The URL can be used to link to this page

Home My WebLink AboutSS3 - Newport Bay Flood Levels - PowerPointiTi i ►� : - , • • i 40 A Presentation on Newport Harbor's Base Flood Elevation (BFE) Balboa Island Sea Wall Height �I 0 s, �resentatic Changes to the National Flood Insurance Program. Biggert- Waters Flood Insurance Reform Act of 2012 Results of the Base Flood Elevation Study by DHI. Balboa Island - Sea Wall Replacement. Hurricane Season in 2005 - Katrina, Rita, Wilma cost the nation $17.713illion. Then came Sandy in 2012. Government paid out more $ in claims than premiums received. Additional financial burden to Taxpayers. Biggert - Waters Flood Insurance Reform Act of 2012 ,x Rates are going to reflect current RISK. ❖ The Higher the Risk the Higher the Premium. Same concept as auto insurance. Risk will be based on whether the property is above or below the Base Flood (BFE). Elevation Establishing the height of the BFE and the height of the property in reference to the BFE is critical. Current Base Flood Elevation is 9.0'. Rate comparisons $2.23&yr $2.235/yr Non-Actuarial $2.23&yr I fool above BFE toot below 8F E feet below BFE $OIWYr $5,6231yr Actuarial $25,000,ayr Lj 84Ading- $200,000 Contents- $80,000(2201224 Ratesi J I�F.tii � iZ1iT1MAffrel" - 1ira: M40 M single -story structure: Subsidized Premium Rates before Premium Rates following elimination of BW12 subsidies— after October 1, 2013 Pre -BW 12 Subsidized Rates for Post -BW12 non- subsidzed Rates for $250K /$100K Building /Contents Policy $250K/$100K Building /Contents Policy in in high risk, non - coastal AE zones (no high -risk non - coastal AE zones (with elevation certificate) . Elevation Certificate). Lowest floor of property is 4 feet $3,600 $553 above base flood elevation Lowest floor of property is at $3,600 $1,815 base flood elevation Lowest floor of property is 4 $3,600 $10,723 feet below base flood elevation Insurance will increase at a rate of 25% per year until at adjusted rate. Non - primary residence Owners of businesses Change of Ownership / New Loan New Policy Insurance Lapse deduce Insurance Cc How do you Address your Risk? Know your property elevation compared to BFE. -You may need to hire a surveyor. Speak to your Insurance Agent. www.newportbeachca.gov Search: surveyors elevation y �� ` ` ` 1' - I ■III IIII i IIII II 11' II11 1111_1 � -, * =�� -�� • `� � � .`4Q III 11111 II III 111 _ �� C_ _� �_ == ��i�� ®,� ��I_' IIIIIIII 11■ 1111■ 111.1. 111 1 1111 1111 1111 111111 1111 111 1 111 _ 1 1 \, _ _ y L KIN •:• • 7 Unit 19M - 7 Unit IM - 12 Unit 12 Unft 11 Unit Parcels vAlh EC's - 269 Total or 19% INI Unt; 9WAUnts M1 - 6 Unit � - 13 Unfts Mll - 8 Unit Parcels wthout ECS - 1,148 Total or 81% 7� deduce Insurance Cc HOW DO YOU REDUCE INSURANCE RATES? Elevate the building; Discuss mitigation measures with your Agent; Increase the deductible; More information can be found at: www.fema.gov 1bw12 Current Congressional Spending bill & future bills. May delay rate increase for some property owners. Base Flood Elevation Study :1�: j.�a r@lGl• ■ ra�f: j j [Gj fi ■ ■: Study (public copy provided)conducted by DHI w/ help from Lyle Engineering: To Determine if FEMA's BFE of 9.0' is correct? To Determine BFE based on recent data? Minimum Seawall height so Balboa Island is no longer in a flood zone. :1�: j.�a r@l6l• ■ ra�f: j j r6j fi ■ ■: TERMINOLOGY: NGVD29 — Established in 1929, as the vertical control datum establishing vertical control surveying. NAVD88 — Proposed in 1988, a more sophisticated method for vertical control surveying. Conversion between NGVD29 and NAVD88 is an increase of 2.3' for our area. :1�: j.�a r@lGl• ■ ra�f: j j [Gj fi ■ ■: ❖ Determine if FEMA's BFE of 9.0' is correct? 1978 The Flood Map showed a Base Flood Elevation of 6.0' NGVD29. oe AM, � \ ZONE A ' a a> ION :6 \I n AVr ZONES ALVAPAnl) WA 1't fVPl�l �i5 Island . O L UNS / Avr y WPOVOIYC Ae AY ZONE B B 1. •.: (ON CSI • • re ■2r -�i �riTiTl In Late 2003 FEMA Converted its paper Flood Maps to Digital Maps, but at the same time converted the maps to '�AVD33. Flood Levels were converted and rounded using various conservative assumptions. • • re ■2r -�i �riTiTl NGVD29 was converted to NAVD88: 6.0' + 2.3'= 8.3' NAVD88 For some reason this was rounded UP to 9.0' instead of DOWN to 8.0'. Confirmed Error by FEMA's Contractor. • • re ■2r -�i �riTiTl Determine BFE based on recent Data. DHI performed engineering analysis of National Oceanic Atmospheric Administration (NOAH) tide gages using FEMA approved methods. Consultants analyzed the data two different ways. • • re ■2r Results: -�i �riTiTl Base Flood Elevation is 7.7' today. (8.0') Waves in harbor from ocean are minimal. Waves generated from wind require further analysis. r -1 40 r r] L To be considered as a coastal levee, a 2 -foot freeboard is required on the seawall. Top of Seawall - 11.0' BFE - 9.0' Proposed Top of Seawall - 10.0 Min Proposed n u i� California Coastal Analysis and Mapping Project -A study to update the Flood Insurance Rate Maps. Open a dialogue with FEMA and share the results of our study so as to ensure the BFE is at 8.0'. Balboa Island Sea Wall Height &Drainage Existing Drainage System on Balboa Island INS BALBOA ND v' v` P JV 4ie `P PO uPP P (yP/ aW BALBOA AVE E� V QPP Q > C o s Q a a w O m x z u d PARRAVE +.,� �P ♦QeP �P� o� �e BAY FRONT ALL Y S lS /'s., \ O f/ 1 4 } } BALBOA ISLAND Tide Valves Protects the Island from Flooding due to High Tides Currently Manually Operated Manually Operated with Valve Key Power Assisted with Manually Operated Up /Down Switch New Rubber Tide Valve (Check Valve) ➢ No Moving Mechanical Parts - Silent, Non - Slamming ➢ Non — Corrosive - Durable Rubber Construction ➢ Minimal Maintenance and Periodic Inspection Needed ➢ Around 1" of Water Pressure Opens Valve helping Eliminate Standing Water ➢ Simple Installation. Estimated 25 -Year Life I S i Low Flow Open Full Flow Open Closed Against Tide New Rubber Tide Valve (Check Valve) 1' ,IM ` hik" HOP 13 2012 Existing Island Seawall and Flood Protection Conditions Existing FEMA Base Flood Elevation = 9.0' (NAVD88) Finish Floor's at or above 9.0' will pay a lower Flood Insurance Rate. Finish Floor's below 9.0' will pay a higher Flood Insurance rate.. Existing Base Flood Elevation (BFE) = 9.0' EL7.6'to87 Top Existing Seawall EL65' 'Nalkwa /' EL 9.tY (Ex. 6Y-11.6') Finish Floor EL 6.4' Top of Curti 'hater Table Existing Island Seawall and New FEMA Base Flood Elevation Possible New FEMA Base Flood Elevation = 8.0' (NAVD 88) Requires Letter of Map Revision (LOMR) by FEMA Finish Floor's at or above 8.0' will pay a lower Flood Insurance Rate. Finish Floor's below 8.0' will pay a higher Flood Insurance Rate. Existing Base Flood Elevation Possible New FEMA Base Flood Elevation (BFE) = 8.0; EL. 7.6' fo 8.7' Top Existing Seawall --- -- - - -- .............. —.J EL 9.0' (Ex 6.1' - 11.6) Finish Floor EL 6.4' Top of Curb ■,,, ........................... ............... Water Table EL 6.5' Walkway Proposed New FEMA Certified Island Seawall with Drainage System That would provide 100 Year Storm Protection ♦ Island Removed from prior FEMA Flood Plain with Seawall Elev. = MY (Stillwater Elev. of 8.0' + 2.0` of Freeboard) * Base Flood Elevation Determined by Drainage System -100 Year Storm Water Elevation. • Adjacent Grade of Structure must be above 100 Year Storm Water Elevation to be out of the Flood Plain and will pay a lower Flood Insurance Rate Top of New Seawall EL 10.0' All Water EL a.0 Adjacent Grade Elev. needs to be above 100 food Eley. EL 6.4' Tap of Curb Water Table EL 6.5' Walkway N New Base Flood Elevation Proposed at or below Street Curb Elevation +- NEW DRAINGE SYSTEM CONCEPT J� Q F' 9 > > > w PP Q Q Q > a e9� QQ� PARK AVE O X102 Y O > z L SOUTH CONSOLIDATE GRAVITY DISC POINT WITH AUTO TIDE GATE PUMP STATION BACK UP pd ➢ Reduce Number of Discharge Points ➢ Automate Tide Values ➢ Provide High Water Pump -Out Capacity Sub - Terrain Storm Water Pump Station Will also Need to Develop Acceptable Flood Proof Solution for Ferry Landing 1114, 11 L J tv r .E M� A R K I _ I ,► I_ USE OTHER AUYU FERRY I W "1% �s i 1 FEMA to Process a Letter of Map Revision (LOMR) to Lower Base Flood Elevation from 9.0' to 8.0' & Collaborate with FEMA during the California Coastal Analysis and Mapping Project to ensure 8.0' BFE. Review and Provide Comments to the pending Sea Level Rise Policy Guidance Document to Ensure Ability to Construct and /or Maintain Necessary City /Harbor Flood Protection Improvements. Work toward the Eventual Upgrading or Replacement of Balboa Island and Other Critical Sea Wall Flood Structures. Duesti� Community Development Department Public Works Department Protecting and Providing Quality Public Improvements and Services