December 2015

Final Report

Documentation

West Sacramento Project General Reevaluation Report

Cover Photo: Sacramento River, West Sacramento, and Yolo Bypass, March 2011

Photo courtesy of Chris Austin.

WEST SACRAMENTO PROJECT, CALIFORNIA

GENERAL REEVALUATION REPORT

Final Report Documentation

U.S. Army Corps of Engineers

Sacramento District

December 2015

This page intentionally left blank.

Contents

West Sacramento Project i December 2015

WEST SACRAMENTO PROJECT, CALIFORNIA

GENERAL REEVALUATION REPORT

TABLE OF CONTENTS

POST-AUTHORIZATION CHANGE REPORT .................................................................................... PAC-1

1. INTRODUCTION ........................................................................................................................ PAC-1

2. DESCRIPTION OF AUTHORIZED PROJECT ................................................................................. PAC-1

3. AUTHORIZATION ..................................................................................................................... PAC-4

4. FUNDING SINCE AUTHORIZATION ........................................................................................... PAC-4

5. CHANGES IN SCOPE OF AUTHORIZED PROJECT ....................................................................... PAC-6

6. CHANGES IN PROJECT PURPOSE .............................................................................................. PAC-7

7. CHANGES IN LOCAL COOPERATION REQUIREMENTS .............................................................. PAC-7

8. CHANGE IN LOCATION OF PROJECT ......................................................................................... PAC-7

9. DESIGN CHANGES .................................................................................................................... PAC-7

10. CHANGES IN TOTAL PROJECT FIRST COSTS .............................................................................. PAC-8

11. CHANGES IN PROJECT BENEFITS ............................................................................................. PAC-8

12. BENEFIT-COST RATIO ............................................................................................................... PAC-9

13. CHANGES IN COST ALLOCATION .............................................................................................. PAC-9

14. CHANGES IN COST APPORTIONMENT...................................................................................... PAC-9

15. ENVIRONMENTAL CONSIDERATIONS IN RECOMMENDED CHANGES ................................... PAC-11

16. PUBLIC INVOLVEMENT ........................................................................................................... PAC-14

17. HISTORY OF PROJECT ............................................................................................................ PAC-15

CHAPTER 1 – STUDY INFORMATION................................................................................................. 1-1

1.1 PURPOSE AND SCOPE ................................................................................................................... 1-1

1.2 STUDY AUTHORITY ........................................................................................................................ 1-1

1.3 LOCATION AND DESCRIPTION OF THE STUDY AREA ..................................................................... 1-3

1.4 BACKGROUND AND PROJECT HISTORY ......................................................................................... 1-9

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1.5 WATERSHED PLANNING .............................................................................................................. 1-16

1.6 PLANNING PROCESS AND REPORT ORGANIZATION ................................................................... 1-24

CHAPTER 2 – PROBLEM IDENTIFICATION.......................................................................................... 2-1

2.1 NATIONAL OBJECTIVE ................................................................................................................... 2-1

2.2 PUBLIC CONCERNS ....................................................................................................................... 2-1

2.3 PROBLEMS .................................................................................................................................... 2-2

2.4 PLANNING OPPORTUNITIES ........................................................................................................ 2-21

2.5 PLANNING OBJECTIVES ............................................................................................................... 2-21

2.7 PLANNING CONSTRAINTS ........................................................................................................... 2-22

2.8 LOCAL CONCERNS ....................................................................................................................... 2-22

2.9 FUTURE WITHOUT-PROJECT CONDITION ................................................................................... 2-22

CHAPTER 3 – ALTERNATIVES ............................................................................................................ 3-1

3.1 PLAN FORMULATION RATIONALE ................................................................................................. 3-1

3.2 MANAGEMENT MEASURES ........................................................................................................... 3-1

3.3 MEASURES TO REDUCE FLOOD STAGES ....................................................................................... 3-1

3.4 MEASURES TO REDUCE LEVEE SEEPAGE AND UNDERSEEPAGE ................................................... 3-7

3.5 MEASURES TO ADDRESS LEVEE STABILITY .................................................................................... 3-9

3.6 MEASURES TO ADDRESS EROSION ............................................................................................. 3-10

3.7 MEASURES TO ADDRESS LEVEE HEIGHT ..................................................................................... 3-10

3.8 MEASURES TO ADDRESS VEGETATION AND ENCROACHMENTS ................................................ 3-10

3.9 NON-STRUCTURAL MEASURES ................................................................................................... 3-11

3.10 PRELIMINARY SCREENING OF MEASURES .................................................................................. 3-13

3.11 PLAN FORMULATION STRATEGIES .............................................................................................. 3-18

3.12 PRELIMINARY ARRAY OF ALTERNATIVES .................................................................................... 3-20

3.13 SCREENING OF PRELIMINARY ARRAY OF ALTERNATIVES ........................................................... 3-34

West Sacramento Project iii December 2015

3.14 FINAL ARRAY OF ALTERNATIVES ................................................................................................. 3-42

3.15 EVALUATION OF FINAL ARRAY OF ALTERNATIVES ...................................................................... 3-59

3.16 COMPARISON OF FINAL ARRAY OF ALTERNATIVES .................................................................... 3-59

3.17 EXECUTIVE ORDER (EO) 11988 ................................................................................................... 3-64

3.18 SYSTEM OF ACCOUNTS ANALYSIS AND COMPARISON ............................................................... 3-64

3.19 PERFORMANCE OF FINAL ARRAY OF ALTERNATIVES…………………………………………………………….. 3-68

3.20 THE RECOMMENDED PLAN......................................................................................................... 3-70

CHAPTER 4 – RECOMMENDED PLAN ................................................................................................ 4-1

4.1 FEATURES AND DESCRIPTION OF THE RECOMMENDED PLAN ..................................................... 4-1

4.2 DESIGN AND CONSTRUCTION CONSIDERATIONS ....................................................................... 4-10

4.3 ENVIRONMENTAL EFFECTS AND MITIGATION MEASURES ......................................................... 4-12

4.4 REAL ESTATE REQUIREMENTS .................................................................................................... 4-13

4.5 OMRR&R CONSIDERATIONS ....................................................................................................... 4-14

4.6 SAFETY ASSURANCE REVIEW ...................................................................................................... 4-17

4.7 RESIDUAL RISK ............................................................................................................................ 4-17

4.8 FLOOD WARNING AND EVACUATION PLANS ............................................................................. 4-21

4.9 HYDRAULIC IMPACT EVALUATION .............................................................................................. 4-25

4.10 ENVIRONMENTAL SUMMARY ..................................................................................................... 4-26

4.11 EO 11988 ..................................................................................................................................... 4-30

4.12 ENVIRONMENTAL OPERATING PRINCIPLES ................................................................................ 4-34

4.13 CAMPAIGN PLAN ......................................................................................................................... 4-35

4.14 REFINEMENTS TO PLAN ECONOMICS, ESTIMATED COST, AND COST SHARING ........................ 4-37

4.15 VIEWS OF NON-FEDERAL SPONSOR AND OTHER AGENCIES ...................................................... 4-41

4.16 POTENTIAL ADDITIONAL STUDIES ............................................................................................... 4-41

West Sacramento Project iv December 2015

CHAPTER 5 – CHANGES TO WEST SACRAMENTO PROJECT ................................................................ 5-1

5.1 CONSTRUCTED WEST SACRAMENTO FEATURES .......................................................................... 5-1

5.2 FEATURES OF THE RECOMMENDED PLAN .................................................................................... 5-1

5.3 ECONOMIC SUMMARY ................................................................................................................. 5-2

5.4 CREDIT PROVISIONS ...................................................................................................................... 5-3

5.5 COST APPORTIONMENT ................................................................................................................ 5-4

5.6 COST ESTIMATE OF THE CONSTRUCTED AND NONCONSTRUCTED PARTS

OF THE TENTATIVELY SELECTED PLAN ......................................................................................... 5-6

5.7 INSTITUTIONAL REQUIREMENTS .................................................................................................. 5-6

CHAPTER 6 – PUBLIC INVOLVEMENT, REVIEW, AND CONSULTATION ................................................ 6-1

6.1 PUBLIC INVOLVEMENT PROGRAM................................................................................................ 6-1

6.2 PUBLIC FEEDBACK ......................................................................................................................... 6-1

6.3 OTHER PUBLIC INVOLVEMENT ...................................................................................................... 6-2

6.4 INSTITUTIONAL INVOLVEMENT .................................................................................................... 6-3

6.6 ADDITIONAL REQUIRED COORDINATION ..................................................................................... 6-3

6.7 PUBLIC VIEWS AND RESPONSES ................................................................................................... 6-3

6.8 IMPACT ON RECOMMENDATIONS ................................................................................................ 6-4

CHAPTER 7 – RECOMMENDATIONS ................................................................................................. 7-1

CHAPTER 8 – REFERENCES ............................................................................................................... 8-1

West Sacramento Project v December 2015

LIST OF APPENDICES

A. Plan Formulation A.1 American River Common Features and West Sacramento General Reevaluation Reports

Bridging Document

B. Review Documentation

B.1 DQC

B.2 ATR

Agency Technical Review Report Completion of Agency Technical Review Certification of Agency Technical Review

B.3 IEPR

C. Engineering Attachment A - Hydrology Executive Report Attachment B - Hydraulic Appendix Executive Report Attachment C - Geotechnical Report Attachment D – Cost Engineering

D. Real Estate

E. Economics

West Sacramento Project vi December 2015

LIST OF TABLES

Table 1 West Sacramento Project Work Sites and Status ............................................................ PAC-5

Table 2 History of Federal Funding............................................................................................... PAC-5

Table 3 Constructed Features in West Sacramento ..................................................................... PAC-6

Table 4 Project First Cost ($000) .................................................................................................. PAC-8

Table 5 Economic Summary ($000) .............................................................................................. PAC-9

Table 6 Cost Apportionment ($000) ........................................................................................... PAC-10

Table 7 Summary of Environmental Effects and Mitigation Measures ...................................... PAC-11

Table 1-1: Authorized Project Features. .............................................................................................. 1-13

Table 1-2: Economic Summary of the Authorized Plan ($000) ............................................................ 1-15

Table 1-3: Authorized Plan Cost Apportionment ($000) ..................................................................... 1-15

Table 1-4: Section 408 (Early implementation Projects) ..................................................................... 1-19

Table 2-1: 200-Year Flood Plain Area .................................................................................................... 2-4

Table 2-2: Design Flows and Flood Flows in the Project Areas ............................................................. 2-6

Table 2-3: Life Safety and Life Loss Information (from USACE’s Levee Screening Tool) ..................... 2-14

Table 2-4: Average Temperature Range in the Rainy Season ............................................................. 2-15

Table 2-5: Number of Structures by Category and Basin Structures in .2% Annual Chance Exceedance (500-yr) Floodplain. ............................................................................................................ 2-17

Table 2-6: Total Value of Damageable Property, October 2014 Price Level ....................................... 2-18

Table 2-7: Annual Chance Exceedance (ACE) Event Damages by Index Point, October 2014 Price Level (in $1,000s) ......................................................................................................................... 2-18

Table 2-8: Without-Project Expected Annual Damages by Index Point, October 2014 Price Level ( in $1,000s) .............................................................................................................................. 2-19

Table 2-9: Expected Annual Damages and Benefits – West Sacramento Clean-Up and Temporary Evacuation, Relocation, and Housing Assistance (TERHA) Costs ........................................... 2-20

Table 2-10: Critical Infrastructure at Risk in w\West Sacramento ........................................................ 2-21

West Sacramento Project vii December 2015

Table 3.1 Comparison of Costs for Transitory Storage on the Sacramento River and Levee Raising ($ millions) ................................................................................................................................ 3-3

Table 3-2: Non-Structural Measures ................................................................................................... 3-12

Table 3-1: Measures and Objectives ................................................................................................... 3-13

Table 3-4: Measures Screening Criteria and Metrics........................................................................... 3-15

Table 3-5: Summary of Management Measures Retained or Dropped .............................................. 3-15

Table 3-6: Preliminary Alternative 0.5A – North Basin Protection Plan - Proposed Improvement Measures by Reach ............................................................................................................. 3-21

Table 3-7: Preliminary Alternative 0.5B – South Basin Protection Plan - Proposed Improvement Measures by Reach ............................................................................................................. 3-22

Table 3-8: Preliminary Alternative 0.5C – Mid-Cross Levee Alternative - Proposed Improvement Measures by Reach ............................................................................................................. 3-23

Table 3-9: Preliminary Alternative 0.5D – West Sacramento Basin Alternative - Proposed Improvement Measures by Reach ............................................................................................................. 3-24

Table 3-10: Preliminary Alternative 1 – Improve Levees - Proposed Measures by Reach .................... 3-25

Table 3-11: Preliminary Alternative 2 – Improve Levees and Widen the Sacramento Weir and Bypass - Proposed Improvement Measures by Reach ..................................................................... 3-26

Table 3-12: Preliminary Alternative 3 – Improve Levees and Deep Water Ship Channel (DWSC) Closure Structure – Proposed Measures by Waterway ................................................................... 3-27

Table 3-13: Preliminary Alternative 4 – Improve Levees, DWSC Closure Structure, and Widen Sacramento Weir and Bypass - Proposed Measures by Reach .......................................... 3-28

Table 3-14: Preliminary Alternative 5 – Improve Levees and Southport Setback Levee – Proposed Measures by Reach ............................................................................................................. 3-29

Table 3-15: Preliminary Alternative 6 - I Street Diversion Structure - Proposed Improvement Measures by Reach .............................................................................................................................. 3-30

Table 3-16: Preliminary Alternative 7 – Upstream Storage on the American River - Proposed Improvement Measures by Reach ...................................................................................... 3-33

Table 3-17: Preliminary Alternative 8 - Maximum Plan - Proposed Improvement Measures by Reach .............................................................................................................................. 3-34

West Sacramento Project viii December 2015

Table 3-18: Evaluation Metric Criteria and Study Objectives ................................................................ 3-36

Table 3-19: Comparison of Preliminary Array of Alternatives to the Final Objectives .......................... 3-36

Table 3-20: Evaluation of Costs and Benefits of the Preliminary Array of Alternatives ........................ 3-38

Table 3-21: Screening of the Preliminary Array of Alternatives ............................................................ 3-39

Table 3-22: Final Alternative 1 – Costs .................................................................................................. 3-48

Table 3-23: Final Alternative 3 – Costs .................................................................................................. 3-53

Table 3-24: Final Alternative 5 – Costs .................................................................................................. 3-57

Table 3-25: Evaluation Metrics Criteria and Study Objective ................................................................ 3-58

Table 3-26: Comparison of the Final Array of Alternatives to the Study Objectives ............................. 3-58

Table 3-27: Final Alternative 1 - Improve Levees – Proposed Levee Improvement Measures by

Reach .................................................................................................................................. 3-59

Table 3-28: Final Alternative 3 – Improve Levees and DWSC Closure Structure- Proposed Levee Improvement Measures by Reach ...................................................................................... 3-60

Table 3-29: Final Alternative 5 – Improve Levees and include Southport Setback Levee- Proposed Levee Improvement Measures by Reach ...................................................................................... 3-61

Table 3-30: Average Annual Benefits for Final Alternatives 1, 2, and 3 ................................................ 3-61

Table 3-31: Estimated Costs for Alternatives 1, 2 and 3 ........................................................................ 3-62

Table 3-32: Comparison of Total Annual Benefits and Costs ($1000’s) for Final Alternatives 1, 3, and 5 ....................................................................................................... 3-63

Table 3-33: Summary System of Accounts Comparison of Final Array of Alternative Plans ................. 3-66

Table 3-34: Assurance by Annual Exceedance Event - ......................................................................... 3-69

Table 4-1: Recommended Plan Proposed Improvement Measures by Reach ...................................... 4-2

Table 4-2: Alternative 5 – Construction Sequence and Duration ........................................................ 4-11

Table 4-3: Redundancy, Robustness, and Resiliency ........................................................................... 4-12

Table 4-4: Environmental Impacts of and Proposed Mitigation/Compensation for the TSP .............. 4-13

Table 4-5: Real Estate Costs for the TSP .............................................................................................. 4-14

Table 4-6: Emergency Activation Triggers ........................................................................................... 4-23

West Sacramento Project ix December 2015

Table 4-7: Summary of Environmental Effects and Mitigation Measures ........................................... 4-27

Table 4-8: Refined Cost Estimate for the Recommended Plan ........................................................... 4-38

Table 4-9: Final Net Benefits and Benefits to Cost Ratio – Recommended Plan ................................. 4-39

Table 4-10: Estimated Costs of the Recommended Plan....................................................................... 4-40

Table 4-11: Summary of Cost Sharing Responsibilities for the Recommended Plan1 (working level estimates based on MCACES) ............................................................................................. 4-41

Table 5-1: Authorized and Constructed Project Feature ....................................................................... 5-1

Table 5-2: Economic Analysis of the Selected Plan ($1,000) ................................................................. 5-3

Table 5-3: Cost Apportionment of Authorized Plan ($1,000) ................................................................ 5-4

Table 5-4: Cost Apportionment of Authorized Plan and TSP ($1,000) .................................................. 5-4

Table 5-5: Constructed and Unconstructed Parts of Recommended Plan ($1,000) ............................. 5-6

Table 5-6. Implementation Schedule..................................................................................................... 5-7

LIST OF FIGURES

Figure 1: Study Area ...................................................................................................................... PAC-3

Figure 1-1: West Sacramento Study Area. ............................................................................................ 1-5

Figure 1-2: Location of the Study Area within the Sacramento River Watershed ................................ 1-7

Figure 1-3: Features of the Sacramento River Flood Control Project ................................................ 1-12

Figure 1-4: Authorized West Sacramento Projects ............................................................................. 1-14

Figure 1-5: Studies and Projects within the Sacramento River Watershed ........................................ 1-17

Figure 1-6: West Sacramento Early Implementation Projects ............................................................ 1-18

Figure 2-1: West Sacramento Area 2-year to 500-year Flood Plains: ................................................... 2-5

Figure 2-2: Locations of Needed Levee Improvements ........................................................................ 2-9

Figure 2-3: Locations of Index Points .................................................................................................. 2-13

Figure 2-4: The Sacramento River Facing Downstream Toward the I Street Bridge ........................... 2-17

Figure 3.1 Transitory Storage Areas ..................................................................................................... 3-4

Figure 3-2: Implementation of Flood Risk Management Solutions .................................................... 3-11

West Sacramento Project x December 2015

Figure 3-3: Final Alternative 1 ............................................................................................................. 3-47

Figure 3-4: Final Alternative 3 ............................................................................................................. 3-52

Figure 3-5: Final Alternative 5 ............................................................................................................. 3-56

Figure 4-1: Extents of Vegetation Removal and Variance on the Sacramento River with the TSP ....... 4-4

Figure 4-2: TSP Recommended Features .............................................................................................. 4-7

Figure 4-3: Inundation times, flood depths, and evacuation routes for the South Basin ................... 4-24

Figure 4-4: Inundation times, flood depths, and evacuation routes for the North Basin ................... 4-25

LIST OF ACRONYMS

ASA(CW) ............................................................................... Assistant Secretary of the Army for Civil Works

CDFG............................................................................................... California Department of Fish and Game

CEQA .................................................................................................... California Environmental Quality Act

CERCLA ..................................... Comprehensive Environmental Response, Compensation, and Liability Act

CFR ..................................................................................................................... Code of Federal Regulations cfs ................................................................................................................................ Cubic Feet per Second

CVFPP .................................................................................................... Central Valley Flood Protection Plan

CVIFMS ......................................................................... Central Valley Integrated Flood Management Study

DPR ............................................................................................................................ Detailed Project Report

DWR ........................................................................................... California Department of Water Resources

DWSC ..................................................................................................................... Deep Water Ship Channel

EIR ................................................................................................................... Environmental Impact Report

EIS .............................................................................................................. Environmental Impact Statement

EO .......................................................................................................................................... Executive Order

West Sacramento Project xi December 2015

ER ............................................................................................................................... Engineering Regulation

ERR ................................................................................................................ Economic Reevaluation Report

ESA ............................................................................................................................Endangered Species Act

ETL ..................................................................................................................... Engineering Technical Letter

FAA ............................................................................................................... Federal Aviation Administration

FEIS .................................................................................................... Final Environmental Impact Statement

FEMA ............................................................................................. Federal Emergency Management Agency

Framework ............................................................... Central Valley Flood System Improvement Framework

FRM .......................................................................................................................... Flood Risk Management

GAO ....................................................................................................................... General Accounting Office

GRR ................................................................................................................... General Reevaluation Report

IDC ..................................................................................................................... Interest during Construction

JFP ............................................................................................................. Folsom Dam Joint Federal Project

LCM ........................................................................................................................... Life Cycle Management

MOA ................................................................................................................. Memorandum of Agreement

MSL......................................................................................................................................... Mean Sea Level

NED ............................................................................................................ National Economic Development

NEPA ......................................................................................................... National Environmental Policy Act

NGVD29 ........................................................................................National Geodetic Vertical Datum of 1929

NMFS ......................................................................................................... National Marine Fisheries Service

NOI ......................................................................................................................................... Notice of Intent

NRHP ....................................................................................................... National Register of Historic Places

OMRR&R ......................................... Operation and Maintenance, Repair, Replacement and Rehabilitation

PAC ........................................................................................................... Post-Authorization Change Report

PED ..................................................................................................Preconstruction Engineering and Design

West Sacramento Project xii December 2015

PL .................................................................................................................................................... Public Law

RD ................................................................................................................................... Reclamation District

RM ................................................................................................................................................... River Mile

ROD ................................................................................................................................... Record of Decision

Sac Bank ...................................................................................... Sacramento River Bank Protection Project

Sac Urban ............................................................................ Sacramento Urban Levee Improvement Project

SAFCA ............................................................................................... Sacramento Area Flood Control Agency

SCB .............................................................................................................................. Soil Cement Bentonite

SPF .............................................................................................................................. Standard Project Flood

SR ................................................................................................................................................. State Route

SRA ........................................................................................................................... Shaded Riverine Aquatic

SRFCP .............................................................................................. Sacramento River Flood Control Project

USBR .................................................................................................... United States Bureau of Reclamation

USFWS ............................................................................................................... U.S. Fish and Wildlife Service

VELB ......................................................................................................... Valley Elderberry Longhorn Beetle

WRDA ......................................................................................................Water Resources Development Act

WSAFCA ................................................................................. West Sacramento Area Flood Control Agency

Post Authorization Change Report PAC

West Sacramento Project 1 December 2015

WEST SACRAMENTO PROJECT,

POST AUTHORIZATION CHANGE REPORT

1. INTRODUCTION

This post authorization change report is being prepared to document a general reevaluation study of the West Sacramento project. The purpose of the West Sacramento Project is to reduce the flood risk for the City of West Sacramento. The general reevaluation report (GRR) has evaluated system improvements and additional levee improvements and other measures necessary to provide flood risk management for the City of West Sacramento.

2. DESCRIPTION OF AUTHORIZED PROJECT

2.1 Study Location

The study area is located in eastern Yolo County in the north central region of California’s Central Valley.

The study area approximately corresponds with the city limit for the City of West Sacramento comprising 13,000 acres of mixed-use land and an estimated population of 48,000 residents. The City of West Sacramento is located directly across the Sacramento River from the City of Sacramento, the State’s Capitol.

The project area is almost completely bound by floodways and levees [Figure 1]. The study area is bound by the Yolo Bypass to the west, the Sacramento Bypass to the north, and the Sacramento River to the east. Further, the City is bifurcated by the Sacramento River Deep Water Ship Channel (DWSC) and Barge Canal. The associated levee system currently protecting the study area includes nearly 50 miles of levees in Reclamation District (RD) 900, RD 537, Maintenance Area 4, and along the DWSC and Barge Canal. A description of these sub-basins and the levee reaches that comprise each includes the following:

Northern Sub-basin – The northern sub-basin, representing approximately 6,100 acres, is bounded by the Port North area and the DWSC to the south, the Sacramento River North Levee to the north and east, the Sacramento Bypass Levee to the north, and the Yolo Bypass Levee to the west. The right bank of the Sacramento River extends for approximately 5.5 miles of the northern and eastern sides of the basin.

Southern Sub-Basin – The Southern Sub-Basin encompasses approximately 6,900 acres and varies from El. 18.0 feet to El. 8.0 feet. The area is bounded by the Port South Levee and the DWSC to the north, the Sacramento River South Levee to the east, the South Cross Levee to the south, and the DWSC East Levee to the west. The right bank of the Sacramento River extends for approximately 6.2 miles on the east side of the basin.

A majority of the levees within the study area are part of the Sacramento River Flood Control Project.

The few exceptions are the Port North area and Port South levees, the DWSC West levee and the South Cross levee. The Port South and DWSC West levees were constructed as part of the Port of Sacramento.

West Sacramento Project 2 December 2015

The Port North area includes high ground along the northern portion of the Port of West Sacramento.

The South Cross levee is a private levee. Although the DWSC West levee was constructed as part of the navigation project supporting the Port of West Sacramento, this levee provides significant flood benefits to portions of both the northern and southern sub-basins. The Corps currently maintains this navigation levee.

The study area lies within the jurisdiction of the following Congressional Districts:

6th District (Doris Matsui)

Additional Congressional Districts that are not located within the study area but near its borders are:

3rd District (John Garamendi) 4th District (Tom McClintock 7th District (Ami Bera)

West Sacramento Project 3 December 2015

Figure PAC-1: Map of the Project Area.

West Sacramento Project 4 December 2015

2.2 Project Sponsors

The non-Federal sponsors for the GRR are the State of California Central Valley Flood Protection Board (CVFPB) and the West Sacramento Area Flood Control Agency (WSAFCA).

2.3 Authorized Project Features

The authorized West Sacramento project is a single purpose flood risk management project with an authorized total cost of $53,040,000 (2010). The project includes the following features:

• Raising and installing a slurry wall along 4.7 miles of the east bank of the Yolo Bypass levee from the Sacramento Bypass south to the Deep Water Ship Channel West Levee.

• Reconstructing and raising the levee along one mile of the south bank of the Sacramento

Bypass, including backfill of a drainage ditch and placing riprap along the levee.

2.4 Authorized Local Cooperation Requirements

Authorized Local Cooperation includes requirements to:

• Provide lands, easements, and rights-of-way.

• Modify or relocate utilities, roads, bridges (except railroad bridges), and other facilities, where necessary for the construction of the project.

• Bear all costs of operation, maintenance, repair, rehabilitation, and replacement of flood control facilities.

3. AUTHORIZATION

The West Sacramento project was authorized in Section 101(4) of the Water Resource Development Act (WRDA) of 1992, Pub. L. No. 102-580, § 101(4), 106 Stat. 4797, 4801-4802 (1992) (hereinafter WRDA 1992), and revised and supplemented through the Energy and Water Development and Appropriations Act (EWDAA) of 1999, Pub. L. No. 105-245, 112 Stat. 1838, 1840-1841 (1999) (hereinafter EWDAA 1999), and through Section 118 the EWDAA of 2010. EWDAA 2010, Pub. L. No. 111-85, § 118, 123 Stat. 2845, 2852 (2009).

New authority will be required for the changes to the project as a result of the reevaluations contained in this report. Engineering Regulation (ER) 1105-2-100, Planning Guidance Notebook, states that “an increase in total project cost, exclusive of price level changes, of more than twenty percent of the total project cost stated in the authorizing legislation” requires authorization by Congress. Project costs are expected to increase by more than 20%.

4. FUNDING SINCE AUTHORIZATION

Since the project’s authorization as part of WRDA 1992 portions of the project have been implemented by the Corps of Engineers under a Project Cooperation Agreement (PCA) executed with the California Reclamation Board (now the Central Valley Flood Protection Board) in May 1996. Table PAC.1 lists the West Sacramento work sites and their status.

West Sacramento Project 5 December 2015

Table PAC. 1: West Sacramento Project Work Sites and Status.

Item Feature Authorization, Overview, and Status

Raising and installing a slurry wall along 4.7 miles of the east bank of the Yolo Bypass levee from the Sacramento Bypass south to the Navigation Levee.

Authorization: WRDA 1992. Overview: general seepage remediation and raising levee height on the Yolo Bypass levee. Status: Improvements completed in 2001.

Reconstructing and raising the levee along one mile of the south bank of the Sacramento Bypass, including backfill of a drainage ditch and placing riprap along the levee.

Authorization: WRDA 1992. Overview: general seepage, stability, and height remediation on the Sacramento Bypass levee. Status: Improvements completed in 2001.

A funding history, by fiscal year, is shown in Table PAC-2, History of Federal Funding, indicating the category in which funds have been appropriated and the items of work (listed in Table 1) for which the funds have been utilized.

Table PAC. 2: History of Federal Funding.

Fiscal Year

Federal General

Investigations

Federal Construction

General 1996 $999,000

1997 $209,000

1998 $6,944,000

1999 $618,000

2000 $3,093,000

2001 $3,898,000

2002 $399,000

2003 $2,837,700

2004 $1,410,000

2005 $1,800,000

2006 $0

West Sacramento Project 6 December 2015

Fiscal Year

Federal General

Investigations

Federal Construction

General 2007 $0

2008 $4,373,000

2009 $3,000,000

2010 $448,000 $0

2011 $5,000,000

2012 $0

2013 $0

2014 $0

2015 $0

5. CHANGES IN SCOPE OF AUTHORIZED PROJECT

The scope of the authorized project is not adequate to address the residual flood risk for the West Sacramento area, and construction of the features authorized thus far has caused the project to reach its authorized cost limit. Therefore, the scope of the authorized project will increase. Potential types of scope expansion are measures to address seepage, stability, erosion, and levee height concerns throughout the system of levees that surround West Sacramento. Table PAC-3 shows the constructed features of the authorized project. The additional changes recommended as part of this GRR are presented below.

Table PAC-3: Constructed Features in West Sacramento.

Sacramento Urban Area Levee Reconstruction Project

Construction of berms to improve stability and manage seepage at two relatively small sites along the right bank of the Sacramento River near the Lighthouse Marina and approximately six miles of levee along the right bank of the Sacramento River extending from near the Barge Canal entrance downstream to near the South Cross levee. Construction began in November 1990 and was completed in 1992.

Sacramento Metropolitan Area, 1992 and 1999 Authorization (West Sacramento Project)

Raising and installing a slurry wall along 4.7 miles of the east bank of the Yolo Bypass levee from the Sacramento Bypass south to the Navigation Levee. Reconstructing and raising the levee along one mile of the south bank of the Sacramento Bypass, including backfill of a drainage ditch and placing riprap along the levee. Construction was completed in 2002.

In addition to the features included in the 1999 authorization, the recommended plan includes the additional features to improve the plan for flood risk management to the entire West Sacramento project area. The principal features of this plan are:

West Sacramento Project 7 December 2015

• 18,500 feet of cutoff walls to address seepage remediation and stability problems and 15,000 feet of rock bank protection to address erosion problems along the Sacramento River North levee.

• 8,400 feet of cutoff walls and slope flattening to address seepage and stability concerns on the Yolo Bypass levee.

• 3,000 feet of bank protection to address erosion concerns on the Sacramento Bypass training levee.

• Construct 550 feet of sheet pile wall with embankment fill to plug gap in the Sacramento River levee east of Stone Lock.

• Construct 30,000 feet of setback levee with slurry cutoff walls and/or seepage berms to address seepage remediation, and rock bank protection to address erosion problems along the Sacramento River South levee.

• Construct relief wells and 1,100 feet of stability berm to address seepage remediation and stability problems along the South Cross levee.

• 14,600 feet of cutoff walls to address seepage remediation along the Deep Water Ship Channel East levee.

• 1,000 feet of cutoff walls to address seepage remediation along the Port South levee.

• 25,000 feet of cutoff walls to address seepage remediation and 100,000 feet of rock bank protection to address erosion problems along the Deep Water Ship Channel West levee.

6. CHANGES IN PROJECT PURPOSE

There are no changes in the project purpose. Flood risk management is the single project purpose for both the authorized project and the project recommended in the general reevaluation study.

7. CHANGES IN LOCAL COOPERATION REQUIREMENTS

As indicated above, the non-Federal sponsor for the project are the CVFBP and WSAFCA.

The original project was authorized with cost sharing of 75% Federal and 25%. Cost sharing for flood risk management projects under the requirements of WRDA 1986, as amended, is 65% Federal and 35% Local. Any new project components recommended in this report would be cost-shared at 65% Federal and 35% Local.

The State of California and WSAFCA have expressed their support of the recommended project set forth general reevaluation report. The non-Federal sponsors have certified that they are financially capable of participating in the selected plan.

8. CHANGE IN LOCATION OF PROJECT

There is no change in the project location.

9. DESIGN CHANGES

The final report describes the recommended design changes. It is anticipated that these design changes will include construction of cutoff walls that are significantly deeper than originally constructed for the West Sacramento Project

West Sacramento Project 8 December 2015

10. CHANGES IN TOTAL PROJECT FIRST COSTS

Table PAC-4, Project First Cost, is a four-column comparison of the estimated cost for the project being recommended, the project as authorized by Congress, the authorized project updated to current price levels, and the current project cost estimate.

Table PAC- 4: Project First Cost ($000).

Construction Item

GRR

Recommended Plan

Project as Authorized1

Project as Last

Presented to Congress2

Current Project Cost

Estimate3

Lands and Damages 148,777 1,880 2,388 2,387 Relocations 81,946 15 128 128 Fish & Wildlife Facilities 46,188 2,400 3,201 3,044 Levees & Floodwalls 529,162 10,200 35,370 28,394 Bank Stabilization 166,011 0 0 0 Cultural Resources Preservation 7,639 131 0 0 Subtotal 979,723 14,626 41,087 33,913 Planning Engineering & Design (PED) 136,709 1,665 9,526 10,690 Construction Management 74,097 1,132 2,007 2,034 Total First Cost 1,190,528 17,423 52,620 46,677 Associated Costs 0 0 0 Total Costs 1,190,528 17,423 52,060 46,677

1 Project Cost from Sacramento Metropolitan Area, California Feasibility Report, February 1992

2 Project Cost based on Project Cost Estimate from June 2009.

3 Project Cost based on Project Cost Estimate from June 2011

11. CHANGES IN PROJECT BENEFITS

Table PAC-5, Economic Summary, shows a comparison of the benefits given in the project document, the benefits last reported to Congress, and the benefits based on reevaluations that have been done to support the recommended changes to the project. The evaluation of benefits has been limited to those that would accrue to structures and contents and do not include other benefit categories at this time, such as savings in emergency costs. Table 5 shows a breakdown of first and annual costs and benefits of the recommended plan, along with net economic benefits and benefit-to-cost ratio.

West Sacramento Project 9 December 2015

Table PAC-5: Economic Summary ($000).

Item

GRR

Recommended Plan

Authorized Project Authorized

Cost/Benefits1 Project as Last

Presented to Congress2 Current Estimate3

First Cost 1,182,8894 17,400 52,060 46,677 Interest During

Construction

(IDC)

442,752 1,600 4,7875 4,1955

Total 1,625,641 19,000 56,847 50,872 Annual Costs

Interest and Amortization 64,689 1,680 2,955 2,419

OMRR&R 106 20 206 206

Subtotal 64,795 1,700 2,975 2,439

Monetary Benefits

(FRM) 210,570 9,800 9,8007 9,8007

Net Annual FRM Benefits 145,775 8,100 6,825 7,361 FRM Benefit-Cost Ratio 3.2 5.8 3.3 4.0

1.Authorized Cost from 1992 Sacramento Metropolitan Area Feasibility Report 2 Project Cost based on Project Cost Estimate from June 2009

3. Project Cost Estimate from SPK, June 2011

4. Excludes cultural resource preservation costs

5. IDC was calculated based on a ratio of IDC to first costs from 1992 feasibility study

6. OMRR&R costs taken from 1992 feasibility study

7. Benefits have not been recalculated, benefits from 1992 feasibility study carried forward

12. BENEFIT-COST RATIO

Estimated total annual costs and annual benefits are calculated at an interest rate of 3.125 percent, over a 50-year period of economic evaluation. Table PAC.4 above shows the benefit-to-cost ratio.