Investing in Comprehensive Approaches to Flood Management: 2014 Flood Management Report

Wilbur Huang, P.E., CFMJason Brabec, P.E., CFM

Flood Projects OfficeDivision of Flood ManagementCalifornia Department of Water Resources

September 8, 2016

Collaborative Flood Risk Reduction Projects in the Greater Sacramento Region

Earlier Historic Floods2

Birds-eye view of Sacramento 1857; Historic floods of 1861-62 (USGS)

Birds-eye view of Sacramento 1857; the historic floods of 1861-62 (USGS)2

Flood of 19863

Flood of 1997

More Recent Historic FloodsBroken Gate on Folsom Dam (1995)

In February 1986, a series of storms led to severe flooding in central and northern California. In many areas, precipitation from this 10-day storm delivered more than half of the normal annual precipitation for the area. The Sacramento River flood control system was overloaded and one reservoir in the system (Folsom Dam) was filled beyond its design capacity. In mid- to late-December 1996, heavy snow fell in the Sierra Nevada Mountains. This was followed by heavy precipitation on the western slope of the mountains. The rain began to fall on December 26, and from December 31 to January 3, an atmospheric river (locally known as a Pineapple Express) brought approximately 30 inches of rain on the western slopes of the Sierra Nevada, in the process dumping more than half a years worth of rain on Northern California in 10 days. 3

4 Sacramento Floods: 1850, 1852, 1862 Sacramento raised almost 15 ft after 1862 flood 1880 First Comprehensive Flood Control Plan developed by William Hammond Hall More floods 1902-1909 1917 Plan from 1880 finally accepted Sacramento Flood Control System authorized by Congress 1944 Folsom Dam authorized Designed to provide 500-year level of flood protection 1951 Record Flood 1956 Record Flood 1964 Record Flood Folsom Dam flood protection downgraded to 120-year storm 1986 Record Flood Folsom Dam flood protection downgraded to 60-year storm! 1997 Record Flood Definitely a theme

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SPONSORS OF FLOOD RISK REDUCTION PROJECTS9/2/20166Federal Sponsor:United States Army Corps of Engineers (USACE)Project Management by Sacramento District (USACE-SPK)Non-Federal Sponsors:Central Valley Flood Protection Board (Board)Project Management by Department of Water Resources (DWR) Flood Projects Office and Board Staff CoordinationSacramento Area Flood Control Agency (SAFCA)

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Folsom Dam Modifications, JFP

ARCF, WRDA 96/99 Sites

ARCF, GRR ProjectSac Weir

South Sacramento County Streams ProjectARCF, GRR ProjectNorth Area StreamsARCF, GRR ProjectPocket LeveesARCF, Natomas Basin

American River Common Features, WRDA 96/99 Sites9/2/20168

AMERICAN RIVER WRDA 1996 AND 1999 COMMON FEATURES REMAINING SITES

Existing Cut-Off Wall

Rivers

Project Levees

Incomplete

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ARCF Project Background Project Cooperation Agreement (PCA) and Local Project Cooperation Agreement (LPCA) signed in July 1998.Under WRDA 96 authorization: 22 miles of cutoff wall was installed along American River, leaving about 32 gaps due to the needs of complex design and construction.Gaps include Bridge crossings, Railway line crossings, Pipe crossings, Overhead utility lines, etc.

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ARCF Project Finance (Estimate)9/2/201610Total Project Cost-$ 326 millionFederal Share-$ 243 millionNon-Federal Share -$ 81 millionState Cost Share -$ 56 mSAFCA Cost Share -$ 25 m

ARCF Construction Photos9/2/201611Work at Howe Ave BridgeHowe Ave Bridge cutoff wallJet Grouting at Watt Ave BridgePipe Crossings at L5A

Under WRDA 99 authorization design was completed to close all the gaps

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ARCF Project Accomplishments25 miles of continuous seepage cutoff wall 200-year Level of Flood Protection for more than 500,000 people and several billion dollar worth assetsSafely passage the 160k cfs release from the Folsom Dam during high water eventsTwo ASCE awards (2012 and 2014) for best construction practiceApril 2016 Project Completion

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South Sacramento County Streams Project

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2016 Work

Completed WorkI-5SR 99Beach-Stone Lake BasinMorrison CreekFlorin CreekElder CreekUnionhouse CreekUPRR

Morrison Creek Stream Group Basin

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SSS Project BackgroundFinal Feasibility report and EIS/EIR completed in March 1998Authorized in WRDA of 1999Limited Reevaluation Report (LRR), included revised hydrology, and Environmental Assessment completed December 2004Project Cooperation Agreement (PCA) and Local Project Cooperation Agreement (LPCA) signed in May 2005

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Divided into Phases 1A, 1B1, 1B2, 2A, 2D1

SSS DESIGN & CONSTRUCTION STATUS15Approx. 7 miles of Flood WallApprox. 9 miles of levee improvementApprox. 1.5 miles of new leveeApprox. 200 acre ecosystem restoration

COMPLETED WORK:

SRCSDPhase 1APhase 1B1Phase 1B2Phase 2APhase 2D1

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Florin Creek Construction (2D1)Started in Summer 2016; scheduled to be completed in late 2016Little over a mile of channel bottom widening and slope flatteningLow flow concrete invert channel liningApprox. 350 feet retaining wallApprox. 170 feet sheet pile wall

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SSS Construction Photos9/2/201617Completed section of channel bottom

Slope paving

Rebar installation for retaining wall

Sheet pile installation

SSS Project Finance(Estimate)9/2/201618Total Project Cost -$ 93 millionFederal Share -$ 60 millionNon-Federal Share -$ 33 millionState Cost Share -$ 23 mSAFCA Cost Share -$ 10 m

SSS Project AccomplishmentsLevel of flood protection will increase to 100-year for South Sacramento AreaAbout 30,000 parcels will be in reduced flood riskAbout 28,000 residential properties are or will be eligible for Preferred Risk Flood Policies (PRP)More than 200 acre ecosystem restorationEnhance the recreation and restore wildlife habitat

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JFP PROJECT9/2/201620

The Folsom Dam Modification Project is a cooperative effort to improve flood damage reduction features, dam safety, and security of the Folsom Dam and its associated facilities to a 200-year or better level of Protection.

JFP Project BackgroundIntent of Project was to attenuate peak storms with earlier releases to achieve a greater than 200-year level of flood protection, within rated flow capacity of downstream levees.Mass excavation for Phases I & II completed by United States Bureau of Reclamation in January 2011.Project was presented at the FMA Conference held in 2012. This presentation will focus on construction updates since that time.JFP Project continued in three primary phases:Phase III: Control StructurePhase IV: Step Chute, Stilling Basin, Upper Chute, and Approach ChannelPhase V: Site Restoration.

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JFP CONSTRUCTION PHASES9/2/201622

JFP Project Finance(Estimate)9/2/201623Total Project Cost $ 833 millionFederal Share -$ 541 millionNon-Federal Share -$ 292 millionState Cost Share -$ 204 mSAFCA Cost Share -$ 88 m

APRIL 20119/2/201624

OCTOBER 20139/2/201625

JANUARY 20159/2/201626

JANUARY 20169/2/201627 of 35

JULY 20169/2/201628

STEP CHUTE & STILLING BASIN2013 2016

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CONTROL STRUCTURE COMPLETE (AUG 2015)9/2/201630

BULK HEAD GATE SIZE9/2/201631

MARINE BLASTING OF THE APPROACH CHANNEL9/2/201632

Construction ProgressNovember 2012August 2016PhaseDesignConstructionDesignConstructionPhase III100%34%100%99%Phase IV100%0%100%94%Phase V0%0%100%14%Overall86%15%100%95%

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3.8 million cubic yards of rock and soil excavated300,000 cubic yards of concrete poured30 million pounds of steel reinforcing

Control Structure is as tall as the Statue of Liberty.3.8 million cubic yards of rock and soil excavated enough to cover San Francisco 1-inch deep300,000 cubic yards of concrete poured Fill a football field 170 feet deep30 million pounds of steel reinforcing Enough to build two and a half Eiffel Towers

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FUTURE JFP ACTIVITIESConstruction Approach Channel final excavationRestoration of SiteWater Control ManualCommissioningTurn-over9/2/201634

Construction Approach Channel final excavation: In-the-wet (marine) and dry work.Restoration of Site.- Work completed by December 31, 2016.Water Control Manual Flow Routings through the Folsom Dam and new JFP Structure to achieve greater than 200-year level of flood protection.Commissioning Activities of operating the gates and other appurtenances for commissioning activities. Turn-over Turning the JFP facility to USABR for operation and maintenance.

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SAFCA PROJECTS IN THE WORKSAmerican River Common Features General Re-Evaluation Report (GRR)Habitat Restoration and Ecosystem Improvements (Corridor Management Plan)Levee and Channel Maintenance9/2/201635

Construction Approach Channel final excavation: In-the-wet (marine) and dry work.Restoration of Site.- Work completed by December 31, 2016.Water Control Manual Flow Routings through the Folsom Dam and new JFP Structure to achieve greater than 200-year level of flood protection.Commissioning Activities of operating the gates and other appurtenances for commissioning activities. Turn-over Turning the JFP facility to USABR for operation and maintenance.

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ARCF, GRR ProjectSac WeirARCF, GRR ProjectNorth Area StreamsARCF, GRR ProjectPocket LeveesCOORIDOR MANAGEMENT PLANNEMDC/North Area Streams

THANKS!

Appreciate your AttentionQuestions?

-Wilbur Huang & Jason M. Brabec9/2/201637