Section 13108.5 of the Health and Safety Code). When the City of Newport Beach annexed the Newport Coast area, it adopted the Orange County Fire Authority's mapping for the area. The Fire Hazards Map adopted by the City is shown on Plate 5-3. However, due to the extensive development proposed in the far southeastern and northeastern corners of Newport Beach, the SFPA boundaries in Newport Beach are changing. Newer • SFPA boundaries are shown on Plate 5-4, which also shows the approximate boundaries of the proposed new developments. Earth Consultants International Fire Hazards Page 5-5 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . Insert Plate 5-2: Fire Hazard Zones in the City of Newport Beach 0 Earth Consultants International Fire Hazards Page 5-6 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA 0 Plate 5-3: Orange County Fire Authority's Special Fire Severity Zones in Newport Beach 0 Earth Consultants International Fire Hazards Page 5-7 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 5.1.3 Wildland Fire Protection Strategies 5.1.3.1 Vegetation Management Experience and research have shown that vegetation management is an effective means of reducing the wildland fire hazard. Therefore, in those areas identified as susceptible to wildland fire, land development is governed by special State and local codes, and property owners are required to follow maintenance guidelines aimed at reducing the amount and continuity of the fuel (vegetation) available. A recent, relatively local example of the effectiveness of these measures is the Antonio fire of May 2002 that burned 1,100 acres in the Las Flores area near Coto de Caza and Rancho Santa Margarita. Although the winds out of the west were blowing at only 10 to 15 miles per hour (mph), this was enough wind to fan the fire across a fairly large area in a short time. The fire even forced the closure of the 241 Toll Road for a few hours. Nevertheless, the fire did not damage any homes due in great measure to the strict vegetation management practices at the urban-wildland interface (UWI) that the local property owners are required to follow. Requirements for vegetation management at the UWI in California were revisited following the 1993 Laguna Beach fire. In July 1994, the Orange County Wildland/Urban Interface Task Force Report was completed, and shortly thereafter approved by the Orange County Board of Supervisors. In a companion effort, the International Fire Code Institute formed a committee to develop an Urban-Wildland Interface Code under the direction of the California State Fire Marshal. The first draft of this code was published in October 1995. In 1997, the City of Newport Beach adopted guidelines that mirror the Orange County Fire • Authority guidelines for hazard reduction and fuel modification. Hazard reduction and fuel modification are the two methods that the City of Newport Beach employs for reducing the risk of fire at the UWI. Both methodologies use the principle of reducing the amount of combustible fuel available, which reduces the amount of heat, associated flame lengths, and the intensity of the fire that would threaten adjacent structures. The purpose of these methods, adopted as part of the City's Municipal Code, is to reduce the hazard of wildfire by establishing a defensible space around buildings or structures in the area. Defensible space is defined by the City as "an area, either natural or man-made, where plant materials and natural fuels have been treated, cleared, or modified to slow the rate and intensity of an advancing wildfire, and to create an area for firefighters to suppress the fire and save the structure." These standards require property owners in the UWI to conduct maintenance, modifying or removing non -fire -resistive vegetation around their structures to reduce the fire danger. This affects any person who owns, leases, controls, operates, or maintains a building or structure in, upon, or adjoining the UWI. Fuel or vegetation treatments often used include mechanical, chemical, biological and other forms of biomass removal (Greenlee and Sapsis, 1996) within a given distance from habitable structures. The intent of this hazard reduction technique is to create a defensible space that slows the rate and intensity of the advancing fire, and provides an area at the urban-wildland interface where firefighters can set up to suppress the fire and save the threatened structures. Since the late 1980s, the Newport Beach Fire Department has been using hazard reduction in the canyons that extend across the older portions of the City, including the mouth of Big Canyon, Upper and Lower Buck Gully and Morning Canyon, and properties adjacent to Spyglass Canyon (see Plate 5-4). In total, 263 properties are maintained under the hazard reduction regulations. Earth Consultants International Fire Hazards Page 5-8 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Insert Plate 5-4: Hazard Reduction and Fuel Modification Zones in Newport Beach 0 0 Earth Consultants Intern 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The City standard for hazard reduction includes requirements for the maintenance of existing trees, shrubs, and ground cover within a 100-foot wide setback zone, to reduce the amount of fuel on those sides of any structure that face the UWI. These requirements are summarized below. Trees: All trees located within 100 feet of any portion of a structure, which is facing an UWI area, shall comply with the following guidelines: ✓ Existing trees are not required to have a separation of tree canopies but must be maintained free of all dead or dying foliage. ✓ The selection of any new trees shall be made from the City -approved Fire Resistive Plant list, and the trees shall be planted such that mature canopies will have a minimum separation of 10 feet. [This list, developed by the City in cooperation with the Orange County Fire Authority, includes trees, bushes, shrubs and ground cover that will slow the progress and intensity of a wildfire and do not contribute to the fire load.] The City considers branch tip to branch tip to be synonymous with the term canopy. Non -fire resistive plants and trees should not be used. The City's Fire Department has a list of these non -fire resistive plants that should be avoided. For additional information regarding the acceptable and non -acceptable plants to be used in fire hazardous areas, contact the Newport Beach Fire Department. ✓ All dead trees shall be removed. ✓ Where shrubs are located within the dripline of a tree, the lowest tree branch shall • be at least three times as high as the shrub. This process will remove the potential for fires to spread from lower shrubs and bushes to higher trees and structures. ✓ Trees extending to within 5 feet of any structure shall be pruned to maintain a minimum clearance of 5 feet. Shrubs and Bushes: All shrubs and bushes located within 100 feet of any portion of a building shall comply with the following guidelines: ✓ All dead and dying growth shall be removed from shrubs and bushes. ✓ All shrubs and bushes not on the City's Fire Resistive Plant list shall be maintained no closer than 10 feet apart, measured from branch tip to branch tip. ✓ One to three shrubs and bushes together in a small group can be considered a single bush if properly maintained. ✓ All shrubs, if of the types listed on the Fire Resistive Plant list, need not be separated if properly maintained. ✓ For the purpose of firefighter entrance and egress, provide 3 feet of access along both sides of the structure. Ground Cover: ✓ Ground cover that is properly planted, irrigated, and maintained is permitted within the defensible space. Earth Consultants International Fire Hazards Page 5-10 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • ✓ Non -planted areas may be covered with a minimum of 5 inches of chipped biomass or its equivalent. ✓ All ground cover that is either dead and/or dying shall be removed when located within 100 feet of the defensible space. Firewood: Firewood and combustible material for consumption on the premises shall not be stored in unenclosed spaces beneath buildings or structures, or on decks or under eaves, canopies of other projections, or overhangs. Storage of firewood and combustible material stored in the defensible space must be located a minimum of 15 feet from structures and separated from the driplines of trees by a minimum of 15 feet. Roofs: All roofs of structures in designated wildland fire hazard areas shall comply with the following guidelines: ✓ Remove leaves, needles, twigs, and other combustible matter from roofs and rain gutters. ✓ Portions of trees which extend within 10 feet of the outlet of a chimney shall be removed. ✓ All chimneys attached to any appliance or fireplace that burns solid fuel shall be equipped with an approved spark arrester. The spark arrester screen shall be made from a material that is both heat and corrosion resistant, and the openings shall not permit the passage of spheres having a diameter larger that 1/2- inch. • In some areas of Newport Beach, and specifically in Newport Coast, neighborhoods are required to comply with fuel modification requirements. These requirements are imposed when a new community or development is proposed adjacent to a wildland area. Any project in or adjoining a wildland fire hazard area is required to submit a Fire Protection Plan for review and approval before a grading or building permit for new construction is issued. These plans need to meet the criteria of the Newport Beach Fire Department's Fuel Modification Plan and Maintenance Guidelines (Section 9.04.030 of the City of Newport Beach Municipal Code). The areas with approved and preliminary fuel modification plans are shown on Plate 5-4. This map should be updated as the preliminary fuel modification zones are approved, or new plans are developed for those areas that currently have no plans in place. In Newport Coast, the Orange County Fire Authority has the responsibility for reviewing and approving fuel modification zones and the inspection of the installation of these zones. The City of Newport Beach has the responsibility of ensuring that these areas are maintained in accordance with the Fire Protection Plan approved by the Orange County Fire Authority. Fire Protection Plans need to show the following: ✓ all existing and proposed private and public streets on the property proposed for development, and within 300 feet of the property line, ✓ the locations of all existing and proposed fire hydrants within 300 feet of the property line, and ✓ the location, occupancy classification and use of structures and buildings on the Earth Consultants International Fire Hazards Page 5-11 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA 40 properties abutting the proposed development. A fuel modification zone is a ribbon of land surrounding a development within a fire hazardous area that is designed to diminish the intensity of a wildfire as it approaches the structures. Fuel modification includes both the thinning (reducing the amount) of native combustible vegetation, and the removal and replacement of native vegetation with fire - resistive plant species. The minimum width of a fuel modification zone is 170 feet. These areas may be owned by individual property owners or by a homeowners' association. In the case of Newport Coast, local homeowners' associations own the majority of the fuel modification areas. Emphasis is placed on the space near structures that provides natural landscape compatibility with wildlife, water conservation and ecosystem health. Immediate benefits of this approach include improved aesthetics, increased health of large remaining trees and other valued plants, and enhanced wildlife habitat. The fuel modification zone is typically divided into four areas referred to as the A, B, C and D zones. The A Zone is the closest to the homes, and is the last 20-feet of the backyard of the private residences. The B, C and D zones lie outside the fence line and are within the common area typically owned by an association. Any dead or dying vegetation shall be removed from all zones, and certain fire -prone species of vegetation are required to be removed when found in any of the four fuel modification zones. Each of these zones is described further below and shown graphically on Figures 5-3 and 5-4. • The A Zone is the defensible space where firefighters will set up hose lines to extinguish the approaching fire. The A zone includes ornamental plants and single specimen trees. All plants in this area are required to be irrigated and must be from the City -approved plant list. The B Zone is the next 50 feet just outside the back fence line. This zone is an area where natural vegetation has been replaced with fire -resistive, drought -tolerant plants from the City -approved Fire Resistive Plant list. The B zone is fitted with automatic water sprinklers on a permanent basis. Non -approved vegetation must be removed from this zone. The C and D zones are the next 100 feet away from the homes. Each of these zones is a minimum of 50 feet in width. These zones are called the thinning zones. Natural vegetation is reduced by 50 percent in the C zone, and by 30 percent in the D zone. A way to imagine this thinning principle is as follows: in the 50 percent thinning zone (C zone) two people can walk side by side around clumps of vegetation. In a 30 percent thinning zone (D Zone), two people would have to walk single file between clumps of natural vegetation. These areas are not irrigated. In addition to reduction of the vegetation hazards, areas regulated by the City's fuel modification requirements also have to "harden" the structures immediately adjacent to the wildland area by providing automatic fire sprinkler protection, installation of class "A" roof assemblies, installation of dual glazed windows, one -hour fire resistive construction on the • sides of the structures facing the wildland area, and the elimination of combustible exterior Earth Consultants International Fire Hazards Page 5-12 2003 • 1J HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA structural elements (such as patio covers). These structural requirements are discussed further in Section 5.1.3.4, below. Figure 5-3: Fuel Modification Zones Required in Fire Hazardous Areas in Newport Coast Property Line Top of Slope A B Zone „Zone C Zone D Zone Irrigated MAINTAINED BY HOMEOWNERS' ASSOCIATION Building Setback should be sufficient to accommodate patio covers, gazebos, etc. /X000` Newport Beach Home MAINTAINED BY HOMEOWNER The guidelines adopted by Newport Beach for vegetation management in defensible areas are designed to be a fire prevention partnership between property owners and the City in order to prevent disastrous fires. The ordinance is designed to minimize fire danger by controlling density and placement of flammable vegetation. It does not recommend indiscriminate clearing of native coastal sage scrub and other types of plants that perform important roles in erosion control. The mitigation measures provided herein are the minimum required standards. In some high fire hazard areas or during certain times of the year, when due to the hot, dry weather there is an increased risk of wildfires, the Fire Marshal may determine that conditions warrant greater fire protection measures than what the minimum standards provide for- In that event, the Fire Marshal has the authority to supercede the requirements described above. Earth Consultants International Fire Hazards 2003 Page 5-13 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Figure 5-4: Example of Vegetation Management at the Urban-Wildland Interface. (Residential community in Newport Beach that uses fuel modification to reduce its fire hazard. Note selective thinning of vegetation in the slope below the structures (C and D Zones). Closer to the structures, there is a zone of fire -resistive plants that are irrigated (Zone B). The vegetation in the foreground is in its natural state.) • 5.1.3.2 Erciusions to Special Fire Protection Areas According to the City's Municipal Code (Section 9.04.410, Sections 7 through 12), a property originally located in a Special Fire Protection Area may be excluded (or removed) from the SFPA and placed in the Conditional Exclusions Zone if the property owner or homeowners' association can show to the satisfaction of the Orange County Fire Authority's Chief that they are in compliance with the following requirements: ✓ a Fuel Modification Zone adjoining the property has been created and is maintained; ✓ if the Fuel Modification Zone is maintained by a homeowners' association, the homeowners' association collects from the property owners specifically budgeted funds to conduct the maintenance obligations associated with the fuel modification requirements; ✓ the Fuel Modification Zone is inspected annually by a City representative to assure that the Fuel Modification Zone is being maintained appropriately; ✓ any occupied structure on any lot adjacent to a Special Fire Protection Area is constructed in compliance with all requirements of the Uniform Building Code and the Uniform Fire Code applicable to dwellings or occupied structures on lots within Special Fire Protection Areas; ✓ all construction within a tract excluded from a Special Fire Protection Area utilizes Class A roof assemblies. The Conditional and Total Exclusion zones approved by the Orange County Fire Authority and adopted by Newport Beach are shown on Plate 5-3. • Earth Consultants International Fire Hazards Page 5-14 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 5.1.3.3 Notification and Abatement City Code specifies that property owners are required to mitigate the fire hazard in their property by implementing the vegetation management practices discussed above. Therefore, if uncontrolled or high weeds, brush, plant material, or other items prohibited under the City's Municipal Code are present in a property, the Fire Marshal has the authority to give the property owner of record a notice to abate the hazard. The property owner has 30 days to comply. If the owner does not abate the hazard during the time period specified in the notice, the City may take further action to reduce the fire hazard. Further action may include the following: ✓ The City or its contractor may enter the parcel of land and remove or otherwise eliminate or abate the hazard; ✓ upon completion of the work, the City can bill the property owner for the cost of the work plus any administrative costs, or the cost can become a special assessment against that parcel; and ✓ upon City Council confirmation of the assessment and recordation of that order, a lien may be attached to the parcel, to be collected on the next regular property tax bill levied against the parcel. The Fire Marshal has to notify the property owner of the intention to abate the fire hazard by certified mail. The notices have to be mailed at least 15 days prior to the date of the proposed abatement. The property owner may appeal the decision of the Fire Marshal • requiring the maintenance of an effective firebreak by sending a written appeal to the Fire Chief within 10 days of the notice. For additional information regarding the Notification and Abatement procedures, refer to Section 16.6 of the City's Municipal Code. 5.1.3.4 Building to Reduce the Fire Hazard Building construction standards for such items as roof coverings, fire doors, and fire resistant materials help protect structures from external fires and contain internal fires for longer periods. That portion of a structure most susceptible to ignition from a wildland fire is the roof, due to the deposition of burning cinders or brands. Burning brands are often deposited far in advance of the actual fire by winds. Roofs can also be ignited by direct contact with burning trees and large shrubs (Fisher, 1995). The danger of combustible wood roofs, such as wooden shingles and shakes, has been known to fire fighting professionals since 1923, when California's first major urban fire disaster occurred in Berkeley. It was not until 1988, however, that California was able to pass legislation calling for, at a minimum, Class C roofing in fire hazard areas. Then, in the early 1990s, there were several other major fires, including the Paint fire of 1990 in Santa Barbara, the 1991 Tunnel fire in Oakland/Berkeley, and the 1993 Laguna Beach fire, whose severe losses were attributed in great measure to the large percentage of combustible roofs in the affected areas. In 1995-1996, new roofing materials standards were approved by California for Very High Fire Hazard Severity Zones. To help consumers determine the fire resistance of the roofing materials they may be considering, roofing materials are rated as to their fire resistance into three categories that • are based on the results of test fire conditions that these materials are subjected to under rigorous laboratory conditions, in accordance with test method ASTM-E-108 developed by Earth Consultants International Fire Hazards Page 5-15 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • the American Society of Testing Materials. The rating classification provides information regarding the capacity of the roofing material to resist a fire that develops outside the building on which the roofing material is installed (The Institute for Local Self Government, 1992). The three ratings are as follows: Class A: Roof coverings that are effective against severe fire exposures. Under such exposures, roof coverings of this class: Are not readily flammable; Afford a high degree of fire protection to the roof deck; Do not slip from position; and Do not produce flying brands. Class B: Roof coverings that are effective against moderate fire exposures. Under such exposures, roof coverings of this class: Are not readily flammable; Afford a moderate degree of fire protection to the roof deck; Do not slip from position; and Do not produce flying brands. Class C: Roof coverings that are effective against light fire exposures. Under such exposures, roof coverings of this class: Are not readily flammable; Afford a measurable degree of fire protection to the roof deck; • Do not slip from position; and Do not produce flying brands. Non -Rated Roof coverings have not been tested for protection against fire exposure. Under such exposures, non -rated roof coverings: May be readily flammable; May offer little or no protection to the roof deck, allowing fire to penetrate into attic space and the entire building; and May pose a serious fire brand hazard, producing brands that could ignite other structures a considerable distance away. In 1992, the City of Newport Beach required roofing materials to be at a minimum Class C VJ (The Institute for Local Self Government, 1992). This is still the case in most areas of the City, with the exceptions noted below. As of the writing of this document, however, a revision to the City's Building Code that may include stricter roofing material requirements was being proposed. In Special Fire Protection Areas, including those in the City of Newport Beach as shown on Plate 5-3, new construction and reconstruction are required to have, as a minimum, Class A roofing assemblies (Section 6.6 of Appendix II-A-2 of the California Fire Code). Any repairs and additions that amount to ten percent or more of the existing roof area are also required to be Class A roof assemblies. Attic ventilation openings are also a concern regarding the fire survivability of a structure. Attics require significant amounts of cross -ventilation to prevent the degradation of wood • rafters and ceiling joists. This ventilation is typically provided by openings to the outside of the structure, but these opening can provide pathways for burning brands and flames to Earth Consultants International Fire Hazards Page 5-16 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA be deposited within the attic. Therefore, it is important that all ventilation openings be properly screened to prevent this. In the Special Fire Protection Areas in the City of Newport Beach, attic or foundation ventilation openings in vertical walls and attic roof vents cannot be more than 144 square inches in size, and these need to be covered with metal louvers and 1/4-inch mesh corrosion -resistant metal screens. Furthermore, ventilation openings and access doors are not permitted on the exposed side of the structure. For more specific information refer to Section 6 — Building Construction Features of Section 9.04.410 of the City's Municipal Code, and Appendix II-A-2 of the California Fire Code). Additional prevention measures that can be taken to reduce the potential for ignition of attic spaces is to "use non-combustible exterior siding materials and to site trees and shrubs far enough away from the walls of the house to prevent flame travel into the attic even if a tree or shrub does torch" (Fisher, 1995). The type of exterior wall construction used can also help a structure survive a fire. Ideally, exterior walls should be made of non-combustible materials such as stucco or masonry. During a wildfire, the dangerous active burning at a given location typically lasts about 5 to 10 minutes (Fisher, 1995), so if the exterior walls are made of non-combustible or fire-resistant materials, the structure has a better chance of surviving. For the same reason, the type of windows used in a structure can also help reduce the potential for fire to impact a structure. Single -pane, annealed glass windows are known for not performing well during fires; thermal radiation and direct contact with flames cause these windows to break because the glass under the window frame is protected and remains cooler than the glass in the center of the window. This differential thermal expansion of the glass causes • the window to break. Larger windows are more susceptible to fracturing when exposed to high heat than smaller windows. Multiple -pane windows, and tempered glass windows perform much better than single -pane windows, although they do cost more. Fisher 0 995) indicates that in Australia, researchers have noticed that the use of metal screens helps protect windows from thermal radiation. The City of Newport Beach has construction requirements for cornices, eaves, overhangs, soffits, and exterior balconies in Special Fire Protection Areas. According to the City's Municipal Code, these need to be made of non-combustible construction materials, enclosed in one -hour fire -resistive material, or made of heavy timber construction. Space between rafters at the roof overhangs need to be protected by non-combustible materials or protected by double 2-inch nominal solid blocking under the exterior wall covering. Ventilation openings or other types of openings are not permitted in eave overhangs, soffits, between rafters at eaves, or in other overhanging areas on the exposed side of the structure (Section 6 — Building Construction Features of Section 9.04.410 of the City's Municipal Code). 5.1.3.5 Restricted Public Access Although not apparent from the figures included in this report (such as Plates 5-2 and 5-3), in reality, the wildfire susceptibility of an area changes throughout the year, and from one year to the next in response to local variations in precipitation, temperature, vegetation growth, and other conditions. Therefore, since the early 1990's, the EROS Data Center (EDC) in Sioux Falls, South Dakota, has produced weekly and biweekly maps for the 48 • contiguous states and Alaska. These maps, prepared under the Greenness Mapping Project, display plant growth and vigor, vegetation cover, and biomass production, using Earth Consultants International Fire Hazards Page 5-17 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . multi -spectral data from satellites of the National Oceanic and Atmospheric Administration (NOAA). The EDC also produces maps that relate vegetation conditions for the current two weeks to the average (normal) two -week conditions during the past seven years. EDC maps provide comprehensive growing season profiles for woodlands, rangelands, grasslands, and agricultural areas. With these maps, fire departments and land managers can assess the condition of all vegetation throughout the growing season, which improves planning for fire suppression, scheduling of prescribed burns, and study of long-term vegetation changes resulting from human or natural factors. Another valuable fire management tool developed jointly by the US Geological Survey and the US Forest Service is the Fire Potential Index (FPI). The FPI characterizes relative fire potential for woodlands, rangelands, and grasslands, both at the regional and local scale. The index combines multi -spectral satellite data from NOAA with geographic information system (GIS) technology to generate 1-km resolution fire potential maps. Input data include the total amount of burnable plant material (fuel load) derived from vegetation maps, the water content of the dead vegetation, and the fraction of the total fuel load that is live vegetation. The proportion of living plants is derived from the greenness maps described above. Water content of dead vegetation is calculated from temperature, relative humidity, cloud cover, and precipitation. The FPI is updated daily to reflect changing weather conditions. Local fire authorities can obtain data from either of the two sources above to better prepare for the fire season. When the fire danger in a High Fire Hazard Zone is deemed to be of . special concern, local authorities can rely on increased media coverage and public announcements to educate the local population about being fire safe. For example, to reduce the potential for wildfires during fire season in the unincorporated areas of Orange County and in some cities, such as Orange, Anaheim, Brea and Laguna Beach, the Orange County Fire Authority (OCFA) closes hazardous fire areas to public access during at least part of the year. Typically, the fire season in Orange County begins in mid April and lasts until the first rains. With more site -specific data obtained from the FPI or Greenness Mapping Project, however, the fire hazard of an area could be assessed on a weekly or bi- weekly basis. These data can also be used to establish regional prevention priorities that can help reduce the risk of wildland fire ignition and spread, and help improve the allocation of suppression forces and resources, which can lead to faster control of fires in areas of high concern. Restricted public access to preserves and parks in and around the eastern part of the City of Newport Beach during the fire season can help limit the opportunity for man -caused fires to develop. Continued use of signs during high and extreme fire conditions along the freeways and toll roads that cut through the wildland areas in the eastern portion of the City and adjacent areas can also help reduce the fire hazard by alerting and educating motorists about the potential fire hazard in the area. 5.1.3.6 Real -Estate Disclosure Requirements California state law requires that fire hazard areas be disclosed in real estate transactions; that is, real-estate sellers are required to inform prospective buyers whether or not a • property is located within a wildland area that could contain substantial fire risks and hazards [Assembly Bill 6; Civil Code Section 1103(c)(6)]. Current Real Estate disclosure Earth Consultants International Fire Hazards Page 5-18 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • requirements ask two "yes or no" questions concerning fire hazards. The questions are formatted as follows: THIS REAL PROPERTY LIES WITHIN THE FOLLOWING HAZARDOUS AREA(S): A VERY HIGH FIRE HAZARD SEVERITY ZONE pursuant to Section 51178 or 51179 of the Government Code. (The owner of this property is subject to the maintenance requirements of Section 51182 of the Government Code.) (Note that the Special Fire Protection Areas in the City of Newport Beach are equivalent to the State's Very High Fire Hazard Severity Zones.) A WILDLAND AREA THAT MAY CONTAIN SUBSTANTIAL FOREST FIRE RISKS AND HAZARDS pursuant to Section 4125 of the Public Resources Code. (The owner of this property is subject to the maintenance requirements of Section 4291 of the Public Resources Code. Additionally, it is not the State's responsibility to provide fire protection services to any building or structure located within the wildlands unless the Department of Forestry and Fire Protection has entered into a cooperative agreement with a local agency for those purposes pursuant to Public Resources Code Section 4142.) Real-estate disclosure requirements are important because in California the average period of ownership for residences is only five years (Coleman, 1994). This turnover creates an information gap between the several generations of homeowners in fire hazard areas. Un- informed homeowners may attempt landscaping or structural modifications that could be a detriment to the fire-resistant qualities of the structure, with negative consequences. 5.1.3.7 Fire Safety Education Individuals can make an enormous contribution to fire hazard reduction and need to be educated about their important role. In addition to the specific requirements in the Code mentioned in the sections above regarding defensible space, appropriate landscaping and construction materials, there are other tasks that homeowners can take to reduce the risk of fire in their property. Some of these tasks are listed below. This list is not all-inclusive, but provides a starting point and framework to work from. Mow and irrigate your lawn regularly. Dispose of cuttings and debris promptly, according to local regulations. Store firewood away from the house. Be sure the irrigation system is well maintained. Use care when refueling garden equipment and maintain it regularly. Store and use flammable liquids properly. Dispose of smoking materials carefully. Do not light fireworks (Municipal Code prohibits fireworks). Become familiar with local regulations regarding vegetation clearings, disposal of debris, and fire safety requirements for equipment. • Follow manufacturers' instructions when using fertilizers and pesticides. Earth Consultants International Fire Hazards Page 5-19 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • When building, selecting or maintaining a home, consider the slope of the terrain. Be sure to build on the most level portion of the lot, since fire spreads rapidly on slopes, even minor ones. Watch out for construction on ridges and cliffs. Keep a single -story structure at least 30 feet away from edges; increase distance if structure exceeds one story. Use construction materials that are fire-resistant or non-combustible whenever possible. For roof construction, recommended materials are Class -A asphalt shingles, slate or clay tile, metal, cement and concrete products, or terra-cotta tiles. Constructing a fire-resistant sub -roof can add protection. On exterior wall cladding, fire -resistive materials such as stucco or masonry are much better than vinyl, which can soften and melt. A driveway should provide easy access for fire engines. Roadway requirements for fire equipment are described later in this report. The driveway and access roads should be well maintained, clearly marked, and include ample turnaround space near the house. So that everyone has a way out, provide at least two ground level doors for safety exits and at least two means of escape (doors or windows) — in each room. Keep gutters, eaves, and roof clear of leaves and other debris. Occasionally inspect your home, looking for deterioration, such as breaks and spaces between roof tiles, warping wood, or cracks and crevices in the structure. If an all -wood fence is attached to your home, a masonry or metal protective barrier between the fence and house is recommended. Use non-flammable metal when constructing a trellis and cover it with high -moisture, non-flammable vegetation. Prevent combustible materials and debris from accumulating beneath patio decks or elevated porches. Screen, or box in, areas that lie below ground level with wire mesh. Make sure an elevated wooden deck is not located at the top of a hill where it will be in the direct line of a fire moving up slope. Install automatic seismic shut-off valves for the main gas line to your house. Information for approved devices, as well as installation procedures, is available from the Southern California Gas Company. 5.1.3.8 Other Fire Hazard Reduction Techniques Before European settlers arrived, many areas of the United States experienced small but frequent wildfires that impacted primarily the grasses and low-lying bushes, without severely damaging the tree stands. Native Americans in California reportedly used fire to reduce fuel load and improve their ability to hunt and forage. It is thought that as much as 12 percent of the State was burned every year by various tribes (Coleman, 1994). However, in the early 201h Century, as development started to encroach onto the foothills, wildfires came to be unacceptable, and in the early 1920s, the Fire Service began campaigns to prevent wildfires from occurring. Unfortunately, over time, this has led to an increase in fuel loads. This is significant because wildfires that impact areas with fuel buildup are more intense and significantly more damaging to the ecosystem than periodic, low -intensity fires. Earth Consultants International Fire Hazards Page 5-20 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Over time, fire suppression and increasing populations have produced these results: Increased losses to life, property, and resources; Increased difficulty in suppressing fires, increased safety problems for firefighters, and reduced productivity by fire crews on perimeter lines; Longer periods between recurring fires; Increased volume of fuel per acre; and Increased taxpayer costs and property losses. Recognition of these problems has led to vegetation management programs such as those described above, and in some areas, prescribed fires. A prescribed fire is deliberately set under carefully controlled and monitored conditions. The purpose is to remove brush and other undergrowth that can fuel uncontrolled fires. Prescribed fire is used to alter, maintain or restore vegetative communities, achieve desired resource conditions, and to protect life and property that would be degraded by wildland fire. Prescribed fire is only accomplished through managed ignition and should be supported by planning documents and appropriate environmental analyses. Since 1981, prescribed fire has been the primary means of fuel management in Federal and State-owned lands. Approximately 500,000 acres — an average of 30,000 acres a year — have been treated with prescribed fire under the vegetation management program throughout the State. In the past, the typical vegetation management project targeted large • wildland areas. Now, increasing development pressures (with increased populations) at the urban-wildland interface often preclude the use of large prescribed fires. Nevertheless, many still find the notion of "prescribed fire" difficult to accept given that it goes against nearly 100 years of common practice and beliefs. Prescribed fire does carry a risk, as recent experiences in New Mexico and Arizona have shown. The Cerro Grande fire began when a prescribed burn escaped, destroying several hundred homes in Los Alamos, New Mexico and burning more than 50,000 acres. It is likely that this fire will lead to revisions in the guidelines for performing prescribed burns. Furthermore, a recent program review by the California Department of Forestry and Fire Prevention (CDF) has identified needed changes, with focus on citizen and firefighter safety, and the creation of wildfire safety and protection zones. Prescribed fire is not presently being used in the City of Newport Beach to mitigate the VJ wildland fire hazard. Some communities like Laguna Beach have opted for other methods of vegetation management, namely, the use of goats to keep the vegetation in check. In Laguna Beach, this program appears to be working, and is also popular with residents, who generally enjoy the pastoral scenes provided by the goats grazing on the hillsides. Nevertheless, the environmental impacts of goat herding need to be evaluated over time to determine whether or not this is an environmentally sensitive solution. Some issues to consider, for example, is that if indeed, some plant species endemic to the area will not reproduce unless aided by fire, then the use of prescribed fire as a management tool may be reconsidered. • 5.1.4 Post -Fire Effects Fires usually last only a few hours or days, but their effects can last much longer, especially Earth Consultants International Fire Hazards Page 5-21 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • in the case of intense fires that develop in areas where large amounts of dry, combustible vegetation have been allowed to accumulate. If wildland fires are followed by a period of intense rainfall, debris flows off the recently burned hillsides can develop. Flood control facilities may he severely taxed by the increased flow from the denuded hillsides and the resulting debris that washes down. If the flood control structures are overwhelmed, widespread damage can ensue in areas down gradient from these failed structures. • However, this does not need to happen if remedial measures following a wildfire are taken in anticipation of the next winter. Studies (Cannon, 2001) suggest that in addition to rainfall and slope steepness, other factors that contribute to the formation of post -fire debris flows include the underlying rock type, the shape of the drainage basin, and the presence or absence of water -repellant soils (during a fire, the organic material in the soil may be burned away or decompose into water-repellent substances that prevents water from percolating into the soil.) Figure 5-5: Photograph Showing Denudation of Slopes Following the 1993 Laguna Beach Fire. Sandbags, plastic covers and other measures were implemented as soon as possible to reduce the potential for slope instability during the winter following the fire. Other effects of wildfires are economical and social. Homeowners who lose their house to a wildfire may not be able to recover financially and emotionally for years to come. Recreational areas that have been affected may be forced to close or operate at a reduced scale. In addition, the buildings that are destroyed by fire are usually eligible for re- assessment, which reduces income to local governments from property taxes. The impact of wildland fire on plant communities is generally beneficial, although it often takes time for plant communities to re-establish themselves. If a grassland area has been burned, it will re -sprout the following spring. Coastal sage scrub and chaparral plant communities will take three to five years. Oak woodland, if it has had most of the Earth Consultants International Fire Hazards Page 5-22 2003 • • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA seedlings and saplings destroyed by fire, will require at least five to ten years for a new crop to start. 5.2 Structural Fires In order to quantify the structural fire risk in a community, it is necessary for the local fire departments to evaluate all occupancies based upon their type, size, construction type, built-in protection (such as internal fire sprinkler systems) and risk (high -occupancy versus low -occupancy) to assess whether or not they are capable of controlling a fire in the occupancy types identified. Simply developing an inventory of the number of structures present within a fire station's response area is not sufficient, as those numbers do not convey all the information necessary to address the community's fire survivability. In newer residential areas where construction includes fire-resistant materials and internal fire sprinklers, most structural fires can be confined to the building or property of origin. In older residential areas where the building materials may not be fire -rated, and the structures are not fitted with fire sprinklers, there is a higher probability of a structural fire impacting adjacent structures, unless there is ample distance between structures, there are no strong winds, and the Fire Department is able to respond in a timely manner. As discussed in detail below, in some areas of Newport Beach older structures abut each other, increasing the probability of a structural fire not being confined only to its building of origin. The previous section described in detail the wildfire risk in the City. Review of the maps provided would suggest that the western, extensively developed portion of Newport Beach does not have a fire hazard, but this is not so — it is just not a wildfire hazard. The small- town character that makes several of the older portions of the City, including Balboa Peninsula, Balboa Island and Corona del Mar, so appealing to residents and tourists alike, also puts these areas at risk from structural fires. Many of the structures in these areas are of older vintage, some dating back to the 1930s, built to older building standards and fire codes, made from non -fire resistive construction materials, and with no internal sprinklers and other fire safety systems in place. The density of construction in these areas is also an issue. Residences are close to each other, generally with only 3-foot setbacks (4-foot setbacks in Corona del Mar) between the (t—j houses and the property lines, and projections (such as window and roof awnings) into this t- 3-foot area are allowed. These projections into the 3-foot setback hinder emergency access to the back of residences (see Figure 5-6), and should therefore be discouraged or prohibited. The narrow streets in these areas of the City also make it difficult to maneuver and position response vehicles so as to be most effective in fighting a fire, and have the potential to severely constrain efforts to evacuate the area if necessary during a fire or other disaster. The City's permanent residential population is currently about 75,660, but this number does not include the thousands that come into Newport Beach daily to work, dine or shop. On weekends, and during the summer, because of the City's tourist draw, the population in the City may swell to well over 200,000. A large percentage of these visitors park their vehicles and visit in the older sections of town, adding to the congestion and difficulty of ingress and egress of emergency response vehicles. . Geography is also at odds with fire safety in the City. Upper and Lower Newport Bay essentially divide the City into two regions, with approximately one-third of the Fire Department assets located west of the bay, and the remaining assets east of the bay (see Earth Consultants International Fire Hazards Page 5-23 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Plate 5-2). Connection between these two sides is provided by only a handful of roadways (Pacific Coast Highway in the south, Bristol Street and the 73 Freeway on the north), making it difficult for fire stations on both sides of the bay to support each other during multiple alarm emergencies. Often, it best to request support from adjacent cities via mutual aid agreements than to have Newport Beach fire stations from the other side of the bay send in reinforcements. Catastrophic failure of the bridge connectors on any of these roadways as a result of an earthquake, for example, would hinder emergency response from fire stations in east Newport Beach and Newport Coast into the densely populated areas of the City west and south of the bay. • Figure 5-6: Newport Beach Fire Department personnel illustrating the difficulty of maneuvering emergency equipment and victims through the 3-foot allowable building setback, especially if non-structural additions project into this area. Dumpsters and other things stored in this area can also make access to the back of a residence difficult, if not impossible. Residents should maintain this area free of obstructions. 5.2.1 Structural Target Fire Hazards and Standards of Coverage Fire departments quantify and classify structural fire risks to determine where a fire resulting in large losses of life or property is more likely to occur. The structures at risk are catalogued utilizing the following criteria: The size, height, location and type of occupancy; The risk presented by the occupancy (probability of a fire and the consequence if one occurs); The unique hazards presented by the occupancy (such as the occupant load, the types of combustibles therein and any hazardous materials); • Earth Consultants International Fire Hazards Page 5-24 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Potential for loss of life; The presence of fire sprinklers and proper construction; Proximity to exposures; The estimated dollar value of the occupancy; The needed fire flow versus available fire flow; and The ability of the on -duty forces to control a fire therein. These occupancies are called "Target Hazards." Target Hazards encompass all significant community structural fire risk inventories. Typically, fire departments identify the major target hazards and then perform intensive pre -fire planning, inspections and training to address the specific fire problems in that particular type of occupancy (for example, training to respond to fires in facilities that handle hazardous materials is significantly different than training to respond to a fire in a high -occupancy facility such as a mall, auditorium or night club). Typically, the most common target hazard due to the life -loss potential, 24-hour occupancy, risk and frequency of events, is the residential occupancy, however, the consequences of residential fires can be high or low, depending on the age, location, size, and occupancy load, among other factors. Four classifications of risk are considered, as follows: High Probability/High consequences (Example: multi -family dwellings and residential high-rise buildings, single-family residential homes in the older sections of the City such as Balboa Island, Balboa Peninsula and Corona del Mar, hazardous materials occupancies (see Chapter 6), and large shopping centers such as Fashion • Island). Low Probability/High consequences (Example: Hoag Memorial hospital and other medical facilities, mid -size shopping malls, industrial occupancies, large office complexes and new upscale homes in the high hazard vegetation areas). High Probability/Low consequences (Example: older detached single-family dwellings in the non -vegetated areas of town). Low Probability/Low Consequences (Example: newer detached single-family dwellings in non -vegetated areas and small office buildings). In order to address the Fire Department's capability to respond effectively to the structural fire risk in Newport Beach, "Standards of Coverage" need to be determined based upon the various risks. Those risks are: Single-family detached residential, multi -family attached residential, commercial and industrial. Some of these risks exist in various areas throughout the City, rather than in well-defined separate areas. For example, residential areas adjoining, and intermixed with, commercial areas occur especially in the older portions of the City on Balboa Peninsula, Balboa Island, and Corona del Mar. Given these combined risks within the same geographic area, it is appropriate for the Newport Beach Fire Department to have several fire stations within the older, intensely developed portion of the City. For the location and distribution of fire stations in the City of Newport Beach, refer to Plates 5-2, 5-3 and 5-5. Some of the high probability/high consequence risks that fire departments worry the most are high-rise buildings due to the specialized fire -fighting equipment needed, the limited • routes of access into and out of a building, and the potential for great loss of life. Newport Beach has over 30 high-rise buildings that were constructed since the 1960s. [A high-rise Earth Consultants International Fire Hazards Page 5-25 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • in the City is defined as any building with floors used for human occupancy that are located more than 55 feet (16.76 m) above the lowest level of fire department access.] High-rise buildings are now required to have several redundant fire and life safety systems in place, including automatic fire sprinklers and fire alarm detectors (Municipal Code Section 9.04.130). However, there are three older residential high-rise buildings in the City that are not sprinklered. These buildings are located at: 3121 West Coast Highway 601 Lido Park Drive, and 611 Lido Park Drive The property owners of these buildings should be encouraged to retrofit their structures to include internal fire sprinklers. 5.2.2 Model Ordinances and Fire Codes Effective fire protection cannot be accomplished solely through the acquisition of equipment, personnel and training. The area's infrastructure also must be considered, including adequacy of nearby water supplies, transport routes and access for fire equipment, addresses, and street signs, as well as maintenance. The City of Newport Beach has adopted the 2001 California Fire Code with City amendments and some exceptions (City Ordinance 2002-19 § 1 (part), 2002). The City's Fire Chief is authorized and directed to enforce the provisions of the Municipal Code throughout the City. • These provisions include constructions standards in new structures and remodels, road widths and configurations designed to accommodate the passage of fire trucks and engines, and requirements for minimum fire flow rates for water mains. The construction requirements are a function of building size, type, material, purpose, location, proximity to other structures, and the type of fire suppression systems installed. For building construction standards in the City of Newport Beach refer to the City's Municipal Code. The City of Newport Beach road standards for fire equipment access are summarized in Table 5-1. For more specific information, refer to Section 9.04.060 of the City's Municipal Code. r 1 U Some of the more significant Municipal Code items that help reduce the hazard of structural fire in the City include requirements regarding fire sprinklers (Municipal Code Section 9.04.090). The City has been requiring fire sprinklers in all structures more than 5,000 square feet in area since 1987, and therefore all post-1987 structures more than 5,000 square feet in area have this fire safety feature. Fire sprinklers can help contain a fire that starts inside a structure from spreading to other nearby structures, and also help prevent total destruction of a building. If additions to a structure cause it to exceed the 5,000 square foot area, one of the three following conditions apply: 1. When such additions are 25 percent or less than the original building square footage, the existing structure, and the addition need not be equipped with an automatic sprinkler system. Earth Consultants International Fire Hazards Page 5-26 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 2. When such additions exceed 25 percent but are less than 50 percent of the original building square footage, the addition shall be equipped with an automatic sprinkler system. • 3. When such additions are 50 percent or more of the original building square footage, the entire structure shall be equipped with an automatic sprinkler system throughout. Table 5-1: Road Standards for Fire Equipment Access Width of Fire Lanes 20 feet wide, no less than 26 feet within 30 feet of a fire hydrant, 28 feet in Special Fire Protection Areas. Grades Not to exceed 10 percent. Turning Radius No less than 20 feet inside radius and 40 feet outside radius, without parking. Cul-de-sacs with center obstructions require larger radii as approved by the Fire Chief. Gates Minimum width of any gate or opening required as a point of access shall be no less than 20 feet Based on the length of the approach, this width may have to be larger. If there are separate gates for each direction of travel, then each gate shall be no less than 14 feet wide. Any point of access deemed necessary for emergency response shall remain unobstructed at all times. All primary access points, if gated, must be electronically operated and controlled by an approved key switch and strobe light receiver. Any secondary access points shall have a lock approved by the Newport Beach Fire Department Electrically operated gates require an approved key switch and strobe light receiver. Signage All premises need to be identified with approved numbers or addresses in a position plainly visible and legible from the streetor road fronting the property. Refer to Section 9.04.060 of the City's Municipal Code for specifics on the minimum size of the letters and numbers. Other Requirements A minimum of 2 fire apparatus access roads shall be provided in for Fire Access residential units containing 25 or more dwellings. Roadways Speed bumps, speed humps or any obstructions in required fire access roadways are prohibited. For structures more than 5,000 square feet in area that pre -date the 1987 Code requirements and are therefore not equipped with fire sprinklers, the following conditions apply if and when the building is added on to: 1. When additions are 1,250 square feet or less, the existing structure and the addition need not be equipped with an automatic sprinkler system. 2. When additions exceed 1,250 square feet but are less than 2,500 square feet, the addition shall be equipped with an automatic sprinkler system. 3. When additions are 2,500 square feet or more, the entire structure shall be equipped with an automatic sprinkler system throughout • Earth Consultants International Fire Hazards Page 5-27 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The City's Municipal Code also states that in partially sprinklered buildings, sprinklered areas shall be separated from non-sprinklered areas, and such separation shall not be less than that required for a one -hour occupancy separation. Other Municipal Code requirements that help reduce the fire hazard in structures include fire sprinkler monitoring systems that transmit a signal to a remote, continuously attended station (Municipal Code Section 9.04.100); hose outlets and exterior access doors in all new buildings with horizontal dimensions (width or length) greater than 300 feet so that all parts of the building can be reached with 150 feet of hose from an access door or hose outlet (Section 9.04.110); and smoke detectors and smoke detection systems (Section 9.04.80). The City also prohibits the use, sale, possession or handling of fireworks anywhere in the City, unless the fireworks are part of a permitted public display conducted by a licensed pyrotechnic operator (Sections 9.04.220 and 9.04.230). Fire Flow is the flow rate of water supply (measured in gallons per minute — gpm) available for fire fighting measured at 20 pounds per square inch (psi) residual pressure. Available fire flow is the total water flow available at the fire hydrants, also measured in gallons per minute. As of the writing of this report, Newport Beach had adopted the section of the 2001 California Fire Code that lists the minimum required fire -flow and flow duration for buildings of different floor areas and construction types (Appendix III -A). For additional information regarding the required fire -flow for your building, contact the City's Fire • Department. Do note that, consistent with the California Fire Code, the Newport Beach Municipal Code indicates that in buildings fitted with approved internal automatic sprinkler systems, the minimum require fire flow for that structure may be reduced by up to 50 percent, as approved by the Fire Chief, but the resulting fire flow cannot be less than 1,500 gallons per minute (Section 9.04.450 of the Municipal Code). Local water districts are required to test their fire protection capability for the various land uses per the flow requirements of the California Fire Code. Emergency water storage is critical, especially when battling large wildland fires. During the 1993 Laguna Beach fire, "water streams sprayed on burning houses sometimes fell to a trickle" (Orange County Fire Department, 1994), primarily because most water reservoirs in Laguna were located at lower elevations, and the water district could not supply water to the higher elevations as fast as the fire engines were using it. 'Leaks and breaks in the water distribution system, including leaking irrigation lines and open valves in destroyed homes also reduced the amount of water available to the fire fighters. A seven-day emergency storage supply is recommended, especially in areas likely to be impacted by fires after earthquakes, due to the anticipated damage to the main water distribution system as a result of ground failure due to fault rupture, liquefaction, or landsliding. 5.3 Fire Suppression Responsibilities The Newport Beach Fire Department is responsible for fire suppression within the City of Newport (t—j Beach. The Newport Beach Fire Department constantly monitors the fire hazard in the City, and t— . has ongoing programs for investigation and alleviation of hazardous situations. Fire fighting resources in Newport Beach area include Fire Station Nos. 1 through 8, as shown on Table 5-2 Earth Consultants International Fire Hazards Page 5-28 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • below. The general telephone number for the Newport Beach fire department is 949-644-3104. For emergencies, dial 911. Table 5-2: Fire Stations in the City of Newport Beach Fire Station No. Street Address Location Area Units Available Ladder Trucks Engine Companies Paramedic Ambulances 1 110 Balboa Blvd. East Balboa 0 1 0 2 475 32" St. Lido 1 1 1 3 868 Santa Barbara Dr. Newport Center 1 1 1 4 124 Marine Avenue Balboa Island 0 1 0 5 410 Marigold Avenue Corona del Mar 0 1 1 6 1348 Irvine Avenue Mariners 0 1 0 7 2301 Zenith Avenue Santa Ana Heights 0 1 0 8 6502 Ridge Park Road Newport Coast 0 l 0 Each engine or truck company has a staff of three persons per 24-hour shift. Each paramedic ambulance has a staff of two firefighter -paramedics per 24-hour shift. Statistics from the Newport Beach Fire Department regarding incidents that they responded to during 2002 are summarized in Table 5-3, below. • Table 5-3: 2002 Statistics, City of Newport Beach Fire Department Type of Incident Sub -Type Responses in 2002 Fires Structural 139 Vehicles 81 Brush / vegetation 30 Miscellaneous / Other 188 Total Fires 438 Medical Emergencies 5,717 Fire Alarms 1,164 Other Emergencies (such as Hazardous Materials) 130 Public Assistance 868 Total Number of Incidents 8,317 The table above shows that the eight fire stations in the City of Newport Beach responded to 8,317 incidents in 2002, which resolves to an average of about 1,040 incidents per station. Note that 69 percent of the responses were medical emergency calls. This is typical of most communities. In Newport Beach, these medical emergencies are handled by the closest available engine company and the closest paramedic ambulance from one of the three fire stations with paramedic ambulances (Fire Stations 2, 3 and 5). In 2002, each paramedic ambulance responded to 1,903 medical emergencies on average. These numbers are well within the number of calls recommended by the Insurance Services Office (ISO) when rating a community for fire insurance . Earth Consultants International Fire Hazards Page 5-29 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • rates. Specifically, the ISO recommends that a second company be put in service in a fire station if that station receives more than 2,500 calls per year. The reason for this recommendation is to assure reliability of response to a structure fire. If an engine company provides support to the paramedic ambulance by responding to medical aid calls, and this impacts the station's response to structure fire calls, it may be prudent to add another paramedic ambulance or support squad vehicle and increase staffing at that fire station with the most medical aid traffic. A high volume of calls also creates a high potential for multiple calls occurring at once (multiple queuing), which can result in a company being unavailable to respond to a structure fire. Thus, if this forces a response from other stations farther away, it can result in a larger fire before assistance arrives. Fires in Newport Beach represent only about 5 percent of all calls, with structure fires representing less than 2 percent of all calls. This is due to the use of modern fire and building codes, effective fire prevention inspection work by the Fire Department, and effective public education. Fires, when they do occur in newer occupancies, are kept small by fire sprinkler systems and the efforts of the Fire Department. Therefore, in recent years, there has been a concern that in some areas, when a major structure fire does occur, the Fire Department personnel will have to apply "seldom used skills." This can result in firefighter injuries, and perhaps larger fires than would have occurred in past years when Fire Departments were accustomed to responding to more structure fires due to the absence of sprinkler systems, poor construction, and lack of ongoing Code enforcement. The Newport Beach Fire Department, however, participates in extensive fire -fighting training. For emergency response, it is recommended that a 3 to 4-person engine company should arrive • within 5 minutes response time to 90 percent of all structure fire calls in the City. Response time shall be defined as 1 minute to receive and dispatch the call, 1 minute to prepare to respond in the fire station or field, and 3 minutes driving time at 35 miles per hour (mph) average (for an approximate distance not exceeding 1.75 miles between the responding fire station and the incident location). 11 The 5-minute response time is based on the demands created by a structural fire: It is critical to attempt to arrive and intervene at a fire prior to the fire flashing over the entire room or building of origin, which results in total destruction. Flashover can occur within 3 to 5 minutes after ignition. Response time includes the following components: 1 minute: (Call Processing time): Dispatcher receives, processes and dispatches the call. This is an average time, which can vary based upon call volume, from a minimum of 30 seconds. 1 minute: (Turnout time): Fire company acknowledges call and apparatus begins to move. 3 minutes: (Driving Time): Apparatus drives to scene at an average speed of 35 mph. If the average response time for the Fire Department is more than this, and the distance between the closest, responding station and most incidents exceeds 1.5 miles, more fire stations may be needed. If necessary, traffic signal actuation devices (Opticom) can also be installed on critical traffic lights and installed in all fire apparatus to improve the driving time response. Earth Consultants International Fire Hazards Page 5-30 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Actual response statistics for the Newport Beach Fire Department for 2002 and the first five months of 2003 are provided in Table 5-4 below. These response times are measured from the time the dispatch is made to arrival at the scene by the responding engine company. The averages show that the majority of the fire units in the City reach their destination within the preferred 5-minute response time, and all units respond within 6 minutes of the call being received by dispatch. The longer response times are for Fire Station 8 located in Newport Coast, a large area presently serviced by only one fire station. With increasing development in this area, the City should consider the construction of another fire station, possibly in the easternmost portion of Newport Coast, in anticipation of the increasing demand for emergency assistance due to a larger population base. Table 5-4: Average Response Time, from Dispatch to Arrival, for Each Unit in the Newport Beach Fire Department for 2002 and Part of 2003 Units Average Res onse Time (Minutes) Year 2002 Jan - May 2003 NE61(Engine -Station1) 4.09 3.47 NE62 (Engine -Station 2) 4.18 4.18 NM62 (Medical - Station 2) 4.59 5.02 NT62 (Truck -Station 2) 4.44 4.51 NE63 (Engine - Station 3) 4.41 4.36 NM63 (Medical - Station 3) 5.11 5.14 NT63 (Truck -Station 3) 5.00 5.09 NE64(Engine -Station4) 4.44 4.40 NE65(Engine -Stations) 4.22 4.29 NM65 (Medical -Station 5) 5.17 5.38 NE66 (Engine - Station 6) 4.09 4.29 NE67(Engine -Station7) 4.50 5.15 NE68 (Engine - Stati'on 8) 5.58 5.47 a Totals Avers 4.60 1 4.67 In addition to these components, there is another component called "set up" time. This is the time it takes firefighters to get to the source of a fire and get ready to fight the fire. This may range from 2 minutes at a small house fire to 15 minutes or more at a large or multi -story occupancy, such as a fire at Fashion island, Hoag Memorial Hospital, or a large condominium. The 90 percent figure is stated as a goal to be achieved. Regular management audits by the Fire Chief should be conducted to reveal if the goal is being met. In many communities it is difficult to exceed the 90 percent figure in a cost-effective manner due to the following limiting factors: Access obstructions Traffic calming devices and median strips on major highways Traffic congestion Weather Multiple alarms Delayed response Winding access roads in developments . Earth Consultants International Fire Hazards Page 5-31 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Road grades Gated communities Multiple story buildings or large buildings where it takes time to reach the source of the fire, after arrival at the occupancy. A 3 to 4-person ladder truck company, with an aerial device, a second engine company with 3 to 4 persons, a paramedic ambulance and a fire battalion chief should arrive within a 10-minute response time interval to 80 percent of all structure fire calls within the City. ISO recommends a truck company within 2.5 miles if there are five or more buildings that are three or more stories or 35 feet or more in height, or five buildings with fire flow needs greater than 3,500 gallons per minute. Fire Station 2 provides this level of service for the high rises on the west side of Newport Beach. Fire Station 3 provides this level of service for the high rises in the Fashion Island and John Wayne Airport areas. An additional truck company from Costa Mesa or Santa Ana can respond via automatic aid if within 5 miles of the City limits. Structural fire response requires numerous critical tasks to be performed simultaneously. The number of firefighters required to perform the tasks varies based upon the risk. Obviously, the number of firefighters needed at a maximum high -risk occupancy, such as a shopping mall or large industrial occupancy would be significantly higher than for a fire in a lower -risk occupancy. Given the large number of firefighters that are required to respond to a high -risk, high - consequence fire, Fire Departments increasingly rely on automatic and mutual aid agreements to address the fires suppression needs of their community. If additional resources are needed due to the intensity or size of the fire, a second alarm may be requested. The second alarm results in the • response of at least another two engine companies, and a ladder truck. Beyond this response, additional fire units are requested via the automatic or mutual aid agreements. 5.3.1 Automatic and Mutual Aid Agreements Although the City of Newport Beach Fire Department is tasked with the responsibility of fire prevention and fire suppression in the City, in reality, fire -fighting agencies generally team up and work together during emergencies. These teaming arrangements are handled through automatic and mutual aid agreements. The California Disaster and Civil Defense Master Mutual Aid Agreement (California Government Code Section 8555-8561) states: "Each party that is signatory to the !l�iVV agreement shall prepare operational plans to use within their jurisdiction, and outside their area." These plans included fire and non -fire emergencies related to natural, technological, and war contingencies. The State of California, all State agencies, all political subdivisions, and all fire districts signed this agreement in 1950. Section 8568 of the California Emergency Services Act, (California Government Code, Chapter 7 of Division 1 of Part 2) states that "the State Emergency Plan shall be in effect in each political subdivision of the State, and the governing body of each political subdivision shall take such action as may be necessary to carry out the provisions thereof." The Act provides the basic authorities for conducting emergency operations following the proclamations of emergencies by the Governor or appropriate local authority, such as a City Manager. The provisions of the act are further reflected and expanded on by . appropriate local emergency ordinances. The act further describes the function and operations of government at all levels during extraordinary emergencies, including war Earth Consultants International Fire Hazards Page 5-32 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA •(www.scesa.org/cal_govcode.htm). Therefore, local emergency plans are considered extensions of the California Emergency Plan. Newport Beach has automatic aid agreements with the cities of Costa Mesa, Santa Ana, a Huntington Beach, and Fountain Valley, and with the Orange County Fire Authority. These agreements obligate these fire departments to help each other under pre -defined circumstances. Automatic aid agreements obligate the nearest fire company to respond to a fire regardless of the jurisdiction. Mutual aid agreements obligate fire department resources to respond outside of their district upon request for assistance. Numerous other agencies are available to assist the City if needed. These include local law enforcement agencies that can provide support during evacuations and to discourage people from traveling to the fire zone to watch the fire, as this can hinder fire suppression efforts. Several State and Federal agencies have roles in fire hazard mitigation, response, and recovery, including: the Office of Emergency Services, the Fish and Wildlife Service, National Park Service, US Forest Service, Office of Aviation Services, National Weather Service, and National Association of State Foresters, the Department of Agriculture, the Department of the Interior, and, in extreme cases, the Department of Defense. Private companies and individuals may also assist. 5.3.2 Standardized Emergency Management System (SEMS) The SEMS law refers to the Standardized Emergency Management System described by the Petris Bill (Senate Bill 1841; California Government Code Section 8607, made effective • January 1, 1993) that was introduced by Senator Petris following the 1991 Oakland fires. The intent of the SEMS law is to improve the coordination of State and local emergency response in California. It requires all jurisdictions within the State of California to participate in the establishment of a standardized statewide emergency management system. When a major incident occurs, the first few moments are absolutely critical in terms of reducing loss of life and property. First responders must be sufficiently trained to understand the nature and the gravity of the event to minimize the confusion that inevitably follows catastrophic situations. The first responder must then put into motion relevant mitigation plans to further reduce the potential for loss of lives and property damage, and to communicate with the public. According to the State's Standardized Emergency Management System, local agencies have primary authority regarding rescue and treatment of casualties, and making decisions regarding protective actions for the community. This on -scene authority rests with the local emergency services organization and the incident commander. Depending on the type of incident, several different agencies and disciplines may be called in to assist with emergency response. Agencies and disciplines that can be expected to be part of an emergency response team include medical, health, fire and rescue, police, public works, and coroner. The challenge is to accomplish the work at hand in the most effective manner, maintaining open lines of communication between the different responding agencies to share and disseminate information, and to coordinate efforts. • Earth Consultants International Fire Hazards Page 5-33 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA isEmergency response in every jurisdiction in the State of California is handled in accordance with SEMS, with individual City agencies and personnel taking on their responsibilities as defined by the City's Emergency Plan. This document describes the different levels of emergencies, the local emergency management organization, and the specific responsibilities of each participating agency, government office, and City staff. The framework of the SEMS system is the following: Incident Command System — a standard response system for all hazards that is based on a concept originally developed in the 1970s for response to wildland fires Multi -Agency Coordination System — coordinated effort between various agencies and disciplines, allowing for effective decision -making, sharing of resources, and prioritizing of incidents Master Mutual Aid Agreement and related systems — agreement between cities, counties and the State to provide services, personnel and facilities when local resources are inadequate to handle and emergency Operational Area Concept — coordination of resources and information at the county level, including political subdivisions within the county; and Operational Area Satellite Information System - a satellite -based communications system with a high -frequency radio backup that permits the transfer of information between agencies using the system. • The SEMS law requires the following: jurisdictions must attend training sessions for the emergency management system. All agencies must use the system to be eligible for funding for response costs under disaster assistance programs. All agencies must complete after -action reports within 120 days of each declared disaster. 5.3.3 ISO Rating for the City of Newport Beach The Insurance Services Office provides rating and statistical information for the insurance industry in the United States. To do so, ISO evaluates a community's fire protection needs and services, and assigns each community evaluated a Public Protection Classification (PPC) rating. The rating is developed as a cumulative point system, based on the community's fire -suppression delivery system, including fire dispatch (operators, alarm dispatch circuits, telephone lines available), fire department (equipment available, personnel, training, distribution of companies, etc.), and water supply (adequacy, condition, number and installation of fire hydrants). Insurance rates are based upon this rating. The worst rating is a Class 10. The best is a Class 1. Newport Beach currently has a a Class 2 ISO rating. • 5.4 Earthquake -Induced Fires Although wildland fires can be devastating, earthquake -induced fires have the potential to be the Earth Consultants International Fire Hazards Page 5-34 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . worst -case fire -suppression scenarios for a community because an earthquake typically causes multiple ignitions distributed over a broad geographic area. In addition, if fire fighters are involved with search and rescue operations, they are less available to fight fires, and the water distribution system could be impaired, limiting even further the fire suppression efforts. If earthquake -induced fires occur during Santa Ana wind conditions, the results can be far worse. The major urban conflagrations of yesteryear in major cities were often the result of closely built, congested areas of attached buildings with no fire sprinklers, no adequate fire separations, no Fire Code enforcement, and narrow streets. In the past, fire apparatus and water supplies were also inadequate in many large cities, and many fire departments were comprised of volunteers. Many of these conditions no longer apply to the cities of today. Nevertheless, major earthquakes can result in fires and the loss of water supply, as it occurred in San Francisco in 1906, and more recently in Kobe, Japan in 1995. A large portion of the structural damage caused by the great San Francisco earthquake of 1906 was the result of fires rather than ground shaking. The moderately sized, M 6.7 Northridge earthquake of 1994 caused 15,021 natural gas leaks that resulted in three street fires, 51 structural fires (23 of these caused total ruin) and the destruction by fire of 172 mobile homes. In one incident, the earthquake severed a 22- inch gas transmission line and a motorist ignited the gas while attempting to restart his stalled vehicle. Response to this fire was impeded by the earthquake's rupture of a water main; five nearby homes were destroyed. Elsewhere, one mobile home fire started when a ruptured transmission line was ignited by a downed power line. In many of the destroyed mobile homes, fires erupted when inadequate bracing allowed the houses to slip off their foundations, severing • gas lines and igniting fires. There was a much greater incidence of mobile home fires (49.1 per thousand) than other structure fires (1.1 per thousand). Although the threat that existed in San Francisco in 1906 was far greater than that in Newport Beach today, there are some older sections in Newport Beach where due to ground failure, breaks in the gas mains and the water distribution system could lead to a significant fire -after -earthquake situation. As discussed in the Seismic Hazards section of this report (Chapter 2), there are several major earthquake -generating faults that could affect the Newport Beach area. The three most significant faults to the Newport Beach area include the Newport -Inglewood, San Joaquin Hills, and Whittier faults. A moderate to strong earthquake on any of these faults could trigger multiple fires, disrupt lifelines services (such as the water supply), and trigger other geologic hazards, such as landslides or rock -falls, which could block roads and hinder disaster response. The California Division of Mines and Geology (Toppozada and others, 1988) published' in 1988 a study that identified projected damages in the Los Angeles area as a result of an earthquake on the Newport -Inglewood fault. The earthquake scenario estimated that thousands of gas leaks would result from damage to pipelines, valves and service connections. This study prompted the Southern California Gas Company to start replacing their distribution pipelines with flexible plastic polyethylene pipe, and to develop ways to isolate and shut off sections of supply lines when breaks are severe. Nevertheless, as a result of the 1994 Northridge earthquake, the Southern California Gas Company reported 35 breaks in its natural gas transmission lines and 717 breaks in distribution lines. About 74 percent of its 752 leaks were corrosion related. Furthermore, in the aftermath of the earthquake, 122,886 gas meters were closed by customers or emergency personnel. The majority of the leaks were small and could be repaired at the time of service restoration. • History indicates that fires following an earthquake have the potential to severely tax the local fire Consultants International Fire Hazards ' Page 5-35 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • suppression agencies, and develop into a worst -case scenario. Earthquake -induced fires can place extraordinary demands on fire suppression resources because of multiple ignitions. The principal causes of earthquake -related fires are open flames, electrical malfunctions, gas leaks, and chemical spills. Downed power lines may ignite fires if the lines do not automatically de -energize. Unanchored gas heaters and water heaters are common problems, as these readily tip over during strong ground shaking (State law now requires new and replaced gas -fired water heaters to be attached to a wall or other support). Many factors affect the severity of fires following an earthquake, including ignition sources, types and density of fuel, weather conditions, functionality of the water systems, and the ability of firefighters to suppress the fires. Casualties, debris and poor access can all limit fire -fighting effectiveness. Water availability in Orange County following a major earthquake will most likely be curtailed due to damage to the water distribution system — broken water mains, damage to the aqueduct system, damage to above -ground reservoirs, etc. (see Chapter 2 — Seismic Hazards, and Chapter 4 — Flooding Hazards). 5.4.1 Earthquake -Induced Fire Scenarios for the Newport Beach Area using HAZUS HAZUSTm is a standardized methodology for earthquake loss estimation based on a geographic information system (GIS). The user can run the program to estimate the damage and losses that an earthquake on a specific fault would generate in a specific geographic area, such as a city. Detailed information on this methodology is covered in Chapter 2. One of the HAZUS components is earthquake -induced fire loss estimation. • Loss estimation is a new methodology, and our understanding of fires following earthquakes is limited. An accurate, fire -following -earthquake evaluation possibly requires extensive knowledge of the level of readiness of local fire departments, as well as the types and availability (functionality) of water systems, among other data. Although these parameters are not yet considered in the fire -after -earthquake module, preliminary results obtained from this HAZUS component are encouraging. Current data suggest that about 70% of all earthquake -induced fire ignitions occur immediately after an earthquake since many fires are discovered within a few minutes after an earthquake. The remaining ignitions occur about an hour to a day after the earthquake. A typical cause of the delayed ignitions is the restoration of electric power. When power is restored, short circuits caused by the earthquake become energized and can start fires. Also, items that have overturned or fallen onto stove tops, etc., can ignite. If no one is present at the time electric power is restored, ignitions can develop into fires requiring fire department response. HAZUS loss estimations were made for earthquake scenarios on the Newport -Inglewood, San Joaquin Hills, Whittier and San Andreas faults (refer to Chapter 2 for additional information on each of these earthquake scenarios). Two wind speeds were used for each earthquake scenario. A value of 10 mph was used to model normal wind conditions. A speed of 30 miles per hour (mph) was assigned to evaluate fire spread as a result of Santa Ana winds. HAZUS uses a Monte Carlo simulation model to estimate the number of ignitions and the amount of burnt area that each earthquake scenario is likely to generate. • Note that the HAZUS loss estimation does not consider effects of reduced water pressure Consultants International Fire Hazards Page 5-36 100% HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • due to breaks in the water distribution system. These are expected to be widespread where ground failure occurs, especially in the area near the coastline where liquefaction damage is anticipated. This would further reduce functionality in some areas, such as the Balboa Peninsula and Balboa Island areas. • Table 5-5 shows that earthquakes on the Newport -Inglewood and San Joaquin Hills faults have the potential to cause significant fire -after -earthquake losses in the City of Newport Beach. The HAZUS results show that wind speeds definitely have an impact on the damage extent The San Joaquin Hills fault fire -after -earthquake scenario is modeled as the worst case for the City of Newport Beach if Santa Ana wind conditions are present at the time of the earthquake, with the Newport -Inglewood earthquake scenario a close second. Rupture of the Newport -Inglewood fault, if it breaks along the traces of the fault thought to extend into the City of Newport Beach and surrounding communities, is anticipated to cause many breaks in the gas and water distribution systems. Therefore, retrofitting those pipe sections across and near the mapped trace of these faults with flexible plastic polyethylene pipe and flexible joints should be a priority. Breakage of the San Andreas fault is regionally significant, as it could impact the distribution of water to many cities in the southern California area that purchase water from the Metropolitan Water District Table 5-5: Earthquake -Induced Fire Losses in Newport Beach Based on HAZUS Scenario Earthquakes Earthquake Scenario (refer to Chapter 2 for additional information) No. of ignitions Population Displaced At a Wind Speed of Building Value Burnt At a Wind Speed of (US$ millions) 10 mph 30 mph 10 mph 30 mph 10 mph 30 mph Newport -Inglewood 9 9 353 1,553 24.42 109.08 San Joaquin Hills 12 12 569 1,906 38.36 133.65 Whittier 3 3 70 422 5.66 38.40 San Andreas 1 1 48 291 3.31 19.94 The Newport Beach Fire Department has procedures in place to follow immediately after(� an earthquake. In accordance with their Earthquake Response Plan, immediately after an VJ earth tremor, fire apparatus and other response vehicles are taken out of the stations and parked outside. Then, personnel from each station drive around their district to assess the damage, if any, and provide assistance as needed. . Earth Consultants International Fire Hazards Page 5-37 2003 • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA 5.5 Recommended Programs The City of Newport Beach: Should continue to require property owners to conduct maintenance on their properties to reduce the fire danger in accordance with the property owner's checklist presented above. The single most important mitigation measure for a single-family residence is to maintain a fire -safe landscape, thereby creating a defensible space around the structure(s). Should support the new State -level shift in its vegetation management program. Emphases are on smaller projects closer to new developments, and alternatives to fire treatment, such as weed abatement using mechanical treatments. Should continue to develop education and mitigation strategies that focus on the enhanced or higher hazard present in the months of August, September and October, when dry vegetation and Santa Ana winds coexist. Should regularly reevaluate specific fire hazard areas and adopt reasonable safety standards, covering such elements as adequacy of nearby water supplies, routes or throughways for fire equipment, clarity of addresses and street signs, and maintenance. Encourage owners of non-sprinklered properties, especially high- and mid -rise structures, to retrofit their buildings and include internal fire sprinklers. The City may consider some form of financial assistance (such as low -interest or no -interest loans) to encourage property owners to do this as soon as possible. Staff, as well as elected officials, should conduct earthquake -induced fire -scenario exercises based on this study's HAZUS loss estimates. Staff should continue to conduct annual training sessions using the adopted emergency management system (SEMS). Should review the adequacy of its water storage capacity and distribution network in the event of an earthquake. Redundant systems should be considered and implemented in those areas of the City where liquefaction and other modes of ground failure could result in breaks to both the water and gas mains, with the potential for significant conflagrations. This includes considering alternate sources of water, such as the ocean, bay, open reservoirs, and swimming pools, and providing fire engines with engine -driven pumps that can be used to obtain water from these alternate sources. Should encourage the local gas and water purveyors to review and retrofit their main distribution pipes, with priority given first to those lines that cross or are located near the mapped trace or projections of the Newport -Inglewood fault (see Chapter 2). Earth Consultants 2003 Fire Hazards Page 5-38 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • References, Helpful Websites and Acknowledgements ASTM E-108, "Standard Test Methods for Fire Tests of Roof Coverings": American Society for Testing Materials. California Board of Forestry, 1996, California Fire Plan: A Framework for Minimizing Costs and Losses from Wildland Fires: a report dated March 1996. California Department of Forestry, 1993, Rater Instruction Guide: Very High Fire Hazard Severity Zone. Cannon, S.H., 2001, Debris -Flow Generation from Recently Burned Watersheds: Environmental & Engineering Geosciences, Vol. VII, No. 4, November 2001, pp. 321-341. Coleman, Ronny J., 1994, Policy Context on Urban-Widland Fire Problem: California State and Consumer Services Agency, A Special Report for the Governor Pete Wilson, dated January 19, 1994, 13p. Fisher, Fred L., 1995, Building Fire Safety in the Wildland Urban Intermix: The Role of Building Codes and Fire Test Standards: Report prepared for the California/China Bilateral Conference on Fire Safety Engineering held August 14-15, 1995 in Sacramento, California, 13 p. Greenlee, J., and Sapsis, D., 1996, Prefire Effectiveness in Fire Management: A Summary of State - of -Knowledge: dated August 1996. Can be obtained from www.ucfpl.ucop.edu/UWI%2ODocuments/103.PDF. Helm, R., Neal, B., and Taylor, L., 1973, A Fire Hazard Severity Classification System for California's Wildlands: A report by the Department of Housing and Urban Development and the California Department of Conservation, Division of Forestry to the Governor's Office of Planning and Research, dated April 1, 1973. Insurance Services Office, Inc. (ISO), 2001, Guide for Determination of Needed Fire Flow: Edition 10-2001, 26p. Insurance Services Office, Inc. (ISO), 1997, The Wildland/Urban Fire Hazard: ISO, New York, December 1997. National Fire Protection Association (NFPA), 2001, Standard for the Organization and Deployment of Fire Suppression Operations, Emergency Medical Operations and Special Operations to the Public by Career Fire Departments: NFPA Standard 1710, 2001 Edition. Phillips, Clinton B., 1983, Instructions for Zoning Fire Hazard Severity in State Responsibility Areas in California: California Department of Forestry, dated December 1983. Site that pertains to California laws about fires and firefighters: http://osfm.fire.ca.gov/FFLaws.html • California Department of Forestry and Fire Protection's Web Site: http://www.fire.ca.gov/ Earth Consultants International Fire Hazards Page 5-39 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • California Fire Plan: http://www.fire.ca.gov/FireEmergencyResponse/FirePlan/FirePlan.asp National Fire Plan: http://www.fireplan.gov Orange County Fire Authority's Web Site: http://www.ocfa.oLW National Fire Protection Association Web Site: htto://nfpa.oie/ Site dedicated to providing information to homeowners about becoming firewise in the urban/wildland interface: http://firewise.ore/ Federal Emergency Management Agency Web Site; includes general information on how to prepare for wildfire season, current fire events, etc.: htto://www.fema.gov/ U.S. Fire Administration Web Site: http://www.usfa.fema.gov/ Insurance Services Office Web Site: http://www.iso.com This documents was prepared with the assistance from many individuals from the Newport Beach Fire Department. ECI would like to acknowledge the help received from Mr. Daryl Mackey, Chief Dennis Lockard, Mr. Riley, Mr. Ron Soto, Ms. Nadine Morris, and many others in the Fire Department. Mr. Scott Watson, CIS Specialist with the City of Newport • Beach, was also very helpful in providing us with the data necessary to prepare the Plates that accompany this report. • Earth Consultants International Fire Hazards Page 5-40 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • CHAPTER 6: HAZARDOUS MATERIALS MANAGEMENT 6.1 Introduction A high standard of living has driven society's increased dependence on chemicals. Hydrocarbon fuels that power our vehicles, chlorine used to treat our drinking water and pools, and pesticides used in the agricultural sector are a few examples of chemicals used on a daily basis and in large quantities. This demand requires the manufacturing, transportation and storage of chemicals. As we will discuss throughout this chapter, these activities provide opportunities for the release of chemicals into the environment, sometimes with negative consequences because exposure to many of these chemicals is often hazardous to human health and to the environment. Recognizing these potential health hazards, Federal, State, and local regulations have been implemented since the late 1960's to dictate the safe use, storage, transportation, and handling of hazardous materials and wastes. These regulations help to minimize the public's risk of exposure to hazardous materials. The United States Environmental Protection Agency (EPA) defines a hazardous waste as a substance that 1) may cause or significantly contribute to an increase in mortality or an increase in serious, irreversible, or incapacitating reversible illness; and 2) that poses a substantial present or potential future hazard to human health or the environment when it is improperly treated, stored, transported, disposed of or otherwise managed. Hazardous waste is also ignitable, corrosive, explosive, or reactive (Federal Code of Regulations — FCR - Title 40: Protection of the Environment, Part 261). A material may also be classified as a hazardous material if it contains defined amounts of toxic chemicals. The EPA has developed a list of • specific hazardous wastes that are in the forms of solids, semi -solids, liquids, and gases. Producers of such wastes include private businesses, and Federal, State, and local government agencies. The EPA regulates the production and distribution of commercial and industrial chemicals to protect human health and the environment. The EPA also prepares and distributes information to further the public's knowledge about these chemicals and their effects, and provides guidance to manufacturers in pollution prevention measures, such as more efficient manufacturing processes and recycling used materials. The State of California defines hazardous materials as substances that are toxic, ignitable or flammable, reactive, and/or corrosive. The State also defines an extremely hazardous material as a substance that shows high acute or chronic toxicity, is carcinogenic (causes cancer), has bioaccumulative properties (accumulates in the body's tissues), is persistent in the environment, or is water reactive (California Code of Regulations, Title 22; California Health and Safety Code, Division 20, Chapter 6.5). This report will deal with hazards associated with the existence of hazardous wastes and materials in the City of Newport Beach and its Sphere of Influence (herein referred to as the Newport Beach area), with emphasis on the impact these substances can have on the air we breathe or the drinking water supply. There are hundreds of Federal, State and local programs that regulate the use, storage, and transportation of hazardous materials in the City. Some of these programs are discussed in this report. However, the environmental regulatory scene is in a constant state of flux as new findings are published, and new or modified methods for studying and cleaning contaminants are developed. Therefore, for recent updates, the reader • is encouraged to contact the City of Newport Beach Fire Department, the Orange County Health Care Agency's Environmental Division, and/or the U.S. Environmental Protection Earth Consultants International Hazardous Materials Management Page 6-1 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Agency. All of these agencies have dedicated web pages where extensive information about hazardous wastes is provided. This report also addresses the potential for hazardous materials to be released during a natural disaster, such as an earthquake, since these events have the potential to cause multiple releases of hazardous materials at the same time, taxing the local emergency response agencies. • 6.2 Air Quality Each one of us breathes about 3,400 gallons of air every day. Unfortunately, our air is contaminated on a daily basis by human activities such as driving cars, burning fossil fuels, and manufacturing chemicals. Natural events, such as wildfires, windstorms, and volcanic eruptions also degrade air quality. Nevertheless, during the last three decades, the United States has made impressive strides in improving and protecting air quality despite substantial economic expansion and population growth. However, as any resident of the greater Los Angeles metropolitan area can attest, additional improvements in air quality can and should be made. 6.2.1 National Ambient Air Quality Standards The Clean Air Act requires the EPA to set National Ambient Air Quality Standards for pollutants considered harmful to public health and the environment. The EPA uses two types of national air quality standards: Primary standards set limits to protect public health, including the health of "sensitive" populations such as asthmatics, children, and the elderly, and secondary standards set limits to protect public welfare, including protection against decreased visibility, damage to animals, crops, vegetation, and buildings. National Ambient Air Quality Standards have been set for six principal pollutants called "criteria" pollutants. These pollutants include: Carbon monoxide (CO) Particulate matter (PM10) Lead (Pb) Nitrogen dioxide (NOZ) Ground -level' ozone (Oi) Sulfur dioxide (SO2) For each of these pollutants, the EPA tracks two kinds of air pollution trends: air concentrations based on actual measurements of pollutant concentrations in the ambient (outside) air at selected monitoring sites throughout the country, and emissions based on engineering estimates of the total tons of pollutants released into the air each year. The standards or allowable concentrations for these six pollutants are known as National Ambient Air Quality Standards (NAAQS). These are listed in Table 6-1. California has established State standards for some of these pollutants that are more restrictive than the National standards. These are also shown on Table 6-1. The health effects of two of these pollutants, ozone and particulate matter, are discussed further below. Earth Consultants International Hazardous Materials Management Page 6-2 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Table 6-1: National Ambient Air Quality Standards (where California standards are different than National standards, California standards are also provided) • Pollutant Allowable Concentration Type In parts per million* In mg/m' or pg1m' Carbon Monoxide 8-hour average (U.S.) 8-hour average (CA) t9.5 >9.0 Primary 1-hour average (U.S.) 1-hour average (CA) >35 >20 Primary Nitrogen Dioxide AAM (U.S.) 1-hour average (CA) >0.0534 >0.25 Primary and Secondary Ozone 1-hour average (U.S.) 1-hour average (CA) >0.12 >0.09 Primary and Secondary 8-hour average >0.08 Primary and Secondary Lead Quarterly average (U.S.) Monthly average (CA) >1.5 pg/m' t1.5 m' Primary and Secondary Particulate (PM 10) AAM (U.S.) AGM (CA) >50 pg/m' >30 Pg1m, Primary and Secondary 24-hour average (U.S.) 24-houraverage (CA) >150 pg/m' >50 pgIM3 Primary and Secondary Particulate (PM 2.5) AAM (U.S.) >15 m' Primary and Secondary 24-hour average (U.S.) >65 m' Primary and Secondar Sulfur Dioxide AAM (U.S.) >0.03 Primary 24-hour average (U.S.) 24-hour average (CA) >0.14 >0.045 Primary 3-hour average (U.S.) 1-hour average (CA) >0.50 >0.25 Secondary * Parts per million, ppm, of air, by volume AAM = Annual Arithmetic Mean; AGM = Annual Geometric Mean PM 10 refers to particles with diameters of 10 micrometers or less. PM 2.5 refers to particles with diameters of 2.5 micrometers or less. The ozone 8-hour standard and the PM 2.5 standards are included for information only, since a 1999 Federal court ruling blocked implementation of these standards, and the issue has not yet been resolved. mg(m'= milligrams per cubic meter; pg(m'= micrograms per cubic meter U.S. = Federal (or National) Standard; CA = California Standard • Earth Consultants International Hazardous Materials Management Page 6-3 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Ozone is an odorless, colorless gas that occurs naturally in the Earth's upper atmosphere — 10 to 30 miles above the Earth's surface — where it forms a protective layer that shields us from the sun's harmful ultraviolet rays. The releases of man-made chemicals, such as chlorofluorocarbons (CFCs), and natural emissions from volcanic eruptions destroy this beneficial ozone, resulting in seasonal thinning of the ozone layer over Antarctica. In the Earth's lower atmosphere, near ground level, ozone is formed when pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants, and other sources react chemically in the presence of sunlight. Ozone at ground level is a harmful pollutant. Ozone pollution is a concern during the summer months, when the weather conditions needed to form it — 'lots of sun and hot temperatures— normally occur. Roughly one out of every three people in the United States is at a higher risk of experiencing ozone -related health effects. Sensitive people include children and adults who are active outdoors, people with respiratory disease, such as asthma, and people with unusual sensitivity to ozone. People of all ages who are active outdoors are at increased risk because, during physical activity, ozone penetrates deeper into the parts of the lungs that are more vulnerable to injury. Ozone can irritate the respiratory system, causing coughing, throat irritation, and/or an uncomfortable sensation in the chest, and aggravating asthma. Ozone can also reduce lung function, making it more difficult to breathe deeply and vigorously, and can increase susceptibility to respiratory infections. • The term "particulate matter" (PM) includes both solid particles and liquid droplets found in air. Many man-made and natural sources emit PM directly or emit other pollutants that react in the atmosphere to form PM. These solid and liquid particles come in a wide range of sizes. Particles less than 10 micrometers in diameter tend to pose the greatest health concern because they can be inhaled into and accumulate in the respiratory system. Particles less than 2.5 micrometers in diameter are referred to as "fine" particles. Sources of fine particles include all types of combustion (motor vehicles, power plants, wood burning, etc.) and some industrial processes. Particles with diameters between 2.5 and 10 micrometers are referred to as "coarse." Sources of coarse particles include crushing or grinding operations, and dust from paved and unpaved roads, and agricultural or vacant fields (think Santa Ana wind conditions). Both fine and coarse particles can accumulate in the respiratory system and are associated with numerous health effects. Coarse particles can aggravate respiratory conditions such as asthma. Exposure to fine particles is associated with several serious health effects, including premature death. Adverse health effects have been associated with exposures to PM over both short periods (such as a day) and longer periods (a year or more). Peak air quality statistics for the six principal pollutants measured in the year 2001 in (t the North Coastal Orange County area, which includes Newport Beach, are listed in V Table 6-2. The data show that none of the peak values in the North Coastal Orange County area exceeded the National or State ambient air quality standards, with one • exception: The maximum allowable concentration of ozone defined by the State for a 1-hour period (of more than 0.09 parts per million) was exceeded only one day in Earth Consultants International Hazardous Materials Management Page 6-4 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . 2001 (also see Table 6-4). As of the writing of this report, the 2002 air quality data were not yet available. The reader is encouraged to go to http://www.aqmd,.gav to look for more recent air quality information, which is posted by the South Coast Air Quality Management District as it becomes available. Table 6-2: Year 2001 Peak Air Quality Statistics for Criteria Pollutants in the North Coastal Orange County Area (compared, unless otherwise noted, to the California Standards, which are more restrictive than the National standards) • Pollutant Sate Air Quality Standard Maximum Concentration in North Coastal Orange County Area Carbon Monoxide 8-hour avera a >9 pprn 4.57 ppm Nitrogen Dioxide 1-hour average >0.25 ppm 0.08 Ppm Ozone 1-houraverage >0.09 ppm 0.098 ppm 8-hour average (U.S.) >0.08 ppm 0.073 ppm Lead Monthly maximum Z1.5 p NM Particulate (PM 10) Annual Geometric Mean >30 VgtM3 NM 24-hour avera a (U.S.) 150 pgtm3 NM Sulfur Dioxide 1-hour average >0.25 m 0.01 m 24-hour average >0.045 m 0.007 ppm ppm = parts per million; pg/m3= micrograms per cubic meter; NM = Pollutant Not Monitored Source: httR://www.el2a.gov/airtrends 6.2.2 Air Quality Index There are two indicators that are typically used to assess the air quality of a given area. These indicators are the Air Quality Index and the quantity of pollutant emissions. In 1976, EPA developed the Pollutant Standards Index (PSI), which was a consistent and easy to understand way of stating air pollutant concentrations and associated health implications. In June 2000, the EPA updated the index and renamed it Air Quality Index (AQI). EPA's AQI provides accurate, timely, and easily understandable information about daily levels of air pollution. The Index provides a uniform system for measuring pollution levels for five major air pollutants regulated under the Clean Air Act. The AQI is reported as a numerical value between 0 and 500, which corresponds to a health descriptor like "good," or "unhealthy" (see Table 5-3). AQI values are reported • Earth Consultants International Hazardous Materials Management Page 6-5 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • daily in the local news media (TV, radio, internet (http://www.epa.gov/airnow), and newspapers) serving metropolitan areas with populations exceeding 350,000. The AQI converts daily measured pollutant concentration in a community's air to a numerical value and color code. The most important number on the scale is 100. An AQI level in excess of 100 means that a pollutant is in the "unhealthy for sensitive groups" range for that day. An AQI level at or below 100 means that a pollutant reading is in the satisfactory range with respect to the National Ambient Air Quality Standard (NAAQS). • Table 6-3: Air Quality Index (a measure of community -wide air quality) Index Levels Values of Health Cautionary Statements Concern 0-50 Good None Unusually sensitive people should consider limiting .51-100* Moderate prolonged outdoor exertion. Unhealthy for Active children and adults, and people with respiratory 101-150 disease, such as asthma, should limit prolonged outdoor Sensitive Groups exertion. Active children and adults, and people with respiratory 151-200 Unhealthy disease, such as asthma, should avoid prolonged outdoor exertion; everyone else, especially children, should limit prolonged outdoor exertion. Source: www.e ap .gov/airnow/agibroch/agi.html#8 The EPA determines, on a daily basis, the index value for each of the measured pollutants, and reports the highest figure as the AQI value for the day. The pollutant with the highest daily value is identified as the Main Pollutant. The pollutants indexed by the AQI are the criteria pollutants discussed earlier. The Clean Air Act directs the EPA to regulate criteria pollutants because of their impact on human health and the environment. The standards or allowable concentrations for these six pollutants are known as National Ambient Air Quality Standards (NAAQS). The South Coast Air Quality Management District (SCAQMD) monitors and provides NAAQS air quality data for the Los Angeles, Orange, Riverside, and San Bernardino counties. The most recent year for which these data are available is 2001. The last column in Table 6-4 provides the number of days that Criteria Air Pollutant concentrations for the area around Newport Beach were in excess of Federal or State standards for the year 2001. Earth Consultants International Hazardous Materials Management 2003 Page 6-6 • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Table 64: Air Quality in the Newport Beach Area in 2001 Pollutant Measurement Location # Days in excess Ozone North Coastal Orange County1* Carbon Monoxide North Coastal Orange County 0** Nitrogen Dioxide North Coastal Orange Count 0*** PM10 North Coastal Orange County NM PM2.5 North Coastal Orange Count NM * 1-hour average California standard 0-hour and 8-hour average Federal standards were not exceeded) ** 8-hour average California standard *** 1-hour average California standard NM = Pollutant not measured Source: www.agmd.gov Significant improvements in the air quality of the larger Los Angeles basin region are attributed to emission reduction and reduced reactivity of emitted organic compounds in the region (SCAQMD, 2001). As everybody who owns a vehicle in California knows, vehicular emissions are monitored through the State's Smog Check Program. Emissions from stationary sources are also monitored. The South Coast Air Quality Management District (SCAQMD) is the local agency responsible for monitoring and enforcing air quality control with emphasis on emissions from stationary sources, such • as restaurants, hotels, dry cleaners, tire shops, welding shops, car repair shops, hospitals, and industrial and manufacturing facilities. Those facilities that release emissions into the air are required to obtain a permit to do so from the EPA. The more recent data available (Hazus99 SR-2) indicate that there are approximately 95 facilities permitted to release emissions into the air in the Newport Beach Area. The regional distribution of these permitted facilities is shown on Plate 6-1. To reduce air emissions, SCAQMD staff conducts periodic inspections of permitted facilities to ensure continued compliance with Federal and State requirements, and provide training to help business owners understand these requirements and keep up with new rules. If necessary, SCAQMD takes enforcement action to bring businesses into compliance. The SCAQMD does not provide a listing of all permitted facilities but it does provide information on facilities that were found to be non -compliant or for which there are violation reports. None of the facilities in the Newport Beach area have been cited in the last 90 days (as of December 1, 2002). For updated information, refer to htti?,//eal.aqmd.goy/­nov/novintro.htm. 6.3 Drinking Water Quality Most people in the United States take for granted that the water that comes out of their kitchen taps is safe to drink. In most areas, this is true, thanks to the efforts of hundreds of behind -the - scene individuals that continually monitor the water supplies for contaminants, in accordance with the drinking water standards set by the EPA. Primary authority for EPA water programs Earth Consultants International Hazardous Materials Management Page 6-7 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Plate 6-1: Hazardous Materials Site Map of Newport Beach • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • was established by the 1986 amendments to the Safe Drinking Water Act (SDWA) and the 1987 amendments to the Clean Water Act (CWA). The National Primary Drinking Water Standard protects drinking water quality by limiting the levels of specific contaminants that are known to occur or have the potential to occur in water, and that can adversely affect public health. All public water systems that provide service to 25 or more individuals are required to satisfy these legally enforceable standards. Water purveyors must monitor for these contaminants on fixed schedules and report to the EPA when a Maximum Contaminant Level (MCL) has been exceeded. MCL is the maximum permissible level of a contaminant in water that is delivered to any user of a public water system. Drinking water supplies are tested for a variety of contaminants, including organic and inorganic chemicals (minerals), substances that are known to cause cancer (carcinogens), radionuclides (such as uranium and radon), and microbial contaminants. The contaminants for which the EPA has established MCLs are listed at htto://www.epa.gov/safewater/mcl.litml. Changes to the MCL list are typically made every three years, as the EPA adds new contaminants or, because, based on new research or new case studies, there are reason to issue revised MCLs for some contaminants. One of the contaminants checked for on a regular basis is the coliform count. Coliform is a group of bacteria primarily found in human and animal intestines and wastes. These bacteria are widely used as indicator organisms to show the presence of such wastes in water and the possible presence of pathogenic (disease -producing) bacteria. Pathogens in these wastes can cause diarrhea, cramps, nausea, headaches, or other symptoms. These pathogens may pose a . special health risk for infants, young children, and people with severely compromised immune systems. One of the fecal coliform bacteria that water samples are routinely tested for is Escherichia coli (E. coli). To fail the monthly Total Coliform Report (TCR), the following must occur: For systems testing more than 40 samples, more than five percent of the samples test positive for Total Coliform, or For those systems testing less than 40 samples, more than one sample tests positive for Total Coliform. Two water agencies provide drinking water to the city of Newport Beach. The two agencies are: • Orange County Water District (OCWD), and • Metropolitan Water District of Orange County (MWDOC) The OCWD is the agency that manages the Orange County Groundwater Basin ("Basin") that serves much of central and north Orange County, including the Newport Beach area. Ground water from four wells beneath the City of Fountain Valley is blended with MWDOC water at Newport Beach's Utilities Yard and distributed to Newport Beach residents. Neither the OCWD, nor the MWDOC, is listed in the EPA Safe Drinking Water Violation Report for Orange County, found at www.epa.gov/enviro/litr-nl/sdwis/sdwis ov.htm1. This means that the water provided by these agencies meets standards for coliform levels and does not exceed the • maximum levels for the contaminants routinely tested Earth Consultants International Hazardous Materials Management Page 6-9 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The Basin receives treated reclaimed water from the Orange County Sanitation District (OCSD). The reclaimed water goes through reverse osmosis and enters or will enter the groundwater basin in one of two ways: (1) direct injection into the seawater intrusion barrier by Water Factory #21; and (2) passive settling into settling ponds at the base of the Santa Ana River near Anaheim and Anaheim Hills (the latter is the so-called Groundwater Replenishment System or GWRS). The Basin's use of reclaimed water to recharge the Basin can and has caused limited contamination of the Basin by at least two "chemicals of concern" for which "action levels" ("ALs") have been set by the California Health Services Department's Division of Drinking Water & Environmental Management. ALs are different from MCLs in that ALs simply require public agencies to notify appropriate agencies that an AL has been reached — water providers are NOT required to remove water from service that has attained an Action Level. The chemicals found in the Basin are NDMA and 1,4-dioxane. In recent years, OCWD has detected both 1,4-dioxane and NDMA at levels at or near ALs at Newport Beach's four well sites. OCWD continues to monitor these and other chemicals of concern on an ongoing basis. According to the EPA, (www.epa.gov/enviro/hti-nl/pcs/pcs querry java.hlml), no facilities in the Newport Beach area have EPA permits to discharge to local water sources. One of the products most often used as a disinfectant by swimming pool, drinking water and wastewater facilities is chlorine, making chlorine one of the most prevalent extremely • hazardous substances. Chlorine is typically found in the form of a colorless to amber -colored liquid, or as a greenish -yellow gas with a characteristic odor. The liquid solutions are generally very unstable, reacting with acids to release chlorine gas (such as bleach mixed with vinegar or toilet bowl cleaner containing hydrochloric acid). Mixing bleach with other products is the largest single source of inhalation exposure reported to poison control centers (http://www emedicine.com/EMERG/topic851.htm). Chlorine gas is heavier than air and therefore stays close to the ground, where it can impact individuals. Exposure to chlorine gas generally impacts the respiratory system, with cough, shortness of breath, chest pain, and burning sensation in the throat reported as the most common symptoms. Respiratory distress can occur at even low concentrations of less than 20 parts per million (ppm). At high concentrations (> 800 parts per million — ppm) chlorine gas is lethal. Chlorine gas is stored at the Big Canyon Reservoir ("BCR"). The City intends to phase out the use of chlorine gas at BCR by 2004 as a result of the covering of BCR. The City will use liquid chlorine to disinfect the water after the cover is installed. Similarly, when the currently empty San Joaquin Reservoir is used as a reclaimed water storage facility (anticipated to be late 2004), the Irvine Ranch Water District will use liquid chlorine as a disinfectant. Chlorine pellets and chlorine solutions can be found at supermarkets, hardware stores and other locations that sell pool supplies. Bleach solutions can be found in almost every household and in commercial and industrial facilities, including hotels, hospitals, medical and veterinary facilities, etc. Proper storage and usage practices are required at all of these locations to reduce or eliminate the potential for a toxic release of chlorine. At larger facilities, • such as the reservoirs mentioned above, proper operations and maintenance are critical to prevent equipment and process failures that could lead to the unauthorized release of chlorine Earth Consultants International Hazardous Materials Management Page 6-10 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • at concentrations that could impact the surrounding areas. These facilities need to maintain a comprehensive program of personnel training, security enforcement and equipment monitoring to reduce the risk of an accidental or intentional (terrorist) release. 6.4 Regulations Governing Hazardous Materials and Environmental Profile of the City of Newport Beach Various Federal and State programs regulate the use, storage, and transportation of hazardous materials. These will be discussed in this report as they pertain to the City of Newport Beach and its management of hazardous materials. The goal of the discussions presented herein is to provide information that can be used to reduce or mitigate the danger that hazardous substances may pose to Newport Beach residents and visitors. Although several of these programs are summarized below, this is not meant to be an all- inclusive list. Hazardous materials management is legislated extensively, and the laws governing hazardous waste are complex and diverse. Several of the agencies involved in this process are identified below. Additional information can be obtained from their web pages. 6.4.1 National Pollutant Discharge Elimination System (NPDES) Stormwater and Dry -Weather Runoff. "Out of sight, out of mind" has traditionally been a common approach to dealing with trash, sediment, fertilizer -laden irrigation water, used motor oil, unused paint and thinner, and other hazardous substances that people dump into the sewer or storm drains. What we often forget is that these • substances eventually make their way into the rivers and oceans, where they can sicken surfers and swimmers, and endanger wildlife. The Clean Water Act of 1972 originally established the National Pollutant Discharge Elimination System (NPDES) to control wastewater discharges from various industries and wastewater treatment plants, known as "point sources." Point sources are defined by the EPA as discrete conveyances such as pipes or direct discharges from businesses or public agencies. Then, in 1987, the Water Quality Act amended the NPDES permit system to include "nonpoint source" pollution (NPS pollution). NPS pollution refers to the introduction of bacteria, sediment, oil and grease, heavy metals, pesticides, fertilizers and other chemicals into our rivers, bays and oceans from less defined sources. These pollutants are washed away from roadways, parking lots, yards, farms, and other areas by rain and dry -weather urban runoff, entering the storm drains, and ultimately the area's streams, bays and ocean. NPS pollution is now thought to account for most water quality problems in the United States. Therefore, strict enforcement of this program at the local level, with everybody doing his or her part to reduce NPS pollution, can make a significant difference. The National Pollutant Discharge Elimination System (NPDES) permit program controls water pollution by regulating point and nonpoint sources that discharge pollutants into waters of the United States. Though individual households do not need NPDES permits, cities like Newport Beach hold NPDES permits to operate their municipal separate storm sewer systems (MS4s). Newport Beach's MS4 Permit (adopted January 2002) directs it to keep pollutants out of its MS4 to the maximum extent practicable and to . ensure that dry -weather flows entering recreational waters from the MS4 do not cause Earth Consultants International Hazardous Materials Management Page 6-11 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA or contribute to exceedances of water quality standards. The Permit requires the City to do the following: • Control contaminants into storm drain systems; • Educate the public about stormwater impacts; • Detect and eliminate illicit discharges; • Control runoff from construction sites; • Implement "best management practices" or "BMPs" and site -specific runoff controls for new development and redevelopment; and • Prevent pollution from municipal operations, including fixed facilities (like City Hall and fire stations) and field activities (like trash collection). Specific programs that local governments typically implement in support of the NPDES program include: Regular maintenance of public rights of way, including street sweeping, litter collection, and storm drain facility maintenance; Implementation of spill response procedures; Periodic screening of water samples collected from the storm sewer system and local streams, to test for specific contaminants; Adoption and enforcement of an ordinance prohibiting the discharge of pollutants into the storm drain system; Plan review procedures to ensure that unauthorized connections to the storm • sewer system are not made; and Public education efforts to inform residents about stormwater quality. These efforts typically include utility bill inserts describing the NPDES program, storm drain stenciling, booths at fairs and other public events, and school programs. The City of Newport Beach has developed the website at http://www.CleanWaterNewport.com/ to describe the local NPDES program and measures that can be taken by businesses and residents alike to reduce the potential for contamination of the local waters. The City of Newport Beach is a member of the County of Orange's Stormwater Program (www.ocwatersheds.com). This program coordinates all cities and the county government in Orange County to regulate and control storm water and urban runoff into all Orange County waterways, and ultimately, into the Pacific Ocean. The Orange County Stormwater Program administers the current NPDES MS4 Permit and the 2003 Drainage Area Management Plan (DAMP) for the County of Orange and the thirty-four incorporated cities within the region. The Orange County NPDES permit serves a population of approximately 2.8 million, occupying an area of approximately 786 square miles. In the Newport Beach Area, NPDES permits are issued by the California Regional Water Quality Control Board, Santa Ana Region. In support of the City's obligation to comply with its MS4 Permit and to keep waterways clean by reducing or eliminating contaminants from stormwater and dry - weather runoff, the City has an aggressive Water Quality Ordinance (Newport Beach Ordinance 97-26). The City has a stormwater education program, an aggressive inspection team that issues citations for water quality violations, and requires the use of Earth Consultants International Hazardous Materials Management Page 6-12 2003 • • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA "best management practices" in many residential, commercial, and development - related activities to reduce runoff. Wastewater. Newport Beach also operates under a Waste Discharge Requirement (WDR) that directs it to effectively manage its wastewater collection system so that it eliminates sanitary sewer overflows (SSOs). SSOs threaten public health and resources by discharging pollutants — including untreated sewage, cleaning chemicals, endocrine disruptors and related medicines, food particles, and laundry and bath waters. 6.4.2 Comprehensive Environmental Response, Compensation and Liability Act The Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA), is a regulatory or statute law developed to protect the water, air, and land resources from the risks created by past chemical disposal practices. This act is also referred to as the Superfund Act, and the sites listed under it are referred to as Superfund sites. According to the most recent EPA data available, there are two CERCLIS sites in the Newport Beach area (see Table 6-5), and both of these are not on the National Priorities List (NPL). The preliminary assessment of the Cagney Trust site was begun in March of 1999, and the study was completed on August 30, 1999. As a result of this study, the Cagney Trust site is considered a No Further Remedial Action Planned (NFRAP) site, and will most likely not be included in next year's Superfund list. The Ford Aerospace/Loral site is, according to the U.S. EPA database, being investigated (Preliminary Assessment Ongoing status). According to City of Newport Beach officials, however, the Regional Water Quality Control Board and the Orange County Health Care Agency both reportedly reviewed and approved the remediation activities conducted at this site prior to its development as part of the One Ford Road residential project. Table 6-5: CERCLIS Sites in the Newport Beach Area Facility Name Facili Address EPA ID Status Cagney Trust SW corner of 32" St. & CA0000187997 Not on NPL New.port Blvd NFRAP Ford Aerospace Facility 3501 jamboree Blvd. A 500 CAD983623257 I Not on NPL, (Loral Aeros ace) PA Ongoing Sources: www.epa.gov/superfund/Sites/arcsites/*index/htm httpJ/www.epa.gov/superfun dtsi tes/cursitesfiin dex.htm http://oaspub.eRa.gov/enviro/multisys web.reoort 6.4.3 Emergency Planning and Community Right -To -Know (EPCRA) The primary purpose of the Federal Emergency Planning and Community Right -To - Know Act (EPCRA) is to inform communities and citizens of chemical hazards in their areas. Sections 311 and 312 of EPCRA require businesses to report to State and local agencies the locations and quantities of chemicals stored on -site. These reports help communities prepare to respond to chemical spills and similar emergencies. This reduces the risk to the community as a whole. • Earth Consultants International Hazardous Materials Management Page 6-13 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA EPCRA mandates that Toxic Release Inventory (TRI) reports be made public. The Toxics Release Inventory (TRI) is an EPA database that contains information on toxic chemical releases and other waste management activities reported annually by certain industry groups as well as federal facilities. This inventory was established in 1986 under the EPCRA and expanded by the Pollution Prevention Act of 1990. Sites on the TRI database are known to release toxic chemicals into the air. The EPA closely monitors the emissions from these facilities to ensure that their annual limits are not exceeded. TRI reports provide accurate information about potentially hazardous chemicals and their uses to the public in an attempt to give the community more power to hold companies accountable and to make informed decisions about how such chemicals should be managed. Section 313 of EPCRA requires manufacturers to report the release to the environment of any of more than 600 designated toxic chemicals. These reports are submitted to the EPA and State agencies. The EPA compiles these data into an on-line, publicly available national digital TRI. These data are readily available on the EPA website at wwwena.gov. Facilities are required to report releases of toxic chemicals to the air, soil, and water. They are also required to report off -site transfers of waste for treatment or disposal at separate facilities. Pollution prevention measures and activities, and chemical recycling must also be reported. All reports must be submitted on or before July 1 of every year and must cover all activities that occurred at the facility during the previous year. • The following types of facilities are required to report their activities to the EPA and the regulatory State agencies: Facilities with ten or more full-time employees that • manufacture or process over 25,000 pounds of any of approximately 600 designated chemicals or twenty-eight chemical categories specified in regulations, or • use more than 10,000 pounds of any designated chemical or category, or • are engaged in certain manufacturing operations in the industry groups specified in the U.S. Government Standard Industrial Classification Codes (SIC) 20 through 39, or • are a Federal facility. The three facilities in the City of Newport Beach listed in the Toxic Release Inventory for year 2000 (the most recent TRI data available) are summarized in Table 6-6. Earth Consultants International Hazardous Materials Management Page 6-14 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Table 6-6: Toxic Release Inventory of Facilities in the Newport Beach Area Facility Name, Address EPA 1D Chemicals Conexant Systems Int. CAD008371437 Ammonia, catechol, hydrogen (Rockwell Semiconductor Systems) fluoride, nitric acid, nitrate 4311 Jamboree Road compounds A formal enforcement action was filed by the EPA for this site on 1/29/2003. Hixson Metal Finishing CAD008357295 tetrachloroethylene 829 Production Place Raytheon Systems Company CAD057468944 Chemical names not listed. TRI (Hughes Aircraft Co.) Reportdated 2000. According 500 Superior Avenue to the City, this facility has since closed its Newport Beach location. Sources: U.S. Environmental Protection Agency, 2000, TRI On -site and Off -site Reported Releases in Orange County, California; List of EPA -regulated Facilities in Envirofacts (http://oaspub.gov/enviroQ. 6.4.4 Resources Conservation and Recovery Act The Resources Conservation and Recovery Act (RCRA) is the principal Federal law that regulates the generation, management, and transportation of hazardous materials and other wastes. Hazardous waste management includes the treatment, storage, or disposal of hazardous waste. Treatment is defined as any process that changes the • physical, chemical, or biological character of the waste to make it less of an environmental threat. Treatment can include neutralizing the waste, recovering energy or material resources from the waste, rendering the waste less hazardous, or making the waste safer to transport, dispose of, or store. Storage is defined as the holding of waste for a temporary period of time. The waste is treated, disposed of, or stored at a different facility at the end of each storage period. Disposal is the permanent placement of the waste into or on the land. Disposal facilities are usually designed to contain the waste permanently and to prevent the release of harmful pollutants to the environment. The EPA lists the following four transporters of hazardous waste in the Newport Beach area: • Innovative Waste Control, Inc. —1300 Bristol Street N., Suite 100 • R.E. Mockett-1601 Antigua • Roadway Construction Company Inc. — 4101 Westerly Place, Suite 101 • W B R Transportation, LLC — 2240 Newport Boulevard Transportation of hazardous materials on the portions of the freeways and major roads that extend through the City is most likely also conducted by other companies that are not based out of Newport Beach. • Earth Consultants International Hazardous Materials Management Page 6-15 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Many types of businesses can be producers of hazardous waste. Small businesses like dry cleaners, auto repair shops, medical facilities or hospitals, photo processing centers, and metal -plating shops are usually generators of small quantities of hazardous waste. Small -quantity generators are facilities that produce between 100 and 1,000 kilograms (Kg) of hazardous waste per month (approximately equivalent to between 220 and 2,200 pounds, or between 27 and 275 gallons). Since many of these facilities are small, start-up businesses that come and go, the list of small -quantity generators in a particular area changes significantly over time. Often, a facility remains, but the name of the business changes with new ownership. For these reasons, small -quantity generators in the Newport Beach area are not listed in this report. As of December 2002, there were approximately 115 small -quantity generators of hazardous materials in the Newport Beach area (htt�•//oaspub epa gov/enviro - search for small quantity generators under the RCRA Info database). • Larger businesses are sometimes generators of large quantities of hazardous waste. These include chemical manufacturers, large electroplating facilities, and petroleum refineries. The EPA defines a large -quantity generator as a facility that produces over 1,000 Kg (2,200 pounds or about 275 gallons) of hazardous waste per month. Large - quantity generators are fully regulated under RCRA. The large -quantity generators in the City of Newport Beach registered in 1999 and more recently are listed in Table 6-7. Table 6-7: EPA -Registered Large -Quantity Generator (LQG) Facilities in Newport Beach Facility Name, Address EPA ID RCRA Tons Generated 1 Conexant Systems, Inc. CAD008371437 2051.28 m (Rockwell Semiconductor Systems) reported as a LQG in 4311 Jamboree Road 1999 and 2000 t;Raytheon Systems Company* CAD057468944 16.91 500 Superior Avenue wNewport Fab LLC CAR000113233 Not Avallable 4311 Jamboree Road, Bldg. 503 I RCRA Notified in 2002 Sources: List of Large Quantity Generators in the United States: The National Biennial RCRA Hazardous Waste Report (Based on 1999 Data); and m List of EPA -Regulated Facilities in Envirofacts (hupY1www.epa.gov/enviro/) * The Raytheon Systems Company has since closed its Newport Beach facility, and the site has been redeveloped into a business park (Alford, personal communication, 2003). In addition to the facilities listed in Table 6-7 above, the following businesses and facilities in Newport Beach have been reported as large quantity generators in years prior to 1999: Ford Motor Company — 1000 Ford Road — reported as a large quantity generator in 1996 and 1997; Hixson Metal Finishing — 829 Production Place — reported as a large quantity generator inspected by EPA in 1996; Hoag Memorial Hospital — 301 Newport Boulevard — reported as a large quantity generator in 1997; Earth Consultants International Hazardous Materials Management Page 6-16 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Jetronic Industries In., - Transchem Division — 3767 Birch — reported as a large quantity generator inspected by EPA in 1996; The KolI Company KCN 4 — 4910 Birch Street — reported as a large quantity generator in 1996; Loral Aeronutronic — 1000 Ford Road Buildings 1, 2, 9, & 11 — reported as a large quantity generator in 1996; Newport Enterprises DBA Land Rover — 1540 Jamboree Road — reported as a large quantity generator in 1996; and Sterling Motors Ltd., DBA Sterling BMW — 3000 West Coast Hwy. — reported as a large quantity generator in 1996. As reported elsewhere in this document, some of these businesses, like Loral Aeronutronics, have since ceased their operations in Newport Beach. 6.4.5 Hazardous Materials Disclosure Program Both the Federal Government and the State of California require all businesses that handle more than a specified amount of hazardous materials or extremely hazardous materials, termed a reporting quantity, to submit a business plan to its local Certified Unified Program Agency (CUPA). The CUPA with responsibility for the City of Newport Beach is the Orange County Environmental Health Division. The Newport Beach Fire Department is listed as the local participating agency for the CUPA program. Business plans are designed to be used by responding agencies, such as the Newport • Beach Fire Department, during a release to allow for a quick and accurate evaluation of each situation for an appropriate response. Business plans are also used during a fire to quickly assess the types of chemical hazards that fire -fighting personnel may have to deal with, and to make such decisions as evacuating the surrounding areas. The Newport Beach Fire Department reviews annually submitted business plans. Business plans need to be submitted by any business that uses, generates, processes, produces, treats, stores, emits, or discharges a hazardous material in the following reportable quantities: 55 gallons of more of a liquid, 500 pounds or more of a solid, and/or 200 cubic feet or more of (compressed) gas. Any new business that meets the criteria above must submit a full hazardous materials disclosure report that includes an inventory of the hazardous materials generated, used, stored, handled, or emitted; and emergency response plans and procedures to be used in the event of a significant or threatened significant release of a hazardous material. The plan needs to identify the procedures to follow for immediate notification to all appropriate agencies and personnel in the event of a release, identification of local emergency medical assistance appropriate for potential accident scenarios, contact information for all company emergency coordinators of the business, a listing and location of emergency equipment at the business, an evacuation plan, and a training • program for business personnel. On subsequent years, once the full contingency plan is on file at the Fire Department, and if nothing has changed, businesses are allowed to Earth Consultants International Hazardous Materials Management Page 6-17 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • submit a letter stating that there are no changes to their business plan. The Fire Department conducts yearly inspections of all these businesses to confirm that their business plan is in order and up-to-date. 6.4.6 Hazardous Materials Incident Response There are thousands of different chemicals available today, each with its own unique physical characteristics; what might be an acceptable mitigation practice for one chemical could be totally inadequate for another. Therefore it is essential that agencies responding to a hazardous material release have as much available information as possible regarding the type of chemical released, the amount released, and its physical properties to effectively and quickly evaluate and contain the release. The EPA - required business plans are an excellent resource for this type of information. Other sources of information are knowledgeable facility employees present onsite. In 1986, Congress passed the Superfund Amendments and Reauthorization Act (SARA). Title III of this legislation requires that each community establish a Local Emergency Planning Committee (LEPC). This committee is responsible for developing an emergency plan that outlines steps to prepare for and respond to chemical emergencies in that community. This emergency plan must include the following: an identification of local facilities and transportation routes where hazardous materials are present; the procedures for immediate response in case of an accident (this must include • a community -wide evacuation plan); a plan for notifying the community that an incident has occurred; the names of response coordinators at local facilities; and a plan for conducting exercises to test the plan. The plan is reviewed by the State Emergency Response Commission (SERC) and publicized throughout the community. The LEPC is required to review, test, and update the plan each year. The Newport Beach Fire Department and the City Manger's Office are the City entities charged with the coordination of the City's disaster operations. 6.4.7 Hazardous Material Spill/Release Notification Guidance All significant releases or threatened releases of hazardous materials, including oil, require emergency notification to several government agencies. The State of California, Governor's Office of Emergency Services ICES) has developed a Hazardous Material Spill/Release Notification Guidance to guide the public, industry, and other government entities in the reporting process for hazardous materials accidents. This Guidance can be found at the OES website (http://www.oes.ca.govn under the Hazardous Materials Unit link. To report all significant releases or threatened releases of hazardous materials, first call 911, and then call the Governor's Office of Emergency Services (OES) Warning 00 Center at 1-800-852-7550. The City of Newport Beach has developed a Hazardous Materials Response Plan (Policy 5.17.100) that establishes the responsibility of different responding agencies to any hazardous materials release incident. The Local Authority for scene management in the event of a hazardous materials spill is the Newport Beach Earth Consultants International Hazardous Materials Management Page 6-18 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Fire Department. The Fire Department personnel that first respond to the incident make the decision to call in other agencies, depending on the situation. The Newport Beach Police Department also responds to the first call to assess whether there were any law violations or negligent acts that caused the incident, documenting the resources spent by the City for civil recovery, and documenting any exposures or injuries. Requirements for immediate notification of all significant spills or threatened releases cover: Owners, Operators, Persons in Charge, and Employers. Notification is required regarding significant releases from: facilities, vehicles, vessels, pipelines and railroads. Under Health and Safety Code §25507, State law requires Handlers, any Employees, Authorized Representatives, Agents or Designees of Handlers to, upon discovery, immediately report any release or threatened release of hazardous materials. Federal law requires, under the Emergency Planning and Community -Right -to -Know Act (SARA Title III) (EPCRA) and the Comprehensive Environmental Response, Compensation, and Liability Act (Superfund) (CERCLA), that all Owners, Operators, and Persons in Charge report all releases that equal or exceed federal reporting quantities. State law requires, at a minimum, the following information during the notification of a spill or threatened release: Identity of caller; Location, date and time of spill, release, or threatened release; • Substance and quantity involved; Chemical name (if known, it should be reported; also if the chemical is extremely hazardous); and Description of what happened. Federal law requires the following additional information during the notification of spills (CERCLA chemicals) that exceed federal reporting requirements: Medium or media impacted by the release Time and duration of the release Proper precautions to take Known or anticipated health risks Name and phone number for more information in the event of a release/spill, at a minimum, the following government agencies must be notified: Local Emergency Response agency (9-1-1 or Local Fire Department) The Certified Unified Program Agency (CUPA) (Orange County Environmental Health Division (714/667-3771) and Participating CUPA Agency (Newport Beach Fire Department, (949/644-3106) Governor's Office of Emergency Services Warning Center (1-800-852-7550 or (916/845-8911) • California Highway Patrol (CHP) (9-1-1), only if the spill/release occurred on a highway. Consultants International Hazardous Materials Management Page 6-19 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • In addition to the afore mentioned notification agencies, one or more of the following agencies may need to be notified, depending on the specifics of the incident: National Response Center (1-800/424-8802) if the spill equals or exceeds CERCLA Federal reportable quantities; United States Coast Guard (Marine Safety Office LA/Long Beach (310/732- 7380) if the spill occurred in a waterway; California Occupational Safety and Health Administration (Cal/OSHA) (Anaheim Enforcement District Office (714/939-0145) if serious injuries or harmful exposures to workers occurred during the spill; Department of Toxic Substances Control (DTSC) Cypress Regional Office (714/484-5300) if the release is from a hazardous waste tank system or from a secondary containment system; Department of Conservation, Division of Oil Gas and Geothermal Resources (DOGGR) District 1, Cypress Office (714/816-6847) in the case of an oil or gas release at a drilling site; and Public Utilities in the case of a natural gas pipeline release. For further information on the requirements for emergency notification of a hazardous chemical release, refer to the following statutes: Health and Safety Code §25270.7, 25270.8, 25507 . Vehicle Code §23112.5 Public Utilities Code §7673, (PUC General Orders #22-13, 161) Government Code §51018, 8670.25.5 (a) Water Code §13271, 13272 California Labor Code §6409.1 (b)10, and Title 42, U.S. Code §9603, 11004. • The California Accidental Release Prevention Program (CaIARP) became effective on January 1, 1997, in response to Senate Bill 1889. The CaIARP replaced the California Risk Management and Prevention Program (RMPP). Under the CaIARP, the Governor's Office of Emergency Services (OES) must adopt implementing regulations and seek delegation of the program from the EPA. The CaIARP program aims to be proactive: it requires businesses to prepare Risk Management Plans (RMPs), which are detailed engineering analyses of: the potential accident factors present at a business; and the mitigation measures that can be implemented to reduce this accident potential. In most cases, local governments have the lead role for working directly with businesses in this program. The Newport Beach Fire Department is designated as the local administering agency for this program. Earth Consultants International Hazardous Materials Management Page 6-20 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . 6.5 Leaking Underground Storage Tanks (LUST) Leaking underground storage tanks (LUSTs) are one of the greatest environmental concerns of the past several decades. In California, regulations aimed at protecting against UST leaks have been in place since 1983, one year before the Federal Resource Conservation and Recovery Act (RCRA) was amended to add Subtitle I requiring UST systems to be installed in accordance with standards that address the prevention of future leaks. The Federal regulations are found in the Code of Federal Regulations (CFR), parts 280-281. The State law and regulations are found in the California Health and Safety Code, Chapter 6.7, and the California Code of Regulations (CCR) Title 23, commonly referred to as the "California Underground Storage Tank Regulations." Federal and state programs include leak reporting and investigation regulations, and standards for clean up and remediation. UST cleanup programs exist to fund the remediation of contaminated soil and groundwater caused by leaking tanks. California's program is more stringent than the Federal program, requiring that all tanks be double walled, and prohibiting gasoline delivery to non -compliant tanks. The State Water Resources Control Board (SWRCB) has been designated the lead regulatory agency in the development of UST regulations and policy. The State of California now requires replacement of older tanks with new double -walled, tanks with flexible connections and monitoring systems. Many older tanks were single -walled steel tanks that have leaked as a result of corrosion and detached fittings. Extensive Federal and State legislation addresses LUSTs, including replacement and cleanup. UST owners were given a ten-year period to comply with the new requirements, and the deadline came due on December 22, 1998. However, many UST owners did not act by the deadline, so the State isgranted an extension for the Replacement of Underground Storage Tanks (RUST) program to January 1, 2002. The California Regional Water Quality Control Board (CRWQCB), in cooperation with the Office of Emergency Services, maintains an inventory of LUSTs in a statewide database. • According to the most recent State Water Resources Control Board's (SWRCB) Leaking Underground Storage Tank (LUST) database (dated September 25, 2002; www.swrcb.ca.gov/cwi)home/lustis/clbinfo.litn 1), 76 LUST cases were reported in the Newport Beach Area between 1982 and 2000. Of these, according to the LUST database, 47 sites have been remediated and closed, leaving 29 cases still open. These are listed in Table 6-8, below. This list however, is reportedly not updated as often as necessary, so several of the cases in Table 6-8 may be further along in the assessment and remediation process than the list indicates, and some of the cases may already be closed. This is the case with at least two leak cases, at the Newport Beach Corporate Yard and the Newport Beach Police Facility which, according to the City's General Services Director (Niederhaus, personal communication, 2003), have been released from further testing by the Orange County Health Care Agency's Environmental Division. It is also important to note that none of the leaks that have been reported in the City have impacted a drinking source of ground water. Of the cases listed in Table 6-8, fifteen impacted ground water that is not used for drinking purposes, and the rest impacted the surrounding soil only. Earth Consultants International Hazardous Materials Management Page 6-21 2003 • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Table 6-8: Leaking Underground Storage Tanks Reported in the Newport Beach Area SITE NAME ADDRESS CASE No. CASE TYPE STATUS, CONTAMINANT REPORT DATE Arco 200 Coast Hwy. 083002615T S 3A, G 28-A r-94 Beach Imports 848 Dove St. 083001608T S 3B, G 31-Jul-90 Beacon Bay Car Wash 4200 Birch St. 083001459T O 5R, G 12-A r-90 Big Canyon Country Club 1850 Jamboree Rd. 083000064T O 8, G 30-Ma -86 Chevron #20-1093 1240 Bison Ave. 083003036T S 1, G 21-Jul-97 Chevron #20-2016 2121 Bristol SL 083003460T S 1, G 99 Chevron #9-3042 1550jamboree Rd. 083000097T O SC, G Chevron #9-7100 3531 Ne ortBlvd. 083000104T O 8, G R02-Feb-8j7 Dollar Rental Car 2152 Bristol Ave. 083003725T S 1, G Edgewater Place 309 Paim St. 083000134T S SC, G Ford Aerospace Corporation 3000 Ford Rd. 083001066T S 5C, D 25-Oct-88 Four Seasons Hotel 690 Newport Center Dr. 083003073T S 3B, D 23-5 -97 Hughes Aircraft Co -Solid Prod. 500 Superior Ave. 083000821T O 7, D 02-Feb-88 Koll Center Newport (KCN A) 4910 Birch St. 083002383T S 3B, G 04-Nov-93 Lido Park Condominiums 601 Lido Park Dr. 083003306T S 1, D 10-Nov-98 Mobil #18-HG7 15o0 Balboa Blvd. 083000618T O SC, G 02-Jun-87 Mobil #18-HGK 301 Coast H . 083000246T O 5C, G 01-Au -86 Newport Auto Center 445 Coast Hwy. 083001744T O 5R, WO 21-Dec-93 Newport Beach Corp. Yard 592 Superior Ave. 083003489T S 1, G 07-Ma -99 Newport Beach Golf Club 3100 Irvine Ave. 083000295T O SR,G 01-Oct-86 Newport Beach Police De L 870 Santa Barbara Dr. 083002849T S 1, MO 25-jun-96 Newport Nissan 888 Dove St. 083000302T S 5R, UG 12 )ul-90 Permalite Plastics Corporation 1537 Monrovia Ave. 083003609T S 1, MEK 08-Oct 99 Shell #990 990 Coast Hwy. 083002129T O 5R, G 06-Jul-92 Shell #1000 1000 Irvine Ave. 083000358T O 7, G 01-Oct-86 Shell #2801 2801 Coast Hwy. 083000359T O 8, G 10-A r-85 Triangle Associates (Lub) 4625 Coast Hwy. 1183000411T O 7, G 19-Se -85 Unocal#6521 2690 San Mi uel Dr. 083000574T O 5R, G 07Jul-87 World Oil Service Station #42 3401 Newport Blvd. 083001456T O 7, H 26-Mar-90 Source: www.swrcb.ca.gov/cwRhome/lusteindex.html Abbreviations Used for Case Type: S = Soil contaminated; O = ground water not used for drinking contaminated; U = undetermined; A = drinking water aquifer contaminated. Abbreviations Used for Contaminant: G = Gasoline, UG = Unleaded Gasoline; D = Diesel, MO = Motor Oil, WO = Waste Oil; MEK= Methyl ethyl ketone. Abbreviations Used for Status: 0 = No action taken; 1 = Leak being confirmed; 3A = Preliminary site assessment workplan submitted, 36 = Preliminary site assessment underway; 5C = Pollution characterization underway; SR = Remediation plan submitted; 7= Remedial action under way; 8 = Post -remedial monitoring; 9 = Case closed / Remediation completed. Earth Consultants International Hazardous Materials Management Page 6-22 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 6.6 Household Hazardous Waste and Recycling According to FEMA (1999), most victims of chemical accidents are injured at home. These accidents usually result from ignorance or carelessness in using flammable or combustible materials. In an average city of 100,000 residents, 23.5 tons of toilet bowl cleaner, 13.5 tons of liquid household cleaners, and 3.5 tons of motor oil are discharged into city drains each month (FEMA, 1999). The County of Orange operates four household hazardous waste collection centers in accordance with the California Integrated Solid Waste Management Act of 1989 (Assembly Bill 939). These centers are located in the cities of Anaheim, Huntington Beach, Irvine, and San Juan Capistrano. The two locations closest to the City are the Huntington Beach center at 17121 Nichols Street and the Irvine location at 6411 Oak Canyon. Both locations are open Tuesday through Saturday from 9AM to 1 PM. For more information on these locations, please visit http://www.ociandfills.com/hhwcc.htm. A variety of household toxics are accepted. Acceptable wastes include batteries, cleaning products, cosmetics, latex paints, oil paint, paint in aerosol cans, fluorescent tubes with ballasts, personal care products, antifreeze, degreasers, gasoline, motor oil, unused road flares, waxes and polishes, aerosols, BBQ propane tanks, hobby chemicals, medications, varnishes, wood preservatives, and mercury. Items not accepted at these locations include ammunition, asbestos, biological waste, compressed gas cylinders, explosives, radioactive materials, and cathode ray tubes (TV and computer monitors). • 6.7 Oil Fields and Methane Gas Mitigation Districts r] Oil and gas seeps are common occurrences in many parts of California, including in and around Newport Beach. Many of California's oil fields were discovered upon drilling next to oil or gas seeps that had been flowing for centuries, if not millennia. In fact, at least 52 of California's oil fields were discovered by drilling next to seeps (California Division of Oil and Gas, 1980), and many of the area's cities started their days as oil field boom towns. Although Newport Beach does not owe its fame to oil and gas, several oil seeps and oil -stained rock in outcrops led to prospectors drilling for oil in this part of Orange County as early as 1904 (Corwin, 1946). It would take several years, until 1922, before a commercial oil field was developed in the area, but today there are two oil fields in the area: the Newport field within City limits, and the West Newport oil field within the City's Sphere of Influence. These oil fields are discussed below, and their locations are shown on Plate 6-2. Seeps still occur locally; in 1975, when the Division of Oil and Gas (now known as the Division of Oil, Gas and Geothermal Resources), surveyed the oil and gas seeps in California, six separate gas or oil and gas seeps were reported in or near Newport Beach (California Division of Oil and Gas, 1980). At least two of the oil and gas seeps were associated with a strong hydrogen sulfide odor, and in the vicinity of 43`d Street, pipes driven 2 to 3 feet into the ground had a continuous gas flow. Residents used these pipes as "tiki" torches. The City of Newport Beach recognizes several gas mitigation districts where gas can be encountered at the surface, or in the shallow subsurface. Special studies and mitigation measures are required in these areas. This will be discussed further below, in Section 6.7.2. Earth Consultants International Hazardous Materials Management Page 6-23 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Newport Oil Field —This oil field is located in the western portion of Newport Beach (see Plate 6-2). The field was divided into two areas known as the Cagney and Beach areas. The discovery well in this field was drilled in 1922 by Gilbert H. Beesemyer in the Beach Area. The well was completed at a depth of 1,750 feet, and peak production from this well was 28,946 barrels (bbl) of oil in 1925. The first well in the Cagney Area was developed by the California Exploration Co. in June 1947. This well, drilled to a total depth of 1,906 feet, had a peak production of 4,270 bbl in 1948. The deepest well in this area was developed by Jergins Oil Co. to a depth of 3,878 feet. According to the California Division of Oil and Gas (1997), the Beach Area of this field has been abandoned. As of December 2001, there were still 3 gas - producing wells in the Cagney area, and this field was estimated to have oil reserves of 35 million bbl (Division of Oil, Gas and Geothermal Resources, 2001 Annual Report). In the most recent map of the Division of Oil, Gas and Geothermal Resources (2003) only two active wells are shown in this field (see Plate 6-2). When Newport Beach adopted its charter in 1954, oil drilling was banned in the City, so no new wells will be drilled in this field. West Newport Oil Field — The West Newport Oil Field, located to the west of the older Newport Field, was discovered in April 1943, when the discovery well 'Banning" 1 was completed by D.W. Elliott to a depth of 2,404 feet. Initial production of this well was 40 bbl a day. Another well was drilled about 1,000 feet to the northeast in November 1943. This well, "Banning" 2, was completed at a depth of 2,497 feet, and produced 12 bbl of oil a day. No new wells were drilled after that until 1945. Since then, hundreds of wells have been drilled in the area, the deepest completed at a depth of 7,889 feet. At the end of 2001, there were 66 producing wells in this field, including several offshore, and 30 shut-in wells (idle but not • abandoned). At least one new well was being drilled in this field in 2002. Fifteen of the producing wells are owned by the City of Newport Beach. In 2001, the 66 wells produced 131,831 bbl of oil and condensate; and the field was estimated to have 847 millions bbl of oil in reserves (Division of Oil, Gas and Geothermal Resources, 2001 Annual Report). 6.7.1 Environmental Hazards Associated with Oil Fields Petroleum contains several components that are considered hazardous by the State of California, such as benzene, a known carcinogen. Oil field activities often include the use of hazardous materials like fuels and solvents. Day-to-day practices in some of the earlier oil fields were not environmentally sensitive, and oil -stained soils and other contaminants can often be found in and around oil fields. This typically becomes an issue when the oil field is no longer economically productive, and the property becomes a valuable real estate asset if developed, usually for residential purposes. Assessing the feasibility of developing an oil field property requires comprehensive site investigations in order to accurately identify and characterize any soil and groundwater contamination that may have resulted from the oil field operations. These site investigations are required by local and/or regional environmental laws and regulations, and vary in scope according to applicable government regulations, generally accepted standards of practice, and site -specific conditions (Fakhoury and Patton, 1992). Earth Consultants International Hazardous Materials Management Page 6-24 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Insert Plate 6-2: Oil Fields, Oil Wells and Methane Gas Mitigation Districts • • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The major areas of potential environmental concern associated with oil and gas production include: Oil spilled adjacent to oil wells: Oil -stained soil (often discolored) that occurs around oil wells and the pumping units. As can be seen by a review of the CERCLIS sites for the Newport Beach, at least one oil well site has been previously listed as a Superfund site (South Basin Oil Co. Well #1). It is possible that other well sites may need such a level of remediation prior to a change in land use. Heavy metals and oil contained in sumps pits and spill containment areas: In many oil fields, sumps were often used in the construction and maintenance of wells. Sumps are usually earthen berms constructed to contain the waste products from drilling and well completion operations. Alternatively, drilling waste materials are piped to or disposed of in metal or concrete containers. Typical waste materials consist of petroliferous cuttings, drilling fluid, additives, formation water, sludge, and crude oil. Drilling fluid typically consists of a water -based clay suspension with various chemical additives. Additives may have included any variety of heavy metals, such as arsenic, which was used as a corrosion inhibitor, or chromium and barite, which were used as weighting compounds. Wells and Cellars: Wells and cellars are often built around wells to collect oil spilled during well maintenance or equipment malfunction, but occasionally oil may spill outside the well cellar. • Oil releases from above ground and underground storage tanks: Oil -stained soils are often encountered adjacent to storage tanks. Releases may occur if a pipeline connected to the tank ruptures, if the tank itself is punctured or damaged, or during the transfer of crude between the storage tanks and transport vehicles. Released oil could impact the surrounding soils. Oil releases from broken pipelines: Buried and aboveground pipelines often exist in oil fields. These pipelines carry crude oil, water, and natural gas from the oil wells to storage tanks. A pipeline rupture would result in the release of crude oil that could impact the surrounding soils. • Spilled refined fuels used in the operation and maintenance of oil -field vehicles and generators and boneyards (disposal sites): Oil fields often have an equipment maintenance area where equipment and supplies are stored and where generators and other pumping equipment are serviced. Refined fuel (gasoline, diesel) storage tanks are often present in these areas to supply fuel for the vehicles used in servicing and maintaining the oil field. Spills of refined product can impact the soil and ground water. Refined fuels pose a greater hazard to the environment than crude oil because the lighter hydrocarbon fractions present in refined fuels are more soluble and volatile, thereby posing a greater environmental and health hazard than crude oil. Some of the constituents in gasoline and diesel fuel, including benzene, toluene, ethylbenzene and isomers of xylene, are known to be harmful to human health. Earth Consultants International Hazardous Materials Management Page 6-26 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Tank bottom material used to oil roads: Road oiling was historically a common practice in some oil fields to control dust. The oiling material was typically a residue consisting of water, oil, sediment and sludge from storage tanks. This material was sprayed on road surfaces. Formation water spilled onto the ground surface: Formation water, often containing high concentrations of total dissolved solids (approximating saline water), is often produced as part of the development of an oil field (oil wells typically produce oil, gas and water in varying quantities). If large quantities of this saline water are disposed of onto the ground surface and the water infiltrates the soil, the water quality of any near - surface aquifers could be impacted. Natural Hydrocarbon Seeps: In some oil fields, the occurrence of near -surface or at - the -surface deposits of natural tar and tar -saturated sediments, or concentrations of methane at explosive or near -explosive limits also pose a constraint to development. Both oil and gas seeps have been reported in the Newport Beach area. The potential hazards of gas (methane) are discussed further below. If these oil fields are ultimately developed into other uses, such as residential areas, those portions of the field with potential environmental concerns should be identified, and characterized by type and extent of contamination. Once established, a complete presentation of the findings, conclusions and recommendations should be done to determine risk assessments, feasibility studies and remedial action plans. The types of • concern may include: crude oil, volatile organic compounds (VOCs), semi-VOCs, metals, and polychlorinated biphenyls (PCBs). The extent of contamination is investigated by conducting site inspections, and addressing the impacts of chemical discharge to both the soil and ground water. 6.7.2 Methane Gas Mitigation Districts As briefly mentioned above, gas occurs in the shallow subsurface in some areas of the City. This gas is predominantly methane, although small amounts of many other natural gases may be part of the mix. Methane is a naturally occurring gas that typically forms as a by-product of bacterial digestion of organic matter, and therefore, occurs ubiquitously, although generally at very low concentrations, in the air we breathe. If free of impurities, methane is colorless and odorless, and under normal atmospheric conditions, does not pose a health hazard, as it is not poisonous. However, at high concentrations, this gas is flammable, and at concentration of between 55,000 and 140,000 parts per million (ppm), it is explosively combustible. At very high concentrations it can cause asphyxiation due to oxygen displacement. Methane is not toxic below levels that would lead to asphyxiation. The fact that it is colorless and odorless makes it especially hazardous, as it cannot be readily detected without special sensors. In the subsurface, methane forms in areas where organic -rich sediments, such as in a swamp, are undergoing bacterial decomposition. Because of its origin, this type of methane is referred to as "biogenic". A man-made example of such an area would be • a landfill or dairy pasture. Methane and other natural gases can also form at great depth, where they are most often associated with petroleum deposits. Since this type Earth Consultants International Hazardous Materials Management Page 6-27 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • of methane forms as a result of thermal (heat) alteration of petroleum and/or organic matter in the rocks, it is termed "thermogenic" or "petrogenic". Methane produced near the surface is generally at low to very low pressures, whereas that derived from oil -producing zones is generally at high pressures (Cobarrubias, 1992). There are numerous chemical characteristics of the gas that may reveal clues about its origin. However, the processes by which the gas forms and moves through the rocks or sediments are often very complex, altering and adding to the chemical characteristics of the gas. Consequently, it frequently becomes very difficult to determine the source. Some gases may be a combination of both thermogenic and biogenic processes. • • Regardless of the environment in which it forms, methane is lighter than air, and therefore tends to migrate upwards through permeable sediments, rock fractures, and even man-made structures (such as well casings). If the geologic unit is permeable enough, the gases eventually reach the surface and mix with the atmosphere. Under certain conditions, the gas can become trapped under an impermeable layer. In nature, these impermeable layers are typically comprised of claystone or similar fine- grained materials. As the gas accumulates under the impermeable layer, it can build up to high concentrations and pressures. Man-made structures, such as pavement or building foundations can also prevent gas from venting to the atmosphere. Methane can accumulate in the upper reaches of poorly ventilated building components, such as basements, crawl -spaces, and attics, sometimes with catastrophic results. For example, in 1986, there was a methane gas explosion and fire in the Fairfax area of Los Angeles (in the former Salt Lake oil field) that resulted from gas trapped beneath the pavement. MITIGATION OF METHANE GAS Given the potential for combustible gases to accumulate in or under buildings or structures, the City of Newport Beach has established guidelines to reduce the hazard posed by these gases. These guidelines are based on findings that show that high concentrations of methane gas can be managed and mitigated effectively with the proper investigation and analysis so that the development is protected from the adverse impacts of methane. Five methane gas mitigation districts have been identified in the City. These areas are shown on Plate 6-2. For proposed projects within these areas (project is defined as any application for tentative tract map, parcel map or zoning amendment, any construction on a previously vacant building site, or any construction that would increase the impervious surface on any parcel or parcels by 300 square feet or more), the City requires the following prior to approval of the project (City Code Chapter 15.55): Submittal of a plan prepared by a licensed consulting geologist or other qualified consultant to test for the presence of methane gas, or committal to test in conformance with the standard plans and specifications adopted by the Fire Chief and/or Building Director; Testing for the presence of methane gas in accordance with the approved plan (above) or the standard plans and specifications; Earth Consultants International Hazardous Materials Management 2003 Page 6-28 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • If testing reveals the presence of methane gas in excess of 1.25 percent by volume at ambient pressure and temperature (the lower explosive limit), submittal of a mitigation plan for approval by the Fire Chief and/or Building Director. The mitigation plan needs to be prepared by a licensed geologist or other qualified consultant. Mitigation measures that can be used include flared vent systems, underground collection systems, or other proven systems, devices or techniques. The mitigation measures proposed need to be designed to reduce the level of methane gas in any building or structure to less than 25 percent of the lower explosive limit. If the mitigation measures undertaken do not reduce the level of methane gas to below 25 percent of the lower explosive limit, the mitigation plan needs to be modified to include additional measures, and those measures need to be implemented within 30 days after approval of the amended mitigation plan. • • Installation of an isolation barrier consisting of a continuous, flexible, permanent and non -gas permeable barrier beneath all newly constructed foundations and floors at ground level. Barrier penetrations need to be secured with a gas -tight seal. Obtaining a certificate of compliance from the Fire Chief and/or Building Director in conformance with City Ordinance 89-42 §1 (part) passed in 1990. The objective of these guidelines is to prevent gases from accumulating to potentially hazardous concentrations. In the last 10 years or so, several new developments in the Newport Beach area have installed methane gas barriers to mitigate this hazard. The most complex remediation system in the area is that one in place at Hoag Hospital, in an area where the methane gas mixture includes hydrogen sulfide. The remediation system at Hoag incorporates a network of wells and trench collectors that pump the soil gases to a central unit where air scrubbers remove the hydrogen sulfide. Hoag then uses the cleaned methane to heat the building. Other features of this remediation system include a pipe -and -barrier system underneath the building slab that serves as extra guard against gas leaking through the building's foundation, and air pumps inside the building that can pull in fresh air at a rate faster than gas can come through the foundation. Therefore, should the gas sensors in the building detect seeping methane, the air pumps can bring in fresh air that would reduce the methane concentrations well below hazardous levels (http://www.laweekly.com/ink/01/24/belmont-perera3.php). Although the West Newport oil field is not located within or next to a methane gas mitigation district, if and when this field is developed for residential or other purposes, methane gas associated with the oil wells and any oil -stained soils may be encountered. The mitigation measures to be selected and implemented in this area should address oil wells in addition to natural gas seepages. The Orange County Fire Authority (OCFA, 2000) has guidelines regarding mitigation of gas leakage from abandoned wells, and mitigation procedures for buildings located near abandoned wells. The California Division of Oil, Gas and Geothermal Resources (CDOGGR), as well as the OCFA, does not approve of placing buildings directly on top of an abandoned well. Specific tasks that can be undertaken to reduce the hazard of methane gas in an abandoned oil field include: Earth Consultants International Hazardous Materials Management Page 6-29 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Baseline Study — Prior to grading, a baseline study can be performed to gain a • better understanding of the current distribution and concentrations of methane in the area proposed for development. This study can include soil gas sampling and analysis performed by a methane consultant. Since the distribution of methane can change with depth, the consultant's report should include a work plan for further investigation during grading, including sampling intervals, procedures, and potential mitigation measures that might be implemented during grading. Excavation Sampling — During grading, soil gas sampling and analysis should be performed on the bottom of all excavations in the development area. This would include cuts to design grade, overexcavation of building pads, the bottoms of areas where unsuitable foundation soils have been removed, buttress cuts, etc. "Bottoms" sampling should also be conducted at each well location. The sampling and analysis should include a determination of gas pressure, hydrocarbon concentration, and chemical composition. If anomalous, and potentially hazardous gas seeps are identified, the methane consultant shall recommend specific remedial measures. Evaluation of Subsurface Structures — During grading, any subsurface structures that may act as a conduit for methane gas (such as sewer lines, storm drains, subdrains, etc.) should be evaluated by the methane consultant with respect to the local conditions. The methane consultant should provide specific remedial recommendations, such as venting, as needed. • Documentation of Oil -Impacted Fill Placement — Full time monitoring of the grading activities should be provided by the environmental consultant in order to document the depth, lateral extent, and concentrations of any crude oil -impacted fills. This information should be provided to the methane consultant for evaluation and consideration in the final methane remedial recommendations. Abandoned Oil Well — All non -operational oil wells should be properly abandoned or reabandoned to conform with the current CDOGGR standards and subjected to CDOGGR inspections. During grading venting systems for abandoned oil wells should be constructed in accordance with recommendations and guidelines from the CDOGGR and the OCFA. Building placement should not be allowed directly over an abandoned well. Final Grade Soil Gas Survey — At the completion of grading, and prior to the issuance of building permits, sampling and analysis should be performed by the methane consultant at future building locations. Based on the data collected prior to, during, and at the completion of grading, the methane consultant should make final recommendations for methane mitigation during construction. The analysis and recommendations should consider the guidelines recommended by the City of Newport Beach or the Orange County Fire Authority (OCFA Guideline C-03, dated January 31, 2000) as minimum requirements. Any deviations from the guidelines should be supported by scientific evidence, and approved by the City's Fire Chief or Building Director. Earth Consultants International Hazardous Materials Management Page 6-30 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . Maintenance/Monitoring Manual — Prior to the issuance of occupancy permits, the methane consultant should prepare a manual describing the responsible parties, upkeep, monitoring program, record -keeping required, and reporting required with respect to the methane mitigation installed within the project. The report should include a map showing the locations of all monitoring wells, vents, or other pertinent structures. All methane investigations and analyses should be performed by a California registered engineer and/or geologist with demonstrated proficiency in the subject of soil gas investigation and mitigation. All methane reports, work plans, mitigation plans, and monitoring plans are subject to the review and approval of the City of Newport Beach. An independent third party review could be required at the discretion of the City. In addition to methane gas associated with oil fields, the City of Newport Beach has methane gas associated with old abandoned landfills. The Newport Terrace Landfill (also known as Newport City Dump No. 1) was owned and operated by the City of Newport Beach between 1953 and 1967 (see Plate 6-1). The landfill was developed by infilling a small canyon with construction and demolition debris, and domestic waste, including paper, cardboard, metal, glass and yard trimmings. When the landfill was abandoned, a gas ventilation system was installed along the property boundary. Then, in the early 1970s, a condominium was built along the southeast and northwest sides of the landfill. A gas extraction system to control subsurface gas migration was • installed in the 1980s, but recent evaluation of this system has shown that the system is not functioning due to potential leaks or blocks in the lines (California Integrated Waste Management Board, 2001). As a result, a gas investigation workplan has been prepared for the site, which includes extensive gas sampling and analysis to determine those areas of the condominium where gas occurs at levels above the regulatory thresholds. Based on the results of these analyses, additional mitigation measures for the site may be proposed. This case is an example of the methane gas issues associated with developments on or near old landfills. Mitigation measures for these facilities are similar to those employed in natural gas seepage areas, except that geotechnical issues associated with differential settlement of the refuse also need to be considered. In landfills where hazardous materials were accepted, far more stringent requirements apply to ensure that leachate from the landfill that may contain hazardous waste does not impact the ground water. 6.8 Hazard Analysis The primary concern associated with a hazardous materials release is the short and/or long term effect to the public from exposure to the hazardous material, especially when a toxic gas is involved. The best way to reduce the liability for a hazardous material release is through stringent regulations governing the storage, use, manufacturing, and handling of hazardous materials. The Newport Beach Fire Department and the Orange County Fire Authority observe the 2000 • version of the Uniform Fire Code (UFC), which identifies proper usage, storage, handling and transportation requirements for hazardous materials. Risk minimization criteria include Earth Consultants International Hazardous Materials Management Page 6-31 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • secondary containment, segregation of chemicals to reduce reactivity during a release, sprinkler and alarm systems, monitoring, venting and auto shutoff equipment, and treatment requirements for toxic gas releases. A list of the "Significant Hazardous Materials Sites" in the City of Newport Beach was compiled from the data reported in the sections above. With the exceptions noted below, the list includes facilities that are identified in the following State and/or Federal databases: Superfund-Active or Archived Sites (CERCLIS) RCRA/RCRIS-EPA Registered Large Quantity Generators Toxic Release Inventories (TRIs) Given that the two sites in Newport Beach still on the Superfund list have been archived and deemed to no longer pose a threat to the environment, they have not been included in the list of Significant Hazardous Sites. Furthermore, and more importantly, the lists included in this report are snapshots in time, and are often based on EPA data that date back to the late 1990s. Facilities that use, store, generate or transport hazardous materials are expected to come and go; so these lists, or comparable lists, should be updated at least once a year as the data become available. In fact, several facilities that in the 20"' Century used to generate, use or store hazardous materials in the City have now closed their plants, and those facilities have now been redeveloped into other, cleaner uses. The "Most Significant Hazardous Waste Sites in Newport Beach are listed in Table 6-9, and their locations are shown on Plate 6-1. Table 6-9: Significant Hazardous Materials Sites in Newport Beach Facility Name Facility ID Source Hixson Metal Finishing CAD008357295 TRI (2000) 829 Production Place Conexant Systems Inc. LQG (1999-2000), TRI (2001) 311 Jamboree Road CAD008371437 Formal EPA Enforcement Action 1/29/2003 Newport Fab LLC CAR000113233 311 Jamboree Road, Bldg. 503 LQG (2002) Abbreviations: TRI = Toxic Release Inventory; LQG = Large Quantity Generator 5.8.1 Hazardous Materials Releases as a Result of the Northridge Earthquake Isolated unauthorized releases of hazardous materials can occur at any time, but earthquakes have the potential to cause several incidents at the same time, generating worst -case scenarios for emergency response personnel. Strong seismic shaking can lead to the release of hazardous materials by damaging storage facilities and transport infrastructure. During an earthquake, chemical storage tanks could buckle, or if improperly secured and fastened, could easily be punctured and/or tipped over. Improperly segregated chemicals could react forming a toxic gas could. Pipelines are especially vulnerable to damage as they can be pulled apart or ruptured by strong ground shaking. Natural gas lines pose a significant hazard due to the high number of pipes in urban environments and because gas leaks from ruptured lines can lead to secondary fires. . Earth Consultants International Hazardous Materials Management Page 6-32 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • As a result of the Northridge earthquake, 134 locations reported hazardous materials problems and 60 emergency hazardous materials responses were required. The majority of these events occurred where structural damage was minimal or absent (Perry and Lindell, 1995). The earthquake caused 1,377 breaks in the natural gas piping system and half a dozen leaks in a 10-inch crude oil pipeline (Hall, 1994). The 1987 Whittier Narrows earthquake, a significantly smaller event than the Northridge earthquake, caused 22 hazardous materials situations, including the collapse of a chlorine tank that forced the evacuation of an area in Santa Fe Springs. The Whittier Narrows earthquake also caused over 1,400 natural gas leaks, three of which caused subsequent fires. A key point to remember regarding the management of hazardous materials spills in the aftermath of an earthquake is that it is substantially more difficult to do so than under non -earthquake conditions. Hazardous materials response teams responding to a release as a result of an earthquake have to deal with potential structural and non- structural problems of the buildings housing the hazardous materials, potential leaks of natural gas from ruptured pipes, and/or downed electrical lines or equipment that could create sparks and cause a fire. When two hazards with potentially high negative consequences intersect, the challenges of managing each are greatly increased. During an earthquake response, hazardous materials emergencies become an additional threat that must be integrated into the response management system. • 6.8.2 Hazards Overlays Plate 6-1 was used as an overlay to the other plates prepared for this Hazard Evaluation Study for the City of Newport Beach to assess the natural hazards vulnerability of the significant hazardous materials sites. The intent was to identify whether some of these sites are located in areas at risk of being impacted by the natural hazards discussed in other chapters. This analysis indicates that none of the Significant Hazardous Materials sites are located within or near the Fault Hazard Management Zone proposed for the Newport -Inglewood fault. Nevertheless, the entire City is susceptible to strong to very strong ground motions due to its location relative to the Newport -Inglewood and San Joaquin Hills faults. Due to the large quantities of hazardous materials used at the Significant Hazardous Materials facilities, strong ground shaking poses a special concern that needs to be addressed. Proactive management of these hazardous substances, to levels far beyond the required standards should be considered. None of the Significant Hazardous Materials sites are located within a liquefaction susceptible area, or in the 100-flood zone. The City of Newport Beach has approximately nineteen schools. Two schools are located within one mile of one of the Significant Hazardous Materials Sites in the northwest portion of the City. Hoag Memorial Hospital is also located within one mile of this site. The Toxic Release Inventory sites are of most concern in this regard, since emissions into the air have the potential to impact a large geographical area. If any of the chemicals used at this facility are toxic when released into the atmosphere, • evacuation of the surrounding area may be required. The Toxic Release Inventory for the Hixson Metal Finishing facility reports the use of tetrachloroethylene. This is a Earth Consultants International Hazardous Materials Management Page 6-33 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • manufactured chemical that is widely used in the dry-cleaning industry, for metal degreasing, and in the manufacturing of other chemicals and consumer products. In a poorly ventilated area, release of this chemical onto the air can pose a health hazard, but when released into a ventilated area, such as the surrounding neighborhood, the chemical is broken down by sunlight, or brought back to the soil and water by rain (http://www.atsdr.cdc.gov/tfactsl8.htmq, greatly reducing its health hazard. A greater concern is posed by the chlorine gas used at Big Canyon Reservoir, especially given that there are three schools located very close to the reservoir. As discussed in Section 6.3, chlorine gas is highly toxic, and since it is heavier than air, it tends to stay close to the ground, where it has a greater likelihood of impacting the surrounding population. Chlorine gas detectors, secondary containment systems and the continual operation of scrubbers or other treatment systems to neutralize the chlorine before the gas is vented can all be used to reduce the adverse impacts of an accidental release of chlorine. The potential impact to the surrounding community is expected to be greatly reduced in 2004, when the reservoir will be covered, and liquid chlorine, instead of chlorine gas, will be used as the water disinfectant. Liquid chlorine will also be used at San Joaquin Reservoir once the Irvine Ranch Water District starts using it as a reclaimed water storage facility. There are two schools located near this facility. Although liquid chlorine is less likely to pose a hazard to the surrounding areas, it is still an unstable substance, especially if allowed to come in contact with acids. Proper maintenance, storage and usage procedures should be utilized at all times. • Since schools and hospitals have special evacuation needs, Significant Hazardous Material facilities should be required to prepare Risk Management Plans (RMPs) that identify the procedures by which the surrounding critical facilities will be evacuated, should it become necessary during an accidental release of hazardous materials. Similar mitigation measures should be considered for other facilities where the populations have special evacuation needs, such as nursing homes and child care centers. The two other significant hazardous materials sites are located at or near the City's boundaries. Several of the chemicals reportedly used at Conexant Systems are toxic gases that could impact the surrounding population if released onto the environment. Critical facilities not identified herein because they are outside the City, in surrounding communities may be located within a short distance of these hazardous materials sites. The Risk Management Plans prepared by these facilities should address all critical facilities within a given radius, such as 1/2-mile or 1-mile from the hazardous materials site, so as to identify potential impact areas not within City limits. 6.9 Summary of Findings and Natural Hazards Overlays The primary concern associated with a hazardous materials release is the short and/or long term effect to the public from exposure to the hazardous material. The best way to reduce the liability for a hazardous material release is through stringent regulation governing the storage, use, manufacturing and handling of hazardous materials. These regulations are typically issued • by the EPA, but various local agencies are tasked with the responsibility of monitoring those facilities that use, storage, transport, and dispose hazardous materials for compliance with the Earth Consultants International Hazardous Materials Management Page 6-34 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Federal guidelines, or if applicable, with more stringent State guidelines. Some of these programs and regulations, and the local enforcement agency, are summarized below, as they pertain to the City of Newport Beach. 6.9.1 Summary of Findings Air Quality: Data from the South Coast Air Quality District for the year 2001 show that the ozone levels were above the Federal standards for only one day that year in the North Coastal Orange County area, which includes the City of Newport Beach. All other pollutants were below both Federal and State air quality standards. Air quality criteria are expected to become more stringent, however, as the results of recent studies indicate that air quality in many parts of the southern California area is still poor. Drinking Water Quality: Two water agencies provide drinking water to the Newport Beach area. The two agencies are: Orange County Water District and the Metropolitan Water District of Orange County. Neither of these agencies is listed on the EPA Safe Drinking Water Violation Report. National Pollutant Discharge Elimination System (NPDES): The City of Newport Beach is a member of the Orange County's Stormwater Program, the local administering agency for the National Pollutant Discharge Elimination System. NPDES permits in the Newport Beach area are issued by the California Regional Water Quality Control Board, Santa Ana Region. The City of Newport Beach holds a NPDES permit, • adopted January 2002, to operate its municipal separate storm sewer system (MS4). The permit requires the City to keep pollutants out of its MS$ to the maximum extent practicable, and to ensure that dry -weather flows entering recreational waters from the MS4 do not cause or contribute to exceedances of water quality standards. The City also has a stringent Water Quality Ordinance and requires the use of "best management practices" in many residential, commercial, and development -related activities to reduce runoff. Superfund Sites: According to the EPA, there are two Superfund sites in the City of Newport Beach, but neither of them is listed in the National Priority List (NPL). Furthermore, one of the sites is considered by the EPA as a "No Further Remedial Action Planned (NFRAP) site, while the other site has reportedly been cleaned up, although the EPA data is not yet reflecting this information. Given that both sites appear to no longer pose an environmental hazard to the area, they have not been included in the list of most significant hazardous sites in the City of Newport Beach. Toxic Release Inventory: According to the EPA records, there are three facilities in the Newport Beach area that are listed in the most recently available Toxics Release Inventory (TRI). One of these facilities has since closed its plant in Newport Beach. TRI sites are known to release toxic chemicals into the air. The EPA closely monitors the emissions from these facilities to ensure that their annual limits are not exceeded. The South Coast Air Quality Management District also issues permits to facilities that emit chemicals, both toxic and non -toxic, into the atmosphere. These facilities include . restaurants, hotels, dry-cleaners, and other small businesses. Earth Consultants International Hazardous Materials Management Page 6-35 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Hazardous Waste Sites: According to the most recent EPA and City data available, there are two large quantity generators and approximately 115 small quantity generators in the Newport Beach area. In addition there are four transporters of hazardous waste with offices in the City. The number of small quantity generators is expected to increase with increasing development in the City, since this list includes businesses like gasoline stations, dry cleaners, and photo -processing shops. • • Leaking Underground Storage Tanks: According to data from the State Water Resources Control Board, 76 underground storage tank leaks have been reported in the Newport Beach area. Of these, according to the State list, 47 sites have been either cleaned up or deemed to be of no environmental consequence, leaving 29 cases that are still open and in various stages of the remediation process. Information provided by the City, however, suggests that some of the cases still on the State list have already been closed. None of the leaks that have been reported in the City have impacted a drinking source of ground water. The Orange County Environmental Health Department provides oversight and conducts inspections of all underground tank removals and installation of new tanks. Hazardous Materials Disclosure Program: Both the Federal government and the State of California require all businesses that handle more than a specified amount of hazardous materials or extremely hazardous materials to submit a business plan to a regulating agency. Business plans are currently reviewed by the Newport Beach Fire Department, who also conducts annual on -site reviews of permitted businesses to confirm that the information in their business plans is current and correct. Household Hazardous Waste: The County of Orange operates four household hazardous waste collection centers in accordance with the California Integrated Solid Waste Management Act of 1989 (AB 939). These centers are located in the cities of Anaheim, Huntington Beach, Irvine, and San Juan Capistrano. The two locations closest to the City are the Huntington Beach center at 17121 Nichols Street and the Irvine location at 6411 Oak Canyon. Oil Fields: There is one oil field in the City of Newport Beach and one in its Sphere of Influence. Hazardous materials are often associated with these facilities, usually as a result of poor practices in the early days of exploration, when oil cuttings, brine water, and other by-products were dumped onto the ground. The development of oil fields for residential or commercial purposes typically involves a detailed study to identify any areas impacted by oil or other hazardous materials, and the remediation of the property prior to development. Methane Gas Mitigation Districts: Natural seepages of gas occur in the western and southwestern portions of the City. Methane gas associated with an abandoned landfill has also been reported near the City's northwestern corner. The City has implemented a series of mitigation measures to reduce the hazard associated with methane gas. Continuous implementation of these guidelines is recommended. Earth Consultants International Hazardous Materials Management Page 6-36 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 6.9.2 Hazards Overlays The City of Newport Beach is a vital economic and residential region, where, especially in the older sections of the City, businesses and residential areas are often within short distances of each other, or they co -exist. This gives the City a strong sense of community, a quality unique to only a few areas of southern California. Most "planned" communities that have sprung elsewhere in the last decades do not provide for this desirable mix of uses within short, walking distances of each other. Unfortunately, there are also some disadvantages to this zoning plan - facilities that generate, use, or store hazardous materials are often located near residential areas or near critical facilities, with the potential to impact these areas if hazardous materials are released into the environment at concentrations of concern. There are two large -quantity and more than one hundred small -quantity generators of hazardous materials in the City. Given these numbers, it is impressive that the actual number of unauthorized releases of hazardous materials into the environment is fairly small, as documented in the Federal and State databases reviewed. There are two active sites that are known to release toxic chemicals into the air — the EPA monitors these facilities closely to reduce the potential of future emissions at concentrations above the acceptable limits. Strong ground shaking caused by an earthquake on one of the many faults in the region could cause the release of hazardous materials at any of the hazardous materials facilities in the City. Therefore, all sites should provide for, at a minimum, secondary • containment of hazardous substances, including segregation of reactive chemicals, in accordance with the most recent Uniform Fire Code. None of the significant hazardous materials sites are located within or next to the proposed Fault Hazard Management Zone for the Newport -Inglewood fault, or within a liquefaction -susceptible or flooding hazard area. • Earth Consultants International Hazardous Materials Management 2003 Page 6-37 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • References California Integrated Waste Management Board, 2001, Final Draft, Gas Investigation Workplan for the Newport Terrace Landfill/Condominium, City of Newport Beach, Orange County: SWIS #30-CR-0127, dated March 7, 2001. California Division of Oil and Gas, 1980, Onshore Oil and Gas Seeps in California: Publication No. TR26, Text by Susan F. Hodgson, 97p. (re -issued in 1987). California Division of Oil and Gas, 1991, California Oil and Gas Fields Volume 2: Southern, Central Coastal, and Offshore California. California Division of Oil, Gas, and Geothermal Resources, 1997, Map No. 136. California Division of Oil, Gas and Geothermal Resources, 2001, Annual Report. Cobarrubias, J.W., 1992, Methane Gas Hazard within the Fairfax District, Los Angeles; in Pipkin, B.W., and Proctor, R.J., (editors), Engineering Geology Practice in southern California: Association of Engineering Geologists Special Publication No. 4, pp. 131- 143. Corwin, Chas H., 1946, West Newport Oil Field; in Division of Oil and Gas, California Oil Fields Summary of Operations, Vol. 32, No. 2, July -December 1946, pp. 8-15. • Federal Code of Regulations, Title 40: Protection of Environment; http://,A,ww.epa.gov/epahome/cfr4O.htni • Merck Company, 1983, The Merck Index of Chemicals, Drugs and Biologicals, 10'h Edition, Rahway, New Jersey, pp. 852-853. Orange County Fire Authority (OCFA), 2000, Guideline for Combustible Soil Gas Hazard Mitigation, Guideline C-03, dated January 31, 2000. South Coast Air Quality Management District, 2001, Current Air Quality and Trends in the South Coast Air Quality Management District, 2000 Air Quality Standards Compliance Report, Vol. 13, No. 12, 10p. (obtained at www.agmd.gov). Earth Consultants International Hazardous Materials Management Page 6-38 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • CHAPTER 7: AVIATION DISASTERS HAZARDS & POTENTIAL IMPACTS CAUSED BY AIR TRAFFIC ON THE CITY OF NEWPORT BEACH, CALIFORNIA • Prepared by Gunnar J. Kuepper @ for Earth Consultants International Emergency & Disaster Management 5959 West Century Boulevard, Suite 501 . Los Angeles, CA 90045 Ph: (310) 649 — 0700 Fax: (310) 649 —1126 w .edmus.infc HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • CHAPTER 7: AVIATION DISASTERS 7.1 Introduction and Scope of the Evaluation The City of Newport Beach seeks to assess and identify the potential for an aviation disaster within its jurisdiction, and the impact of such an event on: ➢ the health and safety of persons in the affected area and responding to the incident; ➢ property, facilities, and infrastructure ➢ the environment ➢ local businesses and the economy, and ➢ the reputation and value of the City as a whole. John Wayne Airport QWA) generates nearly all aviation traffic above the City of Newport Beach. This report illustrates the actual conditions and legal obligations of the airport and the aviation community, including the Federal Aviation Administration (FAA) and local emergency response services. After an initial overview, this report analyzes the impact of potential events that might take place within the Newport Beach City limits and might substantially affect the area. The analysis provides a clear idea of the likelihood of a major aviation accident, what areas or functions can be expected to be most seriously impacted, and what actions will most effectively protect life and safety, property, the environment, and the interests of the City. • This report does not address the risk of general aviation accidents. General Aviation (GA) is defined by the International Civil Aviation Organization (ICAO) in Annex 6 as "all civil aviation operations other than scheduled air services and non-scheduled air transport operations for remuneration or hire." The vast majority of GA planes are light, single, or twin -engine models, used mainly for recreational purposes, limited in size and seating capacity (usually 2 to 8), with a small amount of fuel carried (less than 200 gallons on average), with a typical gross weight not in excess of 12,500 pounds. A crash involving this type of aircraft, even a collision in mid -air, may account for a major incident, but does not pose the threat of a catastrophic impact. The forces and consequences of a small aircraft could be compared with a high-speed automobile accident involving numerous occupants, and should, therefore, be manageable for local emergency services. Even jets or a Boeing 747 used for private purposes can count as "general aviation" (as does Air Force One), but these larger general aviation aircraft represent only a fraction of all air traffic at John Wayne Airport. 7.2 Setting The City of Newport Beach has a population of more than 75,000 living in nearly 38,400 housing units within a land area of 25 square miles. (According to the City's website, the inland bodies of water and 23 square miles of ocean combine for a total of 50.5 square miles.) Of the housing units in the City, 19,400 (56 percent) are occupied by the owners. The median value of each of these houses is more than $700,000; the per capita income is $63,000. Newport Beach has several gated communities. • Geographically, the City can be divided into the four areas described below (see Plate 7-1): Gunnar). Kuepper Q Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-1 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 1) west of the bay (residential with mainly free-standing single-family residences, schools, and light commercial property); 2) east of the bay (free-standing residences, gated communities, and commercial areas, including Fashion Island, and high-rise office and hotel buildings); 3) north of the bay (free-standing residences in the Santa Ana Heights area, and high-rises in the Airport Area); and 4) water front property (including Newport Peninsula and Balboa Island), with a total water frontage of 31 miles (6 miles of ocean front, 25 miles of harbor front). 7.3 Orange County John Wayne Airport (JWA) 7.3.1 Overview JWA is operated as a department of the County of Orange, but is a self-supporting enterprise fund in the general financial statements of the county. It operates under the direction of the Airport Director, currently Mr. Alan L. Murphy, and an Assistant Director. It is comprised of five functional divisions (Business Development, Facilities, Finance and Administration, Public Affairs, Operations), each managed by a Deputy Airport Director. Two hundred County employees are assigned to JWA, including 54 members of the Sheriff's Department. In addition, 21 fire personnel of the Orange County Fire Authority (OCFA) are assigned to the Airport Fire Station (No. 33) that is staffed 24 hours a day, 7 days a week. • The airport is located on 500 acres, and has two runways. The commercial runway (1 V19R) has a length of 5,700 feet, and the parallel general aviation runway (19L) is 2,900 feet long (see Plate 7-2). • 7.3.2 2001 Air Operations With nearly 380,000 air operations in 2001, JWA was the 291h busiest airport in the United States. It is important to note, however, that 80 percent of these activities were attributed to general aviation. Commercial and commuter planes accounted for 95,000 starts (take -offs) and landings. Ten commercial passenger airlines (Alaska, Aloha, American, America West, Continental, Delta, Northwest, Southwest, United, US Airways) and three commuter carriers (SkyWest, America West Express, American Eagle) moved 7.32 million passengers (3.67 million enplaned; 3.65 million deplaned). Also in 2001, 16,100 tons of air cargo were processed, primarily via FedEx and UPS planes. According to reports published by Orange County, JWA generates more than $3.5 billion each year for the local economy, including 57,000 direct or indirect jobs. Personnel directly employed at JWA facilities or by airport service providers number 2,500. It is important to note that the income and revenue stream for the City of Newport Beach seems not to rely significantly on airport and aviation business. Gunnar J. Kuepper B Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-2 • NOTES This map is intended for general land use panning only Information on this map is not suRciont to serve as a substitute for detailed geologic investigations of Individual sites, nor does t satisfy the evaluation requirements set forth In geologic hazard regulations. Earth Consultants International (ECI) makes no representations or warranties regarding the accuracy of the data from which these maps were derived. ECI shall not be liable under any circumstances for any direct, indirect, special. incidental, or consequential damages voth respect to any claim by any user or third party on account of, or arising from, the use of this map. Santa Ana Heights '•, UpperNewpor[jw j Bay 1 < Fashion Island ♦•\ Balboa Island ngu/a % �.��♦ a 1' r 1 1 Geographic Areas of Newport Beach Near John Wayne Airport Mentioned in Text EXPLANATION Newport Beach City Boundary Sphere of Influence Scale: 1:72,000 1 0 1 2 3 -Kilo neters 0.5 0 0.5 1 1.5 Miles Base Map: USGS Topographic Map from Surelli RASTER Earth Consultants = International Project Number: 2112 '. Date: July, 2003 Plate 7-1 C] Fuel r General General Aviation FBO Facilities Aviation Fire Parking I Parking Station Control Tower ild lut T Hangers�jj / FBO -Eac lities r ,� T Hangers �i FBO Facilities Helicopter Parking Area � Mac grthur lvd Diagram of John Wayne Airport Showing Runways and Facilities EXPLANATION SYMBOLS = Runway _ Buildings / Structures Not to Scale Modified from John Wayne Airport Website www.ocari.com/images/Airfield_ layout_map.gif Consultants International Project Number: 2112 Date: March, 2003 Plate 7-2 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 7.3.3 Future Air Operations An existing noise abatement program and a federal court settlement signed in 1985 by the County of Orange, the City of Newport Beach, the Airport Working Group, and Stop Polluting Our Newport limits the number of passengers and departures until December 31, 2005. The City has reached an agreement with the County to extend the settlement agreement through 2015. Under the amended settlement agreement, after January 1, 2003, the annual passenger limit can increase to 9.8 million; the daily number of noise - regulated passenger flights can increase to 85; and the daily number of cargo flights can increase to 4. Due to JWA's relatively short runway length of 5,700 feet (in comparison to Los Angeles International Airport (LAX] and other airports accommodating large airplanes on runways 12,000 feet long), it is highly probable that the size of future airplanes at John Wayne Airport will be limited to short- and medium -range airliners. The airport is open 24 hours a day, 7 days a week. Air carrier operations are limited to between 7 A.M. and 10 P.M. (11 P.M. for arrivals) Monday through Saturday, and 8 A.M. to 10 P.M. (11 P.M. for arrivals) on Sundays. The air traffic control tower is operational from 6:15 A.M. to 11 P.M. daily. 7.3.4 Departure Route Due to the noise abatement program in place, all commercial airplanes departing JWA • using runway 1 L are required to: • ➢ follow the course of the Newport Bay, ➢ make an initial steep climb using full power until the plane has reached an altitude of 800 to 1,000 feet, and ➢ continue to climb with reduced power (half -throttle) until the coast line is reached, which is usually at an altitude of 2,200 to 2,500 feet (see Plate 7-3). This procedure may not be considered a difficult or risky maneuver. It is easily handled by modern airplanes. Should pilots encounter any kind of difficulties or problems, however, they can abandon the designated take -off route at any time and proceed as the situation mandates. 7.3.5 Airport Fire Rescue Services (ARFF or CFR) The airport is protected by an on -site airport fire service as required by FAA regulations. This service is provided by Orange County Fire Station No. 33, which is staffed 24 hours a day, seven days a week, with a minimum of seven firefighters at any given time. Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-5 • • • NOTES This map is irtended for general land use planning only. Information on this map is not suPiciont to serve as a subshtuto for detailed geologic investigations of individual sites, nor does I satisfy the evaluation requirements set forth In geologic nerd regulations. Earth Consultants International i makes no reoresentaticns or warranties regarding the accuracy of the date from which these maps were derived ECI shall not be liable under any circumstances for any direct, indirect, special, incidental, or consequential damages wdh respect to any claim by any user or third parry or account of, or alls ng from, the use of this map. John Wayne Airport (Santa Ana Airport) Air Traffic Routes Above Newport Beach, California EXPLANATION Arrival Path (rare)-- most airplanes arrive from the north 7► Departure Path Newport Beach City Boundary Sphere of Influence Scale: 1:72,000 1 0 1 2 3 Kilometers 0.5 0 0.5 1 1.5 Miles Base Map: USGS Topographic Map from Sure! MAPS RASTER Earth A— Consultants Internafanal Project Number: 2112 Date July, 2003 Plate 7-3 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The Orange County Fire Station No. 33 maintains the following equipment: ➢ Oshkosh 3000 (Crash 1) ➢ Oshkosh 1500 (Crash 2) ➢ Oshkosh 1500 (Crash 3) ➢ Walter 1500 (Crash 4) — relief vehicle. Unfortunately, these Aircraft Rescue Fire Fighting (ARFF) units are not yet outfitted entirely with state-of-the-art equipment, such as elevated water booms with penetrating nozzles. These devices fitted atop an ARFF vehicle are used to penetrate the outer skin of an airplane and spray cooling water or foam directly into the cabin. This procedure reduces the temperature and provides the occupants with a more survivable atmosphere and increased time to evacuate. The author was assured that specifications for a new vehicle (Oshkosh 3000) have been submitted, and the new equipment is expected within the next two years. The primary objective of the airport fire service is to provide fire protection for the airfield. ARFF units will respond to: 1) airplane crashes on airport property 2) airplane crashes within one mile of the airport (only if in doing so the airport does not fall below Index C required ARFF protection OR if approved by the Airport Director'). The described 1-mile radius will cover only the northern part of • Newport Beach. According to Part 139.315 of Title 14 of the Federal Aviation Regulations (FAR), an Index for Airport Fire Rescue Services exists for each certificate holder (airport). The Index is determined by a combination of: (1) The length of air carrier aircraft expressed in groups; and (2) Average daily departures of air carrier aircraft. For the purpose of Index determination, air carrier aircraft lengths are grouped as follows: (1) Index A includes aircraft less than 90 feet in length (i.e., Bae 146, Saab 340 B and 2000); (2) Index B includes aircraft at least 90 feet but less than 126 feet in length (i.e., Boeing 737-300, Airbus A320-200); (3) Index C includes aircraft at least 126 feet but less than 159 feet in length (i.e., Boeing 757-200, MD-87); (4) Index D includes aircraft at least 159 feet but less than 200 feet in length (i.e., Airbus A340-200, Lockheed L-1011- 500 Tristar); (5) Index E includes aircraft at least 200 feet in length (i.e., Boeing 747, Boeing 777-200, Airbus A330-300, MD-1 1). The Index required is determined as follows: (1) For five or more average daily departures of air carrier aircraft in a single Index group serving an airport, the longest Index group with an average of five or more daily departures is the Index required for the airport. (2) If there are fewer than an average of five daily departures of air carrier aircraft in a single Index group serving an airport, the next lower Index from the longest group is the Index required for the airport. The minimum designated Index shall be Index A. According to Part 139.317, an Index C airport must provide either: (1) THREE ARFF vehicles (One carrying at least 500 pounds of sodium -based dry chemical or halon 1211, or 450 pounds of potassium -based dry chemical and water with a commensurate quantity of AFFF (Aqueous Film Forming Foam) to total 100 gallons, for simultaneous dry chemical and AFFF application, plus Two vehicles carrying an amount of water and the commensurate quantity of AFFF, so that the TOTAL quantity of WATER for foam production CARRIED BY ALL THREE VEHICLES is at least 3,000 gallons); OR (2) TWO ARFF vehicles (One carrying at least 500 pounds of sodium -based dry chemical or halon 1211, AND 1,500 gallons of water, and the commensurate quantity of AFFF for foam production, plus One vehicle carrying water and • the commensurate quantity of AFFF so that the TOTAL quantity of WATER for foam production carried by BOTH VEHICLES is at least 3,000 gallons). The minimum requirement of ARFF personnel is one (driver) for each vehicle. Gunnar). Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-7 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIEORNIA • figure 7-1: Image Shows the Steep Ascent of a Passenger Jet Taking Off from JWA • figure 7-2: Crash 1 & 2 During the September 1998 Exercises at JWA r7 Airliners departing from JWA carry a significant load of fuel. When a jet or turboprop plane crashes on take -off, the force of the impact will rupture components of the fuel system. Numerous ignition sources (i.e., sparks caused by friction, electrical short circuits, hot engine components) will initiate a major fuel fire. . Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-8 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Local fire services use water to extinguish fires in day-to-day operations, but water is generally not suitable for large liquid fuel (Class B) fires. Instead, foam or dry chemicals must be used to contain and extinguish the flames, and to allow for the evacuation and rescue of survivors. The large quantities of foam needed in such an event are carried on the ARFF vehicles stationed at JWA. These units may be the only way to successfully save lives threatened by smoke, -heat, and fire. In the event of a fiery crash into Balboa Island or other areas with dense buildings, the immediate response of ARFF units will be critical. However, the Newport Beach harbor and island areas are located four to five miles south of JWA, outside the pre -designated operational area (limited to airport property or the one -mile radius surrounding the airfield). 7.4 Airplanes Operating at John Wayne Airport QWA) JWA is designated by the Federal Aviation Administration (FAA) as an Index C airport (see footnote in Pages 7-7 and 7-8). As mentioned before, the airport is open 24 hours a day, 7 days a week, but commercial departures are restricted to between 7 A.M. and 10 P.M. Monday through Saturday, and between 8 A.M. and 10 P.M. on Sunday. Arrivals are allowed until 11 P.M. On an average business day, 150 commercial and 20 regional flights arrive at and depart from • JWA. Among the airplanes most often used by passenger and cargo carriers (airlines) at JWA are the following: ➢ Airbus A 319/320: up to 179 passengers ➢ Boeing 737 (Version 200, 300, 400, 500, 700 and 800): up to 239 passengers (fuel capacity 6,800 gallons) ➢ Boeing 757 (Version 200): up to 239 passengers (fuel capacity 11,500 gallons) ➢ Boeing 757 F (Freighter Version) ➢ MD 80: up to 130 passengers ➢ MD 90: up to 187 passengers All of the planes listed above are short- to medium -range airliners and belong to the current generation of aircraft. (See examples for aircraft dimensions and ARFF references in the appendix). The only airplane larger than those above is an ➢ Airbus A 310 Freighter: operated once a day by FedEx. This airplane can carry up to 55 tons of cargo (see risk of • cargo planes). Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-9 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA 7.5 Airplane Crashes 7.5.1 Probability and Location Accidents with one or more fatalities involving commercial aircraft are rare events. On average, 40 planes crash in any given year throughout the world, causing approximately 1,000 fatalities. Given the size of the United States' surface (9.63 million square miles), the number of commercial plane crashes within the country in any given year (less than 10), and the size of Newport Beach (50.5 square miles), the statistical risk comes to 1 in 20,000 per year. The risk of any given community being hit by an airplane disaster is extremely low, and probably a one -in -one -hundred -years or more event. The current accident rate, particularly for United States and Canadian operators, is less than 0.5 per million departures. However, 75 percent of all air carrier accidents occur on or in the vicinity of an airport, usually within a 3- to 5-mile radius of the runway threshold. According to a survey by the Air Line Pilots Association (ALPA), the vast majority of these accidents occur within 2,000 feet of the runway threshold and within 500 feet of the runway centerlines. The City of Newport Beach borders the southeastern portion of JWA. More than 95 percent of all airplanes take off and climb over the City (see Plate 7-2). Although this increases significantly the risk of an accident within the City limits, statistically the risk is still very low. Of the air carrier accidents that occur in the vicinity of an airport (which are 75 • percent of an average of 40 per year, worldwide), one-third may happen on landing approach, one-third on airport property, and one-third on take -off or in a runway -overrun situation. In 1970, the County of Orange established an Airport Land Use Commission (ALUC). Its key duties are to prepare and adopt an airport land use plan and to review plans, regulations, and other actions of local agencies and airport operators. The commission, however, has no jurisdiction over any airport operations. The ALUC issued final draft of the Airport Environs Land Use Plan (AELUP) for John Wayne Airport on December 10, 2002. The scope and purpose of the document is: ➢ to safeguard the general welfare of the inhabitants within the vicinity of the airport, which includes that people and facilities are not concentrated in areas susceptible to aircraft accidents, and ➢ to ensure continued airport operations, which includes that no structures or activities adversely affect navigable airspace. Section 2.1.2 of the plan describes the ALUC's task to designate Accident Potential Zones (APZs) around civil airports. The Commission stated that data had been evaluated from all airport accidents in California and at each civilian airport in Orange County, and concluded that there was insufficient evidence to identify crash hazard zones applicable to all airports. Gunnar J. Kuepper Q Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-10 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • The Airport Environs Land Use Plan (AELUP) contains in Appendix D a map entitled John Wayne Airport Impact Zones, which displays Runway Protection Zones (RPZ). Again, the Commission has not adopted these Accident Potential Zones for JWA, as none could be justified with the available data. The author disagrees with this particular conclusion. As discussed in Section 7.5.2 below, potential accident areas, probability, and impacts can be assessed based on multiple factors described in this Hazard Assessment Study. The map of JWA Impact Zones in Appendix D of the AELUP is largely consistent with the findings in this study. The RPZ (Runway Protection Zone) is the imaginary extension of runway 19R/1 L in both directions. As described in Section 3.2.5 of the AELUP, it allows only for airport -related and open space uses (agriculture, transportation, etc.), and prohibits buildings intended for human habitation. Such a requirement, even if not adopted by the Commission, is satisfied in the southern vicinity of the JWA (Newport Beach). It covers the unpopulated open space of the Newport Beach Golf Course. The next area is described as Accident Potential Zone I (Section 3.2.6 of the AELUP). It allows for open space, commercial, industrial, and airport -related uses as long as lot coverage does not exceed 50 percent, and no more than 100 persons occupy any single building for an extended period of time. Residential use and places of indoor or outdoor assembly (i.e., churches, schools, restaurants, conference facilities) should not be allowed in this area. This APZ covers the Newport Beach Golf Course leading into the uninhabited Upper Newport Bay. The area described as Accident Potential Zone II in Section 3.2.7 of the AELUP covers the unpopulated Upper Newport Bay area. Airplane accidents are primarily caused by three factors: human error, technological failure, and adverse weather (or a combination thereof). JWA and the City of Newport Beach are located in southern California and, therefore, rarely experience heavy or adverse weather conditions. Most states and countries throughout the world see frequent snowstorms and rainstorms, high winds, reduced visibility, etc., but these conditions are rather unusual at JWA. In addition, airplanes that experience technical malfunctions (i.e., landing gear that does not extend) are usually diverted to nearby Los Angeles International Airport (LAX). LAX provides four runways with a length of 12,000 feet each and maintains the sophisticated fire and rescue equipment appropriate for an Index E airport. The exact location and time of an airplane accident cannot be predetermined. Taking all the above facts into consideration, it may be safe to say that the crash of a commercial airplane within the City of Newport Beach will be a 25- to 40-year event. (Statistically, at this time, it is a 41-year event.) The probability of an airplane accident also depends on the age and model of the aircraft. According to a Boeing study, the first models of every new generation of airplanes are at higher risk (due in part to undetected flaws and the lack of pilot familiarity). Obviously, aging airplanes (at least those older than 22 years) face an increased, if not exponentially increased, risk of accident. Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-11 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • As part of a mitigation effort to prevent or reduce the risk of aviation disaster, the City of Newport Beach might choose to steer JWA towards limiting landing and departure rights to commercial airplanes not exceeding a specific age. 7.5.2 Impact and Vulnerability Any major plane crash has the potential for a catastrophic outcome. In addition to the loss of life aboard the plane (up to 200), such an event can cause casualties and devastation on the ground (i.e., Cerritos, California on August 31, 1986; San Diego, California on September 25, 1978). A little known fact is that most airplane crashes at or in the vicinity of an airport are survivable. Many plane occupants survive the force of the ground impact only to die minutes later in the subsequent smoke and fire conditions. These consequences can be significantly reduced by a prepared and comprehensive response of local emergency services. During the evaluation, the author found two possible areas of increased vulnerability within the City of Newport Beach. These are discussed in detail below. Balboa Island: In a worst -case scenario, a fully loaded commercial plane might crash into Marine Avenue on a sunny Saturday afternoon. The area is usually crowded with cars, pedestrians, and day visitors, and the island's access and egress is limited to a small bridge. Many of the two-story buildings, including shops, small restaurants, and . residences, are wood -frame structures, and very close to one another. A fire fed by thousands of gallons of jet fuel could quickly spread through the neighborhood and consume most of the buildings. Countless casualties on the ground would be caused by falling aircraft wreckage and the resulting fire(s). The only fire station located on Balboa Island, No. 4, might be impacted by the incident, or its response hampered by traffic congestion, people fleeing the area, debris, and narrow streets. The same problem of limited access may hinder reinforcements by other fire and rescue services. Although this scenario might be a very unlikely one, its impact would be catastrophic in terms of loss of life, destruction of property and community. It would certainly deal a tremendous blow to the local economy and tourism industry. In this scenario, the immediate response of ARFF vehicles carrying large quantities of foam can be considered essential for saving lives and property. Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-12 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Figure 7-3: Image of Balboa Island (in the Foreground) Lucking North Towards John Wayne Airport; Marine Avenue, Newport Bay and Runway 19R in a Straight Line • Upper Newport Bay: A more likely scenario than an accident on Balboa Island is a major airliner ending up in the Upper Newport Bay area. The soft underground and the abundant water might limit the impact force and the spread of fire and, therefore, ensure a high degree of survivability for the aircraft occupants. The fast and well - coordinated response of City and County emergency services into the difficult terrain is crucial. The Upper Newport Bay scenario, however, creates a significant ecological and economic hazard to the environment. The recreational value of the City of Newport Beach with its more than 9,000 registered boats would be dramatically affected. Local businesses are heavily dependant upon a clean and enjoyable bay, harbor, and oceanfront. Planes taking off from JWA (mainly short- to medium -range airliners with up to 200 passengers) can carry up to 12,000 gallons of Jet A fuel. Spilled into the marshland, the kerosene would flow through the bay and significantly pollute the waterways. According to recent newspaper articles, beaches have been closed, and swimming and diving prohibited for days due to spills of less than 400 gallons of sewage. The environmental and economic impact of an accident -related spill of thousands of gallons of Jet A fuel would therefore be devastating. • Gunnar). Kuepper ® Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-13 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Figure 7-4: Image from Upper Newport Bay Looking Towards the Ocean Other Scenarios: A) A crash into a residential area west or east of the Newport Bay has an extremely low probability because, without a doubt, the pilot crew of an airplane in distress will make • every effort to avoid these areas and attempt to stay above the uninhabited bay. Moreover, the area's population density is relatively low (mostly single freestanding houses), with the exception of some retail areas and schools. It would be a localized and manageable incident. (Such an accident would be comparable to the crash of American Airlines Flight 587 immediately after takeoff from New York's JFK Airport on November 12, 2001. All 260 people aboard perished, 12 residences were destroyed by the impact and fire, and five persons on the ground perished.) • B) A crash into a high-rise building in Fashion Island also has an extremely low probability because pilots would avoid these areas at all costs. In addition, the buildings themselves (concrete with sprinkler systems) might offer some protection for occupants. The area contains large open spaces that allow for fast egress and access for emergency vehicles. Gunnar J. Kuepper 0 Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-14 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Figure 7-5: Image of Fashion Island (to the right) With Ample Space Between Buildings and in the Area 1 Y F C) A crash into the Pacific Coast Highway bridge over the Lower Newport Bay is highly unlikely, but this is the primary connection between the northern and southern parts of Newport Beach. For an airplane to hit the overpass it would have to make a sharp turn towards the bridge. The resulting disruption would have a significant impact on tourism • and business in the area. A detour via Highway 55, Freeway 73, and Jamboree Road would cause a major inconvenience with consequences for commuters, local restaurants, retail stores, and other businesses. D) A crash into a school during classes could become a nightmare for the community of Newport Beach- As shown on Plate 7-4, numerous elementary, intermediate, and high schools are located within the City of Newport Beach. An airplane crashing into one of these facilities is extremely unlikely, but this scenario cannot be excluded. Many of these schools house hundreds of students (i.e., Newport Harbor High School at 600 Irvine Avenue, nearly 2,000; Ensign Intermediate School at 2000 Cliff Drive, more than 1,100; four elementary schools with more than 500 pupils each are located at 300 East 15" Street, at 14'h Street and Balboa Boulevard, at 2100 Mariners Drive, and 1900 Port Seabourne Way). Even if the statistical risk of such an event is extremely low, the emotional consequences of several children injured or worse will be colossal. Such an occurrence cannot be ruled out. On May 4", 2002, a BAC one -eleven aircraft crashed shortly after take off from Kano International Airport in Nigeria. The plane veered off into houses, two mosques and a school in a densely populated neighborhood approximately 1.2 miles from the runway threshold. Seventy-five people on the ground and 74 of the 77 people aboard the short-range passenger jet perished. • Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-15 i•I • ro ^. Z e e`♦ NOTES This map is intended for general land use planning only Information on this map is nol sufficient to serve as a subatitule for detailed geologic investigations of individual sites, nor does it satisfy the evaluatlon requirements set forth In geologic hazard regulations. Earth Consultants International (ECD makes no, representations or vvarranties regarding the accuracy of the data from which these maps were derived. ECI shall not be liable under any circumstances for any direct, indirect, special, incidental, or consequential damages vdth respect to any claim by any user or third parry on account of, or arising from, the use of this map. Schools and Fire Stations in Newport Beach, California EXPLANATION all, School R+ Fire Station �'•e Newport Beach City Boundary Sphere of Influence Scale: 1:60,000 0.5 0 0.5 1 1.5 Miles 1 0 -- 1 2 3 Kilometers Base Map: USGS Topographic Map from Sure!MAPS RASTER Source: City of Newport Beach 4 m Earth �— Consultants International Project Number: 2112 Date: July, 2003 Plate 7-4 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Mitigation procedures that might save lives in an airplane crash scenario are similar to those addressing other hazards. It includes clear and designated evacuation routes and procedures, well maintained fire suppression systems, regular drills and testing, and a proactive mindset of teachers, parents, and children. An up-to-date and exercised school emergency plan will reduce the number of potential casualties. E) Mid -air collisions (i.e., Cerritos, California on August 31, 1986; San Diego, California on September 25, 1978), mid -air bombings (i.e., PanAm Flight 103 above Lockerbie, Scotland on December 21, 1988), and mid -air break-ups (i.e., Alaska Airlines MD 80 off the Coast of Ventura County on January 31, 2000; American Airlines on November 12, 2001 in New York City) are, despite their seemingly increased frequency in southern California, extremely rare events. Crashes with significant loss of life on the ground are the exception and rarely produce more than ten fatalities in a community (see statistics of ground fatalities in the appendix of this report). The FAA has classified the airspace surrounding JWA, which includes the City of Newport Beach, as CHARLIE. Every aircraft, including helicopters and general aviation planes must announce its flight intention and receive permission from JWA Air Traffic Control to enter this space up to a height of 5,000 feet. Cargo Planes: On October 4, 1992, an El Al Cargo Boeing 747 crashed shortly after take -off from Amsterdam's Schiphol airport into a 12-story high-rise apartment building • in a suburb of Amsterdam. The flight crew of four died, as did 43 people on the ground, where many others sustained injuries. Despite the magnitude of the accident, it is not considered a catastrophe, as it was a manageable incident, handled by local resources and authorities. The plane carried a load of more than 120 tons. In the aftermath, more than 850 people, including residents, emergency and recovery workers, and police officers experienced long-term health effects, ranging from respiratory problems to neurological ailments. A report published in 1998, six years after the fiery accident, revealed the contents of the freight. It included six tons of military cargo and 10 tons of chemicals, including DMMP (dimethylmethyphosphonate), a substance used for the production of the nerve gas Sarin. It is absolutely crucial that every plane crash is handled with the same consideration as a major hazmat release. This includes proper protection, equipment, and training for emergency responders, and procedures for the evacuation of residents from the nearby and downwind areas. Establishing these precautions is also important in the event that a plane crashes on the airport or in neighboring areas (i.e., the city of Costa Mesa) and exposes residents of Newport Beach to harm. JWA is allowed to operate up to 85 passenger flights and four cargo flights daily. The probability that one of these planes should crash into Newport Beach is close to random. More or less equally distributed throughout passenger and cargo carriers are • accident -causing factors such as aging aircraft, faulty maintenance, and human error. Only a few air carriers have spotless safety records (i.e., Southwest airlines never had a Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-17 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • fatal accident). Most major cargo carriers have had plane crashes (i.e., Emery Worldwide February 1991 DC-9 crash in Cleveland, Ohio and February 2000 CD-8 crash in Sacramento, California; Federal Express MD-11 crash of July 1997 in Newark, New Jersey, the Freeport, Philippines crash of another MD-11 in October 1999, and a Boeing 727 crash on July 26, 2002 in Tallahassee, Florida). The likelihood of one plane crashing on any given day is equally disseminated throughout all flights. The probability may be compared with the game of roulette. It does not matter whether one or twenty odd numbers are played in a row, the next number to come has an equal chance of being odd, even, or zero. Coincidence also applies to the small number of plane crashes. Considering the environment at JWA, the models of airplanes flown there, and the statistically low probability of plane crashes in Newport Beach (1 in 41 years), the risk of a cargo plane accident is on par with a passenger plane crash. Even three cargo plane crashes in a row in Newport Beach would be within the principle of acceptable coincidence. 7.6 Response Agencies and Procedures 7.6.1 Newport Beach Fire Department (NBFD) Newport Beach maintains its own fire service with approximately 120 uniformed members operating out of eight stations. • During the year 2001, the department responded to more than 7,600 calls, including 360 fires, 5,250 medical situations, 1,200 other emergencies, and 850 service type demands. Fire Station No. 7 is located at 2301 Zenith in the northern part of the City, close to JWA (see Plate 7-4). The three -person engine company is frequently called for mutual aid to the airport, particularly for medical emergencies. Newport Beach Fire Department has incorporated the Life Guard Services, which covers the coastal beaches. Lifeguards are available from 7 A.M. to 6 P.M. (during the summer, as late as 9.30 p.m.), and operate three boats. Also, the Lifeguard Services has a dive team with 16 trained members. During the night, two lifeguards are on call and required to be at their station within 30 minutes. Mass Casualty Incident Experience: On Monday, September 2, 2002, a multi -casualty event occurred at 500 South Bay Front in Newport Beach. The motor vehicle/pedestrian accident involved more than ten patients. Fortunately, most of them sustained only minor injuries. A thorough look into the response activities revealed some opportunities for improvement: a) The accident occurred at a very difficult location. As described in the Balboa Island scenario above, traffic congestion can become a major factor. Newport Beach Emergency Services arrived in a very reasonable time. However, the magnitude of the accident activated different agencies, and multiple fire, EMS, • police, and rescue vehicles responded to the location on the narrow street. The vehicles had limited space to maneuver and sometimes blocked each other. Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-18 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • b) EMS resources from outside the City were requested due to the number of victims. Those ambulances from neighboring communities are not always familiar with the City and its layout and, in this case, had difficulties locating and arriving at the site in time. Because this is a common challenge in non -rectangular environments, rendezvous points and escort procedures should be established to ensure smooth operations in critical times. Smaller fire departments, particularly in affluent jurisdictions, are fortunate in not having to experience great numbers of mass -casualty events. But with the rarity of these events comes the lack of experience in practicing proper procedures and operations. Training must focus on these rare events, rather than on incidents that are handled on a daily or weekly basis. 7.6.2 Orange County Fire Authority (OCFA) OCFA serves 1.3 million people living in 460,000 housing units in 19 cities and the unincorporated parts of Orange County. The agency responded in 2001 to more than 73,000 calls within its jurisdiction covering of an area of 550 square miles served by 60 fire stations. OCFA Station No. 33 provides airport and aircraft fire protection for JWA. • 7.6.3 Newport Beach Police Department (NBPD) Helicopter Division One of the most impressive assets for a city the size of Newport Beach is the existence of a helicopter division staffed 7 A.M. to 3 A.m., 7 days a week. Helicopters have proven their worth in countless plane crashes because of their ability to aid in the: ➢ location of the incident site, ➢ search for and location of survivors, ➢ rescue and evacuation of survivors from areas not easily accessible to ground crews (i.e., Air Florida Boeing 737 crash into the Potomac River in Washington, DC, on January 13, 1982), ➢ assessment of the overall damage and situation, and ➢ direct response operations of ground crews. 7.6.4 Orange County Sheriff Harbor Patrol — Waterways Within the jurisdiction of Orange County and protected by the Harbor Patrol Division of the Orange County Sheriff Department (OCSD) are Upper and Lower Newport Bay and the harbor areas. An OCSD captain oversees the daily operations of the agency, which provides law enforcement, marine fire -fighting, open -water rescue, and vessel assistance for the three Orange County harbors of Sunset/Huntington Harbor, Newport Harbor, and Dana Point, as well as an additional 42 miles of Orange County coastline. • Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-19 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Deputies assigned to the Harbor Patrol Division are also trained in environmental law and are qualified and equipped as "first -responders' to hazardous material spills. They are fully trained peace officers and receive nearly 800 hours of additional training in navigation, marine fire -fighting, heavy weather rescue boat operations, boat handling, and advanced first aid, including the administering of oxygen and the use of automated external defibrillators. • 7-6: Image of a Eurocopter used by the Newport Beach Police Department The Newport Beach Harbor Patrol office at 1901 Bayside Drive serves as the headquarters for the entire division. The building contains a 800 MHz dispatch area and an emergency operations center. Included in the Harbor Patrol Division is the Sheriff's Dive Team. It consists of 11 divers who are trained in underwater search, rescue, and recovery operations along with swift water rescues. The Harbor Patrol rescue fleet consists of six twin -engine fireboats and eight single -engine patrol boats. The fleet provides its services 24 hours a day, 7 days a week, providing services to Newport Harbor, Dana Point Harbor and Huntington Harbor. This agency is a tremendous resource for Newport Beach emergency services in the case of an airplane crash into the bay, the harbor areas, or the ocean (which is the most likely scenario). • Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-20 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 7.6.5 Safety of Newport Beach Emergency Crews Responding to JWA Due to their close proximity, emergency crews from Newport Beach may be called to JWA to assist Orange County Emergency Services in major events, ranging from plane crashes, to terminal or hanger fires, to acts of terrorism. The aviation industry has been subjected to acts of terrorism and violence since its early beginnings. These attacks have not stopped in the aftermath of September 11, 2001. Terminals have been bombed and shooting attacks (i.e., New Orleans Airport on May 23, 2002, LAX on July 4, 2002) are still common occurrences. JWA may be even more exposed now, because LAX is improving security and is becoming a "hard" target. Potential attackers might look at nearby JWA and consider its facilities a "softer" target for an attack. To reduce the risk of life and health for fire, EMS, and police personnel, the City of Newport Beach should consider providing the following: ➢ terrorism awareness training (including the threat of secondary devices, nuclear, biological, and chemical agents; operating procedures for situations involving active shooters; etc.); and ➢ airplane/airport related hazard familiarization for those emergency crews that might respond to an incident on airport premises. The loss • of any emergency service individual in the line of duty has a tremendous emotional impact on the community at large and can cause major grievances. Tragedies can be avoided through preparedness and protective measures. 7.6.6 Communication One of the most critical factors for the effectiveness of life saving operations and the prevention of further escalation and damage in an airplane crash is communication. Direct communication between Traffic Control at JWA and Fire/Rescue Dispatch for the City of Newport Beach, which is located in the City of Anaheim, does not exist. Direct radio communication exists between John Wayne ATC (Air Traffic Control) and the NBPD helicopter crew. Direct radio communication exists between the NBPD helicopter and NBPD and NBFD ground crews. Direct radio communication is exercised between NBFD units and OCFA units. Direct radio communication exists between the different emergency services working on the water (US Coast Guard, NBFD Lifeguards, Sheriff's Harbor Patrol). Although an area for communications improvement exists between water -based and land - based agencies, the commanding officers involved understand each other's jurisdictions and responsibilities and try not to interfere in the operations of other agencies. Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-21 • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Another flaw in communications and coordination seems to exist between the local agencies and the US Coast Guard (USCG). USCG has jurisdiction and the appropriate equipment to perform ocean search and rescue operations. However, their response capabilities, times, and procedures for an airplane crash off the shores of Newport Beach are largely unknown. 7.6.7 Training and Coordination A formalized training program between the different entities (NBFD, NBPD, OCFA, OC Sheriff) does not exist. However, NBFD units participated in the tri-annual full-scale exercises at JWA in September of 1998 and May of 2002, and NBFD Fire Station No. 7 regularly responds to the airport. A mutual aid agreement between NBFD and OCFA exists and is exercised on a regular basis. Figure 7-6: JWA Full -Scale Disaster Exercise with Participation of NBFD Units 3V u1Nrl�e • �! c, . ro .. y r - 7.7 Aftermath of an Airplane Crash It is important to realize that an airplane crash into a city the size of Newport Beach or off its shores will stretch all public services to the limit. (See experiences of Ventura County in the aftermath of the deadly crash of an Alaska Airlines MD-83 on January 31, 2000. While en route from Puerto Vallarta to San Francisco, the aircraft crashed into the Pacific Ocean south of Point Mugu in 650 feet of water, approximately 10 miles off the shore. Radio transmissions from the plane indicated the pilots were struggling with a jammed stabilizer for the last 11 minutes of the flight before diving into the sea. They tried to make an emergency landing at Los Angeles International Airport, but control was lost and the MD-83 was seen in a nose -down attitude, • Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-22 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • spinning and tumbling in a continuous roll, inverted before it impacted the sea. All 88 people on board perished.) The services needed in the aftermath of an airliner crash range from space and accommodations for hundreds of media representatives, airline employees, care providers, and family members (consider at least three family members for every airplane occupant), to site security, evidence preservation, transportation arrangements for those involved, body recovery, and even memorial services. All services will be required in a time of great pressure and emotional tensions. Therefore, it is crucial that the different roles and responsibilities of the County, the Airport, and the City of Newport Beach (who takes care for what, who reports to whom) are determined in advance, and that clear documentation (i.e., Memorandum of Understanding) exists. The way in which an incident is handled can make or break a crisis. The lack of proper crisis management or even the perception of failure can have a tremendous negative impact on the prestige of the city impacted by the tragedy (referred to as the CNN factor). A plane crash always attracts the national and often the international media. Timely and coordinated public information management is essential. In addition to the air carrier involved in an accident, in Newport Beach the other agencies involved will be JWA, Orange County, FAA, NTSB, etc. It is recommended that the responsibilities and actions to be taken are determined in advance and understood by all Authorities Having Jurisdiction (AHJ). The objective is to avoid • conflicting statements and speculation, and to establish a single point of contact for the media (Joint Media Center). It must be stressed that failure to address the media and the perception of the public in a high profile accident such as a plane crash, may damage the reputation of the City's leadership or of the City as a whole. 7.7.1 Financial Impacts The aftermath of a major airplane accident will require numerous resources, facilities, personnel, equipment, logistics, etc., and will become a costly endeavor. Most of these activities (particularly response, salvage operations, and scene security) will be covered by the airline and/or its insurance carrier. However, based on experience, the NTSB and other federal agencies (i.e., FAA, FBI) may demand space, manpower, equipment, accommodations, etc., to support their investigative efforts, which can last for months. It is strongly recommended, therefore, to address reimbursement and payment issues before committing City resources to an expensive operation. It is helpful to have procedures in place to track and document all activities, expenses, manpower, overtime, supplies, claims (i.e., injured personnel), and other costs for reimbursement. 7.8 Summary and Recommendations • The City of Newport Beach is located in the take -off path of aircraft departing John Wayne Airport QWA), which statistically increases the risk of a plane crash into the City. A commercial plane Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-23 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • accident might be a 1-in-25- to 1-in-40-year occurrence. However, pilots are instructed to follow the Newport Bay away from residential or developed areas. The author did not detect a hazard risk that might be likely to result in a catastrophe for Newport Beach. Given the amount of resources available in the City and throughout the County of Orange, any impact will be significantly reduced by fast, coordinated, and skilled response operations of all available emergency services. Nevertheless, it is highly recommended that arrangements be made to ensure that ARFF units can and will respond immediately to a major airplane accident within the City limits of Newport Beach. Any JWA ARFF vehicle responding to an off -airport aircraft accident is equipped to and required to use the designated 800 MHz frequency for communicating with the Fire Incident Commander of the Authority Having Jurisdiction (AHJ). It is critically important and required by FAA regulations that the airport is not allowed to operate if the minimum fire protection coverage is not guaranteed. Therefore, airport fire vehicles are allowed to respond off -site only if the airport has been shut down to commercial air traffic. According to JWA documents, the primary fire, rescue, and law enforcement responsibility for off - airport accidents is with the jurisdiction(s) involved. It is recommended that a formalized Memorandum of Understanding regarding the response of ARFF vehicles in case of commercial airliner crash within the City of Newport Beach be established between John Wayne Airport, the Orange County Fire Authority, and the City of Newport Beach. • Specific recommendations that can be made to further reduce the impact of aviation hazards in the City of Newport Beach include the following: Designate staging areas and rendezvous points for mutual aid agencies and procedures to escort outside ambulances, fire companies, etc., to the incident site, and casualty collection points. Provide a formalized Aircraft Rescue Fire Fighting (ARFF) training program (including airport and aircraft familiarization, fuel fire extinguishment, hazards associated with airplanes and aircraft cargo, safety procedures, aviation communications, evacuation, and rescue operations) for all firefighters and Chief Fire Officers in Newport Beach. Provide ARFF awareness training for all Newport Beach emergency personnel on a regular basis. Provide every emergency response unit (vehicles and individuals) with a laminated Airplane Crash Checklist (ACC), as described in the appendix Develop, implement, and exercise a City-wide aviation emergency response plan. Conduct comprehensive tabletop and full-scale exercises on mass -casualty events in areas potentially at risk (Upper and Lower Newport Bay, Balboa Island, Main Channel, Pacific Ocean), with the participation of all available agencies, jurisdictions, and resources. Develop clear mutual -aid agreements and Memoranda of Understanding with the airport fire service, county emergency and law enforcement agencies, USCG, private ferry • providers, and other potential resources. Gunnar J. Kuepper Q Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-24 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA . As part of a mitigation effort to prevent or reduce the risk of aviation disaster, the City of Newport Beach might choose to steer JWA towards limiting landing and departure rights to commercial airplanes not exceeding a specific age. Consider providing terrorism awareness training to emergency crews that might respond to an incident on JWA premises. Address reimbursement and payment issues before committing City resources to an expensive operation. • Gunnar J. Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-25 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 7.9 Sources • The findings in this report are based on the following: On -site ground visits to the City of Newport Beach and John Wayne Airport Aerial tour of the Newport Beach and John Wayne Airport area Publications, Media, and Internet Resources In -person interviews with: o Donna Boston, Emergency Services Coordinator, City of Newport Beach o Joe Davis, Captain, Airport Police Services Division, Orange County Sheriff Department o Michael R. Hart, Deputy Director Operations, John Wayne Airport o Paul Henisey, Captain, Police Department, City of Newport Beach o Marty Kasules, Captain, Harbor Patrol, Orange County Sheriff Department. o Timothy Riley, Fire Chief, City of Newport Beach o Chuck Ullmann, Air Traffic Manager, FAA Tower, John Wayne Airport o David R. Wilson, Chief Battalion 5, Orange County Fire Authority The author (Gunnar K. Kuepper) wishes to express his gratitude to each agency and individual who committed time and energy to assist in this effort. He is particularly grateful to Captain Paul Henisey of the Newport Beach PD for his generous support. Gunnar J. Kuepper ® Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-26 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • APPENDIX 1) AIRPLANE CRASH CHECKLIST (ACC) At least 7 in 10 plane crashes occur on or near an airport; these accidents are often survivable. To ensure proper response operations: ➢ All emergency units (Police, Fire, EMS, etc.), in a 15-mile radius of a commercial airport should have an airplane crash checklist (ACC) ➢ Checklists should be laminated and put into every glove compartment ➢ Checklists must follow the KISS principle (Keep It Simple, Stupid) and should include: o Grid -map of the airport o Staging areas and access gates o Specifically assigned radio frequencies o Priorities and DOs & DON'Ts on airports / at aircraft crash sites: • Always approach from upwind • Always use PPE (personnel protective equipment) • No freelancing: report and work exclusively within ICS (Incident Command • System • Stay alert for the following hazards: Fuel can always ignite Sharp metal debris Force of a working engine Unknown freight hazmats Bio-hazmat Damaged aircraft structures can collapse and/or roll over 2) LAWS and REGULATIONS Code of Federal Regulations (CFR), Federal Aviation Regulations (FAR) Title 14, Part 139 — Certification and Operations: Land Airports Serving Certain Air Carriers Subpart D — Operations 139.315 Aircraft rescue and firefighting: Index determination 139.317 Aircraft rescue and firefighting: Equipment and agents 139.319 Aircraft rescue and firefighting: Operational requirements 139.325 Airport emergency plan NTSB Part 830 — Notification and reporting of aircraft accidents or incidents and overdue aircraft, and preservation of aircraft wreckage, mail cargo, and records 0 CFR, Title 49, Chapter XII, Port 1500, Transportation Security Administration Gunnar ). Kuepper B Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-27 • HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Aviation Disaster Family Assistance Act of 1996 3) GUIDELINES FAA Advisory Circulars, AC 150/5210-17 and NFPA Guidelines and Standards, NFPA 415 AC 150/5200— 12 B - Fire Department Responsibility in Protecting Evidence at the Scene of an Aircraft Accident AC 150/5200 — 31 A - Airport Emergency Plans AC 150/5210 — 6C - Aircraft and Fire Rescue Facilities and Extinguishing Agents AC 150/5210 — 7C - Aircraft Rescue and Firefighting Communications AC 150/5210 —13A - Water Rescue Plans, Facilities and Equipment AC 150/5210 — 14A - Airport Fire and Rescue Personnel Protective Clothing AC 150/5210 —15 - Airport Rescue and Firefighting Station Building Design AC 150/5210 — 17- Programs for Training of Aircraft Rescue and Firefighting Personnel AC 150/5210 —18 - Systems for Interactive Training of Airport Personnel AC 150/5210 — 19 - Drivers Enhanced Vision System AC 150/5220 — 4B - Water Supply Systems for ARFF Protection AC 150/5220 —10B - Guide Specification for Water/Foam ARFF Vehicles AC 150/5220 —17A - Design Standards for an ARFF Training Facility AC 150/5220 —19 - Guide Specification for Small Dual Agent ARFF Vehicles NFPA (National Fire Protection Association) Guidelines and Standards NFPA 402 Aircraft Rescue and Fire Fighting Operations NFPA 403 Aircraft Rescue and Fire -Fighting Services at Airports NFPA 407 Aircraft Fuel Servicing NFPA 409 Aircraft Hangars NFPA 414 Aircraft Rescue and Fire -Fighting Vehicles NFPA 415 Airport Terminal Buildings, Fueling Ramp Drainage And Loading Walkways NFPA 418 Heliports NFPA 422 Aircraft Accident Response NFPA 1003 Airport Fire Fighter Professional Qualifications NFPA 1600 Emergency/Disaster Management and Business Gunnar J. Kuepper 0 Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-28 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Continuity Programs 4) WEBSITES Boeing Company <www.boeing.com> Emergency & Disaster Management, Inc. <www.edmus.info> Federal Aviation Administration <www.faa.gov> International Civil Aviation Organization <www.icao.org> John Wayne Airport <www.ocair.com> National Transportation Safety Board <www.ntsb.gov> City of Newport Beach <www.city.newport-beach.ca.us> Newport Beach Firefighters Association <www.nbfa.org> Newport Beach Police Department <www.nbpd.org> County of Orange <www.oc.ca.gov> Orange County Fire Authority <www.ocfa.org> Orange County Sheriff Department <www.ocsd.org> Transportation Security Administration <www.tsa.gov> Air Disasters <www.airdisaster.com> • 5) STATISTICS Ground Fatalities Worldwide Aircraft Accidents with Ground Fatalities in 2002, 2001, 2000, 1999 and 1998 caused by: o Military aircraft accidents • 5 on October 1, 2002, when two Indian navy aircraft flying in formation in a military flyby collided in mid -air and crashed. One plane crashed into a house under construction, while the other crashed onto a field next to a highway in Vasco, India. • 85 on July 27, 2002, when a Russian combat fighter Su-76 performing aerobatics crashed into crowd of spectators at an air show at Skniliv Airport in the Ukraine. • 3 on March 7, 1999, when an Indian Air Force Antonov An-32 crashed into a building site while attempting to land at New Delhi Airport, India. • t on March 28, 1998, when a Peruvian Air Force Antonov An-32 carrying villagers stranded by flooding crashed near a shantytown 1.5 miles from the runway while attempting to land at Piura Airport, Peru. • 20 on February, 1998, when a US Marine Corps Grummand EA-66 fighter jet struck and severed the cable to a gondola causing it to fall 300 feet to the ground, resulting in the deaths of 20 people on board near Cavalese in Trento, • Italy. Gunnar J. Kuepper © Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-29 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA o Commercial plane accidents • 75 on May 4, 2002, when an EAS Airline BAC one -eleven crashed shortly after take off into houses, two mosques, and a school in the densely populated neighborhood of Gwammaja, approximately 1.2 miles from Kano International Airport, Nigeria. • 5 on November 12, 2001, when an American Airlines Airbus A 300 crashed into a residential neighborhood three minutes after taking off from JFK Airport in New York City. • 4 on October 8, 2001, when a SAS MD-87 collided at Linate Airport with a German Cessna Citation II business jet. The MD-87 then swerved off the runway and crashed into a baggage handling building. • 1 on March 24, 2001, when an Air Caraibes de Havilland Canada DHC-6 Twin Otter crashed into a house on a landing attempt at St. Barthelemy in the French West Indies. • 4 on October 6, 2000, when an Aeromexico DC-9 overshot the runway near Reynosa, Mexico, while landing and crashed into vehicles and houses, finally coming to rest in a canal. • 4 on July 2000, when an Air France Concorde crashed into a small hotel complex after taking off from Charles de Gaulle Airport near Paris, France. • 5 on July 17, 2000, when a Indian Airlines Boeing 737 attempted to land at Patna Airport and crashed into houses in the Gardanibagh district in India. • 7 on June 22, 2000, when a Wuhan Airlines Xian Yunshuji Y-7-100C plane crashed into the Hanjiang River while attempting to land at Wuhan's Wanjiatun • Airport in thunderstorms and heavy rain. Seven people aboard a boat on the southern bank of the river were killed when they were swept away by the impact of the crash. • 4 on March 24, 2000, when a Sky Cabs Cargo Antonov An-12 ran out of fuel while landing and crashed short of the runway into houses in Kadirana, Sri Lanka. • 1 on January 5, 2000, when a Skypower Express Airways Embraer 110 crashed into a field adjacent to the runway while attempting to land in Abuja, Nigeria. • 9 on December 1, 1999, when a Cubana de Aviacidn DC-10 overshot the runway and crashed into houses in the La Libertad section while attempting to land at La Aurora International Airport, Guatemala City, Guatemala. • 10 on August 31, 1999, when a LAPA Airlines Boeing 737 attempting to take off from Jorge Newberry Airport in Buenos Aires, Argentina, overran the runway, skidded across a service road, and crashed into several cars and onto a golf course. • 19 on February 2, 1999, when a Savannair Antonov An-12 crashed into the Cazenga district destroying five houses while attempting to land at Luanda Airport, Angola. • 4 on October 21, 1998, when an Ararat Avia Airlines Yakovlev YAK-40 airplane struck a military bus as it crossed the runway while attempting to take off from Yerevan Airport, Armenia. • 10 on August 29, 1998, when a Cubana de Aviation Tupolev Tu-154 aircraft • crashed into an auto body shop and came to rest in a soccer field during takeoff from Quito, Ecuador. Gunnar). Kuepper @ Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-30 t� HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • 2 on July 30, 1998, when an Indian Airlines crashed shortly after taking from Kochi Airport, India. • 3 on March 22, 1998, when a Philippine Airlines Airbus A-320 overran the runway, went through a concrete perimeter fence, crossed a small river and hit a karaoke house before stopping near a market during a landing attempt at Bacolod Airport in the Philippines. • 7 on February 16, 1998, when a China Airlines Airbus A-300 crashed into a residential neighborhood while attempting to land at the international Airport of Taipei, Taiwan. Gunnar J. Kuepper Q Emergency & Disaster Management for Earth Consultants International 2003 Aviation Hazards Page 7-31 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Appendix A GLOSSARY Acceleration — The rate of change for a body's magnitude, direction, or both over a given period of time. Active fault - For implementation of Alquist-Priolo Earthquake Fault Zoning Act (APEFZA) requirements, an active fault is one that shows evidence of, or is suspected of having experienced surface displacement within the last 11,000 years. APEFZA classification is designed for land use management of surface rupture hazards. A more general definition (National Academy of Science, 1988), states "a fault that on the basis of historical, seismological, or geological evidence has the finite probability of producing an earthquake" (see potentially active fault). Adjacent grade — Elevation of the natural or graded ground surface, or structural fill, abutting the walls of a building. See highest adjacent grade and lowest adjacent grade. Aftershocks - Minor earthquakes following a greater one and originating at or near the same place. Aggradation —The building up of earth's surface by deposition of sediment. Alluvium - Surficial sediments of poorly consolidated gravels, sand, silts, and clays deposited by flowing water. Anchor — To secure a structure to its footings or foundation wall in such a way that a continuous load transfer path is created and so that it will not be displaced by flood, wind, or seismic forces. • Aplite — A light-colored igneous rock with a fine-grained texture and free from dark minerals. Aplite forms at great depths beneath the earth's crust. Appurtenant structure — Under the National Flood Insurance Program, a structure which is on the same parcel of property as the principal structure to be insured and the use of which is incidental Argillic— Alteration in which certain minerals of a rock or sediments are converted to clay. Armor — To protect slopes from erosion and scour by flood waters. Techniques of armoring include the use of riprap, gabions, or concrete. Artesian — An adjective referring to ground water confined under hydrostatic pressure. The water level in wells drilled into an artesian aquifer (also called a confined aquifer) will stand at some height above the top of the aquifer. If the water reaches the ground surface the well is a "flowing" artesian well. Attenuation — The reduction in amplitude of a wave with time or distance traveled. A zone — Under the National Flood Insurance Program, area subject to inundation by the 100-year flood where wave action does not occur or where waves are less than 3 feet high, designated Zone A, AE, A1- A30, A0, AH, or AR on a Flood Insurance Rate Map (FIRM). Base flood — Flood that has as 1-percent probability of being equaled or exceeded in any given year. Also known as the 100-year flood. • Base Flood Elevation (BFE) — Elevation of the base flood in relation to a specified datum, such as the National Geodetic Vertical Datum or the North American Vertical Datum. The Base Flood Elevation is the Earth Consultants International Glossary Page A-1 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA basis of the insurance and floodplain management requirements of the National Flood Insurance Program. Basement — Under the National Flood Insurance Program, any area of a building having its floor subgrade on all sides. (Note: What is typically referred to as a "walkout basement," which has a floor that is at or above grade on at least one side, is not considered a basement under the National Flood Insurance Program.) Beach nourishment— Replacement of beach sand removed by ocean waters. Bedding - The arrangement of a sedimentary rock in beds or layers of varying thickness and character. Bedrock - Designates hard rock that is in its natural intact position and underlies soil or other unconsolidated surficial material. Bench - A grading term that refers to a relatively level step excavated into earth material on which fill is to be placed. Berm — Horizontal portion of the backshore beach formed by sediments deposited by waves. Biotite — A general term to designate all ferromagnesian micas. Blind thrust fault - A thrust fault is a low -angle reverse fault (top block pushed over bottom block). A "blind" thrust fault refers to one that does not reach the surface. Breakaway wall — Under the National Flood Insurance Program, a wall that is not part of the structural support of the building and is intended through its design and construction to collapse under specific lateral loading forces, without causing damage to the elevated portion of the building or supporting foundation system. Breakaway walls are required by the National Flood Insurance Program regulations for any enclosures constructed below the Base Flood Elevation beneath elevated buildings in Coastal High Hazard Areas (also referred to as V zones). In addition, breakaway walls are recommended in areas where flood waters flow at high velocities or contain ice or other debris. Building code — Regulations adopted by local governments that establish standards for construction, modification, and repair of buildings and other structures. Built-up roof covering — Two or more layers of felt cemented together and surfaced with a cap sheet, mineral aggregate, smooth coating, or similar surfacing material. Bulkhead —Wall or other structure, often of wood, steel, stone, or concrete, designed to retain or prevent sliding or erosion of the land. Occasionally, bulkheads are use to protect against wave action. Cast -in -place concrete — Concrete that is poured and formed at the construction site. Cladding— Exterior surface of the building envelope that is directly loaded by the wind. Clay - A rock or mineral fragment having a diameter less than 1/256 mm (4 microns, or 0.00016 in.). A clay commonly applied to any soft, adhesive, fine-grained deposit. Claystone - An indurated clay having the texture and composition of shale, but lacking its fine lamination. A massive mudstone in which clay predominates over silt. Coastal A zone — The portion of the Special Flood Hazard Area landward of a V zone or landward of an open coast without mapped V zones (e.g., shorelines of the Great Lakes), in which the principal sources of is flooding are astronomical tides, storm surge, seiches, or tsunamis, not riverine sources. The flood forces in Earth Consultants International Glossary Page A-2 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • coastal A zones are highly correlated with coastal winds or coastal seismic activity. Coastal A zones may therefore be subject to wave effects, velocity flows, erosion, scour, or combinations of these forces. See A zone and Non -coastal A zone. (Note: the National Flood Insurance Program regulations do not differentiate between coastal A zones and non -coastal A zones.) Coastal barrier — Depositional geologic feature such as a bay barrier, tombolo, barrier spit, or barrier island that consists of unconsolidated sedimentary materials; is subject to wave, tidal, and wind energies; and protects landward aquatic habitats from direct wave attack. Coastal Barrier Resources Act of 1982 (CBRA) — Act (Pub. L. 97-348) that established the Coastal Barrier Resources System (CBRS). The act prohibits the provision of new flood insurance coverage on or after October 1, 1983, for any new construction or substantial improvements of structures located on any designated undeveloped coastal barrier within the CBRS. The CBRS was expanded by the Coastal Barrier Improvement Act of 1991. The date on which an area is added to the CBRS is the date of CBRS designation for that area. Coastal flood hazard area — Area, usually along an open coast, bay, or inlet, that is subject to inundation by storm surge and, in some instances, wave action caused by storms or seismic forces. Coastal High Hazard Area — Under the National Flood Insurance Program, an area of special flood hazard extending from offshore to the inland limit of a primary frontal dune along an open coast and any other area subject to high -velocity wave action from storms or seismic sources. On a Flood Insurance Rate Map, the Coastal High Hazard Area is designated Zone V, VE, or VI-V30. These zones designate areas subject to inundation by the base flood where wave heights or wave runup depths are greater than or equal to 3.0 feet. • Code official — Officer or other designated authority charged with the administration and enforcement of the code, or a duly authorized representative, such as a building, zoning, planning, or floodplain management official. Column foundation — Foundation consisting of vertical support members with a height -to -least -lateral - dimension ratio greater than three. Columns are set in holes and backfilled with compacted material. They are usually made of concrete or masonry and often must be braced. Columns are sometimes known as posts, particularly if the column is made of wood. Concrete Masonry Unit (CMU) — Building unit or block larger than 12 inches by 4 inches by 4 inches made of cement and suitable aggregates. Conglomerate - A coarse -grained sedimentary rock composed of rounded to subangular fragments larger than 2 mm in diameter set in a fine-grained matrix of sand or silt, and commonly cemented by calcium carbonate, iron oxide, silica or hardened clay. The consolidated equivalent of gravel. Connector — Mechanical device for securing two or more pieces, parts, or members together, including anchors, wall ties, and fasteners. Consolidation - Any process whereby loosely aggregated, soft earth materials become firm and cohesive rock. Also the gradual reduction in volume and increase in density of a soil mass in response to increased load or effective compressive stress, such as the squeezing of fluids from pore spaces. Contraction joint — Groove that is formed, sawed, or tooled in a concrete structure to create a weakened - plane and regulate the location of cracking resulting from the dimensional change of different parts of the structure. See Isolation joint. Earth Consultants International Glossary Page A-3 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Corrosion -resistant metal — Any nonferrous metal or any metal having an unbroken surfacing of nonferrous metal, or steel with not less than 10 percent chromium or with not less than 0.20 percent copper. Coseismic rupture - Ground rupture occurring during an earthquake but not necessarily on the causative fault. Cretaceous — The final period of the Mesozoic era (before the Tertiary period of the Cenozoic era), thought to have occurred between 136 and 65 million years ago. Dead load — Weight of all materials of construction incorporated into the building, including but not limited to walls, floors, roofs, ceilings, stairways, built-in partitions, finishes, cladding, and other similarly incorporated architectural and structural items and fixed service equipment. See Loads. Debris — (Seismic) The scattered remains of something broken or destroyed; ruins, rubble; fragments. (Flooding, Coastal) Solid objects or masses carried by or floating on the surface of moving water. Debris impact loads —Loads imposed on a structure by the impact of floodborne debris. These loads are often sudden and large. Though difficult to predict, debris impact loads must be considered when structures are designed and constructed. See Loads. Debris flow - A saturated, rapidly moving saturated earth flow with 50 percent rock fragments coarser than 2 mm in size which can occur on natural and graded slopes. Debris line — Line left on a structure or on the ground by the deposition of debris. A debris line often indicates the height or inland extent reached by floodwaters. Deck — Exterior floor supported on at least two opposing sides by an adjacent structure and/or posts, piers, or i other independent supports. Deflected canyons - A relatively spontaneous diversion in the trend of a stream or canyon caused by any number of processes, including folding and faulting. Deformation - A general term for the process of folding, faulting, shearing, compression, or extension of rocks. Design flood — The greater of either (1) the base flood or (2) the flood associated with the flood hazard area depicted on a community's flood hazard map, or otherwise legally designated. Design Flood Elevation (DFE) — Elevation of the design flood, or the flood protection elevation required by a community, including wave effects, relative to the National Geodetic Vertical Datum, North American Vertical Datum, or other datum. Design flood protection depth — Vertical distance between the eroded ground elevation and the Design Flood Elevation. Design stillwater flood depth — Vertical distance between the eroded ground elevation and the design stillwater flood elevation. Design stillwater flood elevation — Stillwater elevation associated with the design flood, excluding wave effects, relative to the National Geodetic Vertical Datum, North American Vertical Datum, or other datum. Development — Under the National Flood insurance Program, any manmade change to improved or • unimproved real estate, including but not limited to buildings or other structures, mining, dredging, filling, Earth Consultants International Glossary Page A-4 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • grading, paving, excavation, or drilling operations or storage of equipment or materials. Differential settlement — Non -uniform settlement; the uneven lowering of different parts of an engineered structure, often resulting in damage to the structure. Sometimes included with liquefaction as ground failure phenomenon. Dike — A tabular shaped, igneous intrusion that cuts across bedding of the surrounding rock. Diorite — A group of igneous rocks that form at great depth beneath the earth's crust. These rocks are intermediate in composition between acidic and basic rocks. Dune — See Frontal dune and Primary frontal dune. Dune toe — junction of the gentle slope seaward of the dune and the dune face, which is marked by a slope of 1 on 10 or steeper. Dynamic analysis - A complex earthquake -resistant engineering design technique (UBC - used for critical facilities) capable of modeling the entire frequency spectra, or composition, of ground motion. The method is used to evaluate the stability of a site or structure by considering the motion from any source or mass, such as that dynamic motion produced by machinery or a seismic event. Earth flow - Imperceptibly slow -moving surficial material in which 80 percent or more of the fragments are smaller than 2 mm, including a range of rock and mineral fragments. Earthquake - Vibratory motion propagating within the Earth or along its surface caused by the abrupt release of strain from elastically deformed rock by displacement along a fault. Earth's crust - The outermost layer or shell of the Earth. Effective Flood Insurance Rate Map (FIRM) — See Flood Insurance Rate Map. Enclosure — That portion of an elevated building below the Design Flood Elevation (DFE) that is partially or fully surrounded by solid (including breakaway) walls. Encroachment — Any physical object placed in a floodplain that hinders the passage of water or otherwise affects the flood flows. Engineering geologist - A geologist who is certified by the State as qualified to apply geologic data, principles, and interpretation to naturally occurring earth materials so that geologic factors affecting planning, design, construction, and maintenance of civil engineering works are properly recognized and used. An engineering geologist is particularly needed to conduct investigations, often with geotechnical engineers, of sites with potential ground failure hazards. Epicenter - The point at the Earth's surface directly above where an earthquake originated. Episodic erosion — Erosion induced by a single storm event. Episodic erosion considers the vertical component of two factors: general beach profile lowering and localized conical scour around foundation supports. Episodic erosion is relevant to foundation embedment depth and potential undermining. See Erosion. • Erodible soil — Soil subject to wearing away and movement due to the effects of wind, water, or other geological processes during a flood or storm or over a period of years. Earth Consultants International Glossary Page A-5 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Erosion — Under the National Flood Insurance Program, the process of the gradual wearing away of . landmasses. In general, erosion involves the detachment and movement of soil and rock fragments, during a flood or storm or over a period of years, through the action of wind, water, or other geologic processes. Erosion analysis — Analysis of the short- and long-term erosion potential of soil or strata, including the effects of wind action, flooding or storm surge, moving water, wave action, and the interaction of water and structural components. Expansive soil - A soil that contains clay minerals that take in water and expand. If a soil contains sufficient amount of these clay minerals, the volume of the soil can change significantly with changes in moisture, with resultant structural damage to structures founded on these materials. Fault - A fracture (rupture) or a zone of fractures along which there has been displacement of adjacent earth material. Fault segment - A continuous portion of a fault zone that is likely to rupture along its entire length during an earthquake. Fault slip rate - The average long-term movement of a fault (measured in cm/year or mm/year) as determined from geologic evidence. Federal Emergency Management Agency (FEMA) — Independent agency created in 1979 to provide a single point of accountability for all Federal activities related to disaster mitigation and emergency preparedness, response and recovery. FEMA administers the National Flood Insurance Program. Federal Insurance Administration (FIA) — The component of the Federal Emergency Management Agency directly responsible for administering the flood insurance aspects of the National Flood Insurance Program. Feldspar — The most widespread of any mineral group; constitutes --60%a of the earth's crust. Feldspars occur as components of all kinds of rocks and, on decomposition, yield a large part of the clay of a soil. Fetch — Distance over which wind acts on the water surface to generate waves. Fill — Material such as soil, gravel, or crushed stone placed in an area to increase ground elevations or change soil properties. See structural fill. Five (500)-year flood — Flood that has as 0.2-percent probability of being equaled or exceeded in any given year. Flood - A rising body of water, as in a stream or lake, which overtops its natural and artificial confines and covers land not normally under water. Under the National Flood Insurance Program, either (a) a general and temporary condition or partial or complete inundation of normally dry landareas from: (1) the overflow of inland or tidal waters, (2) the unusual and rapid accumulation or runoff of surface waters from any source, or (3) mudslides 0,e., mudflows) which are proximately caused by flooding as defined in (2) and are akin to a river of liquid and flowing mud on the surfaces of normally dry land areas, as when the earth is carried by a current of water and deposited along the path of the current, or (b) the collapse or subsidence of land along the shore of a lake or other body of water as a result of erosion or undermining caused by waves or currents of water exceeding anticipated cyclical levels or suddenly caused by an unusually high water level in a natural body of water, accompanied by a severe storm, or by an unanticipated force of nature, such as flash flood or abnormal tidal surge, or by some similarly unusual and unforeseeable event which results in flooding as defined in (1), above. Earth Consultants International Glossary Page A-6 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Flood -damage -resistant material — Any construction material capable of withstanding direct and prolonged contact (i.e., at least 72 hours) with floodwaters without suffering significant damage (i.e., damage that requires more than cleanup or low-cost cosmetic repair, such as painting). Flood elevation — Height of the water surface above an established elevation datum such as the National Geodetic Vertical Datum, North American Vertical Datum, or mean sea level. Flood hazard area — The greater of the following: (1) the area of special flood hazard, as defined under the National Flood Insurance Program, or (2) the area designated as a flood hazard area on a community's legally adopted flood hazard map, or otherwise legally designated. Flood insurance — Insurance coverage provided under the National Flood Insurance Program. Flood Insurance Rate Map (FIRM) — Under the National Flood Insurance Program, an official map of a community, on which the Federal Emergency Management Agency has delineated both the special hazard areas and the risk premium zones applicable to the community. (Note: The latest FIRM issued for a community is referred to as the effective FIRM for that community.) Flood Insurance Study (FIS) — Under the National Flood Insurance Program, an examination, evaluation, and determination of flood hazards and, if appropriate, corresponding water surface elevations, or an examination, evaluation, and determination of mudslide (i.e., mudflow) and/or flood -related erosion hazards in a community or communities. (Note: The National Flood Insurance Program regulations refer to Flood Insurance Studies as "flood elevation studies.") Flood -related erosion area or flood -related erosion prone area — A land area adjoining the shore of a lake • or other body of water, which due to the composition of the shoreline or bank and high water levels or wind -driven currents, is likely to suffer flood -related erosion damage. Flooding — See Flood. Floodplain — Under the National Flood Insurance Program, any land area susceptible to being inundated by water from any source. See Flood. Floodplain management — Operation of an overall program of corrective and preventive measures for reducing flood damage, including but not limited to emergency preparedness plans, flood control works, and floodplain management regulations. Floodplain management regulations — Under the National Flood Insurance Program, zoning ordinances, subdivision regulations, building codes, health regulations, special purpose ordinances (such as floodplain ordinance, grading ordinance, and erosion control ordinance), and other applications of police power. The term describes such state or local regulations, in any combination thereof, which provide standards for the purpose of flood damage prevention and reduction. Footing — Enlarged base of a foundation wall, pier, post, or column designed to spread the load of the structure so that it does not exceed the soil bearing capacity. Footprint — Land area occupied by a structure. Freeboard — Under the National Flood Insurance Program, a factor of safety, usually expressed in feet above a flood level, for the purposes of floodplain management. freeboard tends to compensate for the many . unknown factors that could contribute to flood heights greater than the heights calculated for a selected size flood and floodway conditions, such as the hydrological effect of urbanization of the watershed. Earth Consultants International Glossary Page A-7 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Frontal dune — Ridge or mound of unconsolidated sandy soil, extending continuously alongshore landward of the sand beach and defined by relatively steep slopes abutting markedly flatter and lower regions on each side. Gabion — Rock -filled cage made of wire or metal that is placed on slopes or embankments to protect them from erosion caused by flowing or fast-moving water. Geomorphology - The science that treats the general configuration of the Earth's surface. The study of the Classification, description, nature, origin and development of landforms, and the history of geologic changes as recorded by these surface features. Geotechnical engineer - A licensed civil engineer who is also certified by the State as qualified for the investigation and engineering evaluation of earth materials and their interaction with earth retention systems, structural foundations, and other civil engineering works. Grade beam — Section of a concrete slab that is thicker than the slab and acts as a footing to provide stability, often under load -bearing or critical structural walls. Grade beams are occasionally installed to provide lateral support for vertical foundation members where they enter the ground. Grading - Any excavating or filling or combination thereof. Generally refers to the modification of the natural landscape into pads suitable as foundations for structures. Granite — Broadly applied, any completely crystalline, quartz -bearing, plutonic rock. Ground failure - Permanent ground displacement produced by fault rupture, differential settlement, liquefaction, or slope failure. Ground' rupture - Displacement of the earth's surface as a result of fault movement associated with an earthquake. High -velocity wave action — Condition in which wave heights or wave runup depths are greater than or equal to 3.0'feet. Highest adjacent grade — Elevation of the highest natural or regarded ground surface, or structural fill, that abuts the walls of a building. Holocene — An epoch of the Quaternary period spanning from the end of the Pleistocene to the present time (10,000 years). Hornblende — The most common mineral of the amphibole group. It is a primary constituent in many intermediate igneous rocks. Hurricane — Tropical cyclone, formed in the atmosphere over warm ocean areas, in which wind speeds reach 74 miles per hour or more and blow in a large spiral around a relatively calm center or "eye." Hurricane circulation is counter -clockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. Hurricane clip or strap — Structural connector, usually metal, used to tie roof, wall, floor, and foundation members together so that they can resist wind forces. Hydrocompaction - Settlement of loose, granular soils that occurs when the loose, dry structure of the sand grains held together by a clay binder or other cementing agent collapses upon the introduction of water. Earth Consultants International Glossary Page A-8 2003 0 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Hydrodynamic loads — Loads imposed on an object, such as a building, by water flowing against and around it. Among these loads are positive frontal pressure against the structure, drag effect along the sides, and negative pressure on the downstream side. Hydrostatic loads — Loads imposed on a surface, such as a wall or floor slab, by a standing mass of water. The water pressure increases with the square of the water depth. Igneous — Type of rock or mineral that formed from molten or partially molten magma. Intensity - A measure of the effects of an earthquake at a particular place. Intensity depends on the earthquake magnitude, distance from the epicenter, and on the local geology. Isolation joint — Separation between adjoining parts of a concrete structure, usually a vertical plane, at a designated location such as to interfere least with the performance of the structure, yet such as to allow relative movement in three directions and avoid formation of cracks elsewhere in the concrete and through which all or part of the bonded reinforcement is interrupted. See Contraction joint. jetting (of piles) — Use of a high-pressure stream of water to embed a pile in sandy soil. See pile foundation. Jetty — Wall built out into the water to restrain currents or protect a structure. joist — Any of the parallel structural members of a floor system that support, and are usually immediately beneath, the floor. ka — thousands of years before present. • Lacustrine flood hazard area — Area subject to inundation by flooding from lakes. Landslide - A general term covering a wide variety of mass -movement landforms and processes involving the downslope transport, under gravitational influence, of soil and rock material en masse. Lateral force - The force of the horizontal, side -to -side motion on the Earth's surface as measured on a particular mass; either a building or structure. Lateral spreading - Lateral movements in a fractured mass of rock or soil which result from liquefaction or plastic flow or subjacent materials. Left -lateral fault —A strike -slip fault across which a viewer would see the block on the opposite side of the fault move to the left. Lifeline system - Linear conduits or corridors for the delivery of services or movement of people and information (e.g., pipelines, telephones, freeways, railroads) Lifeline system - Linear conduits or corridors for the delivery of services or movement of people and information (e.g., pipelines, telephones, freeways, railroads). Lineament — Straight or gently curved, lengthy features of earth's surface, frequently expressed topographically as depressions or lines of depressions, scarps, benches, or change in vegetation. Liquefaction - Changing of soils (unconsolidated alluvium) from a solid state to weaker state unable to • support structures; where the material behaves similar to a liquid as a consequence of earthquake shaking. The transformation of cohesionless soils from a solid or liquid state as a result of increased pore pressure and reduced effective stress. Earth Consultants International Glossary Page A-9 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Littoral — Of or pertaining to the shore, especially of the sea; coastal. • Littoral drift — Movement of sand by littoral (longshore) currents in a direction parallel to the beach along the shore. Live loads — Loads produced by the use and occupancy of the building or other structure. Live loads do not include construction or environmental loads such as wind load, snow load, rain load, earthquake load, flood load, or dead load. See Loads. Load -bearing wall —Wall that supports any vertical load in addition to its own weight. See Non -load -bearing wall. Loads — Forces or other actions that result from the weight of all building materials, occupants and their possessions, environmental effects, differential movement, and restrained dimensional changes. Permanent loads are those in which variations over time are rare or of small magnitude. All other loads are variable loads. Lowest adjacent grade (LAG) — Elevation of the lowest natural or re -graded ground surface, or structural fill, that abuts the walls of a building. See Highest adjacent grade. Lowest floor — Under the National Flood Insurance Program, the lowest floor of the lowest enclosed area (including basement) of a structure. An unfinished or flood -resistant enclosure, usable solely for parking of vehicles, building access, or storage in an area other than a basement is not considered a building's lowest floor, provided that the enclosure is not built so as to render the structure in violation of National Flood Insurance Program regulatory requirements. Lowest horizontal structural member — In an elevated building, the lowest beam, joist, or other horizontal member that supports the building. Grade beams installed to support vertical foundation members where they enter the ground are not considered lowest horizontal structural members. Ma — millions of years before present. Magnitude - A measure of the size of an earthquake, as determined by measurements from seismograph records. Major earthquake - Capable of widespread, heavy damage up to 50+ miles from epicenter; generally near Magnitude range 6.5 to 7.0 or greater, but can be less, depending on rupture mechanism, depth of earthquake, location relative to urban centers, etc. Mangrove stand — Under the National Flood Insurance Program, an assemblage of mangrove trees, which are mostly low trees noted for a copious development of interlacing adventitious roots above the ground and which contain one or more of the following species: black mangrove (Avicennia Nitida), red mangrove (Rhizophora Mangle), white mangrove (Languncularia Racemosea), and buttonwood (Conocarpus Erecta). Manufactured home — Under the National Flood Insurance Program, a structure, transportable in one or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when attached to the required utilities. The term "manufactured home" does not include a "recreational vehicle." Marsh — Wetland dominated by herbaceous or non -woody plants often developing in shallow ponds or depressions, river margins, tidal areas, and estuaries. is Earth Consultants International Glossary Page A-10 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Masonry — Built-up construction of combination of building units or materials of clay, shale, concrete, glass, gypsum, stone, or other approved units bonded together with or without mortar or grout or other accepted methods of joining. Maximum Magnitude Earthquake (Mmax) - The highest magnitude earthquake a fault is capable of producing based on physical limitations, such as the length of the fault or fault segment. Maximum Probable Earthquake (MPE) - The design size of the earthquake expected to occur within a time frame of interest, for example within 30 years or 100 years, depending on the purpose, lifetime or importance of the facility. Magnitude/frequency relationships are based on historic seismicity, fault slip rates, or mathematical models. The more critical the facility, the longer the time period considered. Metamorphic rock — A rock whose original mineralogy, texture, or composition has been changed due to the effects of pressure, temperature, or the gain or loss of chemical components. Mean sea level (MSL) — Average height of the sea for all stages of the tide, usually determined from hourly height observations over a 19-year period on an open coast or in adjacent waters having free access to the sea. See National Geodetic Vertical Datum. Metal roof panel — Interlocking metal sheet having a minimum installed weather exposure of 3 square feet persheet. Metal roof shingle — Interlocking metal sheet having an installed weather exposure less than 3 square feet per sheet. • Mitigation — Any action taken to reduce or permanently eliminate the long-term risk to life and property from natural hazards. Mitigation Directorate — Component of Federal Emergency Management Agency directly responsible for administering the flood hazard identification and floodplain management aspects of the National Flood Insurance Program. Moderate earthquake - Capable of causing considerable to severe damage, generally in the range of Magnitude 5.0 to 6.0 (Modified Mercalli Intensity <VI), but highly dependent on rupture mechanism, depth of earthquake, and location relative to urban center, etc. National Flood Insurance Program (NFIP) — Federal program created by Congress in 1965 that makes flood insurance available in communities that enact and enforce satisfactory floodplain management regulations. National Geodetic Vertical Datum (NGVD) — Datum established in 1929 and used as a basis for measuring flood, ground, and structural elevations, previously referred to as Sea Level Datum or Mean Sea Level. The Base Flood Elevations shown on most of the Flood Insurance Rate Maps issued by the Federal Emergency Management Agency are referenced to NGVD or, more recently, to the North American Vertical Datum. Naturally decay -resistant wood — Wood whose composition provides it with some measure of resistance to decay and attack by insects, without preservative treatment (e.g., heartwood of cedar, black locust, black walnut, and redwood). Near -field earthquake - Used to describe a local earthquake within approximately a few fault zone widths of the causative fault which is characterized by high frequency waveforms that are destructive to above -ground • utilities and short period structures (less than about two or three stories). New construction — For the purpose of determining flood insurance rates under the National Flood Earth Consultants International Glossary Page A-11 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Insurance Program, structures for which the start of construction commenced on or after the effective date of . the initial Flood Insurance Rate Map or after December 31, 1974, whichever is later, including any subsequent improvements to such structures. (See Post -FIRM structure.) For floodplain management purposes, new construction means structures for which the start of construction commenced on or after the effective date of a floodplain management regulation adopted by a community and includes any subsequent improvements to such structures. Non -coastal A zone — For the purposes of this manual, the portion of the Special Flood Hazard Area in which the principal source of flooding is runoff from rainfall, snowmelt, or a combination of both. In non - coastal A zones, flood waters may move slowly or rapidly, but waves are usually not a significant threat to buildings. See A zone and coastal A zone. (Note: the National Flood Insurance Program regulations do not differentiate between non -coastal A zones and coastal zones.) Non -load -bearing wall — Wall that does not support vertical loads other than its own weight. See Load - bearing wall. North American Vertical Datum (NAVD) — Datum used as a basis for measuring flood, ground, and structural elevations. NAVD is used in many recent Flood Insurance Studies rather than the National Geodetic Vertical Datum. Oblique — reverse fault — A fault that combines some strike -slip motion with some dip -slip motion in which the upper block, above the fault plane, moves up over the lower block. Offset ridge - A ridge that is discontinuous on account of faulting. Offset stream - A stream displaced laterally or vertically by faulting. (One) 100-year flood — See Base flood. Oriented strand board (OSB) — Mat -formed wood structural panel product composed of thin rectangular wood strands or wafers arranged in oriented layers and bonded with waterproof adhesive. Orthoclase — One of the most common rock -forming minerals; colorless, white, cream -yellow, flesh -reddish, or grayish in color. Paleoseismic — Pertaining to an earthquake or earth vibration that happened decades, centuries, or millennia ago. Peak Ground Acceleration (PGA) - The greatest amplitude of acceleration measured for a single frequency on an earthquake accelerogram. The maximum horizontal ground motion generated by an earthquake. The measure of this motion is the acceleration of gravity (equal to 32 feet per second squared, or 980 centimeter per second squared), and generally expressed as a percentage of gravity. Pedogenic— Pertaining to soil formation. Pegmatite — An igneous rock with extremely large grains, more than a centimeter in diameter. Perched ground water - Unconfined ground water separated from an underlying main body of ground water by an unsaturated zone. Peak flood - The highest discharge or stage value of a flood. 0 Earth Consultants International Glossary Page A-12 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Plagioclase — One of the most common rock forming minerals. Plutonic— Pertaining to igneous rocks formed at great depth. Plywood — Wood structural panel composed of plies of wood veneer arranged in cross -aligned layers. The plies are bonded with an adhesive that cures on application of heat and pressure. Pore pressure - The stress transmitted by the fluid that fills the voids between particles of a soil or rock mass. Post foundation — Foundation consisting of vertical support members set in holes and backfilled with compacted material. Posts are usually made of wood and usually must be braced. Posts are also known as columns, but columns are usually made of concrete or masonry. Post -FIRM structure — For purposes of determining insurance rates under the National Flood Insurance Program, structures for which the start of construction commenced on or after the effective date of an initial Flood Insurance Rate Map or after December 31, 1974, whichever is later, including any subsequent improvements to such structures. This term should not be confused with the term new construction as it is used in floodplain management. Potentially active fault - A fault showing evidence of movement within the last 1.6 million years (750,000 years according to the U.S. Geological Survey) but before about 11,000 years ago, and that is capable of generating damaging earthquakes. Precast concrete — Structural concrete element cast elsewhere than its final position in the structure. See Cast -in -place concrete. . Pressure -treated wood — Wood impregnated under pressure with compounds that reduce the susceptibility of the wood to flame spread or to deterioration caused by fungi, insects, or marine borers. Primary frontal dune — Under the National Flood Insurance Program, a continuous or nearly continuous mound or ridge of sand with relatively steep seaward and landward slopes immediately landward and adjacent to the beach and subject to erosion and overtopping from high tides and waves during major coastal storms. The inland limit of the primary frontal dune occurs at the point where there is a distinct change from a relatively steep slope to a relatively mild slope. Project - A development application involving zone changes, variances, conditional use permits, tentative parcel maps, tentative tract maps, and plan amendments. Quartzite — A metamorphic rock consisting mostly of quartz. Quartz monzonite — A plutonic rock containing major plagioclase, orthoclase and quartz; with increased orthoclase it becomes a granite. Quaternary — The second period of the Cenozoic era, consisting of the Pleistocene and Holocene epochs; covers the last two to three million years. Resonance - Amplification of ground motion frequencies within bands matching the natural frequency of a structure and often causing partial or complete structural collapse, effects may demonstrate minor damage to single -story residential structures while adjacent 3- or 4-story buildings may collapse because of corresponding frequencies, or vice versa. • Recurrence interval — The time between earthquakes of a given magnitude, or within a given magnitude range, on a specific fault or within a specific area. Earth Consultants International Glossary Page A-13 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA Reinforced concrete —Structural concrete reinforced with steel bars. Response spectra - The range of potentially damaging frequencies of a given earthquake applied to a specific site and for a particular building or structure. Retrofit —Any change made to an existing structure to reduce or eliminate damage to that structure from flooding, erosion, high winds, earthquakes, or other hazards. Revetment — Facing of stone, cement, sandbags, or other materials placed on an earthen wall or embankment to protect it from erosion or scour caused by flood waters or wave action Right -lateral fault - A strike -slip fault across which a viewer would see the block on the opposite side of the fault move to the right. Riprap — Broken stone, cut stone blocks, or rubble that is placed on slopes to protect them from erosion or scour caused by flood waters or wave action. Roof deck — Flat or sloped roof surface not including its supporting members or vertical supports. Sand boil - An accumulation of sand resembling a miniature volcano or low volcanic mound produced by the expulsion of liquefied sand to the sediment surface. Also called sand blows, and sand volcanoes. Sand dunes — Under the National Flood Insurance Program, natural or artificial ridges or mounds of sand landward of the beach. Sandstone - A medium -grained, clastic sedimentary rock composed of abundant rounded or angular fragments of sand size set in a fine-grained matrix and more or less firmly united by a cementing material. Saturated - Said of the condition in which the interstices of a material are filled with a liquid, usually water. Scarp —A line of cliffs produced by faulting or by erosion. The term is an abbreviated form of escarpment. Schist —A metamorphic rock characterized by a preferred orientation in grains resulting in the rock's ability to be split into thin flakes or slabs. Scour — Removal of soil or fill material by the flow of flood waters. The term is frequently used to describe storm -induced, localized conical erosion around pilings and other foundation supports where the obstruction of flow increases turbulence. See Erosion. Seawall — Solid barricade built at the water's edge to protect the shore and to prevent inland flooding. Sediment - Solid fragmental material that originates from weathering of rocks and is transported or deposited by air, water, ice, or that accumulates by other natural agents, such as chemical precipitation from solution. and that forms in layers on the Earth's surface in a loose, unconsolidated form. Seiche - A free or standing -wave oscillation of the surface of water in an enclosed or semi -enclosed basin (such as a lake, bay, or harbor), that is initiated chiefly by local changes in atmospheric pressure, aided by winds, tidal currents, and earthquakes, and that continues, pendulum -fashion, for a time after cessation of the originating force. Seismogenic - Capable of producing earthquake activity. 0 Earth Consultants International Glossary Page A-14 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • Seismograph - An instrument that detects, magnifies, and records vibrations of the Earth, especially earthquakes. The resulting record is a seismogram. Shearwall — Load -bearing wall or non -load -bearing wall that transfers in -plane lateral forces from lateral loads acting on a structure to its foundation. Shoreline retreat — Progressive movement of the shoreline in a landward direction caused by the composite effect of all storms considered over decades and centuries (expressed as an annual average erosion rate). Shoreline retreat considers the horizontal component of erosion and is relevant to long-term land use decisions and the siting of buildings. Shutter ridge — That portion of an offset ridge that blocks or "shutters" the adjacent canyon. Silt - A rock fragment or detrital particle smaller than a very fine sand grain and larger than coarse clay, having a diameter in the range of 1/256 to 1/16 mm (4-62 microns, or 0.00016-0.0025 in.). An indurated silt having the texture and composition of shale but lacking its fine lamination is called a siltstone. Single -ply membrane — Roofing membrane that is field -applied with one layer of membrane material (either homogeneous or composite) rather than multiple layers. Sixty (60)-year setback — A state or local requirement that prohibits new construction and certain improvements and repairs to existing coastal buildings located in an area expected to be lost to shoreline retreat over a 60-year period. The inland extent of the area is equal to 60 times the average annual long-term recession rate at a site, measured from a reference feature. • Slope ratio - Refers to the angle or gradient of a slope as the ratio of horizontal units to vertical units. For example, in a 2:1 slope, for every two horizontal units, there is a vertical rise of one unit (equal to a slope angle, from the horizontal, of 26.6 degrees). Slump - A landslide characterized by a shearing and rotary movement of a generally independent mass of rock or earth along a curved slip surface. Soil horizon — A layer of soil that is distinguishable from adjacent layers by characteristic physical properties such as structure, color, or texture. Special Flood Hazard Area (SFHA) — Under the National Flood Insurance Program, an area having special flood, mudslide (i.e., mudflow) and/or flood -related erosion hazards, and shown on a Flood Hazard Boundary Map or Flood Insurance Rate Map as Zone A, AC, Al-A30, AE, A99, AH, V, V1430, VE, M or E. Start of construction (for other than new construction or substantial improvements under the Coastal Barrier Resources Act) — Under the National Flood Insurance Program, date the building permit was issued, provided the actual start of construction, repair, reconstruction, rehabilitation, addition placement, or other improvement was within 180 days of the permit date. The actual start means either the first placement of permanent construction of a structure on a site, such as the pouring of slab or footings, the installation of piles, the construction of columns, or any work beyond the stage of excavation; or the placement of a manufactured home on a foundation. Permanent construction does not include land preparation, such as clearing, grading, and filling; nor does it include the installation of streets and/or walkways; nor does it include excavation for a basement, footings, piers, or foundations or the erection of temporary forms; nor does it include the installation on the property of accessory buildings, Such as garages or sheds not occupied as dwelling units or not part of the main structure. For a substantial improvement, the actual start of • construction means the first alteration of any wall, ceiling, floor, or other structural part of a building, whether or not that alteration affects the external dimensions of the building. Earth Consultants International Glossary Page A-15 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA State Coordinating Agency — Under the National Flood Insurance Program, the agency of the state • government, or other office designated by the Governor of the state or by state statute to assist in the implementation of the National Flood Insurance Program in that state. Stillwater elevation — Projected elevation that flood waters would assume, referenced to the National Geodetic Vertical Datum, North American Vertical Datum, or other datum, in the absence of waves resulting from wind or seismic effects. Storage capacity - Dam storage measured in acre-feet or decameters, including dead storage. Storm surge — Rise in the water surface above normal water level on the open coast due to the action of wind stress and atmospheric pressure on the water surface. Storm tide — Combined effect of storm surge, existing astronomical tide conditions, and breaking wave setup. Strike -slip fault - A fault with a vertical to sub -vertical fault surface that displays evidence of horizontal and opposite displacement. Structural concrete — All concrete used for structural purposes, including plain concrete and reinforced concrete. Structural engineer - A licensed civil engineer certified by the State as qualified to design and supervise the construction of engineered structures. Structural fill — Fill compacted to a specified density to provide structural support or protection to a structure. See Fill. Structure — Something constructed, such as a building, or part of one. For floodplain management purposes under the National flood Insurance Program, a walled and roofed building, including a gas or liquid storage tank, that is principally above ground, as well as a manufactured home. For insurance coverage purposes under the NFIP, structure means a walled and roofed building, other than a gas or liquid storage tank, that is principally above ground and affixed to a permanent site, as well as a manufactured home on a permanent foundation. For the latter purpose, the term includes a building while in the course of construction, alteration, or repair, but does not include building materials or supplies intended for use in such construction, alteration, or repair, unless such materials or supplies are within an enclosed building on the premises. Subsidence - The sudden sinking or gradual downward settling of the Earth's surface with little or no horizontal motion. Substantial damage — Under the National Flood Insurance Program, damage of any origin sustained by a structure whereby the cost of restoring the structure to its before -damaged condition would equal or exceed 50 percent of the market value of the structure before the damage occurred. Substantial improvement — Under the National Flood Insurance Program, any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds 50 percent of the market value of the structure before the start of construction of the improvement. This term includes structures, which have incurred substantial damage, regardless of the actual repair work performed. The term does not, however, include either (1) any project for improvement of a structure to correct existing violations of state or local health, sanitary, or safety code specifications which have been identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions, or (2) any alteration of a "historic structure," provided that the alteration will not preclude the structure's continued Earth Consultants International Glossary Page A-16 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA • designation as a "historic structure." Surge — See Storm surge. Swale — In hillside terrace, a shallow drainage channel, typically with a rounded depression or "hollow" at the head. Thirty (30)-year erosion setback — A state or local requirement that prohibits new construction and certain improvements and repairs to existing coastal buildings located in an area expected to be lost to shoreline retreat over a 30-year period. The inland extent of the area is equal to 30 times the average annual long-term recession rate at a site, measured from a reference feature. Thrust fault — A fault, with a relatively shallow dip, in which the upper block, above the fault plane, moves up over the lower block. Transform system — A system in which faults of plate -boundary dimensions transform into another plate - boundary structure when it ends. Transpression — In crustal deformation, an intermediate stage between compression and strike -slip motion; it occurs in zones with oblique compression. Tropical depression — Tropical cyclone with some rotary circulation at the water surface. With maximum sustained wind speeds of up to 39 miles per hour, it is the second phase in the development of a hurricane. Tropical disturbance — Tropical cyclone that maintains its identity for at least 24 hours and is marked by • moving thunderstorms and with slight or no rotary circulation at the water surface. Winds are not strong. It is a common phenomenon in the tropics and is the first discernable stage in the development of a hurricane. Tsunami — Great sea wave produced by submarine earth movement or volcanic eruption. Typhoon — Name given to a hurricane in the area of the western Pacific Ocean west of 180 degrees longitude. Unconfined aquifer — Aquifer in which the upper surface of the saturated zone is free to rise and fall. Unconsolidated sediments - A deposit that is loosely arranged or unstratified, or whose particles are not cemented together, occurring either at the surface or at depth. Underlayment — One or more layers of felt, sheathing paper, non -bituminous saturated felt, or other approved material over which a steep -sloped roof covering is applied. Undermining — Process whereby the vertical component of erosion or scour exceeds the depth of the base of a building foundation or the level below which the bearing strength of at the foundation is compromised. Uplift — Hydrostatic pressure caused by water under a building. It can be strong enough lift a building off its foundation, especially when the building is not properly anchored to its foundation. Upper bound earthquake — Defined as a 10% chance of exceedance in 100 years, with a statistical return period of 949 years. V zone —See Coastal High Hazard Aiea. Variance — Under the National Flood Insurance Program, grant of relief by a community from the terms of a Earth Consultants International Glossary Page A-17 2003 HAZARDS ASSESSMENT STUDY CITY of NEWPORT BEACH, CALIFORNIA floodplain management regulation. Violation — Under the National Flood Insurance Program, the failure of a structure or other development to be fully compliant with the community's floodplain management regulations. A structure or other development without the elevation certificate, other certifications, or other evidence of compliance required in Sections 60.3(b)(5), (c)(4), (c)(10), (d)(3), (e)(2), (e)(4), or (e)(5) of the NFIP regulations is presumed to be in violation until such time as that documentation is provided. Watershed - A topographically defined region draining into a particular water course. Water surface elevation — Under the National Flood Insurance Program, the height, in relation to the National Geodetic Vertical Datum of 1929 (or other datum, where specified), of floods of various magnitudes and frequencies in the floodplains of coastal or riverine areas. Water table - The upper surface of groundwater saturation of pores and fractures in rock or surficial earth materials. Wave— Ridge, deformation, or undulation of the water surface. Wave crest elevation — Elevation of the crest of a wave. Wave height— Vertical distance between the wave crest and wave trough, Wave runup — Rush of wave water up a slope or structure. Wave runup depth — Vertical distance between the maximum wave runup elevation and the eroded ground elevation. Wave runup elevation — Elevation, referenced to the National Geodetic Vertical Datum or other datum, reached by wave runup. Wave setup — Increase in the stillwater surface near the shoreline, due to the presence of breaking waves. X zone — Under the National Flood Insurance Program, areas where the flood hazard is less than that in the Special Flood Hazard Area. Shaded X zones shown on recent Flood Insurance Rate Maps (8 zones on older maps) designate areas subject to inundation by the 500-year flood. Un-shaded X zones (C zones on older Flood Insurance Rate Maps) designate areas where the annual probability of flooding is less than 0.2 percent. Earth Consultants International Glossary Page A-18 2003 • ►. J Section 6.8 Noise 6.8 Noise • 6.8 NOISE This section describes the environmental noise conditions within the City of Newport Beach Planning Area. Data used in the preparation of this section is based upon various State and Federal sources, field measurements, and modeling of existing noise levels from traffic data in the Planning Area. 0 FUNDAMENTALS OF SOUND AND ENVIRONMENTAL NOISE Sound is technically described in terms of amplitude (loudness) and frequency (pitch). The standard unit of sound amplitude measurement is the decibel (dB). The decibel scale is a logarithmic scale that describes the physical intensity of the pressure vibrations that make up any sound. The pitch of the sound is related to the frequency of the pressure vibration. Since the human ear is not equally sensitive to a given sound level at all frequencies, a special frequency -dependent rating scale has been devised to relate noise to human sensitivity. The A weighted decibel scale (dBA) provides this compensation by discriminating against frequencies in a manner approximating the sensitivity of the human ear. Noise, on the other hand, is typically defined as unwanted sound. A typical noise environment consists of a base of steady ambient noise that is the sum of many distant and indistinguishable noise sources. Superimposed on this background noise is the sound from individual local sources. These can vary from an occasional aircraft or train passing by to virtually continuous noise from, for example, traffic on a major highway. Table 6.8-1 illustrates representative noise levels for the • environment. Several rating scales have been developed to analyze the adverse effect of community noise on people. Since environmental noise fluctuates over time, these scales consider that the effect of noise upon people is largely dependent upon the total acoustical energy content of the noise, as well as the time of day when the noise occurs. Those that are applicable to this analysis are as follows: L,q, the equivalent energy noise level, is the average acoustic energy content of noise for a stated period of time. Thus, the L�q of a time -varying noise and that of a steady noise are the same if they deliver the same acoustic energy to the ear during exposure. For evaluating community impacts, this rating scale does not vary, regardless of whether the noise occurs during the day or the night. CNEL, the Community Noise Equivalent Level, is a 24 hour average LI with a 10 dBA "weighting" added to noise during the hours of 10:00 P.M. to 7:00 A.M., and an additional 5 dBA weighting during the hours of 7:00 P.M. to 10:00 P.M. to account for noise sensitivity in the evening and nighttime. The logarithmic effect of these additions is that a 60 dBA 24-hour kq would result in a measurement of 66.7 dBA CNEL: ■ Lam, the minimum instantaneous noise level experienced during a given period of time ■ I.. the maximum instantaneous noise level experienced during a given period of time General Plan Technical Background Report 6.8-1 Chapter 6 Public Safety Table 6.8.1 Representative Environmental Noise Levels Common ourdoorAeavidls Holso Loveld8A Common lndoorAcdvides —110— Rock Band Jet Flyover at 100 feet —100— Gas Lavmmower at 3 feet —9D— Food Blender at3feet Diesel Truck going 50 mph at 50 feet —60— Garbage Disposal at3feet Noisy Urban Area during Daytime Gas Lawnmower at 100 feel —70— Vacuum Cleaner at 10 feel Commercial Area Normal Speech at 3 feet Heavy Traffic at 300 feet —60-- Large Business Office Quiet Urban Area during Daytime —50— Dishwasher in Next Room Quiet Urban Area during Nighttime —40— Theater, Large Conference Room (background) Quiet Suburban Area during Nighttime —30— Library Quiet Rural Area during Nighttime Bedroom at Night, Concert Hall (background) _2D— BroadcasVRecording Studio Lowest Threshold of Human Hearing —0-- LowestThreshold of Human Hearing Souaca: Cahfomia0epanment ofTransponaUan 19H Noise environments and consequences of human activities are usually well represented by median noise levels during the day, night, or over a 24-hour period. Environmental noise levels are generally considered low when the CNEL is below 55 dBA, moderate in the 55 to 70 dBA range, and high above 70 dBA. Examples of low daytime levels are isolated natural settings that can provide noise levels as low as 20 dBA, and quiet suburban residential streets that can provide noise levels around 40 dBA. Noise levels above 45 dBA at night can disrupt sleep. Examples of moderate level noise environments are urban residential or semi -commercial areas (typically 55 to 60 dBA) and commercial locations (typically 60 dBA). People may consider louder environments adverse, but most will accept the higher levels associated with more noisy urban residential or residential - commercial areas (60 to 75 dBA) or dense urban or industrial areas (65 to 80 dBA). When evaluating changes in 24-hour community noise levels, a 3 dBA increase is barely perceptible to most people. While a 5 dBA increase is readily noticeable, a 10 dBA increase would be perceived as a doubling of loudness.' Noise levels from a particular source decline as distance to the receptor increases. Other factors such as the weather and reflecting or shielding also help intensify or reduce the noise level at any given location. A commonly used rule of thumb for roadway noise is that for every doubling of distance 'US. DOT, Federal HighwayAdminatradon,1980 i is 6.8.2 Clty of Newport Beach 6.8 Noise • from the source, the noise level is reduced by about 3 dBA at acoustically "hard" locations (i.e., the area between the noise source and the receptor is nearly complete asphalt, concrete, hard -packed soil, or other solid materials) and 4.5 dBA at acoustically "soft" locations (i.e., the area between the source and receptor is normal earth or has vegetation including grass). Noise from stationary or point sources is reduced by about 6 dBA to 7.5 dBA for every doubling of distance at acoustically hard and soft locations, respectively. Noise levels may also be reduced by intervening structures —generally, a single row of buildings between the receptor and the noise source reduces the noise level by about 5 dBA, while a solid wall or berm reduces noise levels by 5 to 10 dBA. The manner in which older homes in California were constructed generally provides a reduction of exterior -to -interior noise levels of about 20 dBA with closed windows. The exterior -to -interior reduction of newer homes is generally 30 dBA or more. EXISTING NOISE ENVIRONMENT Sources of Noise Land uses within the Planning Area include a range of residential, commercial, institutional, industrial, recreational, and open space areas. Although other noise sources occur, vehicular traffic is the primary source of noise throughout the Planning Area. Noise also occurs from aircraft overflights from John Wayne Airport and a variety of stationary sources throughout the Planning Area. Coast Highway and Arterial Roadways The dominant noise sources throughout the Planning Area are transportation related. Motor vehicle is noise commonly causes sustained noise levels and often in close proximity of sensitive land uses. The major sources of traffic noise in the Planning Area are Coast Highway, Jamboree Road, and MacArthur Boulevard. Many of the residential uses built near the arterial roadways include some level of noise attenuation, provided by either a sound barrier or grade separation. Other —primarily older —residential uses built near arterial roadways do not have any attenuation from noise other than the distance between the roadway and the residential structure. The noise attenuation features for new residences are reviewed on a project -by -project basis. This means that as residential projects are proposed near the major roadways within the Planning Area, future noise levels are evaluated and noise mitigation strategies are developed as necessary to meet City standards. Aircraft Overflights John Wayne Airport serves both general aviation, and scheduled commercial passenger airline and cargo operations. In the year 2000, John Wayne Airport experienced 387,866 aircraft operations, of which approximately 85,560 were jet air carriers and 15,455 were general aviation jets' The number of average daily departures was just over 130, which included 14 daily departures by commuter aircraft? Although aircraft noise can be heard throughout the Planning Area, the highest noise levels are experienced just south of the airport and are generated by aircraft departures. Portions of the north - central part of the Planning Area are located within the 65 and 60 dBA CNEL noise contours for John Wayne Airport, as shown in Figures 6.8-1(1) to 6.8-1(3). • 'Orange County, John Wayne Airport SetdementAgreement Amendment Draft Environmental Impact Report, 2001. Ibid. General Plan Technical Background Report 6.8.3 Chapter 6 Public Safety Stationary Sources 0 Stationary sources of noise within the Planning Area include common building or home mechanical equipment, such as air conditioners, ventilation systems, or pool pumps; bells and loudspeakers at schools and businesses; and mechanical tools at commercial and industrial facilities. Another stationary source of noise is nightclub operations within the Harbor area. Existing Noise Levels Monitored Daytime Noise Levels Existing ambient daytime noise levels were measured at twenty selected locations on December 18, 2003, and December 19, 2003, in order to identify representative noise levels in various areas of the Planning Area. These locations were identified as unique noise generators within the Planning Area, and shown in Figure 6.8-2. The noise levels were monitored using a Larson -Davis Mode1814 precision sound level meter, which satisfies the American National Standards Institute (ANSI) for general environmental noise measurement instrumentation. The average noise levels and sources of noise measured at each location are identified in Table 6.8-2, The average noise level measurements represent Suburban to Noisy Urban noise levels and are consistent with residential noise levels. In contrast, the maximum noise levels recorded for locations 2 and 3 represent noise levels consistent with City Noise, which reflects a more urban environment. Roadway Noise Levels Existing 24-hour noise levels have been calculated for Coast Highway and various roadways throughout the Planning Area. This task was accomplished using the Federal 'Highway Administration Highway Noise Prediction Model (FHWA-RD-77-108). The model calculates the average noise level at specific locations based on traffic volumes, average speeds, roadway geometry, and site environmental conditions. The average vehicle noise rates (energy rates) utilized in the FHWA Model have been modified to reflect average vehicle noise rates identified for California by Caltrans.' The Caltrans data show that California automobile noise is 0.8 to 1.0 dBA higher than national levels and that medium and heavy truck noise is 0.3 to 3.0 dBA lower than national levels.' Noise levels were modeled for Coast Highway and the roadways with the highest traffic volumes within the Planning Area. The calculated noise levels are presented in Table 6.8-3 along with the distances to various noise level contours. Based on this formation, Coast Highway, Jamboree Road, and MacArthur Boulevard are the greatest sources of noise within the Planning Area. Existing residential uses in close proximity to these highway and roadway segments could be exposed to high noise levels on a regular basis. Existing roadway noise contours are shown in Figures 6.8-1(1) to 6.8-1(3). ' Hendrikc 1987 • ' Ibid. 6.84 CV of Newport Beach . 1 CITY of NEWPORT BEACH E GENERAL PLAN Figure 6.6-1 (1) EXISTING ROADWAY (2003) J5 NOISE CONTOURS a BANNING �. ¢' RANCH . ¢1 •.• Cfly Boundary 60CNEL i V ••v ¢ : � � o • — 65 CNEL •a Pc 6 T • .,,7 `. r... �o�' -. \�? T 70 CNEL s NEWPORT SHORES 1' SANTA ANA •••• • i ,`�•.' )C RIVER JETTY�- M� SP AD A4 o 4 Yy < �S NORTH STAR may* A' fit` BEACH G Stale Plore, Zpe 6. N<D83, fuel. . O z B a b 4C 6 � m t O — viF C4 p UO NEVVPORT FASHION S� -I DUNES ISLAND LISLE ON ND F HARBOR LIDO ISLAND O �� ISLE w / COLLINS 2 �: INDEX NEWPORT ISLAND O PIER BAY T ISLAND hP l"Y BALBOA ISLAND 0 1000 20DO Feet 0 0.25 0.5 BALBOA A—�� PIER is MISS aEtlek O Source:Cllyof NeV.n Su Beu. CBy BgnEay, S, 2003. i. R May 2W3: % Census Bureau, W E City BaxWarN 20W: ESRI. .'� Nopr m L F- . DVMW a C AR , Gis. NOLm MunttghsD 5 Feb r 17, 2 n. Dldlttetl Nuke Cmbus, GIB Rogrom. Feaniwy i], 2W4. PROJECT NUMBER: 10579-01 Requested by: HR Created by: MV Date: 03/03/04 F T P HE L 1 1 e WEDGE BIG CORONA '•�� V U CITY of NEWPORT BEACH GENERAL PLAN Figure 6,6-1 (2) EXISTING ROADWAY (2003) NOISE CONTOURS - - Cty Boundory 60 CNEL — 65 CNEL -- 70 CNEL Airport Q� Wo GISO IVOIBcMn -U Sbe Plane. ZW 6.N OFeet (2) INDEX 0 1000 2000 Feet 0 l4� o zs 0.5 Mlles Stoics: CXy of Now" Bead, CA/ Boinday, Moy 2003, Co ire% May 20D3: US Ce Bureau, Omer CBy Boundo , 2000: ESRI, Maly Ra Fel n ry 2002: and EIP Aaocbfes. DloI Nobs Contours, GIS Program, February 17, 20 . PROJECT NUMBER: 10579-01 Requested by: HR Created by: MV Date: 2/ 18/04 EIP CITY of NEWPORT BEACH GENERAL PLAN Figure 6.6-1 (3) EXISTING ROADWAY (2003) NOISE CONTOURS ••-•- CNBoundary 60 CNEL — 65 CNEL 70 CNEL Q Nora: Gtis Doa PgecBoil cwstare Wore. rare a Nwea. Feet. _ (3) INDEX 0 1000 2000 Feet 0 0.25 0.5 K1M Scarce: COY of Newpod Beach, CRY bovWar/. mw 2003. C. mfl., Mw 200.3; OB Ce/mre Bueao. Ohm COY Boutoct m 200D; ESM. Molar RooaL Feb u 2002; o wModc6m, Dlgmw N w C.. G5 Rropam. Feduory 17. 2DD4. PROJECT NUMBER: 10579-01 Requested by: HR Created by: MV Date: 2/18/04 EIP CITY of NEWPORT BEACH GENERAL PLAN COSTA MESA BANNING _ __- RANCH NEWPORT.. It- SHORES NLWPORT ' VIER i IRVINE 41 Ji 4 NORTH _f". \,.1 i f__ l'-1 l `�("1it; ,�,�>;• ,/•lam -(`-'-ram \'/�' I� t-r`� -�- 1 � �%� ~--/�'�'" � �,�1 I t NEWPORT /1 \ Trl r`i „ t , y a RIDGE SI Oa NEWYORT1 LrvA,a=rv l 3 DONFS `. - I FASHION h' \�` ` �' _ �' O`',`•. ; ter.,,.- ,_,..'1 i co ISLAND ,✓o C1 1 4:. ISIE.- 1 _` \ i /Y •1ST ` 7 . j - 11 , 1, \ w's LIDO�O/,i//�,�+`HARBORhfO pG'`•-.1 w ISLE 4 /T',4/ IsunD �`• t',I,1-'1 — �_ p� /--. h 1..� _ Tch; SC�\ i2 - - },/! - :.Iti^-.�-- •� COLLINS ��} ,' C '=� _ " 15 LAr - 1\:- 1 4.' L HELs ._, �-� ,;_% 1` 11 ~eALBOA aurvo t'� IERIOA 12 C/,;, wTocE �'_ eIc '- EWPORT u �,1 LITTLE �- NOAST a.• COAST •o- CORONA � \' 1 CAMEO ' NEwPOAT LHOREs CRYSTAL COVE STATE PARK :.w CRYSTAL COVE STATE PARK Figure 6.8-2 NOISE MEASUREMENT LOCATIONS - City Boundary Noise Measurement Location, �P Hoag Hospital z0 127 41 st Street -Comer of BalboaO Boulevard 204 Via Mfibes-Comer of Via Lido Nord Q 601 Via Lido Nord -Comer of Via Orvieto Qe Park at Look Out Point 0 Adjacent to331 Mayflower-Deonza Trailer Park 0 Southwest comer of Patolita Road and Bonnie Doane Terrace Qa Comer of Park Road and Onyx Road 214 Coronado Road 10 End of Adams Road 13 Vacant Lot on Bayside Drive 0 Front Yard of 415 1/2 Marguerite Avenue r3 Crystal Cove Commercial Center -next to housing at south end of parking lot 9 Adjacent to Newport Beach Fire Department is Comer of Pt. Conception and El Capstan 16 North of Sausalito Street on Marguerite Avenue 17 Intersection of San Miguel Drive and Yacht Coquette 1E 500 yards east of MacArthur Boulevard on Bonita Canyon Drive rs Eastbluff Drive N.E. of Vista Del Oro zo Bison and Belcourt Drive North Note: GIS Data Projection - CA State Plane, Zone 6, NAD83. Feet. 0 2000 4000 Feet 0 a5 1 Mies Source: City of Newport Beach, General Plan, July 2003, City Boundary. May 2003. Count es, May 2003, CI& Faclidies, October 20D3; US Census Bureau, Other CM Boundaries, 2000, ESRI, Moja Roads, February 2002; and EIP Assoclotes, GIS Program, November, 2003 PROJECT NUMBER:10579-01 Request by. HR Created by. MV Date: 12/26/03 f,' l� AS so cI ATes 6.8 Noise • • • Table 6.8.2 Existing Daytime Noise Levels at Selected Locations Norse MessurenentLoc®aon '' PdmeryNolse Sources Natse'L'eVelSfeflsOcs L. I Limn I L.. 1. Hoag Hospital Traffic on Newport Beach Boulevard 55.6 49.5 63.3 2.127 41st Street -Comer of Balboa Boulevard Traffic anBalboa Boulevard 67.4 48.0 77.9 3.204 Via Antibes -Comer of Via Lido Nord Traffic on Via Lido Nord 59.4 44.1 77.2 4.601 Via Lido Nord -Corner of Via Orvieto Traffic on Via Orvieto 58.9 41.0 75.8 5. Park at Look Out Point Traffic on Coast Highway 61.6 53.8 82.5 6. Adjacent to 331 Mayflower-Deanza Trailer Park Traffic on Coast Highway 58.4 45.9 70.5 7. Southwest corner of Patolila Road and Bonnie Doone Terrace Traffic on Coast Highway 58.2 45.1 67.6 8. Comer of Park Road and Onyx Road Traffic on Park Road 61.7 45.2 78.8 9.214 Coronado Road Traffic on Balboa Boulevard 63.1 48.0 77.4 10. End of Adams Road Boating facilities 60.5 50.3 78.7 11. Vacant Lot on Bayside Drive Traffic on Bayside Drive 59.4 42.4 69.9 12. Front Yard of 415Y2 Marguerite Avenue Traffic on Marguerite Avenue 60.5 50.0 75.6 13.Crystal Cove Commercial Center -next to housing at south end of parking lot Commercial use activities 56.0 1 43.0 1 72.4 14. Adjacent to Newport Beach Fire Department Traffic on Newport Coast Drive 61.8 47.0 81.1 15. Corner of Pt. Conception and El Capitan Traffic on San Joaquin Road 40.2 33.4 53.8 16. North of Sausalito Street on Marguerite Avenue Traffic onMarguerite Avenue 66.0 41.8 82.3 W. Intersection of San Miguel Drive and Yacht Coquette Traffic on San Miguel Drive 66.1 47.2 85.2 18. 600 yards east of MacArthur Boulevard on Bonita Canyon Drive Traffic on Bonita Canyon Drive 64.9, 53.2 75.1 19. Eastbluff Drive N.E. of Vista Del Oro Traffic on Eastbluff Drive 62.8 47.0 73.0 20. Bison and Belcourt Drive North Traffic on Bison 63.3 50.4 78.9 Some: EIP Associates 2003. Noise monitoring records are provided in Appendix A. Noise levels ware monitored for 15 minutes at each location on December 18 and 19, 2003. Table 6.8.3 Existing Roadway Noise Levels Roadway RoadwaySegmenf .Relbrong1da of 100 Fear Drstence to Noise Contourb 70 Ldn Os Ldn . OOLdn 16th Street Irvine Avenue to Dover Drive 56.7 - - 52 32nd Street West of Newport Boulevard 57.7 - - 71 32nd Street East of Newport Boulevard 53.5 - - - AvocadoAvenue North of San Miguel Drive 54.6 - - 44 Avocado Avenue South of San Miguel Drive 62.2 - 65 140 Avocado Avenue Noah of Coast Highway 61.8 - 61 132 Balboa Boulevard South of Coast Highway 60.3 - 48 104 Bayside Drive South of Coast Highway 57.8 - - 71 Birch Street Jamboree Road to Von Karman Avenue 61.0 - 54 116 Birch Street Von Karman Avenue to MacArthur Boulevard 61.9 - 63 135 Birch Street West of MacArthur Boulevard 62.2 - 65 141 Birch Sliest North of Bristol Street North 63.8 - 83 179 Birch Street Bristol Street North to Bristol Street South 63.0 - 73 158 Birch Street South of Bristol Street South 61.9 - 63 135 General Plan Technical Background Report 6.8-13 Chapter 6 Public Safety Table 6.8.3 Existing Roadway Noise Levels Radwey Roedwry Seament Rofwnce Lan it 100 F"P elftance to Rope conteud 70 Lan d$Ldn 60 Len Bison Avenue Jamboree Road to MacArthur Boulevard 61.6 - - 128 Bison Avenue MacArthur Boulevard to SR-73 Freeway 68.9 - 84 Bonita Canyon Drive East of MacArthur Boulevard 66.7 60 130 279 Bonita Canyon Drive West of SR-73Freeway 64.8 - 98 210 Bristol Street North 'West of Campus Drive 64.6 - 94 202 Bristol Street North Campus Drive to Birch Street 63.7 - 82 177 Bristol Street Noah Eastof Birch Street 63,5 - 80 172 Bristol Street North West of Jamboree Road 62.1 - 64 138 Bristol Street South West of Campus DrivellrvineAvenue 64.6 - 94 202 Bristol Street South Campus Drive to Birch Street 62A - 67 145 Bristol Street South East of Birch Street 62.1 - 64 139 Bristol Street South West of Jamboree Road 65.0 47 100 216 Campus Drive Jamboree Road to Von Kerman Avenue 63.5 - 79 170 Campus Drive Von Korman Avenue to MacArthur Boulevard 64A - 92 197 Campus Drive West ofMacAahurBoulevard 65.6 51 109 235 Campus Drive North of Bristol Street North 65.9 53 115 247 Cam5HIghWay Bristol Street North to Bristol Street South 66.2 56 120 258 Coay West of151hStreet 70.2 103 222 479 Coa 159, Street to Bluff Road 70.5 107 231 498 Coay Bluff Road to SuperiorAvenue/BalboaAvenue 70.5 107 231 498 Coay Superior Avenue to Newport Boulevard 65.8 79 171 368 Coay Newport Avenue to Riverside Avenue 71.1 118 254 548 Coast Highway R verside Avenue to Tustin Avenue 70.2 103 223 480 Coast Highway Tustln Avenue to Dover Drive 69.9 99 213 459 Coast Highway Dover Drive to Bayside Drive 71.6 127 274 591 Coast Highway BaysideDrive toJamboree Road 71.1 118 1255 549 Coast Highway Jamboree Road to Newport Center Drive 70.5 107 232' 499 Coast Highway Newport Center Drive to Avocado Avenue 69.3 89 193 415 Coast Highway Avocado Avenue to MacArthur Boulevard 69.4 91 196 423 Coast Highway MacArthur Boulevard to Goldenrod Avenue 69.6 94 203 436 Coast Highway Goldenrod Avenue to Marguerite Avenue 69.3 90 194 417 Coast Highway Marguerite Avenue to Poppy Avenue 69.0 86 185 399 Coast Highway PoppyAvenue to Newport Coast Drive 68.3 77 166 358 Coast Highway East of Newport Coast Ddve 69.3 69 193 415 DoverDrive Irvine Avenue toWasldfffDdve 67.1 - - 65 Dover Drive Wesldiff Drive to Oh Street 63.4 36 79 169 Dover Drive 161, Street to Cliff Drive 64.0 40 86 184 Dover Drive Cliff Drive to Coast Highway 64.6 44 94 204 Eastbluff Drive West of Jamboree Road at University Ddve 61A - 58 1 124 EaslbluffDrive West of Jamboree Road at Ford Road 63.3 - 77 166 Ford Road Jamboree Road to MacArthur Boulevard 61.0 - 54 1116 Goldenrod Avenue North of Coast Highway 54.2 - - 41 • • • 6.8-14 CifyofNewport Beach 6.8 Noise • • • Table 6.8.3 Existing Roadway Noise Levels Roadway RoadwaySegmenf Reference Ldn af,100 Feel- Distance to Rolio Cdi fouO 70 Len 65 Ldn 60 Lan Highland Drive East of Irvine Avenue 54.2 - - 41 Hospital Road Placentia Avenue to Newport Boulevard 66.0 - - 100 Hospital Road East of Newport Boulevard 57.3 - - 66 Irvine Avenue Bristol Street South to Mesa Drive 63.2 - 75 162 Irvine Avenue Mesa Drive to University Drive 63,8 - 83 178 Irvine Avenue University Drive to Santa Isabel Avenue 64.0 - 86 186 Irvine Avenue Santa Isabel Avenue to Santiago Drive 63.5 - 79 170 Irvine Avenue Santiago Drive to Highland Drive 63.2 - 75 162 Irvine Avenue Highland Drive to Dover Drive 63.2 - 75 162 Irvine Avenue Dover Drive to Westclrff Drive 62.3 - 66 142 Irvine Avenue Westcliff Drive to 161h Street 59.6 - - 95 Jamboree Road Campus Drive to Birch Street 69.4 91 196 423 Jamboree Road Birch Street to MacArthur Boulevard 70.1 101 218 469 Jamboree Road MacArthur Boulevard to Bristol Street North 69.4 91 196 423 Jamboree Road Bristol Street North to Bristol Street South 70.6 109 235 506 Jamboree Road Bristol Street South to Bayview Way 70.6 109 235 506 Jamboree Road Bayview Way to University Drive 70.6 109 235 508 Jamboree Road University Drive to Bison Avenue 69.5 93 200 431 Jamboree Road Bison Avenue to Ford Road 69.7 96 207 446 Jamboree Road Ford Road to San Joaquin Hills Road 70.5 107 231 498 Jamboree Road San Joaquin Hills Road to Santa Barbara Road 69.2 88 189 407 Jamboree Road Santa Barbara Road to Coast Highway 68.9 84 182 391 Jamboree Road Coast Highway to Bayside Drive 64.4 - 91 196 MacArthur Boulevard Campus Drive to Birch Street 68.1 75 162 349 MacArthur Boulevard Birch Street to Von Kansan Avenue 67.3 66 141 305 MacArthur Boulevard Von Karmen Avenue to Jamboree Road 68.0 73 158 341 MacArthur Boulevard South of Jamboree Road 68.1 75 162 349 MacArthur Boulevard North of Bison Avenue ' 71.7 130 279 602 MacArthur Boulevard Bison Avenue to Ford Road 72.2 141 303 654 MacArthur Boulevard Ford Road to San Joaquin Hills Road 71.6 127 274 590 MacArthur Boulevard San Joaquin Road to San Miguel Road 69.7 95 205 442 MacArthur Boulevard San Miguel Road to Coast Highway 68.7 83 178 383 Marguerite Avenue South of San Joaquin Hills Road 59.9 - - 98 Marguerite Avenue North of Coast Highway 59.0 - 40 86 Mesa Drive East of Irvine Drive 61.0 - 54 116 Newport Boulevard North of Hospital Road 63.6 - 81 174 Newport Boulevard Hospital Road to Coast Highway 64.4 - 91 196 Newport Boulevard Coast Highway toVia Udo 64.9 - 98 211 Newport Boulevard Via Lido to 32nd Street 63.6 - 71 174 Newport Boulevard South of 32nd Street 62.7 - 70 151 Newport Center Drive North of Coast Highway 63.1 - 75 162 Newport Coast Drive SR-73 Freeway to San Joaquin Hills Road 62.5 - 68 147 General Plan Technical Background Report 6.8-15 Chapter 6 Public Safety Table 6.8.3 Existing Roadway Noise Levels Roadway Roadweysegmenf Reference Ian of 100F"r Distance to Notre Confoud 7011.dn 65 Lan Md. Newport CoastDdve South of San Joaquin Hills Road 62.2 - 65 105 Newport Coast Drive North of Coast Highway 61.2 - - 121 Placentia Avenue North ofSdperiorAvenue 61.0 - 64 116 Placentia Avenue SupedorAvenuetoHospital Road 58.6 - - 81 Poppy Avenue North of Coast Highway 53.0 - - 34 Riverside Avenue North of Coast Highway 57.1 - - 65 San Joaquin Hills Road Jamboree Road to Santa Cruz Road 63.7 - 82 177 San Joaquin Hills Road Santa Cruz Road to Santa Rose Road 62.1 - 64 138 San Joaquin Hills Road Santa Rosa Road to MacArthur Boulevard 64.9 - 98 212 San Joaquin Hills Road MacArthur Boulevard to San Miguel Road 64.3 - 90 194 San Joaquin Hills Road San Miguel Road to Marguerite Avenue 64.2 - 89 191 San Joaquin Hills Road Marguerite Avenue to Spyglass Hill Road 62.5 68 146 San Joaquin Hills Road Spyglass Hill Road to Newport Coast Drive 62.2 - 65 140 San Miguel Ddve North of Spyglass Hill Road 58.6 - - 81 Sere Miguel Ddve South of Spyglass Hill Road 58.8 - - 81 San Miguel Ddve North of San Joaquin Hills Road 61.0 - 54 116 San Miguel Drive San Joaquin Hills Road to MacArthur Boulevard 62.2 - 65 140 San Miguel Drive MacArthur Boulevard to Avocado Avenue 64.2 - 88 191 San Miguel Drive West of Avocado Avenue 61.4 - 68 1Y4 Santa Barbara Drive East of Jamboree Road 60.2 - - 103 Santa Cruz Drive South of San Joaquin Hills Road 59.2 - - 89 Santa Rosa Drive South of San Joaquin Hills Road 60.6 - 51 110 Santiago Drive Tustin Avenue to Irvine Avenue 58.3 - - 77 Santiago Drive East of Irvine Drive 56.0 - - 64 Spyglass Hill Road San Miguel Drive to San Joaquin Hills Road 56.1 - - 55 Superior Avenue North of Placentia Avenue 625 - 68 147 SupedorAvenue Placentia Avenue toHospital Road 63.6 - 81 174 SuperiorAvenue Hospital Road to Coast Highway 64.0 - 86 184 Tustin Avenue North of Coast Highway 63.0 - - 34 University Drive East of[Wine Avenue 58.3 - - 78 University Drive East of Jamboree Road 64.0 - 86 185 Via Lido East of Newport Boulevard 57.9 - - 72 Von Kansan Avenue Campus Drive to Birch Street 61.6 - 60 129 Von Kerman Avenue Birch Steel to MacArthur Boulevard 61.0 - 54 116 Westcliff Drive Irvine Avenue to Dover Drive 60.9 - 53 115 SOURCE: EIP AerALlalea 2003. Calculation data and msuils am provided lnAppsnckA. Dislances am In Wt from madway, centedlne.The idenVed noise level at 100 foal from He roadwaycenledina Is for reference purposes only as a point tram which to calculate the noise contourdistances. II does riolmtect an actual burring location or potential impact location. e _Noise contourls located within the roadway lanes. • • • 6.8.16 City of Newport Beach 6.8 Noise • Special Noise Sources Construction activities are a regular and on -going source of noise throughout the Planning Area. The noise levels generated by construction activities are generally isolated to the immediate vicinity of the construction site and occur during daytime hours in accordance with City regulations (discussed below). Construction activities also occur for relatively short-term periods of a few weeks to a few months, and then, the noise sources are removed from the construction area. The Harbor area is a mix of residential and commercial land uses; often located in close proximity to each other. Noise is generated on a regular basis by nighttime restaurant activities within commercial uses. Sometimes these nighttime activities generate noise levels that disturb nearby residents when they are trying to sleep and result in complaints filed with the City Police Department. Residences throughout the Planning Area are also known to occasionally generate noise from parties that result in complaints filed with the local authorities. Sensitive Receptors Various standards have been developed to address the compatibility of land uses and noise levels. The applicable standards are presented in the following discussion. Special emphasis is placed on land uses that are considered to be sensitive to high noise levels. From a noise perspective, typical sensitive receptors include residences, schools, child care centers, hospitals, long-term health care facilities, convalescent centers, and retirement homes. Each of these land use types currently occur within the Planning Area. •M REGULATORY SETTING Federal Regulations There are no Federal noise requirements or regulations that bear directly on local actions of the County and City. However, there are Federal regulations that influence the audible landscape, especially for projects where Federal funding is involved. The Federal Highway Administration (FHWA) requires abatement of highway traffic noise for highway projects through rules in the Code of Federal Regulations (23 CFR Part 772), and the Federal Transit Administration (FTA) and Federal Railroad Administration (FRA) each recommend thorough noise and vibration assessments through comprehensive guidelines for any mass transit or high-speed railroad projects that would pass by residential areas. For housing constructed with assistance from the U.S. Department of Housing and Urban Development, minimum noise insulation standards must be achieved (24 CFR Part 51, Subpart B). The FAA has prepared guidelines for acceptable noise exposure in its FAR Part 150 Noise Compatibility Planning program for airports. According to the Part 150 guidelines, exterior aircraft exposures of 65 dBA CNEL or less and an interior exposure 45 dBA CNEL or less are considered acceptable for residential uses.' These standards apply to the operation of John Wayne Airport. • `Although the noise standards identified by the FAA are based on La„ levels, CNEL is used in this EIR Noise levels based on CNEL are generally less than 1.0 dBA less than Ld,,. General Plan Technical Background Report 6.8-17 Chapter 6 Publlc Safety State Regulations The State of California, Governor's Office of Planning and Research has published recommended guidelines for mobile source noise and land use compatibility! Each jurisdiction is required to consider these guidelines when developing its General Plan noise element and determining the acceptable noise levels within its community. The land use compatibility standards for community noise levels recommended in the guidelines are identified in Title 24 of the California Code of Regulations establishes California Noise Insulation Standards, which identify an interior noise standard of 45 dBA CNEL for new multi -family residential units. This standard would apply to all new townhomes, condominiums, apartments, hotels, and motels developed within the Planning Area. Local Regulations City of Newport Beach Municipal Code The City of Newport Beach has also adopted noise regulations (Chapter 10.26 of the Newport Beach Municipal Code), which identify specific noise restrictions, exemptions, and variances for sources of noise within the city. Section 10.28.010 of the City Municipal Code regulates what is considered loud and unreasonable noise as follows: It is unlawful for any person or property owner to willfully make, allow, continue or cause to be made, allowed, or continued, any loud and unreasonable, unnecessary, or disturbing noise, including, but not limited to, yelling, shouting, hooting, whistling, singing, playing music, or playing a musical instrument, which disturbs the peace, comfort, quiet or repose of any area or which causes discomfort or annoyance to any reasonable person of normal sensitivities in the area, after a peace or code enforcement officer has first requested that the person or property owner cease and desist from making or continuing, or causing to make or continue, such loud, unreasonable, unnecessary, excessive or disturbing noise In addition, the City has adopted an ordinance to regulate noise levels during construction (City of Newport Beach, Municipal Code Section 10.28.040). The hours of limitation for construction activities are specified in Section 10.28.040 of the Municipal Code as follows: A. Weekdays and Saturdays. No person shall, while engaged in construction, remodeling, digging, grading, demolition, painting, plastering or any other related building activity, operate any tool, equipment or machine in a manner which produces loud noise that disturbs, or could disturb, a person of normal sensitivity who works or resides in the vicinity, on any weekday except benvecn the hours of seven a.m. and six -thirty p,m., nor on any Saturday except between the hours of eight a,m. and six p.m. B. Sundays and Holidays. No person shall, while engaged in construction, remodeling, digging, grading, demolition, painting, plastering or any other related building activity, operate any tool, equipment or machine in a manner which produces loud noise that disturbs, or could disturb, a person of normal sensitivity who works or resides in the vicinity, on any Sunday or any Federal holiday. ' California, Govemor's Offim of Planning and Research, 1998 0 6.8-18 City of Newport Beach 6.8 Noise • ■ REFERENCES Barry, T.M. and J.A. Reagan. 1978. FHWA Highway Traffic Noise Prediction Model (FHWA-RD- 77-108). CJ • California. Governor's Office of Planning and Research. 12002998. General Plan Guidelines, Appendix A: Guidelines for the Preparation and Content of the Noise Element of the General Plan. Hendriks, Rudolf W. 1987. California Vehicle Noise Emission Levels (FHWA/CA/TL-87/03). Newport Beach, City of. 1994. Noise Element, City of Newport Beach General Plan. Chapter 11.44. Ord. 89-29, 23 January 1990. Orange, County of. 2001. John Wayne Airport Settlement Agreement Amendment Draft Environmental Impact Report. U.S. ' Department of Transportation. Federal Highway Administration. 1980. Highway Noise Fundamentals. General Plan Technical Background Report 6.8-19 • � Appendix A NOISE DATA • • • Sound Level Meter Summary Translated: 08-Mar-2004 14:13:44 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Documents\Projects\10579-01 Newport Beach GP\Noise Monitoring Data\Location l.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 1 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 49.5 Max: 63.3 Peak-1: 90.8 Peak-2: 81.0 L (1.67) 61.3 L (8.33) 58.7 L (33.33) 55.5 L (50.00) 54.4 L (66.67) 53.4 L (90.00) 51.8 18-Dec-2003 11:37:47 00:15:01.2 55.6 85.2 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 11:46:03 18-Dec-2003 11:44:12 18-Dec-2003 11:44:16 18-Dec-2003 11:40:58 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: Checked: Calibrator: Level: Cal Record Count: Interval Records: Time History: 12-Dec-2003 15:24:31 12-Dec-2003 15:24:31 LD 0504 114.0 6 Enabled Enabled • Free Memory: 524288 290553 Free Memory: 290553 Battery Level: 75% Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 49.5 Max: 63.3 Peak-1: 90.8 Peak-2: 81.0 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times 18-Dec-2003 11:38:41 00:15:00.0 55.6 85.2 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 11:46:03 18-Dec-2003 11:44:12 18-Dec-2003 11:44:16 18-Dec-2003 11:40:58 Pause Time: 00:00:00.0 Offset: 8.8 dB Level: 91.9 dB Number Interval Records: Number History Records: Percent Free: 55.42% Source: INT 2 21 Sound Level Meter Summary Translated: 08-Mar-2004 14:14:04 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Newport Beach GP\Noise Monitoring Data\Location 2.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 2 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 48.0 Max: 77.9 Peak-1: 99.6 Peak-2: 91.9 L (1.67) 73.9 L (8.33) 72.0 L (33.33) 67.1 L (50.00) 64.8 L (66.67) 61.8 L (90.00) 56.4 18-Dec-2003 12:09:26 00:15:00.0 67.4 97.0 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 12:23:59 18-Dec-2003 12:10:33 18-Dec-2003 12:16:46 18-Dec-2003 12:10:32 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: Checked: Calibrator: Level: Cal Record Count: Interval Records: Time History: 814 Memory: Free Memory: Battery Level: Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: criterion: Exchange Rate: Min: 48.0 Max, 77.9 Peak-1: 99.6 Peak-2: 91.9 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Documents\Projects\10579-01 18-Dec-2003 12:09:26 00:15:00.0 67.4 97.0 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 12:23:59 18-Dec-2003 12:10:33 18-Dec-2003 12:16:46 18-Dec-2003 12:10:32 Pause Time: 00:00:00.0 12-Dec-2003 15:24:31 Offset: 8.8 dB 12-Dec-2003 15:24:31 Level: 91.9 dB LD 0504 114.0 0 Enabled Number Interval Records: Enabled Number History Records: 524288 290553 Percent Free: 55.42% 73% Source: INT 1 18 i • • • Sound Level Meter Summary Translated: 08-Mar-2004 14:14:22 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Newport Beach GP\Noise Monitoring Data\Location 3.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Deacr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute octave Filters: None Location: Newport Beach Location 3 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 44.1 Max: 77.2 Peak-1: 100.4 Peak-2: 90.3 L (1.67) 68.6 L (8.33) 62.7 L (33.33) 56.9 L (50.00) 53.5 L (66.67) 49.9 L (90.00) 47.3 18-Dec-2003 12:37:28 00:15:00.0 59.4 89.0 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 12:49:16 18-Dec-2003 12:44:36 18-Dec-2003 12:44:35 18-Dec-2003 12:44:34 Detector: Slow Weighting: A oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: Checked: Calibrator: Level: Cal Record Count: Interval Records: Time History: 814 Memory: Free Memory: Battery Level: Start Time Elapsed Time Leg: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 44.1 Max: 77.2 Peak-1: 100.4 Peak-2: 90.3 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Documents\Projects\10579-01 18-Dec-2003 12:37:28 00:15:00.0 59.4 89.0 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 12:49:16 18-Dec-2003 12:44:36 18-Dec-2003 12:44:35 18-Dec-2003 12:44:34 Pause Time: 00:00:00.0 12-Dec-2003 15:24:31 O££set: 8.8 dB 12-Dec-2003 15:24:jl Level: 91.9 dB LD 0504 114.0 0 Enabled Number Interval Records: 1 Enabled Number History Records: 18 524288 290553 Percent Free: 55.42% 72% Source: INT Sound Level Meter Summary Translated: 08-Mar-2004 14:14:35 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Newport Beach GP\Noise Monitoring Data\Location 4.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angelesp CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 4 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion; Exchange Rate: Min: 41.0 Max: 75.8 Peak-1: 100.8 Peak-2: 88.6 L (1.67) 67.4, L (8.33) 62.4 L (33.33) 57.3 L (50.00) 55.5 L (66.67) 53.1 L (90.00) 48.0 18-Dec-2003 12:57:01 00:15:00.0 58.9 88.5 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 13:02:28 18-Dec-2003 12:59:07 18-Dec-2003 12:59:07 18-Dec-2003 12:59:07 Detector: Slow Weighting: A Oba Filter: 1000 H2 SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 41.0 Max: 75.8 Peak-1: 100.8 Peak-2: 88.6 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Documents\Projects\10579-01 18-Dec-2003 12:57:01 00:15:00.0 58.9 88.5 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 13:02:28 18-Dec-2003 12:59:07 18-Dec-2003 12:59:07 18-Dec-2003 12:59:07 Pause Time: 00:00:00.0 Calibrated: 12-Dec-2003 15:24:31 Offset: 8.8 dB Checked: 12-Dec-2003 15:24:31 Level: 91.9 dB Calibrator: LD 0504 Level: 114.0 Cal Record Count: 0 Interval Records: Enabled Number Interval Records: 1 Time History: Enabled Number History Records: 18 814 Memory: 52928E Free Memory: 290553 Percent Free: 55.928 Battery Level: 71% Source: INT 0 Sound Level Meter Summary • Translated: 08-Mar-2004 14:14:49 -------------------------------------------------------------------------------- File Translated: C:\Documents and Settings\MBrown.LAV-1\My Documents\Projects\10579-01 Newport Beach GP\Noise Monitoring Data\Location 5.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 5 Note 1: Note 2: Overall Measurement Current Measurement --------------------------------------- Start Time: 18-Dec-2003 13:25:22 --------------------------------------- Start Time 18-Dec-2003 13:25:22 Elapsed Time: 00:15:00.0 Elapsed Time 00:15:00.0 Leq: 61.6 Leq: 61.6 SEL: 91.2 SEL: 91.2 Dose: 0.00 Dose: 0.00 Proj. Dose: 0.00 Proj. Dose: 0.00 Threshold: 0 dB Threshold: 0 dB Criterion: 0 dB Criterion: 0 dB Exchange Rate: 3 dB Exchange Rate: 3 dB Min: 53.8 18-Dec-2003 13:29:09 Min: 53.8 18-Dec-2003 13:29:09 Max: 82.5 18-Dec-2003 13:31:54 Max: 82.5 18-Dec-2003 13:31:54 • Peak-1: 107.8 18-Dec-2003 13:31:53 Peak-1: 107.8 18-Dec-2003 13:31:53 Peak-2: 97.2 18-Dec-2003 13:31:00 Peak-2: 97.2 18-Dec-2003 13:31:00 L (1.67) 66.0 L (8.33) 61.8 L (33.33) 60.0 L (50.00) 59.2 L (66.67) 58.5 L (90.00) 57.1 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 Exceeded: 0 times SPL Exceedance Level 2: 120 Exceeded: 0 times Peak-1 Exceedance Level: 140 Exceeded: 0 times Peak-2 Exceedance Level: 140 Exceeded: 0 times Hysteresis: 2 Overloaded: 0 Pause Count: 0 Pause Time: 00:00:00.0 Calibrated: 12-Dec-2003 15:24:31 Offset: 8.8 dB Checked: 12-Dec-2003 15:24:31 Level: 91.9 dB Calibrator: LD 0504 Level: 114.0 Cal Record Count: 0 Interval Records: Enabled Number Interval Records: 1 Time History: Enabled Number History Records: 18 • Memory: Free Memory: Free 524288 290553 290553 Percent Free: 55.428 Battery Level: 71% Source: INT Sound Level Meter Summary Translated: 08-Mar-2004 14:15:02 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Document8\Projects\10579-01 Newport Beach GP\Noise Monitoring Data\Location 6.simdl Model Number: 814 Serial Number: A0114 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 6 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: criterion: Exchange Rate: Min: 45.9 Max: 70.5 Peak-1: 96.1 Peak-2: 83.3 (1.67) 67.7 (8.33) 61.7 (33.33) 56.8 (50.00) 55.4 (66.67) 54.1 (90.00) 52.1 18-Dec-2003 13:54:52 00:15:00.0 58.4 87.9 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 14:09:52 18-Dec-2063 13:56:33 18-Dec-2003 13:56:40 18-Dec-2003 14:06:42 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: 12-Dec-2003 Checked: 12-Dec-2003 Calibrator: LD 0504 Level: 114.0 Cal Record Count: 0 Interval Records: Enabled Time History: Enabled 814 Memory: 524288 Pree Memory: 290553 Battery Level: 71% Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 45.9 Max: 70.5 Peak-l: 96.1 Peak-2: 83.3 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times 18-Dec-2003 13:54:52 00:15:00.0 58.4 87.9 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 14:09:52 18-Dec-2003 13:56:33 18-Dec-2003 13:56:40 18-Dec-2003 14:06:42 Pause Time: 00:00:00.0 15:24:31 Offset: 8.8 dB 15:24:31 Level: 91.9 dB Number Interval Records: Number History Records: Percent Free: 55.42% Source: INT 1 18 • • • • • • Sound Level Meter Summary Translated: 08-Mar-2004 14:15:15 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Documents\Projects\10579-01 Newport Beach GP\Noise Monitoring Data\Location 7.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 7 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 45.1 Max: 67.5 Peak-1: 94.5 Peak-2: 84.2 (1.67) 64.8 (8.33) 61.7 (33.33) 58.1 (50.00) 56.6 (66.67) 55.0 (90.00) 50.5 18-Dec-2003 14:17:14 00:15:00.0 58.2 87.8 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 14:29:08 18-Dec-2003 14:30:12 18-Dec-2003 14:30:12 18-Dec-2003 14:24:17 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: Checked: Calibrator: Level: Cal Record Count: Interval Records: Time History: 814 Memory: Free Memory: Battery Level: Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 45.1 Max: 67.5 Peak-1: 94.5 Peak-2: 84.2 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times 18-Dec-2003 14:17:14 00:15:00.0 58.2 87.8 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 14:29:08 18-Dec-2003 14:30:12 18-Dec-2003 14:30:12 18-Dec-2003 14:24:17 Pause Time: 00:00:00.0 12-Dec-2003 15:24:31 Offset: 8.8 dB 12-Dec-2003 15:24:31 Level: 91.9 dB LD 0504 114.0 0 Enabled Number Interval Records: Enabled Number History Records: 524288 290553 Percent Free: 55.42% 70% Source: INT 1 18 Sound Level Meter Summary Translated: 08-Mar-2004 14:15:28 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Documents\Projects\10579-01 Newport Beach GP\Noise Monitoring Data\Location 8.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 8 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 45.2 Max: 78.8 Peak-1: 108.3 Peak-2: 92.7 (1.67) 72.1 (8.33) 64.6 (33.33) 58.7 (50.00) 56.4 (66.67) 53.4 (90.00) 48.6 18-Dec-2003 14:40:15 00:15:00.0 61.1 91.3 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 14:53:09 18-Dec-2003 14:53:42 18-Dec-2003 14:53:43 18-Dec-2003 14:53:42 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: 12-Dec-2003 Checked: 12-Dec-2003 Calibrator: LD 0504 Level: 114.0 Cal Record Count: 0 Interval Records: Enabled Time History: Enabled 814 Memory: 524288 Free Memory: 290553 Battery Level: 70% Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 45.2 Max: 78.8 Peak-l: 108.3 Peak-2: 92.7 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times 18-Dec-2003 14:40:15 00:15:00.0 61.7 91.3 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 14:53:09 18-Dec-2003 14:53:42 18-Dec-2003 14:53:43 18-Dec-2003 14:53:42 Pause Time: 00:00:00.0 15:24:31 Offset: 8.8 dB 15:24:31 Level: 91.9 dB Number Interval Records: Number History Records: Percent Free: 55.42% Source: INT 1 18 40 • • • Sound Level Meter Summary Translated: 08-Mar-2004 14:15:44 -------------------------------------------------------------------------------- File Translated: C:\Documents and Settings\MBrown.LAV-1\My Documents\Projects\10579-01 Newport Beach GP\Noise Monitoring Data\Location 9.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters! None Location: Newport Beach Location 9 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 48.0 Max: 77.4 Peak-1: 102.4 Peak-2: 97.2 L (1.67) 70.8 L (8.33) 66.9 L (33.33) 62.3 L (50.00) 59.8 L (66.67) 57.0 L (90.00) 52.6 18-Dec-2003 15:18:07 00:15:00.0 63.1 92.7 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 15:18:37 18-Dec-2003 15:26:33 18-Dec-2003 15:26:32 18-Dec-2003 15:19:50 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: Checked: Calibrator: Level: Cal Record Count: Interval Records: Time History: 12-Dec-2003 15:24:31 12-Dec-2003 15:24:31 LD 0504 114.0 0 Enabled Enabled • 814 Memory: 524288 Free Memory: 290553 Battery Level: 70% Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 48.0 Max: 77.4 Peak-1: 102.4 Peak-2: 97.2 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times 18-Dec-2003 15:18:07 00:15:00.0 63.1 92.7 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 15:18:37 18-Dec-2003 15:26:33 18-Dec-2003 15:26:32 18-Dec-2003 15:19:50 Pause Time: 00:00:00.0 Offset: 8.8 dB Level: 91.9 dB Number Interval Records: Number History Records: Percent Free: 55.42% Source: INT 1 18 Sound Level Meter Summary Translated: 08-Mar-2004 14:15:58 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Newport Beach GP\Noise Monitoring Data\Location 10.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 1514inute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 10 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 50.3 Max: 18.7 Peak-1: 97,4 Peak-2: 96.8 (1.67) 67.2 (8.33) 64_4 (33.33) 59.5 (50.00) 57.6 (66.67) 56.0 (90.00) 53.7 18-Dec-2003 15:39:06 00:15:00.0 60.5 90.1 0.00 Q.00 0 dB 0 dB 3 dB 18-Dec-2903 15:49:50 18-Dec-2003 15:44:49 18-Dec-2003 15:44:48 18-Dec-2003 15:44:48 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: 12-Dec-2003 Checked: 12-Dec-2003 Calibrator: LD 0504 Level: 114.0 Cal Record Count: 0 Interval Records: Enabled Time History: Enabled 814 Memory: 524288 Free Memory: 290553 Battery Level: 69% Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose; Threshold: criterion: Exchange Rate: Min: 50.3 Max: 78.7 Peak-1: 97.4 Peak-2: 96.8 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Documents\Projects\30579-01 18-Dec-2003 15:39:06 00:15:00.0 60.5 90.1 0.00 0.00 0 dB 0 dB 3 dB 18-Dec-2003 15:49:50 18-Dec-2003 15:44:49 18-Dec-2003 15:44:48 18-Dec-2003 15:44:48 Pause Time: 00:00:00.0 15:24:31 Offset: 8.8 dB 15:24:31 Level: 91.9 dB Number Interval Records: Number History Records: Percent Free: 55.42% Source: INT 1 18 0 • • • Cl Sound Level Meter Summary Translated: 08-Mar-2004 14:16:09 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Newport Beach GP\Noise Monitoring Data\Location ll.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 11 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 42.4 Max: 69.9 Peak-1: 96.0 Peak-2: 93.8 19-Dec-2003 11:22:04 00:15:00.0 59.4 88.9 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 11:29:33 19-Dec-2003 11:27:46 19-Dec-2003 11:22:56 19-Dec-2003 11:22:56 Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 42.4 Max: 69.9 Peak-1: 96.0 Peak-2: 93.8 Documents\Projects\10579-01 19-Dec-2003 11:22:04 00:15:00.0 59.4 88.9 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 11:29:33 19-Dec-2003 11:27:46 19-Dec-2003 11:22:56 19-Dec-2003 11:22:56 L (1.67) 67.4 L (8.33) 64.4 L (33.33) 58.6 L (50.00) 54.2 L (66.67) 49.7 L (90.00) 43.0 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 Exceeded: 0 times SPL Exceedance Level 2: 120 Exceeded: 0 times Peak-1 Exceedance Level: 140 Exceeded: 0 times Peak-2 Exceedance Level: 140 Exceeded: 0 times Hysteresis: 2 Overloaded: 0 Pause Count: 0 Pause Time: 00:00:00.0 Calibrated: Checked: Calibrator: Level: Cal Record Count: 12-Dec-2003 15:24:31 12-Dec-2003 15:24:31 LD 0504 114.0 0 Offset: 8.8 dB Level: 91.9 dB Interval Records: Enabled Number Interval Records: 1 Time History: Enabled Number History Records: 18 814 Memory: Free Memory: Battery Level: 524288 290553 68% Percent Free: 55.42% Source: INT Sound Level Meter Summary Translated: 08-Mar-2004 14:16:23 File Translated: C:\Documents and Settings\MBrown.1AV-1\My Newport Beach GP\Noise Monitoring Data\Location 12.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name. E1P Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup ➢escr: 15 Minute Octave Filters: None Location: Newport Beach Location 12 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 50.0 Max: 75.6 Peak-1: 97.6 Peak-2: 91.7 L (1.67) 66.8 L (8.33) 63.7 L (33.33) 60.2 L (50.00) 58.3 L (66,67) 56.4 L (90.00) 53.4 19-Dec-2003 11:52:00 00:15:00.0 60.5 90.1 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 11:58:43 19-Dec-2003 11:55:39 19-Dec-2003 11:55:39 19-Dec-2003 11:53:35 Detector: Slow Weighting: A Ohs Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: Checked: Calibrator: Level: Cal Record Count: Interval Records: Time History: 814 Memory: Free Memory: Battery Level: Start Time Elapsed Time Leg: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 50.0 Max: 75.6 Peak-1: 97.6 Peak-2: 91.7 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Documents\Projects\10579-01 19-Dec-2003 11:52:00 00:15:00.0 60.5 90.1 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 11:58:45 19-Dec-2003 11:55:39 19-Dec-2003 11:55:39 19-Dec-2003 11:53:35 Pause Time: OOe00:00.0 12-Dec-2003 15:24:31 Offset: 8.8 dB 12-Dec-2003 15:24:31 Level: 91.9 dB LD 0504 114.0 0 Enabled Number Interval Records: Enabled Number History Records: 524288 290553 Percent Free: 55.42% 69% Source: INT 1 18 6 • 11 • Sound Level Meter Summary Translated: 08-Mar-2004 14:16:36 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Documents\Projects\10579-01 Newport Beach GP\Noise Monitoring Data\Location 13.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 13 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 43.0 Max: 72.4 Peak-1: 94.5 Peak-2: 87.0 (1.67) 64.6 (8.33) 59.3 (33.33) 54.5 (50.00) 52.8 (66.67) 51.3 (90.00) 48.3 19-Dec-2003 12:24:05 00:15:00.0 56.0 85.6 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 12:37:35 19-Dec-2003 12:25:33 19-Dec-2003 12:33:55 19-Dec-2003 12:24:12 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: SPL Exceedance Level 2: Peak-1 Exceedance Level: Peak-2 Exceedance Level: Hysteresis: Overloaded: Pause Count: Calibrated: Checked: Calibrator: Level: Cal Record Count: Interval Records: Time History: Start Time Elapsed Time Leg: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 43.0 Max: 72.4 Peak-1: 94.5 Peak-2: 87.0 19-Dec-2003 12:24:05 00:15:00.0 56.0 85.6 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 12:37:35 19-Dec-2003 12:25:33 19-Dec-2003 12:33:55 19-Dec-2003 12:24:12 115.00 Exceeded: 0 times 120 Exceeded: 0 times 140 Exceeded: 0 times 140 Exceeded: 0 times 2 0 0 Pause Time: 00:00:00.0 12-Dec-2003 12-Dec-2003 LD 0504 114.0 0 Enabled Enabled • Free Memory: 524288 290553 Free Memory: 290553 Battery Level: 67% 15:24:31 Offset: 8.8 dB 15:24:31 Level: 91.9 dB Number Interval Records: 1 Number History Records: 18 Percent Free: 55.42% Source: INT Sound Level Meter Summary Translated: 08-Mar-2004 14:17:03 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Documents\Projects\10579-01 Newport Beach GP\Noise Monitoring Data\Location 14.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 14 Note 1: Note 2: Overall Measurement Current Measurement --------------------------------------- Start Time: 19-Dec-2003 12:55:06 --------------------------------------- Start Time 19-Dec-2003 12:55:06 Elapsed Time: 00:15:00.0 Elapsed Time 00:15:00.0 Leq: 61.8 Leg: 61.8 SEL: 91.4 SEL: 91.4 Dose: 0.00 Dose: 0.00 Proj. Dose: 0.00 Proj. Dose: 0.00 Threshold: 0 dB Threshold: 0 dB Criterion: 0 dB Criterion: 0 dB Exchange Rate: 3 dB Exchange Rate: 3 dB Min: 47.0 19-Dec-2003 13:05:09 Min: 47.0 19-Dec-2003 13:05:09 Max: 81.1 19-Dec-2003 13:03:05 Max: 81.1 19-Dec-2003 13:03:05 Peak-1: 99.7 19-Dec-2003 18:03:05 Peak-1: 99.7 19-Dec-2003 13:03:05 • Peak-2: 94.1 19-Dec-2003 13:03:04 Peak-2: 94.1 19-Dec-2003 13:03:04 L (1.67) 70.1 L (8.33) 65.3 L (33.33) 58.5 L (50.00) 55.1 L (66.67) 53.0 L (90.00) 50.1 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115f00 Exceeded: 0 times SPL Exceedance Level 2: 120 Exceeded: 0 times Peak-1 Exceedance Level: 140 Exceeded: 0 times Peak-2 Exceedance Level: 140 Exceeded: 0 times Hysteresis: 2 Overloaded: 0 Pause Count: 0 Pause Time: 00:00:00.0 calibrated: 12-Dec-2003 15:24:31 Offset: 8.8 dB Checked: 12-Dec-2003 15:24:31 Level: 91.9 dB Calibrator: LD 0504 Level: 114.0 Cal Record Count: 0 Interval Records: Enabled Number Interval Records: 1 Time History: Enabled Number History Records: 18 Memory: 524288 Free Free Memory: 290553 290553 Percent Free: 55.928 • Battery Level: 67% Source: INT • • E Sound Level Meter Summary Translated: 08-Mar-2004 14:17:22 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Newport Beach GP\Noise Monitoring Data\Location 15.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 15 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leg: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 33.4 Max: 53.8 Peak-1: 91.3 Peak-2: 79.8 (1.67) 47.3 (8.33) 44.0 (33.33) 39.2 (50.00) 37.8 (66.67) 36.8 (90.00) 35.3 19-Dec-2003 13:20:46 00:15:00.0 40.2 69.7 4256.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 13:27:59 19-Dec-2003 13:34:37 19-Dec-2003 13:29:09 19-Dec-2003 13:25:42 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: 12-Dec-2003 Checked: 12-Dec-2003 Calibrator: LD 0504 Level: 114.0 Cal Record Count: 0 Interval Records: Enabled Time History: Enabled 814 Memory: 524288 Free Memory: 290553 Battery Level: 66% Start Time Elapsed Time Leg: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 33.4 Max: 53.8 Peak-1: 91.3 Peak-2: 79.8 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Documents\Projects\10579-01 19-Dec-2003 13:20:46 00:15:00.0 40.2 69.7 4256.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 13:27:59 19-Dec-2003 13:34:37 19-Dec-2003 13:29:09 19-Dec-2003 13:25:42 Pause Time: 00:00:00.0 15:24:31 Offset: 8.8 dB 15:24:31 Level: 91.9 dB Number Interval Records: Number History Records: Percent Free: 55.42% Source: INT 1 18 Sound Level Meter Summary Translated: 08-Mar-2004 14:17:39 Pile Translated: 'C:\Documents and Settings\MBrown.LAV-1\My Newport Beach GP\Noise Monitoring Data\Location 16.simdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: I$Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 16 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: criterion: Exchange Rate: Min: 41.8 Max: 82.3 Peak-1: 101.4 Peak-2: 96.0 (1.67) 74.0 (8.33) 69.7 (33.33) 65.1 (50.00) 62.8 (66.67) 59.6 (90.00) 53.7 19-Dec-2003 13:45:36 00:25:00.0 66.0 95.6 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 13:54:45 19-Dec-2003 13:51:21 19-Dec-2003 13:51:21 19-Dec-2003 13:51:21 Detector: glow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count! 0 Calibrated: 12-Dec-2003 Checked: 12-Dec-2003 Calibrator: LD 0504 Level: 114.0 Cal Record Count: 0 Interval Records: Enabled Time History: Enabled 814 Memory: 524288 Free Memory: 290553 Battery Level: 67% Start Time Elapsed Time Lpq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 41.8 Max: 82.3 Peak-1: 101.4 Peak-2: 96.0 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Documents\Project6\10579-01 19-Dec-2003 13:45:36 00:15:00.0 66.0 95.6 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 13:54:45 19-Dec-2003 23:51:21 19-Dec-2003 13:51:21 19-Dec-2003 13:51:21 Pause Time: 00:00:00.0 15:24:31 Offset: 8.8 dB 15:24:31 Level: 91.9 dB Number Interval Records: Number History Records: Percent Free: 55.42% Source: INT 1 18 40 • 4 • • Sound Level Meter Summary Translated: 08-Mar-2004 14:17:51 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Documents\Projects\10579-01 Newport Beach GP\Noise Monitoring Data\Location 17.slmd1 Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 17 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 47.2 Max: 85.2 Peak-1: 108.4 Peak-2: 96.3 (1.67) 73.8 (8.33) 69.1 (33.33) 63.6 (50.00) 61.5 (66.67) 58.6 (90.00) 54.2 19-Dec-2003 14:09:55 00:15:00.0 66.1 95.7 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 14:19:12 19-Dec-2003 14:11:33 19-Dec-2003 14:19:44 19-Dec-2003 14:11:32 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: 12-Dec-2003 Checked: 12-Dec-2003 Calibrator: LD 0504 Level: 114.0 Cal Record Count: 0 Interval Records: Enabled Time History: Enabled 814 Memory: 524288 Free Memory: 290553 Battery Level: 66% Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 47.2 Max: 85.2 Peak-1: 108.4 Peak-2: 96.3 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times 19-Dec-2003 14:09:55 00:15:00.0 66.1 95.7 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 14:19:12 19-Dec-2003 14:11:33 19-Dec-2003 14:19:44 19-Dec-2003 14:11:32 Pause Time: 00:00:00.0 15:24:31 Offset: 8.8 dB 15:24:31 Level: 91.9 dB Number Interval Records: Number History Records: Percent Free: 55.42% Source: INT 1 18 Sound Level Meter Summary Translated: 08-Mar-2004 14:18:06 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Newport Beach GP\Noise Monitoring Data\Location 18.s1mdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: LCs Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 18 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 53.2 Max: 75.1 Peak-1: 101.3 Peak-2: 94.3 (1.67) 70.7 (8.33) 67.5 (33.33) 65.2 (50.06) 63.9 (66.67) 62.6 (90.00) 59.4 19-Dec-2003 14:37:01 00:15:00.0 64.9 94.4 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 14:41:ll 19-Dec-2003 14:41:58 19-Dec-2003 14:39:02 19-Dec-2003 14:47:20 Detector: slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: Checked: Calibrator: Level: Cal Record Count: Interval Records: Time History: 12-Dec-2003 15:24:31 1$-Dec-2003 15:24:31 LD 0504 114.0 0 Enabled Enabled Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 53.2 Max: 75.1 Peak-1: 101.3 Peak-2: 94.3 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Documents\Projects\10579-01 19-Dec-2003 14:37:01 00:15:00.0 64.9 94.4 0.00 0.00 0 dS 0 dB 3 dB 19-Dec-2003 14:41:11 19-Dec-2003 14:41:58 19-Dec-2003 14:39:02 19-Dec-2003 14:47:20 Pause Time: 00:00:00.0 Offset: 8.8 dB Level: 91.9 dB Number Interval Records: Number History Records: 814 Memory: 524288 Free Memory: 290553 Percent Free: 55.42% Battery Level: 66% Source: INT 1 18 E 11 • • • Sound Level Meter Summary Translated: 08-Mar-2004 14:18:21 File Translated: C:\Documents and Settings\MBrown Newport Beach GP\Noise Monitoring Data\Location 19 Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None LAV-1\My Documents\Projects\10579-01 slmdl Location: Newport Beach Location 19 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 47.0 Max: 73.0 Peak-1: 100.1 Peak-2: 86.7 L (1.67) 70.0 L (8.33) 66.5 L (33.33) 62.5 L (50.00) 61.0 L (66.67) 59.7 L (90.00) 55.2 19-Dec-2003 15:01:04 00:15:00.0 62.8 92.4 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 15:08:21 19-Dec-2003 15:05:40 19-Dec-2003 15:15:07 19-Dec-2003 15:05:39 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: Checked: Calibrator: Level: Cal Record Count: Interval Records: Time History: 12-Dec-2003 15:24:31 12-Dec-2003 15:24:31 LD 0504 114.0 0 Enabled Enabled • Free Memory: 524288 290553 Free Memory: 290553 Battery Level: 65% Start Time Elapsed Time Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 47.0 Max: 73.0 Peak-1: 100.1 Peak-2: 86.7 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times 19-Dec-2003 15:01:04 00:15:00.0 62.8 92.4 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 15:08:21 19-Dec-2003 15:05:40 19-Dec-2003 15:15:07 19-Dec-2003 15:05:39 Pause Time: 00:00:00.0 Offset: 8.8 dB Level: 91.9 dB Number Interval Records: Number History Records: Percent Free: 55.42% Source: INT 1 18 Sound Level Meter Summary Translated: 08-Mar-2004 14:12:08 File Translated: C:\Documents and Settings\MBrown.LAV-1\My Newport Beach GP\Noise Monitoring Data\Location 20.slmdl Model Number: 814 Serial Number: A0174 Firmware Rev: 1.026 Software Version: 1.070 Name: EIP Associates Descrl: 12301 Wilshire Blvd. Suite 430 Descr2: Los Angeles, CA 90025 Setup: 15Minute.slm Setup Descr: 15 Minute Octave Filters: None Location: Newport Beach Location 20 Note 1: Note 2: Overall Measurement Current Measurement Start Time: Elapsed Time: Leq: SEL: Dose: Proj. Dose: Threshold: Criterion: Exchange Rate: Min: 50.4 Max: 78.9 Peak-1: 102.5 Peak-2: 95.5 (1.67) 72.3 (8.33) 66.6 (33.33) 61.4 (50.00) 59.5 (66.67) 57.8 (90.00) 54.8 19-Dec-2003 15:31:26 00:15:00.0 63.3 92.8 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 15:44:09 19-Dec-2003 15:34:15 19-Dec-2003 15:34:15 19-Dec-2003 15:42:54 Detector: Slow Weighting: A Oba Filter: 1000 Hz SPL Exceedance Level 1: 115.00 SPL Exceedance Level 2: 120 Peak-1 Exceedance Level: 140 Peak-2 Exceedance Level: 140 Hysteresis: 2 Overloaded: 0 Pause Count: 0 Calibrated: Checked: Calibrator: Level: Cal Record Count: Interval Records: Time History: 12-Dec-2003 15:24:31 12-Dec-2003 15:24:31 LD 0504 114.0 0 Enabled Enabled Start Time Elapsed Time Leq: SEL: Dose: PLOj. Dose: Threshold: Criterion: Exchange Rate: Min: 50.4 Max: 78.9 Peak-l: 102.5 Peak-2: 95.5 Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Exceeded: 0 times Documents\Projects\30579-01 19-Dec-2003 15:31:26 00:15:00.0 63.3 92.8 0.00 0.00 0 dB 0 dB 3 dB 19-Dec-2003 15:44:09 19-Dec-2003 15:34:15 19-Dec-2003 15:34:15 19-Dec-2003 15:42:54 Pause Time: 00:00:00.0 Offset: 8.8 dB Level: 91.9 dB Number Interval Records: Number History Records: 814 Memory: 524288 Free Memory: 290553 Percent Free: 55.42% Battery Level: 60 Source: TNT 1 18 • TRAFFIC NOISE LEVELS AND NOISE CONTOURS • Project Number. 10579.01 Project Name: Newport Beach General Plan Update I• Background Information Model Description: FHWA Highway Noise Prediction Model (FHWA-RD-77-108) with California Vehicle Noise (CALVENO) Emission Lewis. SourceofTMgc Volumes: Meyer, Mohaddes&Associates Community Noise Descriptor. La,,: CNEL• X Assumed 24-HourTremc Distribution: Day Evening Night TotalADTVolumes 77.70% 12.70% 0.60% Medium -Duty Trucks 87.43% 5.05% 7.62% Heavy -Duty Tmcks 89.10% 2.84% 8.06% Design Vehicle Mix Distance from Centedlne of Roadways Analysis Condition Medlan ADT Speed Alpha Medium Heavy CNELat Distance to Contour Roadway Segment Lanes Width Volume (mph) Factor Trucks Trucks 100 Feet 70 CNEL 65 CNEL 60 CNEL Existing Traffic Volumes 18th Street Irvine Avenue to Dover Drive 2 12 5,001) 35 0.5 1.8% 0.7% 55.7 - - 52 32nd street weal of Newport Boulevard 2 12 8,000 35 0.6 1.8% 0.7% 57.7 - - 71 east of Newport Boulevard 2 12 3,00D 35 0.6 1.8% 0.7% 53.6 - - - Avacado Avenue north of San Miguel Drive 2 12 5,00D 30 0.5 1.8% 0.7% 54.6 - - 44 south of Son Miguel Drive 4 12 12.000 45 0.5 1.8% 0.7% 02.2 - 65 140 north of Coast Highway 4 12 11,000 45 0.5 1.8% 0.7% 61.8 - 61 132 Balboa Boulevard south of Coast Highway 4 0 18,000 30 0.5 1.6% 0.7% 60.3 - 48 104 Baysids Drive south of Coast Highway 4 12 10,000 30 0.6 1.8% 0.7% 67.8 - - 71 Birch Street Jamboree Road to Von Kerman Avenue 4 12 12,000 40 0.6 1.8% 0.7% 61.0 - 64 118 Von Kerman Avenue to MacArthur Boulavan 4 12 15,000 40 0.6 1.8% 0.7% 61.9 - 63 135 west of MacArthur Boulevard 4 12 16,000 40 0.6 1.8% 0.7% 62.2 - 65 141 north of Bristol Street North 4 12 23,000 40 0.5 1.8% 0.7% 63.8 - 83 179 Bristol Street North to Bristol Street South 4 12 19,000 40 0.6 1.8% 0.7% 63.0 - 73' 168 south of Bristol Street South 4 12 16,000 40 0.5 1.8% 0.7% 61.9 - 63 135 Olson Avenue Jamboree Road to MacArthur Boulevard 6 12 13,000 40 0.6 1.8% 0.7% 61.6 - - 128 MacArthur Boulevard to SR-73 Freeway a 12 7,001) 40 0.5 1.6% 0.7% 68.0 - - 84 Bonita Canyon Dr. east of MacArthur Boulevard 4 12 26,0D0 50 0.5 1.8% 0.7% 66.7 60 130 279 west of SR-73 Freeway 4 12 17,000 50 0.6 1.8% 0.7% 64.8 - 98 210 Bristol Street North west of Campus Drive 4 0 28.000 40 0.5 1.8% 0.7% 64.6 - 94 202 Campus Drive to Birch Street 4 0 23,000 40 0.6 1.8% 0.7% 63.7 - 82 177 east of Birch Street 4 0 22.000 40 0.5 1.8% 0.7% 63.5 - 8D 172 west of Jamboree Road 4 0 18.000 40 0.5 1.8% 0.7% 62.1 - 84 139 west of Campus DrivallrAns Drive 4 0 28,000 40 0.5 1.8% 0.7°% 64.6 - 94 202 Newport Existing Noise Comours.xia EIP Associates 319/2004 Newport Boulevard to Riverside Avenue 8 12 63,000 65 0.6 1.8% 0.7% 71.1 118 264 648 Riverside Avenue to Tustin Avenue 6 12 46,000 65 0fi 1.8% 0.7% 70.2 103 223 400 Tustin Avenue to Dover Drive 6 12 42,000 65 0.5 1.8% 0.7% 00.9 g9 213 469 . Dover Drive to Boyslde Drive 4 12 63,000 65 0.6 1.6% 0.7% 71.6 127 274 601 Sayalds Drive to Jamboree Road 7 12 61,000 65 0.5 1.6% 0.7% 71.1 118 256 549 Jamboree Road to Newport Center Drive 8 12 42,000 56 0.6 1.6% 0.7% 70.6 107 232 499 Newport Center Drive to Avocadopvenue B 12 36,000 65 0.6 1.8% 0.7% 69.3 89 103 415 Avocado Avenue to MacArthur Boulevard 6 12 3O.ODO 55 0.6 1.8% 0.795 ODA of 196 423 MacArthur Boulevard to Goldenrod Avenue 4 12 40.000 55 0.6 1.8% 0.7% 69.6 04 203 438 Goldenrod Avenue to MargueraeAvenue 2 0 30.ODO 65 0.6 1.8% 0.7% 69.3 90 194 417 MarguadleAvenue to Poppy Avenue 4 12 35,000 66 0.6 1.6% 0.7% 69.0 a8 lea 399 PoppyAvenue to Newport Coast Drive 6 12 28,0DO 65 0.5 1.8% 0.7% 65.3 77 18B 355 east of Newport Coast Drive 6 12 35,0DO 66 0.6 1.8% 0,7% 69.3 89 103 476 Dovar Drive IMne Drive to Westoo f Drive 2 0 9,001) 30 0.5 1.8% 0.71% 67.1 - - 65 Westdgf Drive to 16th Street 2 0 22,000 4D 0.6 1.8% 0.7% 63.4 38 70 169 16th Slreetto C69Ddve 2 0 25,000 40 0.6 1.B% 0.7% 64.0 40 86 184 CIIO Drive to Coast Highway 2 0 29,ODO 4D 0.6 1.8% 0.7% 64.6 44 94 204 Eastbluff Drive west of Jamboree Road at Unlve" Drive 4 12 10.OD0 45 0.6 1.8% 0.7% 81.4 - 68 124 west of Jamboree Road at Ford Road 5 12 16,001) 45 0.5 1.6% 0.7% 63.3 - 77 lea Ford Road Jamboree Road to MacArthur Boulevard 4 12 9,000 45 0.5 118% 0.7% 01.0 - 64 118 Goldenrod Avenue north of Coast Highway 2 0 ZOOS 45 0.5 1.6% 0.7% 54.2 - 41 Highland Drive east of lrvine Avenue 2 0 ZOOS 45 0.6 1.8% 0.7% 64.2 41 Hospbl Road Placentia Avenue to Newport Soulavard 4 12 13,000 35 0.5 1.895 0.7% 60.0 - 100 east of Newport Boulevard 4 12 7,000 35 0.6 1.8% 0.7% 67.3 - 66 Irvin Avenue Bristol Street South to Mew Drive 4 12 27,000 35 0.6 1.8% 0.7% 63.2 - 75 162 Mesa Drive to University Drive 4 12 31,000 35 0.6 1.8% 0.7% 63.8 83 178 University Drive to Santa Isabel Avenue 4 12 33,000 35 0.6 1.8% 0.7% 04.0 - 88 lea Santa Isabel Avenue to Santiago Drive Santiago Drive to Highland Drive 4 4 12 12 29,000 27,000 35 36 0.6 0.5 1.8% 1.8% 0.7% 0.7% 03.5 63.2 79 76 170 162 Highland Drive to Dover Drive 4 12 27,ODO 35 0.6 1.$% 0.7% 63.2 - 75 162 ., Dover Drive to Wwtcliq Drive 4 12 22.000 35 0.5 118% 0.7% 82.3 88 142 Weslellff Drive to lath Street 4 12 12.000 36 0.6 1.8% 0.7% 69.0 96 Jamborees Road Campus Drive to Birch Street 6 12 38,000 65 0.6 1.8% 0.7% ODA tit 190 423 ,Birch Street to MacArthur Boulevard 6 12 42,000 65 0.6 1,8% 0.7% 70.1 101 218 469 MacArthur Boulevard to Bristol street Noah 6 12 30,000 65 0.6 1.8% 0.7% 09.4 81 186 423 Bristol Street North to Bristol Street South 6 12 47,000 86 0.6 1.6% 0.7% 70.6 10D 235 Soo Bristol Street South to Bayvlew Way 6 12 47,000 65 0.5 1.8% 0.7% 70.6 10D 235 506 Bayvtew Way to University Drive 8 12 47,000 55 0.6 1.6% 0.7% 70.6 10D 235 508 University Drive to Bison Avenue 8 12 37,000 55 0.6 1.6% 0.7% 69.5 93 200 431 Bison Avenue to Ford Road 6 12 39,000 65 0.6 1.8% 0.7% 69.7 g8 207 446 Ford Road to San Joaquin Hills Road B 12 48,000 55 0.6 1.8% 0.7% 70.6 107 231 498 San Joaquin Hills Rod to Santa Barbara Dr 6 12 34,000 65 0.6 1.8% 0.7% 89.2 88 189 407 Santa Barbara Drive to Coast Highway 6 12 32.000 55 0.5 1_8% 0.7% Bale 84 182 301 Coast Highway to Bayside Drive 4 12 12,OOD 55 0.6 1.8% 0.7% 64.4 91 198 MacArthur Boulevard Campus Drive to Birch Street 6 12 27,ODO 55 0.5 1.8% 0.7% Sall 76 162 349 Birch Street to Von KennanAvanue 8 12 22,OD0 55 0.5 1.8% 0.7% 67.3 68 141 305 Von Karman Avenue to Jamboree Rod 8 12 28,OD0 55 0.5 1.$% 0.7% 68.0 73 168 341 • Newport Usling Noise Conloun.Ws EIP Assoolalas 3I02004 i r r le Coast Coast Highway to Via Lido 6 12 48,000 30 0.5 1.8% 0.7% 64.9 - 98 211 Via Lido to 32nd Street 6 12 36,000 30 0.6 1.8% 0.7% 63.6 - 81 174 south of 32nd Street 6 12 29,ODO 30 0.5 1.8% 0.7% 62.7 - 70 161 Newport Center Drive north of Coast Highway 6 12 14.000 45 0.5 1.8% 0.7% 63.1 - 75 162 , Newport Coast Drive SR-73 Freeway to San Joaquin Hills Road 4 12 17,000 40 0.5 1.8% 0.7% 62.6 - 68 147 south of Son Joaquin Hills Road 6 12 15,000 40 0.5 1.8% 0.7% 62.2 - 65 140 north of Coast Highway 6 12 12.000 40 0.5 1.8% 0.7% 61.2 - - 121 Placentia Avenue north of SupedorAvenue 4 12 12,000 40 06 1.8°% 0.7% 61.0 - 64 116 SuperiorAvenueto Hospital Road 4 12 7,000 40 0.5 1.8% 0.7% 58.6 - - 61 Poppy Avenue north of Coast Highway 2 0 2,0011 40 0.5 1.8% 0.7% 53.0 - - 34 Riverside Avenue north of Coast Highway 2 0 9.000 30 0.5 1.8% 0.7% 57.1 - - 65 San Joaquin Hills Road Jamboree Road to Santa Cruz Road 6 12 18,000 45 0.5 1.8% 0.7% 63.7 - 82 177 Santa Cruz Road to Santa Rosa Road 6 12 11,001) 45 0.5 1.8% 0.7% 62.1 - 64 138 Santa Roes Road to MacArthur Boulevard 6 12 21,000 45 0.6 1.8% 0.7% 64.9 - 98 212 MacArthur Boulevard to San Miguel Road 5 12 19,000 45 0.5 1.8% 0.7% 64.3 - 90 194 San Miguel Road to Marguerite Avenue 6 12 18,000 45 0.6 1.8% 0.7% 64.2 - 89 191 Marguerite Avenue to Spyglass HIII Road 6 12 12,000 45 0.5 1.8% 0.7% 62.6 - 68 146 Spyglass HIII Road to Newport Coast Drive 4 12 12,000 45 0.5 1.8% 0.7% 62.2 - 65 140 San Miguel Drive north of Spyglass HIII Road 4 12 7,000 40 0.5 1.8% 0.7% 58.6 - - 81 south of Spyglass HIII Road 4 12 7,000 40 0.6 1.8% 0.7% 68.6 - - 81 north of San Joaquin Hills Road 4 12 12,000 40 0.6 1.8% 0.7% 61.0 - 54 118 San Joaquin Hills Road to MacArthur Boulav 4 12 12,00D 45 0.5 1.8% 0.7% 62.2 - 65 140 MacArthur Boulevard to Avocado Avenue 4 12 19,000 45 0.6 1.8% 0.7% 64.2 - 88 191 west of Avocado Avenue 4 12 10.000 45 0.5 1.8% 0.7% 61.4 - 58 124 Santa Barbara Drive east of Jamboree Road 4 12 10,000 40 0.6 1.8% 0.7% 6D.2 - - 103 Santa Cruz Drive south of San Joaquin Hills Road 4 12 8,000 40 0.5 1.8% 0.7% 69.2 - - 89 Santa Rosa Drive south of San Joaquin Hills Road 4 12 11,000 40 0.5 1.8% 0.7% 60.6 - 51 110 Santiago Drive Tustin Avenue to Irvine Avenue 2 12 6,000 45 0.6 1.8% 0.7% $8.3 - 77 east of Irvine Avenue 2 12 3,000 45 0.5 1.8% 0.7% 66.0 - - 64 Spyglass HIII Road San Miguel Drive to Son Joaquin Hills Road 2 12 4,000 40 0.6 1.8% 0.7% 66.1 - - 55 Superior Avenue north of Placentia Avenue 4 12 17,000 40 0.6 1.8% 0.7% 62.5 - 68 147 PlacentlaAvenue to Hospital Road 4 12 22.000 40 0.5 1.8% 0.7% 63.6 - 81 174 Hospital Road to Coast Highway 4 12 24.000 40 0.5 1.8% 0.7% 64.0 - 86 184 Tustin Avenue north of Coast Highway 2 0 2,000 40 0.5 1.8% 0.7% 53.0 - - 34 University Drive east of Irvine Avenue 4 12 3.000 55 0.5 1.8% 0.7% 58.3 - - 78 east of Jamboree Road 4 12 11,000 55 0.6 1.8% 0.7% 64.0 - a6 185 Via Lido east of Newport Boulevard 4 12 8,001) 35 0.6 1.8% 0.7% 57.9 - - 72 Von Kaman Avenue Campus Drive to Birch Street 4 12 14,000 40 0.6 1.8% 0.7% 61.6 - 60 129 Birch Street to MacArthur Boulevard 4 12 12.000 40 0.5 1.8% 0.7% 61.0 - 64 116 Westcliff Drive Irvine Avenue to Dover Drive 4 12 16,000 35 0.5 1.8% 0.7% 60.9 - 53 116 r Distance is from the eenledlns of the roadway segment to the receptor location. = - contour is located within the roadway right-of-way. Newport Existing Noise Conlou s.xls EIP Associates 31912004