HomeMy WebLinkAbout07 - Harbor Area Management Plan - Amendment No. 1 to PSACITY OF NEWPORT BEACH
CITY COUNCIL STAFF REPORT
Agenda Item No. 7
December 11, 2007
TO: HONORABLE MAYOR AND MEMBERS OF THE CITY COUNCIL
FROM: Public Works Department
Fong Tse
949 - 644 -3321 or ftse@city.newport- beach.ca.us
SUBJECT: HARBOR AREA MANAGEMENT PLAN — AMENDMENT NO. 1 TO
PROFESSIONAL SERVICES AGREEMENT WITH WESTON
SOLUTIONS
RECOMMENDATIONS:
Approve an Amendment to the Professional Services Agreement with Weston
Solutions of Carlsbad, California, for a not -to -exceed price of $43,680 and authorize
the Mayor and City Clerk to execute the Agreement.
DISCUSSION:
On May 8, 2007, the City entered into a Professional Services Agreement (PSA) with
Weston Solutions (Weston) for the preparation of a comprehensive Harbor Area
Management Plan (RAMP). The plan will identify, prioritize, and address watershed
issues such as water supply, sediments, channel erosion, water quality, navigation,
habitat restoration, community access, and education programs for the Newport Harbor
as well as the Upper and Lower Newport Bays.
During Weston's work on the plan, it became apparent that in addition to the various
environmental, navigational, and planning issues that Weston is charged to address,
the potential of flood damage that could be caused by storms should also be studied.
Accordingly, staff requested and Weston provided the attached Flood Vulnerability
Study (FVS) proposal for the City's consideration.
The FVS will analyze. historic storm data, develop storm models, assess the City's
existing storm infrastructures, and develop strategies for implementing flood defenses.
Staff feels that the inclusion of FVS as a part of HAMP will provide a more integrated
master planning tool for the City.
Harbor Area Management Plan — Amendment No. 7 to Professional Services Agreement with Weston Solutions
December f f, 2007
Page 2
Environmental Review:
The required effort for preparing the Harbor Area Management Plan does not require
an environmental review.
Fundina Availability:
Sufficient funds are available in the following account for the project:
Account Description
Newport Coast Watershed Program
Prepared
I Engineer
Attachments: Amendment No. 1
Account Number Amount
7014- C5100912 $43,680
Total: $43,680
Submitted by:
St G. Badum
�P"u(c Works Director
AMENDMENT NO. 1
TO
PROFESSIONAL SERVICES AGREEMENT
WITH WESTON SOLUTIONS
FOR HARBOR AREA MANAGEMENT PLAN
THIS AMENDMENT NO. 1 TO PROFESSIONAL SERVICES AGREEMENT, entered
into this day of _ , 2007, by and between the CITY OF
NEWPORT BEACH, a municipal corporation, (hereinafter referred to as "City ") and.
WESTON SOLUTIONS, Inc., a Pennsylvania corporation whose address is 2433
Impala Drive, Carlsbad, CA 92008 ( "Consultant "), and is made with reference to the
following:
RECITALS
A. On May 8, 2007, CITY and CONSULTANT entered into a Professional
Services Agreement, hereinafter referred to as "Agreement', for the
preparation of a comprehensive Harbor Area Management Plan (RAMP).
The plan will identify, prioritize, and address watershed issues such as
water supply, sediments, channel erosion, water quality, navigation, habit
restoration, community access, and educational programs for the Newport
Harbor as well as the Upper and Lower Newport Bays.
B. City desires to enter into this Amendment No. 1 to reflect additional
services not included in the Agreement.
C. City desires to compensate Consultant for additional professional services
to be conducted for a Flood Vulnerability Study for inclusion as a part of
RAMP.
D. City and Consultant mutually desire to amend Agreement, hereinafter
referred to as Amendment No. 1, as provided here below.
NOW, THEREFORE, the parties hereto agree as follows:
1. Consultant shall be compensated for services performed pursuant to this
Amendment No.1 according to "Exhibit A" dated October 30, 2007
attached hereto.
2. Total additional compensation to Consultant for services performed
pursuant to this Amendment No. 1 for all work performed in accordance
with this Amendment, including all reimburseable items and subconsultant
fees, shall not exceed Forty Three Thousand, Six Hundred Eighty and
no /100 Dollars ($43,680.00).
3. Except as expressly modified herein, all other provisions, terms, and
covenants set forth in Agreement shall remain unchanged and shall be in
full force and effect.
IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 on
the date first above written.
APP OVED AS TO FORM:
City Attorney tt��
for the City of Newport Beach
ATTEST:
By:
LaVonne Harkless,
City Clerk
CITY OF NEWPORT BEACH, .
A Municipal Corporation
27
Mayor
for the City of Newport Beach
CONSULTANT:
By:
(Corporate Officer)
Title:
Print Name:
By:
(Financial Officer)
Print Name:
Attachments: Exhibit A — Scope of Services and Billing Rates
f:Wserslpbwlshareftgreements5ty 07-08%WestaaHAMP Amend -1.doe
October 30, 2007
Mr. Robert Stein, P.E.
Principal Civil Engineer
Public Works Department
City of Newport Beach 3300
Newport Boulevard
Newport Beach, CA 92663
Subject: Vulnerability Study of the Newport Harbor Area
to Flooding by Extreme Tides
Modification' of Scope for
Harbor Area Management Plan
Dear Mr. Stein:
We are pleased to provide you this proposal for conducting a Flood Vulnerability Study
of the Newport Bay as a modification to the existing contract for the Harbor Area
Management Plan. Dr. Brett F. Sanders will be completing this study as outlined below.
Introduction
The highest high tides in California threaten flooding of low -lying terrain and result from
the coincidence of extreme astronomical tides and storm induced sea level changes. in
Newport Harbor, the highest recorded tide was measured January 28, 1983 during a
devastating El Niiio storm that impacted the entire California coastline. On the Balboa
Peninsula, 175 homes and business were damaged and water flooded Balboa Boulevard,
Newport Boulevard as well as the Finley residential area. The extreme tide was a
consequence of atmospheric conditions, i.e., low atmospheric pressure and wind, as well
as long -term inter- annual effects including El Nino.
Sea levels have been rising for decades, but higher rates are forecast for the coming
century. This will impact not only mean sea level (MSL), but high water levels as well.
Data reported for Los Angeles and La Jolla show that mean higher high water (MHHW)
rose slightly faster than MSL over the past 50 years. Estimates of future sea level rise at
Newport Harbor fall in the range of 1 -3 ft/100 years range for Newport Harbor. A United
States Environmental Protection Agency (USEPA) study put these figures in a
probabilistic perspective, suggesting there was a 50% chance that sea level rise would
exceed 0.4, 0.7 and 1.5 ft by 2025, 2050 and 2100, respectively, and a 10% chance that
sea level rise would exceed 0.6, 1. t and 2.9 ft by 2025, 2050 and 2100, respectively.
There is also evidence that North Pacific cyclones, which bring storm weather to
Southern California in Winter, have intensified over the past 50 years. This has
contributed to higher high tides and is thought to be a consequence of warmer ocean
water. Future extreme tides constitute the most immediate flooding threat to low -lying
Mr. Robert Stein, P.E. ��
City of [Newport Beach, Flood Vulnerability Study
October 30, 2007
Page 2
coastal communities such as the [Newport Harbor area, and are likely to be amplified by
increasing sea levels.
Coastal communities are in a position to plan for extreme tides. Their occurrence is
actually quite predictable based on semi- annual and inter - annual cycles. In fact, there are
only a few multi -day periods each Winter when extreme tides threaten the California
coast. Only the most extreme cases are likely to cause flooding in the near future and the
severity of extreme tides will hinge on atmospheric conditions. The worst - case - scenario
is a strong low- pressure storm approaching the California coastline from the Gulf of
Alaska coincident with an extreme tide, as in January of 1983 shown in Figure 1.
Proposal
We propose a study to evaluate whether and to what extent flooding of the Newport
Harbor area is likely to result from future extreme tides due to the coincidence of extreme
astronomical tides and storm induced sea level changes; and predicted flooding under this
scenario in addition to probabilistic increases in future sea level rise. A set of
hypothetical design tides will be developed to reflect a high, moderate and low
probability of occurrence. Then, a multidimensional hydrodynamic model will be applied
to simulate inundation likely to result from these tides.
It is expected that this study will support a number of activities that the City can pursue to
prepare for extreme tides, and incorporate into its Harbor Area Management Plan. In
terms of planning, the City may use the results of this study to prioritize improvements of
permanent or temporary sea defenses (bulk heads, seawalls, etc.) and drainage
infrastructure including pump stations, to assess whether the degree is flooding would
warrant evacuations, to effectively deploy and position emergency response staff, and to
assess the viability of critical transportation links (e.g., Newport Boulevard) for
emergency response.
The City recently made a substantial investment in a LiDAR terrain data, the best source
of remotely sensed terrain data for flood inundation studies. The proposed study would
provide added value to this substantial City investment.
The City has invested in other modeling studies to address coastal water quality and
habitat objectives. In particular, Everest International Consultants has applied RMA2 to
simulate tidal transport of urban runoff, and contaminants associated with urban runoff,
in Newport Bay. While the numerical methods adopted by RMA2 make it well suited for
tidal time -scale simulations of flow and contaminant transport, RMA2 is not well suited
for detailed, street -level simulations of flood inundation which is the aim of this study.
BreZo, on the other hand, is ideally suited for this task. .
The study will include the following tasks:
Mr. Robert Stein, P.E.
City of Newport Beach, Flood Vulnerability Study W�'
October 30, 2007
Page 3
_Task 1: Review and svnthesize terrain data sources. Accurate terrain data are crucial for
flood inundation modeling. Therefore, this study will begin with a review and synthesis
of terrain elevation data likely to be useful for this study including: (1) Bay bathymetry
data (land below water) collected by the US Army Corps of Engineers (2002, 2005), (2)
City of Newport Beach LiDAR terrain data (2006), (3) Upper Newport Bay LiDAR
terrain data collected by the US Army Corps of Engineers (2002), (4) Offshore
bathymetry data distributed by the NOAA Geophysical Data Center (NOAA/GDC)
bathymetry data and (5) coastline UDAR data distributed by NOAA Coastal Services
Center (NOAA/CSC).
These data are likely to adopt different datums and/or projections. In addition, the
coverage of these data sources is not presently clear. In this task, we will convert all data
to the California State Plane Coordinate System (Zone VI) using NAVD88 for vertical
control. Furthermore, we will review the coverage and accuracy of all data sources and
identify the most accurate data sources for the proposed modeling. This is expected to
include the recent City UDAR survey for above -water areas around the Bay and Corps
bathymetry data for the below -water areas of the Bay. A map will be prepared showing
the coverage and quality of relevant data sources.
Deliverable: Interim Report I describing the coverage, accessibility and quality of
terrain data for flood inundation modeling.
Task 2• Develop hypothetical design tides Records and reports on extreme tides in
California will be reviewed first, focusing on information relevant to Newport Harbor. A
set of design tides will then be developed to reflect a range of likelihoods based on a 25,
50 and 100 year planning horizon. The specifics of this have yet to be determined, but
one possibility is to take the tide record from January 28, 1983 tide as a base case, and to
add an uniform offset consistent with EPA sea level rise projections. By running the
flood inundation model several times using increasingly larger offsets, a range of
flooding scenarios will be depicted corresponding to decreasing probability.
Deliverable: Interim Report 2 presenting a set of design tides for subsequent flood
inundation modeling.
Task 3: Review of sea defense infrastructure Bulk heads protect several parts of Newport
Bay from high Bay levels. Knowledge of the extent of this infrastructure, as well as its
exact height, is essential for an accurate depiction of ocean flooding. In addition, a review
of drainage infrastructure will be needed to ascertain routes by which ocean flood waters
may bypass sea defenses (e.g., through storm drain system) and cause flooding. This task
will require support from City staff and involve a site visit around the perimeter of
Newport Harbor.
Deliverable: Interim Report 3 presenting an overview of sea defense infrastructure in
the Newport Harbor area.
Robert Stein, P.E.
City of Newport Beach, Flood Vulnerability Study �
October 30, 2007
Page 4
Task 4a: Prepare a computational Qrid for model simulations A model grid will be
prepared to support flood inundation modeling. The grid will adopt a variable resolution
that balances the demands for accuracy and computational efficiency. Large
computational cells will be used in deep water that is always flooded, and small
computational cells will be used in areas where inundation of normally dry land is
predicted. In addition, the model grid will be aligned with bulk heads and new modeling
techniques will be used to realistically simulate overtopping. The resolution of the grid
will be sufficient resolve surface flow along streets. Quality control checks will be made
to ensure that model predictions of flood zones are not grid dependent.
Task 4b: Perform flood simulations A 2D numerical model developed by Professor
Sanders, BreZo, will be applied to simulate flooding. The model has previously been
applied in a number of coastal and inland flow simulation applications, and there are a
number of published papers that validate its use. Electronic versions of Professor
Sanders' papers can be accessed from his university web page
hitp://aram.eniz.uci.edu/-bEs—/sanders2.htm] or a hard copy can be provided upon request.
In each simulation, flow conditions will be forced by two factors: the design tide and
storm water inputs from major tributaries that drain to the Bay. The model will assume
that all terrain is impermeable, implying no infiltration or drainage of flooding ocean
water into storm sewers. In addition, the model will not consider precipitation directly.
This approach will allow the model to isolate the impact of ocean levels on flooding. At a
future time, BreZo could be coupled to a City drainage model to see how readily ocean
Water flooding can be mitigated with existing infrastructure, or to design improvements
to the sewer infrastructure to better cope with ocean water flooding. However, these tasks
are outside the scope of the present study. An executable version of the flood model used
for this study will be provided to the City upon completion of the study to support
additional modeling if the need arises (e.g., simulations could be repeated with higher
bulk -head heights or a different design tide).
Task 4c• Prepare flood inundation maps corresponding to extreme tides. The results of
model simulations will be processed and distilled into a set of flood inundation maps.
These maps will depict regions of inundation corresponding to design tides of various
heights.
Deliverable: A Project Report incorporating the previous reports and presenting the
flood modeling methodology, flood modeling results, a discussion of the vulnerability
of the Newport harbor area to flooding, and recommendations for flood hazard
mitigation.
Project Timeline
Start Date November 12, 2007
Mr. Robert Stein, P.E.
City of Newport Beach, Flood Vulnerability Study
October 30, 2007
Task I completion and Interim Report t
Task 2 completion and Interim Report 2
Task 3 completion and Interim Report 3
Task 4 completion Draft Final Report
Task 5 (Meetings)
Project Cost
December 21, 2007
January 18, 2008
February 15, 2008
April 25, 2008
Page 5
The proposed project is not to exceed a cost of $43,680 including overhead. Invoices will
be submitted for time and materials upon the completion of each task.
Task
Hours
Rate (Dr. Sanders) Dr. Pohl
Task Total
1
40
$165
$6,600
2
40
$165
6,600
3
48
$165
7,920
4
120
$165
19,800
5
16
$165 $185
2.760
Total
$43,680
Please do not hesitate to call me at 760 -497 -3318 or Dr. Sanders at 949 - 824 -4327 with
any questions on this proposal.
Very truly yours,
Weston Solutions, Inc.
David H. Pohl, P.E., Ph.D.
cc: Dr. Sanders (UCI)