county of alameda public works agency · philip williams & associates, ltd . recommendation:...

FLOOD CONTROL AGENDA __March 3, 2009

COUNTY OF ALAMEDA PUBLIC WORKS AGENCY 399 Elmhurst Street. Hayward, CA 94544-1307 (510) 670-5480

February 11, 2009

The Honorable Board of Supervisors County Administration Building 1221 Oak Street Oakland, CA 94612

Dear Board Members:

SUBJECT: EXECUTE MODIFICAnON NO.2 TO AGREEMENT NO. 1398 AUTHORIZING AN INCREASE IN CONTRACT AMOUNT WITH PHILIP WILLIAMS & ASSOCIATES, LTD

RECOMMENDATION:

Approve and authorize the President of your Board to execute Modification No.2 to Agreement No. 1398, between Alameda County Flood Control and Water Conservation District and Philip Williams & Associates, Ltd. (PWA, Ltd.), a SLEB certified, Oakland firm, (Principal: Jeffrey Haltiner; Location: Oakland, CA) to provide additional environmental hydrology professional services and increase the contract amount from $1,427,286 to $1,777,286, an increase of$350,000. There will be no change in the contract period of March 21,2006 through April 1,2010.

SUMMARY/DISCUSSION:

The initial contract (C-2006-90) between Alameda County Flood Control and Water Conservation District (District) with PWA, Ltd. in the amount of $869,922, with an expiration date of April 1, 2009, was approved on March 21, 2006. On June 12, 2007, Modification No.1 (C-1398) was approved that extended the contract expiration date to April 1, 2010, and added $557,364 to the contract. The major scope of the initial contract and Modification No. 1 was to develop detailed studies and plans to integrate two flood control channels, Old Alameda Creek and Alameda Creek, with the restoration of the Eden Landing Salt Ponds as part of the South Bay Salt Pond Restoration Project. PWA, Ltd. and their sub-consultants have substantially completed these tasks (including restoration plans for Ponds E8A/9/8X at Eden Landing).

During the execution of the original project scope, PWA, Ltd. has identified certain essential and integral elements required for the success of the proj ect. The District supports the specialized scope and does not have the in-house experience to do this environmental hydrology work. PWA, Ltd., has demonstrated that they have the skill sets and experience to efficiently work in this specialized area.

The $350,000 increase in the contract amount, with no change in term with PWA, Ltd., falls into the following five areas:

"To Serve and Preserve Our Community"

Honorable Board of Supervisors February 11,2009

1. Expansion of the initial design project

The District is proposing to combine the restoration of Ponds E8A19/8X with Ponds EI2/13 projects. The use of excess earth from the Ponds E8A19/8X project for the Ponds EI2/13 project is expected to eliminate the need to import material, speed implementation, and result in construction cost savings. Linking the projects also minimizes the total construction time, thereby limiting the impact on endangered species. .

2. Development of a Spartina monitoring plan

Spartina is an invasive plant that infests tidal marshes. It has been almost completely eradicated from the Eden Landing tidal area. This task will provide a scientifically sound plan for surveillance of tidal marsh at Eden Landing for invasive Spartina re-infestation, so that measures can be taken before it becomes an extensive problem again.

3. A study to identify the likelihood of extreme stream flows and tide levels

Practical experience has shown that periods of extreme stream flow often occur during periods of higher than predicted bay tides. This task consists of assessing the joint likelihood of extreme stream flows coinciding with extreme tides in the bay.

4. FEMA coordination

FEMA is updating bay tide levels that will guide the design of proposed new levees at Eden Landing. However, the release of the FEMA update is uncertain. This task will develop an approach to estimate the required levee crest elevation at Eden Landing pending release of the FEMA results.

5. Further development ofhydro-dvnamic model

This includes further development of the Eden Landing hydro-dynamic model, project management, continuation of the Alameda Creek water and sediment forum, and further development of the ID/2D morphological modeling for Alameda Creek.

The District anticipates that all activities associated with the contract modifications will be completed by the end of the contract period. A Request for Proposal will be conducted in the future if further work will be required.

SELECTION CRITERIA/PROCESS:

PWA, Ltd., with offices in Oakland, was selected at the outset of this project to provide the above services through a competitive consultant selection process meeting Agency guidelines. Public Works has determined that it does not currently have the qualified personnel to perform this service.

Honorable Board of Supervisors February 11, 2009

In May 2005, a combined Request for Qualifications and Request for Proposal was circulated to consultants on the Agency's SLEB list and in its consultant database, and was also advertised in local newspapers. A mandatory pre-proposal meeting was held on June 23, 2005. Nineteen consultants attended this meeting. Four of the consultants were known by County staff to have a SLEB classification. We received three proposals and these firms (Philip Williams and Associates, URS Corporation, and Stetson Engineers) were invited to an oral interview on August 8, 2005. A four-member selection committee (two in-house; one from the Coastal Conservancy and onefrom the Lower Alameda Creek Stewardship Committee) evaluated each firm's qualifications and oral interview. Finally, PWA, Ltd. was selected based upon the submitted proposals and interview results. Your Board approved a contract on March 21,2006.

Selection ofa new consultant in accordance with current selection policy andprocedure would delay the work for several months while conducting the selection process, negotiating and executing a contract, and orienting the new consultant to the work. It would also add to contract cost, in that the work completed to date would have to be reviewed by and transitioned to a new consultant. The current consultant has offices in Oakland; their performance to date has been excellent and their cost reasonable. In the interests ofexpeditious work completion, cost containment, and continuity of study philosophy and quality ofwork, it is requested that this contract be modified as recommended.

PWA, Ltd. has been certified as a SLEB (Certification #06-90848, expires 5/3112010).

FINANCING:

There is no impact on the County General Fund. The funding for the modification in the amount of $350,000 is available and budgeted in Zones 3A and 5, Organizations 21805 and 21807, Account 610261 (Professional and Specialized Services), Program 50600.

c: Patrick O'Connell, Auditor-Controller Audrey Beaman, County Counsel JeffHaltiner, PWA, Ltd.

DW/RJ/jcj Attachment

POD-FOES-Board Ltr-Mod #2 Agmnt-Philip Williams-3-3-09 Agenda.doc

Client#· 437 PHILIWILL DATE (MMlDDIYY)

ACORDn< CERTIFICATE OF LIABILITY INSURANCE 09/08/08I PRODUCER THIS CERTIFICATE IS ISSUED AS A MAnER OF INFORMATION

ONLY AND CONFERS NO RIGHTS UPON THE CERTIFICATEDealey, Renton & Associates HOLDER, THIS CERTIFICATE DOES NOT AMEND. EXTEND OR

P. O. Box 12675 ALTER THE COVERAGE AFFORDED BY THE POLICIES BELOW. Oakland, CA 94604·2675

INSURERS AFFORDING COVERAGE 510465·3090 David C. Eckman INSURED I INSURER A: The Travelers Indemnity Co of CT

Philip Williams & Associates, Ltd. INSURER B: Travelers Property Casualty Co. of A 550 Kearny Street, Suite 900 INSURER C: American Automobile Ins. Co. San Francisco, CA 94108·2522 INSURER 0: Liberty Insurance Underwriters, Inc.

INSURER E: Property & Casualty Ins Co of HartfoI

COVERAGES THE POLICIES OF INSURANCE LISTED BELOW HAVE BEEN ISSUED TO THE INSURED NAMED ABOVE FOR THE POLICY PERIOD INDICATED, NOTWITHSTANDING ANY REQUIREMENT, TERM OR CONDITION OF ANY CONTRACT OR OTHER DOCUMENT WITH RESPECT TO WHICH THIS CERTIFICATE MAY BE ISSUED OR MAY PERTAIN, THE INSURANCE AFFORDED BY THE POLICIES DESCRIBED HEREIN IS SUBJECT TO ALL THE TERMS, EXCLUSIONS AND CONDITIONS OF SUCH POLICIES, AGGREGATE LIMITS SHOWN MAY HAVE BEEN REDUCED BY PAID CLAIMS,

~t: TYPE OF INSURANCE POLICY NUMBER P~k!f.! ~1J~g~ p~~¥J 'i:~~~N LIMITS

A ~NERAL LIABILITY 6804866L448 09/01/08 09/01/09 EACH OCCURRENCE $1 000,000

X- COM MERCIAL GENERAL LIABILITY FIRE DAMAGE (Anyone fire) $300000

- =:J CLAIMS MADE W OCCUR "lED EXP (Anyone person) $10000

-PERSONAL & AnV INJURY $1000,000

-GENERAL AGGREGATE $2000000

GEN'L AGGREGATE LIMIT APPLIES PER: PRODUCTS ·COMP/OP AGG $2,000,000 ~ POLICY !Xl ~~ n LOC

E ~TOMOBILE LIABILITY 57UECUP9710 09/01/08 09/01/09 COMBINED SINGLE LIMIT

~ ANY AUTO (Ea accident) $1,000,000

- ALL OWNED AUTOS BODILY INJURY (Per parson) $

SCHEDULED AUTOS -~ HIRED AUTOS

I

BODILY INJURY

~

I

(Par accident) $ NON-OWNED AUTOS

-J PROPERTY DAMAGE (Per accidant) $

~RAGE LIABILITY AUTO ONLY· EA ACCI DENT $ ANY AUTO OTHER THAN EAACC $

AUTO ONLY: AGG $ B EXCESS LIABILITY CUP7169Y042 09/01/08 09/01/09 EACH OCCURRENCE $1000000 ~ OCCUR D CLAIMS MADE

I I

AGGREGATE $1,000,000 $=1 DEDUCTIBLE $

RETENTION $ $ C WORKERS COMPENSATION AND WZP80963958 07/01/08 07/01/09 X IWC ~T~I,~;" T 1°JbI-

EMPLOYERS' LIABILITY $1,000000E,L, EACH ACCIDENT

E.L. DISEASE - EA EMPL OYEE $1,000,000 E.L. DISEASE • POLICY LIMIT $1,000,000

D OTHER Professional IAEE1973670108 09/07/08 09/07/09 $2,000,000 per Claim I'-iabllity $2,000,000 Annl Aggr.

DESCRIPTION OF OPERATIONSILOCATIONSNEHICLES/EXCLUSIONS ADDED BY ENDORSEMENTISPECIAL PROVISIONS

GENERAL LIABILITY POLICY EXCLUDES CLAIMS ARISING OUT OF THE PERFORMANCE OF PROFESSIONAL SERVICES. Ref: Project 1683.00 Alameda Co. J-Pond Analysis.

(See Attached Descriptions)

CERTIFICATE HOLDER ! IADDmONALINSURED'INSURERLEITER: CANCELLATION

SHOULD ANYOF THEABOVE DESCRIBED POLICIES BE CANCELLED BEFORE THE EXPIRATION

Alameda County Public Works Agency DATE THEREOF, THE ISSUING INSURER WILL ENDEAVOR TO MAIL 3tL... DAYS WRITTEN

Attn: Sue Lewis, ESA NOTICE TOTHE CERTIFICATE HOLDERNAMED TOTHE LEFT, BUTFAILURE TODOSOSHALL

399 Elmhurst Street 399 IMPOSE NO OBLIGATION OR LIAIBILITYOF ANY KIND UPON THE INSURER,ITS AGENTS OR

Elmhurst Street REPRESENTATIVES,

Hayward, CA 94544 I

ACORD 25-5 (7/97)1 of 2 #M236481

A:<!IZED ;EPR;cNTAfb - DAC @) ACORD CORPORATION 1988

09-09-08P03:05 RCVO

•

MODIFICATION NO.2 OF AGREEMENT WITH Philip Williams & Associates, Ltd. (1/28/09)

This Modification No.2 of Agreement for Services is made and entered into by and between th Alameda County Flood Control and Water Conservation District, hereinafter referred to as DISTRICT, and Philip Williams & Associates, Ltd., hereinafter referred to as CONSULTANT.

WITNESSETH

Whereas, DISTRICT and CONSULTANT have previously entered into agreement C-2006-90, executed March 21, 2006 and SUbsequently modified said agreement by Modification No.1 (C-1398, executed June 26. 2007) to perform professional engineering stUdies related to the integration of three estuarine flood control channels with the South San Francisco Bay Salt Pond Restoration project in Hayward, Union City and Fremont, Alameda County, California. Zones 3A, 5 and 6; and

Whereas, DISTRICT desires to modify said agreement and its subsequent modifications to provide additional funds in the amount of $350.000.00;

Whereas, DISTRICT desires to add more detailed tasks to the existing scope of work.

Whereas, CONSULTANT desires to replace two sub-consultants on CONSULTANT'S team;

It is mutually agreed by DISTRICT and CONSULTANT to modify said agreement as follows:

A. AppendiX B, Payments to consultant, paragraph 1.1, the Not to Exceed amount is modified to read:

"The amount of compensation to be paid to Consultant for all services under this agreement shall riot exceed the sun; of $1 ,777,286.00."

B. Exhibit A-1 - Scope of Project is revised as attached effective January 28,2009 and continuing through the remainder of contract period.

C. AppendiX A, Services to be PrOVided by CONSULTANT, Paragraph 1.2, CONSULTANT Team, is modified to add Noble Consultants and GeoMatrix Consulting and remove Geo Resource Consulting and Brown & Caldwell.

It is understood and agreed that all other terms and conditions of Agreement C-2006-90 shall remain in full force and effect as if fufly set forth herein.

EXECUTION DISTRICT CONTRACTOR

By: Philip Williams &Associates. Ltd. President, Board of Supervisors, County of Alameda. State of California

By:~/~ Approved as to form:

ichard E. Winnie, County Counsel Vice p)eSident Title _

By: ~a;fV\~ 9Y -3tJ 8"3e-05 Deputy County Counsel Federal [0 Number

By signing above, signatory warrants and Date: represents that he/she executed this Agreement

in hislher authorized capacity and that by his/her signature on this Agreement, he/she or the entity upon behalfof which he/she acted, executed this Agreement.

81%

$ 1.439,477

3%

$ 44,870

5%13%

$ 232,2851 $ SO,9n

61%

1,081,345

original I I modification _modlflcatJon.2 budget t1 budget %\'~<:f\c /~~'7 ", budget

BUDGET SUMMARY

PWA Brown and I

EDAW I SFEI r;:c:eo

EOA I DHI I Noble I GeoMatrtx I Contract Total I Caldwell Resources I H.T. Harvey I

sLEB%

sLEB FEES I $

PWA Project Team - budget summary

ACFCD South Bay Salt Pond Integration

Integration of Three Flood Control Channels with the

South Bay Salt Pond Restoration Project

Scope of Work

Prepared for

Alameda County Flood Control and Water Conservation District

Prepared by

Philip Williams & Associates, Ltd.

With

SFEI DHI

EDAW

GeoMatrix Consulting

Noble Consultants

EOA

HT Harvey & Assoc.

REVISED 2/11108

PWA REF. # 1825

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TABLE OF CONTENTS

Page No.

3. TASK .01 - EDEN LANDING MODEL SETUP (COMPLETE) 5

4. TASK .02 - ALAMEDA CREEK FLOOD CONTROL CHANNEL (COMPLETE) 6 4.1 Define supplemental alternatives - COMPLETE 6

4.2 Geomorphic Evaluation - COMPLETE 6

4.3 Hydrodynamic Modeling - COMPETE 8

4.4 Levee Assessment - COMPLETE 8

4.5 Opinion of probable costs - COMPLETE 8

4.6 Identify Preferred Alternative - COMPLETE 8 4.7 Conceptual Design Report - COMPLETE 8

4.8 Upstream Assessment - COMPLETE 9

5. TASK .03A - PHASE I RESTORATION PROJECT PRELIMINARY DESIGN (COMPLETE)10 5.1 Phase I Project Definition - COMPLETE 10 5.2 Breaches and Marsh Restoration Earthwork - COMPLETE 10 5.3 Levee Enhancement - COMPLETE 10 5.4 Geomorphic Evaluation - COMPLETE 11

5.5 Hydrodynamic Modeling - COMPLETE 12 5.6 Opinion of probable costs - COMPLETE 12 5.7 Phase I Conceptual Design - COMPLETE 12 5.8 Breaches and Marsh Restoration Earthwork - COMPLETE 12 5.9 Levee Enhancement - COMPLETE 13 5.10 Pond EI0 Levee Improvement Preliminary Design - COMPLETE 13 5.11 30% design submittal - COMPLETE 14 5.12 subconsultants 14

5.12.1 EDAW -COMPLETE 14 5.12.2 HT Harvey - COMPLETE 14

3. TASK .03B - PHASE I RESTORATION PROJECT FINAL DESIGN (REVISED SCOPE) 15 3.13 Design Phase Hydrodynamic modeling - IN PROGRESS 15 3.14 Final design submittals - IN PROGRESS 16 3.15 Design Team Integration - NEW TASK 18

3.16 subconsultants 19 3.16.1 Brown & Caldwell- COMPLETE 19 3.16.2 GeoResources - COMPLETE 19

3.16.3 Noble consultants - NEW SUBCONSULTANT 19

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3.16.4 Geomatrix- NEW SUBCONSULTANT 19

4. TASK .04 - LAGUNA CREEKILAKE ELIZABETH 20 4.1 Lake Elizabeth Management Plan - IN PROGRESS 20 4.2 Laguna Creek project - IN PROGRESS 20

,5. TASK .05 - PROJECT MANAGEMENT & COORDINATION 21 5.1 Project management and coordination - IN PROGRESS 21 5.2 Coordination with other projects & agencies - COMPLETE 21 5.3 Technical Support for Corps Shoreline Study - IN PROGRESS 22 5.4 EOA - IN PROGRESS 22

6. TASK .06 - EXPENSES (COMPLETE) 23 6.1 PWA reimbursable expenses - COMPLETE 23 6.2 Watershed Sciences - COMPLETE 23 6.3 Storesund Consulting - COMPLETE 23 6.4 Towill Inc. - COMPLETE 23

7. TASK NUMBER NOT USED 24









16. TASK .16 - DUBLIN GEOMORPHIC MONITORING 25 16.1 Project Initiation - COMPLETE 25 16.2 Site Reconnaissance/Establish Monitoring Program - COMPLETE 25 16.3 annual monitoring and Reporting - IN PROGRESS 25

17. TASK .17 - EDEN LANDING LEVEE DESIGN DEVELOPMENT (COMPLETE) 26 17.1 Initial Assessment - COMPLETE 26 17.2 Preliminary Design - COMPLETE 26

18. TASK .18 - SFEI ALAMEDA CREEK SEDIMENT 28 18.1 PWA Oversite of SFEI Sediment STudy - COMPLETE 28 18.2 SFEI Alameda Creek Sediment Study - COMPLETE 28 18.3 SFEI Alameda Creek SEdiment Forum - NEW TASK 28 18.4 SFEI Data support for and review ofDHI model- NEW TASK 28


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18.5 SFEI Dry Creek reconnaissance - NEW TASK 29

18.6 SFEI Spartina Management Plan - NEW TASK 29

19. TASK .19 - DID ALAMEDA CREEK MODELlNG 31

19.1 PWA Oversite of Dill Modeling - COMPLETE 31 19.2 DHI modeling of Alameda Creek - COMPLETE 31 19.3 Additional DHI modeling of Alameda Creek - NEW TASK 31

20. TASK .20 - JOINT PROBABILITY FLOOD ANALYSIS (NEW TASK) 32 20.1 Project Initiation 33 20.2 Hydrologic data collection and analysis 33 20.3 Bay Water Level Data Collection and analysis 33 20.4 Joint Probability analysis 34

20.5 Joint Probability Criteria 34

20.6 Draft and final technical memorandum 35

21. TASK.21-FEMA TECHNICAL ASSISTANCE (NEW TASK) 36


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3. TASK .01 - EDEN LANDING MODEL SETUP (COMPLETE)

The Eden Landing project area generally encompasses the salt ponds and tidal areas lying between ACFCC and Highway 92, and includes ACFCC (SF Bay to Ardenwood) and OAC (SF Bay to 1-880). PWA will set up a MIKE Flood hydrodynamic model of the Eden Landing area to evaluate existing flood performance and test flood management project alternatives, consistent with previous hydrodynamic modeling performed for the District. MIKE Flood is a hydrodynamic modeling platform that links 1dimensional channel modeling (MIKE 11) with 2-dimensional floodplain modeling (MIKE 21). A MIKE Flood hydrodynamic model was developed by URS (2004) that consists of one-dimensional (ID) MIKE II models of the fluvial channels and a two-dimensional (20) MIKE 21 model of the Eden Landing pond complex between OAC and the ACFCC.

This task includes data collection, review of existing models are reports, and model setup for existing conditions. Scenario modeling specific to other tasks is included in the scope of work for those tasks.

With help from the District, we will obtain and review relevant data, studies, reports, models, maps, plans and analyses that relate to the Eden Landing project area. This scope of work assumes that an existing

MIKE Flood model will be available to PWA for use in evaluating the flood management performance of various project elements in the Eden Landing area. PWA will update the model with the most recent channel cross-sections available from the District, and expand the model as needed to cover the ponds north of OAC using the pond bathymetry collected by the USGS for the South Bay Salt Pond restoration project (SBSP).

Topographic and bathymetric data required for model set-up has been collected by the USGS, including a 2004 pond bathymetry survey of the ponds containing water, a 2004 LiDAR survey of the intertidal mudflats, dry ponds, and upland areas, and a 2005 hydrographic survey of the South Bay. The data sets have been combined into a digital terrain model (DTM) for use on the SBSP Restoration Project. Hydrodynamic data required for model boundary conditions has been collected as part of the SBSP Restoration Project (PWA, 2005 - Modeling Methods and Strategy Report). The existing conditions periods analyzed for SBSP include summer 2001 (dry year) and winter 2004 (wet year). The SBSP DELFTJD model will be used to supply appropriate downstream Bay boundary conditions, including water levels and velocities. Upstream inflow conditions will be estimated based on the best readily available information, such as information from existing upstream flow gauges supplemented with

hydrological estimates and adjustments, if required.

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4. TASK .02 - ALAMEDA CREEK FLOOD CONTROL CHANNEL (COMPLETE)

Under this task, PWA will evaluate alternatives for modifying the ACFCC between Ardenwood

Boulevard and San Francisco Bay to integrate with SBSP and improve flood management performance.

The District has completed initial feasibility studies for improving flood management in this reach of the

ACFCC. PWA will build upon previous studies by developing and evaluating "supplemental alternatives"

that address both flood management and integration with SBSP. Alternatives development will be informed by several related subtasks: geomorphic evaluation, hydrodynamic modeling, levee

assessments, and cost estimating. PWA will produce a draft and final report summarizing the

supplemental alternatives assessment and identifying a preferred alternative. PWA will submit the draft to

the District for review and respond to the District's comments in the final version.

4.1 DEFINE SUPPLEMENTAL ALTERNATIVES - COMPLETE

PWA will develop an initial description of supplemental alternatives proposed for consideration by the District, based on a review of previous reports and our experience from similar projects. Supplemental alternatives may include lowering or removing the northern levee along ACFCC, and allowing scour of

ACFCC in combination with adaptive management actions. In addition, we recommend that the District

consider revisions to the three alternatives already assessed in the initial feasibility studies. For example, allowing the remnant slough channels inside the ponds to scour over time in response to natural tidal

currents; excavating levee breaches to their long-term depth (circa several feet below mean lower low water) and large enough to allow conveyance of full tidal exchange between the creeks and the ponds

from the time of breaching; and evaluation of the likely long-term performance of the high flow spillway. Consideration of alternatives will also include introduction of tidal flow to the "P" line and the "J" ponds.

We will work with the District to define three supplemental alternatives for evaluation in this study. PWA will compare the performance of the three alternatives to a No Action alternative, considering geomorphic

changes expected to occur once the Eden Landing salt ponds are breached.

4.2 GEOMORPHIC EVALUAnON - COMPLETE PWA will perform a geomorphic evaluation of each of the three alternatives in order to define likely

scenarios for site conditions shortly after project implementation and for site evolution in the long-term.

In our evaluation, PWA will consider the following geomorphic changes with the potential to affect flood

mitigation and habitat restoration: • Pond/wetland sedimentation • Flood control channel scour

• Levee erosion • Remnant slough scour (if applicable) • Breach scour (ifapplicable)


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• Tides within ponds

The geomorphic evaluation will be used to define conditions for short- and long-term modeling scenarios.

Short-term simulations will model initial conditions immediately after levee breaching, assuming existing

pond bathymetry and channel geometries remain unchanged (no tidal scour or sedimentation). The longterm conditions will be evaluated for both "worst case" and "most likely" conditions. The worst case

scenario will include existing channel geometries (assuming no channel scour), sea level rise, and

projected marshplain sedimentation which will raise the ponds to natural marshplain elevations (around mean high water). The long-term pond bathymetry generated as part of the SBSP landscape-scale geomorphic analysis will be used as part of this task. This scenario represents the worst case for potential future flood protection.

For the most likely scenario, we will consider sea level rise and updated model bathymetry representing

the most probable future conditions, including tidal scour. The bathymetry will also be updated to account for marsh sedimentation. These simulations will provide estimates of the sustainable flood management

performance provided by the flood control channels and the restored ponds. The results of the modeling will also inform the adaptive management plan by identifying performance measures, such as the desired

and achieved tidal regime within the ponds, and potential locations for monitoring.

Table I summarizes the geomorphic scenarios that will be defined under this task and utilized in model

simulations comparing alternatives; additional runs may be necessary to assess extreme flood conditions.

Table 1 Simulation Scenarios

Simulation Timin2 Comments

Existing Conditions Current Existing levees and channel geometry

No Project Long-Term Includes projected sea level rise

Alternative I

Short-Term

Immediately after breach

Existing creek channel geometry (no scour)

Existing pond geometry Alternative 2

Alternative 3

Alternative 1 Long-Term

"Worst Case"

Existing Creek channel geometry (no scour) Projected marshplain sedimentation, with developed channels

inside the ponds Includes projected sea level rise

Alternative 2

Alternative 3

Alternative 1

Long-Term "Most Likely"

Long-term creek channel cross-sections based on hydraulic

geometry calculations (including scour) Projected marshplain sedimentation, with developed channels


Alternative 2

Alternative 3


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4.3 HYDRODYNAMIC MODELING - COMPETE The existing conditions model developed under Task I will serve as a base for developing models of the proposed alternatives. The model will allow for comparisons between existing and proposed conditions, among differing alternatives, and between short-tenn and long-tenn conditions following restoration.

4.4 LEVEE ASSESSMENT - COMPLETE

All the ACFCC alternatives identified through the SBSP project include construction of a perimeter flood control levee east of the Eden Landing ponds. In this task, PWA will provide a feasibility assessment with for constructing a continuous perimeter flood control levee inboard of the Eden Landing salt ponds to protect urban areas.

In close coordination with both SBSP and the District, PWA will evaluate the levee alignment from Highway 92 to the ACFCC. We will coordinate levee alignment with the Corps Shoreline Study, SBSP project, and FEMA San Francisco Bay Coastal Re-mapping Study (as possible) to promote consistency with these related projects. For consistency with the SBSP project, the levee design will facilitate wetland restoration along the side of the levee and recreational use on the levee crest. PWA will review existing data and reports to identify possible conflicts with interior drainage systems and impacts to the "J" ponds and other facilities inboard of the proposed levee. We will recommend approaches for resolving potential conflicts. PWA will also advise the District about the feasibi lity of undertaking the construction of this levee as a USACE project.

4.5 OPINION OF PROBABLE COSTS - COMPLETE As part of the alternatives evaluation, we will develop conceptual-level opinion of probable construction costs for each alternative. In estimating costs, we will focus on identifying the relative cost differences among the alternatives, rather than total costs, which is difficult to estimate in this early stage of design development. PWA will use cost estimating data developed by URS for the initial feasibility studies and data developed by PWA and Brown and Caldwell for SBSP and the Napa River Marsh Restoration. We will also try to obtain construction bid prices for similar construction projects from the District, Cargill,

and other local clients.

4.6 IDENTIFY PREFERRED ALTERNATNE - COMPLETE The results of the modeling, empirical analyses, cost estimates and other evaluations will be used to compare the alternatives to existing conditions and the No Action alternative. In consultation with the District, PWA will identify a preferred project alternative for the lower reach of ACFCC.

4.7 CONCEPTUAL DESIGN REPORT - COMPLETE PWA will produce a report that summarizes the results of the analyses, identifies the preferred project alternative, and describes the alternative at a concept level. PWA will submit one draft to the District for review and respond to the District's comments in the final version.


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4.8 UPSTREAM ASSESSMENT - COMPLETE

PWA will provide technical support and input to subconsultants SFEI and DRI to integrate analyses perfonned under this task with their studies of the upstream Alameda Creek watershed.


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5. TASK .03A - PHASE I RESTORATION PROJECT PRELIMINARY DESIGN (COMPLETE)

Under this task, PWA will assist the District in developing a project in the Eden Landing area to coincide with Phase 1 of the SBSP project. This scope of work assumes that the Phase I project will include tidal restoration of ponds E8A and E9 and E8X by breaching into OAC, and development of a monitoring plan to document the geomorphic response of the OAC channel and the ponds. It is anticipated that this project will demonstrate an increase in channel scour associated with salt pond levee breaching or removal.

5.1 PHASE I PROJECT DEFINITION - COMPLETE In close consultation with the District, PWA will develop a conceptual plan for restoration of Ponds E8A, E9 and EX. The plan will qualitatively describe levee breaching and/or lowering to introduce tidal circulation from OAC into the ponds. PWA will produce a memorandum that describes the conceptual plan in sufficient detail to initiate environmental review within the SBSP project.

5.2 BREACHES AND MARSH RESTORATION EARTHWORK - COMPLETE PWA will design earthwork features associated with tidal restoration including levee breaching and/or lowering to reintroduce tidal action and blocking or filling borrow ditches. PWA will locate and size breaches and ditch blocks based on existing site conditions (e.g. vegetation, soils, hydrology), construction feasibility and our experience with similar projects. Breaches would likely be sized to initiate tidal action and allow further widening through natural scour.

Based on our experience with other salt pond sites, it is likely that historic channels will scour on their own, making extensive channel excavation unnecessary. As an exception, channels may be excavated to address gypsum accumulation in the ponds. For budgeting purposes, we have assumed that the design may include excavation of one main channel in Pond 8A to facilitate channel scour. The basis of design for marsh restoration features will rely heavily on the geomorphic assessment developed above.

5.3 LEVEE ENHANCEMENT - COMPLETE We assume that the separation levee between Ponds E9/E8X and Pond E14 will need to be enhanced to protect managed ponds to the north. The PWA team will design enhancements to the existing levee that meet SBSP requirements (not FEMA standards). We anticipate that enhancements will include raising the levee crest to reduce the frequency of overtopping and/or widening and/or reinforcing the levee for increased erosion resistance. Levee enhancements would be a coordinated effort of geotechnical, hydraulic and civil design.

PWA will develop a design configuration for the enhanced levee based on our flood analysis and estimation of erosion potential. We anticipate the levee design will include a vegetated terrace to dissipate wave energy, rather than arrnoring. GeoResources will evaluate stability and potential settlement of the enhanced levee design and evaluate whether onsite material will be suitable for levee

expansion.


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At this time it is assumed the Phase I project will not include constructing new levees and that the existing levees along the tidal channel between Pond E8A and Pond E8 will provide adequate flood protection for areas inland of the Phase I project.

As part of this task, GeoResources will perform a preliminary investigation of the existing separation

levee between ponds E9 and E14 to evaluate the erodability of the levee. As part of this evaluation, GeoResources will collect soils samples (by hand augering) for future design analysis and recommendations.

5.4 GEOMORPHIC EVALVAnON - COMPLETE

PWA will perform a geomorphic evaluation of the conceptual plan in order to define likely scenarios for short-term and long-term site conditions in order to inform the project design. In our evaluation, PWA

will consider the following geomorphic changes with the potential to affect flood mitigation and habitat restoration:

• Pond/wetland sedimentation • Channel scour and bank erosion • Remnant slough scour / gypsum accumulation

• Breach scour • Tides within ponds

This task includes two days (two people) of field reconnaissance to assess the depth of gypsum accumulation in Pond E8A. We will sample gypsum thickness and field test in-situ shear strength to help evaluate the likelihood that remnant slough channels will scour through tidal action.

Table 2 summarizes the geomorphic scenarios that will be defined under this task and utilized in

hydrodynamic model simulations; additional runs may be necessary to assess extreme flood conditions.

Table 2 Simulation Scenarios

Simulation Timing Comments

Existing Conditions Current Existing levees and channel geometry

No Project Long-Term Includes projected sea level rise

Conceptual Plan Short-Term

Immediately after breach Existing creek channel geometry (no scour)

Existing pond geometry

Conceptual Plan Long-Term "Worst Case"

Existing Creek channel geometry (no scour) Projected marshplain sedimentation, with developed channels



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Long-term creek channel cross-sections based on hydraulic

Conceptual Plan Long-Term

"Most Likely"

geometry calculations (including scour)

Projected marshplain sedimentation, with developed channels inside the ponds

Includes projected sea level rise

5.5 HYDRODYNAMIC MODELING - COMPLETE

The MIKE Flood model developed in Task 1 will be used to model existing conditions within the OAC

and the adjacent ponds, from San Francisco Bay to 1-880. The existing conditions model will serve as a base for developing models of the Phase I project. The model will allow for comparisons between

existing and proposed conditions and between short-term and long-term conditions following restoration. Scenario modeling will be used to refine the project design to meet ecological goals including tidal

circulation and wetland development. PWA will also evaluate potential flood impacts of the restoration project for the purposes of environmental documentation.

5.6 OPINION OF PROBABLE COSTS - COMPLETE

PWA will develop conceptual-level opinion of probable construction costs for the Phase I project. PWA will use cost estimating data developed by DRS for the initial feasibility studies and data developed by

PWA and Brown and Caldwell for SBSP and the Napa River Marsh Restoration. We will also try to

obtain construction bid prices for similar construction projects from the District, Cargill, and other local

clients.

5.7 PHASE I CONCEPTUAL DESIGN - COMPLETE The results of the modeling, empirical analyses, cost estimates and other evaluations will be used to develop a conceptual design for the Phase I project. We will produce a report that summarizes the results of the analyses and describes conceptual design. PWA will submit one draft to the District for review and

respond to the District's comments in the final version.

5.8 BREACHES AND MARSH RESTORATION EARTHWORK - COMPLETE PWA will design earthwork features associated with tidal restoration including levee breaching and/or

lowering to reintroduce tidal action and blocking or filling borrow ditches. PWA will locate and size breaches and ditch blocks based on existing site conditions (e.g. vegetation, soils, hydrology),

construction feasibility and our experience with similar projects.

Based on our experience with other salt pond sites, it is likely that historic channels will scour on their

own, making extensive channel excavation unnecessary. As an exception, channels may be excavated to address gypsum accumulation in the ponds. For budgeting purposes, we have assumed that the design may include excavation of one main channel in Pond 8A to facilitate channel scour. The basis of design for marsh restoration features will rely heavily on the geomorphic assessment described above.


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5.9 LEVEE ENHANCEMENT - COMPLETE

We assume that the separation levee between Ponds E9/E8X and Pond E14 will need to be enhanced to protect managed ponds to the north. The PWA team will design enhancements to the existing levee that

meet SBSP requirements (not FEMA standards). We anticipate that enhancements will include raising the levee crest to reduce the frequency of overtopping and/or widening and/or reinforcing the levee for increased erosion resistance. Levee enhancements would be a coordinated effort of geotechnical, hydraulic and civil design.

PWA will develop a design configuration for the enhanced levee based on our flood analysis and

predictions regarding erosion potential. We anticipate the levee design will include a vegetated terrace to

dissipate wave energy, rather than armoring. GeoResources will evaluate stability and potential settlement of the enhanced levee design and evaluate whether onsite material will be suitable for levee expansion.

At this time it is assumed the Phase I project will not include constructing new levees and that the existing

levees along the tidal channel between Pond E8A and Pond E8 will provide adequate flood protection for areas inland of the Phase I project.

5.10 POND E10 LEVEE IMPROVEMENT PRELIMINARY DESIGN - COMPLETE PWA will develop the preliminary design (30%) for the Pond E10 levee improvement. PWA will

coordinate with ACWCFCD and CDFG to resolve the preferred conceptual design and habitat mitigation goals. The scope of work for the Pond ElO levee improvement is based on the understanding that the Pond E10 levee improvement will include placement of dredge material from the ACWCFCD's OAC

maintenance project on the inboard Pond E10 levee slope (pond side) as reinforcement. The purpose of the reinforcement would be to widen the levee and prolong the time over which the levee can withstand

tidal scour in Mt. Eden Creek due to restoration of Pond E9. PWA will also consider the construction of a new levee segment to realign the Pond EIO levee as a project alternative and/or future option. The

preferred conceptual design will be carried forward to preliminary and final design.

PWA will provide a written description of the Pond E10 levee improvement preliminary design suitable

for regulatory permit applications, preliminary estimates of construction quantities, preliminary design

schematics in figure format, and preliminary engineer's estimates of construction costs. ACWCFCD is responsible for the OAC maintenance/dredging project, including dredge material characterization. The

OAC maintenance project is a separate project from the Phase 1 project and Pond EIO levee

improvement.

We assume that ACWCFCD will provide the following to PWA to facilitate the Pond E10 levee

improvement design: • Quantity and quality of OAC dredged soils to be used as fill for the levee improvement, including

the soil type, condition, volume, suitability as wetland cover, and handling issues

• Mitigation needs for the OAC dredging project


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• Field surveys of the Pond El 0 levee and levee improvement area.

PWA will provide a brief Pond E 10 Levee Improvement Preliminary Design Memorandum (PDM) as an

addendum to the Phase 1 project PDM. The Pond ElO Levee Improvement PDM will include

approximately two pages of text and two figures showing the preliminary design in plan and cross

section. This task includes one meeting with ACWCFCD, CDFG, and the PMT.

5.11 30% DESIGN SUBMITTAL - COMPLETE

The project team will provide progress submittals to allow timely review and input from the District as

the design progresses. The first submittal will be an approximately 30% complete design that will

establish basic design elements and highlight project constraints.

5.12 SUBCONSULTANTS

5.12.1 EDAW: COMPLETE

The PWA team is currently preparing the South Bay Salt Pond Restoration Program EIS/EIR, which will

assess the potential environmental impacts of the long-term restoration plan on the entire SBSP project

area, including the Eden Landing pond complex. The EISIEIR will also include a more. detailed (project

level) analysis of Phase 1 projects.

The Phase 1 project identified in this Scope of Work is not among the projects included in project-level

documentation already contracted by the SBSP project. Therefore, supplementary project-level

environmental setting information and impact analysis will be needed. EDAW will develop project-level

environmental setting information and impact analysis for inclusion in the SBSP documentation.

5.12.2 HT Harvey =COMPLETE H.T. Harvey and Associates will provide review and coordination of biological and habitat elements of

permitting and funding applications, including integration with SBSP habitat elements.


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3. TASK .03B - PHASE I RESTORATION PROJECT FINAL DESIGN (REVISED SCOPE)

This section describes PWA's revised scope of work for the Ponds E8A, E9, and E8X tidal restoration final design. These changes are needed to make the design scope of work consistent with the project

implementation plan described in the April 2008 Ponds E8A, E9, and E8X Preliminary Design Report (PDR). The implementation plan includes integrating and phasing the construction of the Ponds E8A, E9

and E8X restoration with the Ponds EI2-13 restoration, with phased construction over three years.

There are benefits to linking the two projects, as compared to designing them separately. Integrating the two projects allows a more efficient coastal flood management approach, utilizing the pond levees and Pond El4 as a flood management system rather than relying on a single levee for flood protection. In addition, the beneficial use of excess earth from the Ponds E8A, E9, and E8X project for the Ponds E12E13 project is expected to eliminate the need to import material, speed implementation, and result in

construction cost savings. Linking the projects in phases also minimizes the total construction period, thereby limiting the impact on endangered species.

Under the phased approach, construction work for the integrated project will begin in Year I and end in Year 3. The Pond E8A, E9, and E8X restoration will be completed in Year 2 and the Ponds EI2-13 restoration will be completed in Year 3. The scope revisions described below add the design for Year 2 construction of the Ponds E8A, E9, and E8X restoration and Years I and 2 construction of the Ponds

El2-E13 restoration to the existing scope of work for the Ponds E8A, E9, and E8X project. (Design for Year 3 construction of the Ponds El2-E13 restoration will be accomplished under PWA's SBSP Restoration Project contract with the California State Coastal Conservancy.)

The existing scope of work includes a preliminary design submittal with preliminary drawings (approximately 30% complete), two progress submittals at the 65%- and 95%-completion levels, and a final submittal with design documents (drawings and technical specifications) suitable for public bidding.

The preliminary design is presented in the April 2008 Preliminary Design Report. PWA will provide a more detailed layout of the preliminary design on the project base map to complete the preliminary design

task.

3.13 DESIGN PHASE HYDRODYNAMIC MODELING - IN PROGRESS PWA constructed a MIKE FLOOD hydrodynamic model of the Ponds E8A, E9, and E8X Phase 1 tidal

restoration (Phase 1 project) for the EIS/R and conceptual design. PWA will update the existing hydrodynamic model for the preliminary design of the Ponds E8A, E9, and E8X restoration and perform

additional model runs for the final design.

The following restoration components changed during the course of the conceptual design: • Number, location, and size of breaches to provide tidal drainage • Pond E10 levee improvement to protect the levee from tidal scour


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PWA will update breach locations and sizes and incorporate the Pond E10 levee improvement in the model. PWA will perform three additional model simulations to address final design issues, which may include the following:

• Dry-weather run to assess: o Tidal scour of Mount Eden Creek (MEC) and the Pond E I0 levee

o Tidal drainage of Ponds E8A, E9, and E8X and the Eden Landing Ecological Reserve (ELER)

• Worst-case wet-weather run to re-confirm that the Phase I project does not adversely effect on Old Alameda Creek (OAC) flood performance.

• Alternate wet-weather run to characterize the benefits of the Phase 1 project on OAC flood performance

PWA will provide a brief Final Design Hydrodynamic Modeling Memorandum, approximately 10 pages in length including text and figures.

3.14 FINAL DESIGN SUBMITTALS - IN PROGRESS The original scope of work for the 65%, 95%, and final submittals is replaced by the scope of work below. The scope of work is modified to be consistent with the integrated, phased implementation plan.

We assume the following project phases for the purposes of this scope of work:

Year I • Earth berm between Ponds EI2 and E13 and water control in Pond E12 to allow for

Snowy Plover habitat management during construction.

• Ponds E8A, E9, and E8X levee lowering - first pass

• Pond E14 south levee improvement - first lift

• Pond E 14 north levee improvement - first lift

• Pond E10 levee realignment - first lift. Year 1 design documents for the Pond E10 levee realignment are included in the existing scope of work for Task 3.2.4.3.

Year 2 • Ponds E8A, E9, and E8X levee lowering - second pass

• Pond E 14 south levee improvement - second lift

• Pond E 14 north levee improvement - second lift

• Replace the two water control structures on the western ends of the Pond E14 north and south levees (i.e., the water control structures between Pond E9 and Pond E14 and between Pond EI4 and Pond E13). The design for these two water control structures is included in the existing scope of work for Task 3.2.2.4.

• Pond E I0 levee realignment - second lift and MEC channel widening

• MEC channel deepening (optional or additive bid item)

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• Tidal marsh ponds

• Gypsum pre-treatment

• Intemallevee breaches, connector channels, pilot channel, and ditch blocks

• Outboard levee breaches and pilot channels

• Ponds E12 and E 13 earth benns and islands - first lift

The previously contracted scope of work for this task included a single set of design documents. The scope of work is modified to include two sets of design documents: Year 1 improvements and Year 2 improvements. For each set of design documents, PWA will prepare progress submittals at the 65%- and

95%-completion levels. The progress submittals will include a refined drawing set, preliminary technical specifications and an updated engineer's estimate of likely construction quantities and costs. The final submittals will consist of signed and stamped design documents (drawings and technical specifications) that are suitable for public bidding. We will also review and comment on bid documents prepared by the District for consistency with the technical design.

The scope previously contracted for this task was based on a drawing set of 10 sheets. For budgeting purposes, we have revised the list of drawings to reflect the new design approach. Per the attached list, we currently anticipate that Year 1 and Year 2 improvements will consist of 13 and 21 sheets,

respectively. (This provisional drawing list is subject to refinement as the project progresses.)

Services by Others (Project Assumptions)

Topographic Survey. PWA anticipates that three rounds of surveying will be required prior to construction in Years 1,2 and 3 to confinn site conditions. We assume that Alameda County will perform these surveys. If needed, PWA is available to perform surveys as an additional service at the request of

Alameda County.

Bid Manual. We understand that the Alameda County will prepare all other portions ofthe bid manual in addition to drawings and technical specifications provided by PWA (e.g., Divisions 0 and 1).

Drawing List

Table 2. Year 1 Design Documents Number

Sheet Title of Sheets

Title Sheet and General Notes 1

Site Map, Access Plan, Survey Control 1

Site Plans - Ponds E9, E8A and E8X and Ponds E12-E13 4

(assumed 200' scale) Pond E12/£13 Earth Berm - Profile and Sections 1

Pond E12 Water Control Structure - Plan and Sections 1

Pond E12 Water Control Structure - Details 1


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Levee Lowering - Profile and Sections 1

Pond E14 South Levee Enhancement - Profile and Sections 1

Pond E14 North Levee Enhancement - Profile and Sections 1

Pond ElO Levee Realignment (previously contracted in Task 3.2.4.3) 1 Total Count 13

We anticipate delivering 3 complete draft sets and 5 complete final sets = Approximately 104 sheets

Table 3. Year 2 Design Documents

Number Sheet Title of Sheets Title Sheet and General Notes 1 Site Map, Access Plan, Survey Control 1 Site Plans - Ponds E9, E8A and E8X and Ponds E12-E13 4

(assumed 200' scale)

Levee Lowering - Profile and Sections 1 Pond E 14 South Levee Enhancement - Profile and Sections 1 Pond El4 North Levee Enhancement - Profile and Sections 1 Water Control Structures - Plans and Sections (previously contracted 2

in Task 3.2.4.4)

Water Control Structures - Details (previously contracted in Task 2

3.2.4.4)

Pond E 10 Levee Realignment 1 MEC Channel Deepening - Profile and Sections 1

Levee Breaches - Detail Plan and Typical Sections 2 Typical Details - Ditch Blocks and Pond E8A Channel 1 Typical Details - Tidal Marsh Ponds and Gypsum Pre-Treatment 1 Pond E12/E13 Earth Berms and Islands - Profiles and Sections 2

Total Count 21

We anticipate delivering 3 complete draft sets and 5 complete final sets = Approximately 168 sheets

Work products for this task will be project plans and specifications suitable for the District's use in

bidding the Phase I project construction. Expenses for this task include an allowance for

reproduction. Additional plan sets can be provided as an add-on task.

3.15 DESIGN TEAM INTEGRATION - NEW TASK

PWA will work closely with our geotechnical and civil engineering subconsultants as well as District

design staff and the District-selected construction management firm to integrate all aspects of the project

design and specifications, and support the construction bidding process. Due to circumstances beyond our

control, we have replaced both the geotechnical and civil engineering subconsultants on the project team

during the transition from preliminary design to final design development. This task will cover the time

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required for PWA to bring the new consultants up to speed on the project, including meetings and site

visits as needed.

3.16 TIDAL MONITORING AT EDEN LANDING- NEW TASK

PWA will conduct tide monitoring at Eden Landing in support of the restoration design development.

3.17 SUBCONSULTANTS

3.17.1 Brown & Caldwell =COMPLETE B&C will provide Civil Engineering support and supplementary project-level environmental documentation for the Phase I restoration project. B&C will also provide Civil Engineering support for

Phase I preliminary design development.

3.17.2 GeoResources =COMPLETE GeoResources will provide geotechnical support for Phase I preliminary design development.

3.17.3 Noble consultants =NEW SUBCONSULTANT Noble Consultants will be added to the project team to provide civil engineering services in support of the Phase I Restoration Final Design.

3.17.4 Geomatrix =NEW SUBCONSULTANT Noble Consultants will be added to the project team to provide geotechnical engineering services in

support of the Phase I Restoration Final Design.


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4. TASK .04 - LAGUNA CREEKILAKE ELIZABETH

Lake Elizabeth provides a critical flood management function in controlling high flows in the

IMissionJLaguna Creek system in Fremont. Mission Creek, initiating in the watershed below Mission

jPeak, flows northward towards Lake Elizabeth, then westward from the Lake, joining the San Francisco

iBay through the salt pond complex. Upstream of the lake, the stream is referred to as Mission Creek;

Idownstream of the lake, it is referred to as Laguna Creek.

PWA will work with the District to develop a management plan for Lake Elizabeth, based on

hydrodynamic modeling performed by others. The goal of the management plan is to optimize flood

hazard reduction while meeting recreational requirements at Lake Elizabeth. Similarly, we will work with

the district to define a preferred alternative for connecting Laguna Creek to the SBSP, and coordinate

with the SBSP process to incorporate the identified alternative into the SBSP planning process.

4.1 LAKE ELIZABETH MANAGEMENT PLAN - IN PROGRESS

PWA will use the results of the hydrodynamic model (by others) to identify a recommended management

strategy for Lake Elizabeth that integrates the flood management elements of the system should with any

recreational and wildlife/wetland objectives identified by the District. We will then work closely with

District staff to finalize a lake management strategy that will establish guidelines for the District's license

agreement with the City of Fremont. Work products for this task will be a draft and final

memorandum documenting recommendations for the Lake Elizabeth Management Plan.

4.2 LAGUNA CREEK PROJECT - IN PROGRESS

PWA will work with the District to identify a preferred alternative for the Laguna Creek connection with

the adjacent salt ponds, based on results of hydrodynamic modeling (by others) and coordination with

SBSP. PWA will develop conceptual design drawings (approximately 10% design) for the preferred

alternative. Work products for this task will be a draft and final memorandum summarizing the

Laguna Creek conceptual design.


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5. TASK .05 - PROJECT MANAGEMENT & COORDINATION

The PWA Project Manager and appropriate Team Leaders will conduct regular progress calls with

subconsultant staff. The progress calls will provide an opportunity to discuss progress on active tasks and

deliverables; identify any necessary changes to the project approach and schedule; discuss and resolve

key issues; and identify items for follow-up. The PWA Project Manager will keep notes of topics

discussed, decisions, and action items. These notes will be filed in the PWA project file.

The PWA Project Manager conducts detailed project tracking once per month during preparation of the

monthly invoice. The tracking process includes comparing actual monthly expenditures to expected expenditures and remaining budget, at a sub-task and subcontractor level of detail. The expected

expenditures are based on sub-task start and end dates and percent complete. Any significant deviations from expected progress are identified and acted upon as appropriate. Brief written progress updates will

be provided to the client with each monthly invoice. Each invoice will describe progress by task and

include a summary table of dollars expended to date, total budget, and budget remaining.

The PWA Project Manager will be responsible for ongoing client communications and coordination. We

anticipate developing a regular schedule of meetings with District staff, to include the PWA project manager, relevant Team Leaders and/or subconsultant staff, to provide progress updates, identify any

necessary changes to the project approach and schedule; and discuss and resolve key issues.

5.1 PROJECT MANAGEMENT AND COORDINATION - IN PROGRESS

The consultant team will work closely with District staff to clarify project objectives, refine the scope of

work if needed, identify project deliverables, and agree upon project deadlines throughout the project,

ensuring that our efforts are consistently focused on the District's highest priorities. This process will be

initiated with a project kick-off meeting, followed up by monthly project meetings between the PWA

project manager, the District project manager, and subconsultants, other District or Agency staff, and others as needed.

5.2 COORDINATION WITH OTHER PROJECTS & AGENCIES - COMPLETE

PWA will coordinate and provide integration with other projects affecting the project area, including

SBSP and the Corps Shoreline Study. As part of this effort, H.T. Harvey and Associates will provide

review and coordination of biological and habitat elements, including integration with SBSP habitat elements. PWA will also coordinate with the proposed re-mapping effort for San Francisco Bay for FEMA. PWA wrote the scope of work for re-mapping the South Bay, and also participated in developing the FEMA Guidelines for Coastal Flood Hazard Analysis and Mapping.

The level of effort anticipated in the original contract has been completed. Ongoing coordination will be

accomplished through the PWA Project Manager under the Project Management and Coordination task.


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5.3 TECHNICAL SUPPORT FOR CORPS SHORELINE STUDY - IN PROGRESS The Corps and two non-Federal sponsors, the California State Coastal Conservancy and Santa Clara Valley Water District, have prepared a near-final draft of the South San Francisco Bay Shoreline Study Project Management Plan (PMP). PWA has been intimately involved in this effort. We prepared scopes of work and cost estimates, and served in a coordination role. PWA will provide support to the District for the Shoreline Study by attending monthly coordination meetings, as needed, and providing technical support.

5.4 EOA - IN PROGRESS EOA will facilitate Lower Alameda Creek Stewardship Committee meetings in coordination with District staff. Preparation and distribution of agendas, chairing meetings, preparation of meeting minutes is anticipated for this task. This scope of work includes facilitation services for up to fifteen meetings over the course of the contract. The Project team will also make periodic presentations to this committee.


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6. TASK .06 - EXPENSES (COMPLETE)

Expenses include reimbursable PWA expenses associated with Tasks described above, as well as vendor services requested by the District. Expenses anticipated under the original contract have been expended. Any expenses related to on-going tasks will be applied to the relevant task under the modified contract.

6.1 PWA REIMBURSABLE EXPENSES - COMPLETE This task covers PWA reimbursable expenses.

6.2 WATERSHED SCIENCES - COMPLETE Watershed Sciences will provide data and information related to Eden Canyon sedimentation to support PWA's Task 6. Total amount not to exceed $500.

6.3 STORESUND CONSULTING - COMPLETE Storesund Consulting will provide terrestrial LiDAR scanning services to map sediment deposits in the vicinity of the Sunol Dam removal site. Total amount not to exceed $5,000.

6.4 TOWilL INC. - COMPLETE Towill Inc will provide land surveying services for the Eden Landing area. Total amount not to exceed $3,456.


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7. TASK NUMBER NOT USED










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16. TASK .16 - DUBLIN GEOMORPIDC MONITORING

This task includes geomorphic monitoring on Marshall and Hollis Creeks downstream of the Schaefer

Ranch project site in Dublin, California. Following on a Memorandum of Agreement between Discovery

Builders, Inc. and the Alameda County Flood Control District, the two parties have agreed to retain

geomorphologic services to monitor creek stability downstream of the project site. PWA's scope of work

provides an initial geomorphic reconnaissance of the project site to assess overall potential erosion

problem areas and possible opportunities to minimize erosion and excess runoff to prevent off-site

problems. It then outlines steps to establish baseline stream cross-sections and longitudinal profiles in the

stream channels, monitor the channels and evaluate changes in stream geometry over the next five years.

The detailed scope ofwork is provided below.

16.1 PROJECT INITIAnON - COMPLETE

We will meet with the Alameda County Flood Control District (District) staff and other stakeholders as

appropriate to discuss the project scope, schedule and deliverables. We will review, obtain and review

background documentation for the project, specifically the Mitigation Monitoring Plan, the Stormwater

Pollution Prevention Plan and the Plan of Control for the Geological Hazard Abatement District. These

plans will form the baseline by which compliance will be measured. A key element of the base data will

be to obtain a usable site map for location of key project elements, the stream channel cross sections and local survey benchmarks.

16.2 SITE RECONNAISSANCEIESTABLISH MONITORING PROGRAM - COMPLETE

After reView of the pertinent documentation we will conduct a site reconnaissance to identifY existing site

erosion conditions, and identifY potential opportunities to control erosion generation or trap sediment on

site. We will then develop a monitoring program to assess changes in sedimentation or erosion in the

stream channels which drain the site.. We will perform our initial site reconnaissance and establish cross

section locations, and we will develop a plan for evaluating changes in channel cross sections for the next

five years. We will deliver a brief memo on the site conditions, initial opportunities, and the proposed

monitoring program and present the steps and schedule necessary to complete the project.

16.3 ANNUAL MONITORING AND REPORTING - IN PROGRESS

We will initially survey cross-sections at the study reaches to establish baseline, or "Year Zero"

geometries. We will also document the channel at our cross-section locations through photographs and

detailed field notes, which will be made available to the District. Then the cross-section locations will be

resurveyed during years 1,2, 3, and 5 to compare sedimentation or erosion during the monitoring period.

After each year of monitoring, we will prepare a brief report describing any changes that have been observed along with the cross-section data.

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17. TASK .17 - EDEN LANDING LEVEE DESIGN DEVELOPMENT (COMPLETE)

This task provides for engineering review ofthe EBRPD design for the Bay Trail and ELER, pertaining to

modification of an existing levee and its flood control function. The review evaluates the levee for its

confonnance with the anticipated future design and construction schedule for the Eden Landing flood

control levee. The FEMA-designated floodplain extends landward of the levee and includes developed

areas. The Alameda County Flood Control and Water Conservation District (ACFCWCD) is interested in

revising the EBRPD trail design to be consistent with a new flood control levee expected to be

constructed in the future.

17.1 INITIAL ASSESSMENT - COMPLETE

PWA, under contract to ACFCWCD, provided independent civil engineering review of the EBRPD Bay

Trail construction documents. PWA reviewed the ELER engineering studies and construction documents.

PWA attended meetings and coordinated directly with EBRPD to obtain project documents for the trail and the ELER. PWA assessed elevation data for the trail; geotechnical design data; interior drainage; and

levee operation and maintenance plans. PWA compared the trail design to existing San Francisco Bay

water levels at Eden Landing. We discussed stonn surge, tidal dynamics, and extreme Bay water levels.

We also commented on the potential flood impacts associated with the ELER or EBRPD projects. PWA

provided suggestions for revising the EBRPD Bay Trail design, as it pertains to flood protection.

The SBSP Project is dedicated to providing a consistent level of flood hazard management with flood

protection measures (levees, high ground) meeting both FEMA and US Anny Corps of Engineers

(USACE) criteria. PWA provided coordination with the SBSP project key stakeholders so that the

objectives of the ACFCWCD are consistent with the SBSP flood management program for Eden Landing.

We tracked SBSP Project updates of the conceptual design for the perimeter flood control levee. PWA

monitored the SF Bay levee design recommendation from USACE and FEMA, as they become available.

17.2 PRELIMINARY DESIGN - COMPLETE

The scope of work included our coordination with the geotechnical engineer, GeolResource. PWA met

with GeolResource staff and discuss the project objectives. PWA provided reports and data for their

initial assessment of the conditions at Eden Landing. GeolResource gathered geotechnical data to support

their continued work in future tasks. They reviewed design documents provided by EBDA. GeolResource

did not provide review and recommendations on the EBRPD levee since it has was detennined that no

geotechnical studies for the Bay Trail levee exist. However, infonnation provided by GeolResource did

infonn PWA's recommendations.

PWA perfonned a site reconnaissance of the proposed levee alignment; initiated preparation of base mapping for design development; and developed the scope of work for the Eden Landing Flood Control

Levee Preliminary Design.

Deliverables


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PWA reported our findings in a memo entitled: "Eden Landing Flood Control Levee & Bay Trail Coordination." The memo combines what we know about the EBRPD project, the CDF&G ELER Project

and the SBSP project, with tidal datum and extreme water levels data to inform our discussions with

EBRPD & CDF&G. We intentionally omitted any specific comments on the potential flood impacts

associated with the ELER or EBRPD projects. We first met with EBRPD & CDF&G to confirm our

research.

PWA attended meetings with ACFCWCD, EBRPD, EBDA and GeolResource. PWA prepared minutes

for the EBRPD and EBDA meetings for ACFCWCD.


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18. TASK .18 - SFEI ALAMEDA CREEK SEDIMENT

18.1 PWA OVERSITE OF SFEI SEDIMENT STUDY - COMPLETE

PWA will provide oversight and input to the tasks described in the SFEI scope of work.

18.2 SFEI ALAMEDA CREEK SEDIMENT STUDY - COMPLETE

SFEI's scope ofwork for this task is unchanged.

18.3 SFEI ALAMEDA CREEK SEDIMENT FORUM - NEW TASK

SFEI will organize and facilitate an "Alameda Creek Sediment Forum". SFEI will organize venues,

prepare agendas, organize speakers, facilitate the meetings, and provide meeting materials back to the

delegates via the forum web page (http://www.sfei.org/alamedacreek/forum.html). Invited meeting

delegates should include all delegates who participated in the April and December 2008 forums, those

who have registered through the forum web page, all parties who sponsored the "Alameda Creek

Watershed Management Program poster", and a CALTRANs representative. Meeting topics will depend

on stakeholder needs, current management questions, and the mix of recent completed water and sediment

related projects.

18.4 SFEI DATA SUPPORT FOR AND REVIEW OF SEDIMENT TRANSPORT MODEL - NEW

TASK SFEI will support the ongoing development of ID/2D modeling in the Alameda Creek Flood Control

Channel. Support will include:

a) Provision of Water Year 2007 and 2008 15 minute data (2008 data likely available in April 2009).

b) Field study design and collection of a grain size data set in the Flood Control Channel between the tidal limit near Ardenwood Blvd and Decoto Road or further upstream if appropriate based on the boundary conditions of the 2D modeling. Design will occur in consultation with project staff to ensure the data is collected with an appropriate technical compromise between all influencing factors (2D model architecture; spatial grain size variations in the cross section, vertically, and longitudinally; patch variation between geomorphic channel features; tributaries influences). Data will be summarized in a short technical memo and provided in digital form to the ACFC&WCD PROJECT MANAGMER. The methods section of the technical memo will be written clearly so that sample collection and laboratory analysis specifications can be repeated by Alameda County Public Works Laboratory staff.

c) 2D model review. SFEI will receive a copy of the final draft report associated with the 2D model of the Flood Control channel and provide a written colleague review referring to page numbers or section numbers to the ACFC&WCD PROJECT MANAGMER.


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18.5 SFEI DRY CREEK RECONNAISSANCE - NEW TASK

SFEI will carry out a reconnaissance study of Dry Creek in Union City to support recommendations on

future sediment source analysis or sediment monitoring needs. Existing known historic data includes

USGS landslide and debris flow identification after the February 2-3 1998 storm and USGS flow data

(1916-present). Subtasks include:

a) SFEI shall conduct a preliminary «4 hour search) for other documents specifically relating to water flow, geomorphic processes and sediment loads from agencies including US Army Corps, USGS, Union City, Alameda County, and ACFC&WCD and East Bay Regional Parks District. SFEI shall archive copies and provide a list to the ACFC&WCD PROJECT MANAGMER.

b) SFEI shall perform a preliminary review of aerial imagery to support the design and implementation of reconnaissance fieldwork, the outcome of which will be a preliminary assessment of sub-watershed scale sediment sources.

c) SFEI shall use existing local and regional data to make preliminary estimates of suspended and bed loads on an annual time basis and describe the level of uncertainty in such estimates.

d) CONTRACTOR shall provide a technical memo « 10 pages) that will describe uncertainties in current knowledge on the topic of sediment supply from Dry Creek to mainstem Alameda creek, a comment on a bar located within mainstem Alameda at the confluence, a comparison to the total sediment load at Niles, and recommendations on future source analysis or monitoring needs.

18.6 SFEI SPARTlNA MANAGEMENT PLAN - NEW TASK

SFEI shall produce a scientifically sound plan for surveillance of tidal marsh in Eden Landing for

invasive Spartina re-infestation, so that measures can be taken before it becomes an extensive problem

again. The monitoring plan will include partnering between agencies and will seek to keep Spartina

monitoring to a feasible budget. Weed control protocols will not be included in the SOW, because control

measures developed by the ISP will be more efficiently communicated by the ISP rather than by SFEI. However, additional weed monitoring of other invasive species will be included in the plan. The

geographic scope is the Eden Landing DFG lands (South Bay Salt Pond Restoration Project Phase I tidal

restoration area in Eden Landing, Eden Landing Ecological Reserve Restoration Project, Old Alameda

Creek, Whale's Tail and shoreline strip marshes, and the Cargill Mitigation Marsh), and the focus of monitoring is on tidal marshes, both extant marshes and the nascent marshes in restored salt ponds. SFEI

shall complete the following sub-tasks:

a) Invasive Spartina monitoring plan • Provide a range of definitions and methods for detecting Spartina that should be eradicated. For

example: invasive Spartina as identified by ecotype (growing very low or very high in the tidal range), by phenotype (very tall and clumped with large inflorescences), by genotype using RAPDs (best available genetic tool), or by genotype using microsatellites (tool in development).

• Develop a surveillance protocol for invasive Spartina using aerial or satellite imagery and field data collection and incorporating the range of invasive Spartina detection techniques above.

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• Layout a process for a group of stakeholders and scientists to decide on thresholds (from the range of definitions and detection methods above) that would trigger control actions.

• Participate in a collaborative process with ISP and partner agencies to ensure that the surveillance monitoring can be easily coordinated with control measures ISP has developed.

•

b) Monitoring plan for other weeds • Develop a list of the invasive species of concern in conjunction with DFG.

• Develop a surveillance protocol using aerial or satellite imagery and field data collection.

• Participate in a collaborative process with ISP and partner agencies to ensure that the surveillance monitoring can be easily coordinated with control measures ISP has developed, if these measures are relevant for the control of species other than Spar/ina.

c) Data management plan • Determine where the data will be managed and stored.

• Determine appropriate data management strategy and format.

• Consider if the State Water Quality Control Board will require inclusion in the SWAMP Data Center.

•

d) Cost estimation • Provide cost estimates for monitoring and data management, when possible.

•

e) Coordination with partner agencies • Coordinate and vet monitoring plan with key organizations

c South Bay Salt Pond Restoration Project c California Department of Fish and Game c Alameda County Flood Control District c Alameda County Mosquito Abatement District c Invasive Spartina Project c Regional Water Quality Control Board c East Bay Regional Park District (Bay Trail) c Don Edwards SF Bay National Wildlife Refuge c State Water Quality Control Board


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19. TASK .19 - DID ALAMEDA CREEK MODELING

19.1 PWA OVERSITE OF DRI MODELING - COMPLETE IPWA will provide oversight and input to the tasks described in the DID scope of work.

19.2 DRI MODELING OF ALAMEDA CREEK - COMPLETE DRI's scope of work for this task is unchanged.

19.3 ADDITIONAL DRI MODELING OF ALAMEDA CREEK - NEW TASK

DRI will undertake morphological modeling of Alameda Creek under this additional task.

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20. TASK .20 - JOINT PROBABILITY FLOOD ANALYSIS (NEW TASK)

Water levels in streams and stonn drains near San Francisco Bay are subject both fluvial and tidal influences. The prediction of design water levels (or hydraulic head) in these areas requires consideration be given to the relative magnitude of both fluvial and tidal water levels and the interaction between them. In coastal areas, three regimes of water level control may occur:

1. In the upstream reaches ofstreams and culverts, water levellhydraulic grade line is controlled entirely by fluvial factors (rainfall runoff and channel/pipe parameters).

2. Along the bay shoreline, water levels are controlled almost entirely by tidal factors (astronomical tide, combined with stonn surge and wave effects).

3. In stream and culvert reaches that are located between these two zones, a transition zone exists in which water levels reflect a proportional influence of both fluvial and tidal factors.

This study will focus on developing methods to assist in characterizing the hydrologic conditions in regime #3 above. In particular, it addresses the question of determining an appropriate downstream water surface elevation (at the Bay interface) for hydraulic modeling of flow in open channels or culverts that are subject to tidal influence. Hydraulic modeling of a stream reach requires either the specification of downstream starting water level, or a calculation to estimate this level. Once this boundary condition is identified, the models use a combination of the design channel/culvert flow rates as model input, and the physical parameters of the stream channel/culverts (cross-sectional characteristics, slope, roughness etc) to compute the resulting water surface along the system. Typical programs such as HEC-RAS use a step-backwater computational procedure to accomplish this, beginning with a given downstream water surface elevation.

From a statistical perspective, the task consists of assessing the joint likelihood of the occurrence of the two random variables (rainfall-runoff rates and associated tidal levels). This problem would be relatively simple if these random variables were independent (that is, the likelihood of large rainstonns was independent of the likelihood of higher than predicted (astronomical) tides. However, practical experience has shown that they are not: extreme periods of rainfall often occur during periods of higher than predicted bay tides. Traditionally, FEMA criteria have specified the use of Mean Higher High Water (MHHW) level in the bay as the starting water surface for modeling fluvial flood events. However, historical observations suggest that this may not be sufficiently conservative.

This study is designed to identify the relationship between flood-producing rainstonns or stream flow, and concurrent tide levels in the bay, and assist the county in selecting appropriate guidelines for inclusion in the County Hydrology manual.


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20.1 PROJECT INITIATION PWA will meet with county staff to review the proposed methodology and work products. We will discuss with staff the availability of data to be used in the subsequent analysis. We are assuming that the appropriate data on precipitation and streamflow will be available from County data records. (we will obtain tidal data separately).

20.2 HYDROLOGIC DATA COLLECTION AND ANALYSIS We will obtain and analyze available rainfall data (as well as some flow data) to identify the major flood producing storms where concurrent tide gage records are available. We will analyze rainfall data to identify those dates when significant, flood-producing rainfall events occurred. We plan to look at perhaps one or two key, long-term rainfall stations in the county. In addition, we will review the flow records for the gaging stations on the 4-creeks in the county to aid in the identification of the major floods events. These include gages on: Alameda Ck, San Lorenzo Ck, Dry Creek and Castro Valley Ck. We will obtain guidance from county staff and other records to further assist in determining major storm events.

The intent of this portion of the analysis is to: I. identify the dates of flood-producing storms, for subsequent joint assessment of tidal

conditions. 2. as feasible, characterize other parameters of the storms such as recurrence interval and

duration.

We will not be conducting detailed "Depth-Duration-Frequency analyses of the rainfall data, or complete "magnitude-frequency" assessments of streamflow data. Rather, we hope to build on the results of prior flood and rainfall studies for this information, and to supplement it with some additional review of the records as needed. The goal is to identify a range of flood events of different magnitude and duration.

20.3 BAY WATER LEVEL DATA COLLECTION AND ANALYSIS For the dates of significant storms identified in Tasks 2 and 3, we will collect data on concurrent bay tidal conditions. We will use the data from the Presidio Tide Gage, which is the primary, long-term gage, located at the mouth of the Bay near the Golden Gate Bridge. Since the goal of the study is to understand tidal conditions for systems along Alameda County, the Presidio data will be adjusted to reflect conditions at appropriate locations inside the Bay. This will be done using relationships based on concurrent data collected at various shorter-term gages located inside the Bay, and the Presidio station. (it is possible that for some of the storms, actual measured inner-bay data may be available, and this would be preferentially used).


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In addition to the measured tide on storm dates, we will also obtain data on the predicted tide for those days (based on astronomical conditions).

20.4 JOINT PROBABILITY ANALYSIS The data on bay tides for storm events will be simplified from actual water surface elevations to a number (or series of numbers) that characterize the difference between the observed water surface elevation and the predicted tide. This difference ("delta") is generally expected to be positive during major stonns, and should reflect the "stonn surge" component of the flood event: additional water surface elevation resulting from low barometric pressure, on-shore winds etc.

Based on the level of data available, the bay tide delta can be compared with a number of flood parameters: • Is the delta different from zero on days with floods • What is the average delta for all days with major stonns • Is the delta correlated with flood magnitude • Is the delta different for storm events of varying duration.

20.5 JOINT PROBABILITY CRITERIA The data analysis conducted in Task 5 will provide the basis for the development of guidance on the selection of a downstream (Bay) water surface in conducting hydraulic modeling of streams and culverts located near the bay. We will provide input to the County on whether to modify the existing criteria. We envision 2 different types of hydraulic modeling analysis:

1. Hydraulic modeling of a fixed (peak) flow rate: (steady-state conditions): In "fixed" flow rate analysis, a single flood flow (usually, 25- to 1DO-year) is typically routed using a 1dimensional pipe flow or river channel hydraulic model. Since this is a steady state analysis, a single, fixed downstream water surface boundary condition is selected. At present, the County uses the following criteria:

a. For a 5-yr stonn, the Bay is assumed to be at a 1DO-year tidal elevation b. For storms greater than the 5-yr event, the Bay is assumed to be at MHHW

(FEMA criteria) Based on the results of this analysis, we may recommend modifying the criteria "b" above to add an increment to account for storm surge effects. One possibility is that the increment would reflect the difference between predicted and observed HHW on days with storms.

2. Hydraulic modeling ofa time-varying flow rate: (unsteady-flow conditions): In "timevarying" flow analysis, the water surface elevation resulting from the hydrograph in the stream or culvert over time is modeled. In this case, a time-varying boundary condition is also required. We would review the bay water level data to recommend a continuous tide water level for storm conditions. As per the discussion above, this might be done by

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estimating "deltas" between the four major tidal datums: MHHW, MLLW, MHW and MLW.

20.6 DRAFT AND FINAL TECHNICAL MEMORANDUM The results of the study would be presented in a brief memo that documents the data used, analysis techniques and results, and the recommendations. An initial draft of the memo would be prepared and submitted for comment by the County. Based on this input, the memo would be revised into final form and submitted to the county.


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21. TASK.21-FEMA TECHNICAL ASSISTANCE (NEW TASK)

PWA will develop an approach to estimate the required levee crest elevation at Eden Landing, pending release of the FEMA preliminary re-mapping results. The approach will be consistent with FEMA's coastal guidelines and include interpretation of the guidelines for the Eden Landing area. An administrative draft, draft for circulation and final document will be provided. Ideally, PWA would have the benefit of reviewing the methodology that FEMA is using in their central Bay flood study, in order to

avoid non-essential differences in methods and focus on those necessary for the local conditions.

PWA will also provide technical assistance related to FEMA guidelines and re-mapping on an as-needed basis, including meetings, communications, research of methods, review of FEMA documents, etc. within

the available budget.


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