The Resources Agency California Department of Water Resources DWR Program for the Repair of the Cali

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The Resources AgencyCalifornia Department of
Water ResourcesDWR Program for the Repair of
the California Levee System
March 7, 2007
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Presentation Outline

• Background
• Description of Projects
• Critical Erosion Repairs
• PL84-99
• Urban Levee Geotechnical Evaluation

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Central Valley Flood Control System Projects

2.5 million people

2 million acres of cultivated land

200,000 structures with an estimated value of 57
billion

Water supply to 2/3rds of the States population
and industry
The system is aging and under-funded
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• KEY CHALLENGES IN CENTRAL VALLEY
• 1600 miles of Federal Project Levees
• 700 miles of local Delta Levees
• 2300 miles of Levees
• Old levees, many originally built by farmers,
  most without adequate engineering

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Methods and materials used during early
construction are inappropriate by todays
standards.
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Some methods included manual labor only. Repair
was generally reactive (as a result of periodic
failures).
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CRITICAL LEVEE EROSION REPAIRS PROJECT

• Annual Survey Commissioned by U. S. Army Corps
  of Engineers
• 2005 Survey reported 174 Erosion Sites

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Levee and Bank Erosion
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Levee Erosion
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3 ft in 4-6 hours
7 ft in 12-20 hours
10 ft in 24-36 hours
17 ft in 6-8 days
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• State Emergency Declaration
• Governor declared State of Emergency for States
  levee system (February 24, 2006)
• Directed DWR to repair 24 Critical Erosion Sites
  before the next flood season
• Directed DWR to evaluate additional sites to
  determine if other levee reaches require urgent
  repairs
• Directed all state agencies to alleviate the
  emergency in accordance with the State Emergency
  Plan
• USACE Declaration of Emergency
• ( For 24 new levee erosion sites (November 7,
  2006)
• Enables construction concurrent with
  environmental assessments and mitigation plans

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• Requested Federal Emergency Declaration
• Requested federal
• emergency assistance
• Full state-federal cost share
• Cooperation and assistance
• from the Corps of Engineers
• Expedite process for federal
• permits, construction

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Project Description Emergency LeveeErosion
Repairs

• Repair 24 critical erosion sites before November
  1, 2006
• 20 conventional rock reinforcement
• 4 set-back levees
• Identify and evaluate other sites degraded during
  sustained high flows throughout the wet season.
• Evaluated 11 potential critical sites
  determined that an additional 5 sites had
  degraded to critical status
• - need to repair these 5 newly critical
  sites!
• Evaluated 19 additional erosion sites at the
  request of local officials for consideration for
  emergency repairs

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Critical Site Sites where further erosion may
result in a bank failure, which encroaches near
or into the levee crown and is recommended as the
highest priority for repair
24 Original Critical Sites 5 Additional Sites
Found to be Critical (previously
potentially critical sites that have
deteriorated over the last year) _________________
___________________________________ 29 Current
Critical Sites 10 Critical Sites to be
repaired by USACE 19 Critical Sites to be
repaired by DWR __________________________________
______________ 29 Current Critical Sites
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Task Activitiesfor Repair of the Critical
Erosion Sites

• Environment Permitting
• Right of way acquisition
• Surveying and site assessments
• Design and prepare construction contracts
• Construct erosion repairs
• Incorporation of self-mitigation features to
  reduce environmental impacts associated with the
  project repairs.

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Typical Rock Fill Repair Design

• Example of a Self-mitigating Repair

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Typical Rock Fill Repair Design(Continued)
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Project GoalLong-term Bank Erosion Control and
Levee Stabilization
Mitigation FeaturesGoal is Self-Mitigation
SAC 85.6R
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• Protection of Existing Trees
• Installation of willow fascine bundles to
  propagate shaded riverine aquatic (SRA) habitat
  near the waters edge
• Installation of willow pole cuttings

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• Riparian bench (planting to be completed next
  spring)
• In-stream woody material (IWM) at multiple levels
  to maximize fisheries benefits
• Revegetation of all soil slopes (including rill
  erosion control).

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Key Regulatory Hurdles

• Clean Water Act Section 404/ Rivers and Harbors
  Act Section 10 (Corps)
• Endangered Species Act (NOAA and USFWS)
• National Environmental Policy Act (Corps)
• California Environmental Quality Act (DWR)
• Other State Programs (401, 1602)

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Land Access Critical Erosion Site Levee Repair
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Water Access Critical Erosion Site Levee Repair
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2005 Critical Repairs Status

• TOTAL CONSTRUCTION
• 29 of 33 sites (levee repairs) are structurally
  complete, with remaining mitigation vegetation
  planting planned for Spring 2007.
• 4 of 33 sites (setback levees) are fully
  complete.
• Cumulative Length of Repairs 33,800 LF (6.4
  mi.)
• TOTAL COST for 33 Sites
• 189.5 million dollars (150.3M State / 39.1M
  Federal)
• (5,700 per LF of self-mitigating repair).

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Catching up with 2006

• Critical Repairs had focused on 2005-identified
  sites.
• Two major storm events (January and April 2006)
  caused significant, additional flood damage
  throughout the State
• The 2006 field reconnaissance by the USACE on the
  Sacramento River mainstem and delta identified 24
  newly designated critical sites (excludes
  tributaries and bypasses).

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INCIDENTS

• DWR responded to
• over 60 incidents
• Central Valley 29
• Delta 27
• Suisun Marsh 3
• Coastal 3
• Sierra 1

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• INCIDENTS
• DWR responded to
• over 45 incidents
• Central Valley 21
• Delta 3
• Sierra 2
• Advanced Measures 19

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2006 Emergency Repairs Program
Priority 1 40 Order 1 (Urban) PL84-99
Sites Priority 2 24 2006 Ayres/USACE Critical
Erosion Priority 3 7 Order 2 (Rural) PL84-99
Sites (High B/C Ratios) 71 Critical
Levee Sites DEFERRED 44 Order 2 (Rural)
PL84-99 Sites (Low B/C Ratios)
75 Ineligible PL84-99 Sites
222 Non-Critical Order 3, 4, and 5
PL84-99 sites 341 Deferred Sites
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Critical Repairs Schedule

• Phased Construction of 24 Critical Sites
  (construct through the winter to place launch
  rock and abate scour to levee bank)
• Final repairs to be constructed Summer / Fall
  2007
• Complete repairs of 47 Order 1 2 PL84-99 sites
  by Summer / Fall 2007
• USACE to Re-assess economic opportunities to
  repair DEFERRED sites (341)
• USACE DWR - Continue monitoring known sites and
  conduct annual field reconnaissance to identify
  and prioritize new critical levee erosion sites.

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Estimated Cost of 2006 Repairs

• 24 Critical Levee Erosion Repairs
• State 43.2 Million
• Federal 61.5 Million
• 104.7 Million
• PL84-99 Repairs (47 sites)
• State Federal 40.4 Million
• EST. 2006 PROGRAM TOTAL 145.1 Million
• Combined 2005/2006 Program 334.5 Million
• (Source of funding AB-142)
• Environmental mitigation costs account for
  between 25-50 of the
• total capital construction cost.

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Urban Levee Geotechnical Evaluation

• Purpose Identify hidden deficiencies in levees
  that protect urban areas State and Federal
  Urban Levees.
• Evaluate levees with respect to
• Seepage
• Static and seismic stability
• Settlement
• Erosion
• 200-year level of flood protection
• Meet USACE/FEMA criteria for certification
• Preliminary design alternatives for identified
  deficiencies

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Urbanized Regions
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Hidden defects
Sand layer found in existing levee during
repairs. Layer goes through to other side
This area sustained significant seepage during
the 1997 event
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Scope of Work

• Geotechnical Evaluation
• Exploration
• Testing
• Data Analysis and Characterization

• Certification
• Structural works a statement that the works are
  designed in accordance with sound engineering
  practice
• As-built conditions a statement that the
  structures have been constructed according to
  the design, are in place and are fully
  functioning

Levee Decertified
GER

• Structural Design
• Embankment Height
• Closures
• Embankment Protection
• Embankment and Foundation Stability
• Settlement
• Seepage

Review Levee Freeboard
Operation Maintenance Plan
Submit LOMR/PMR
FEMA Review
Interior Drainage Analysis
Levee Accredited
DFIRM Revised
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Management Process Approach
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Focused on3 Major Areas

• This 35 million, 3-Yr effort is geographically
  executed
• North Area (Yuba City and Marysville Region)
• Central Area (Sacramento Region)
• South Area (Stockton Region)

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Program Schedule
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Additional, Concurrent DWR Activities

• American River Common Area provides for the
  improvement of American River levees protecting
  Sacramento (2.1M from AB-142 w/ USACE, Rec Bd,
  SAFCA)
• Sutter Bypass Weir 2 Improvements provides
  analyses and design to improve facility to meet
  environmental compliance (2.5M)
• Willow Slough Weir Improvements provides
  analyses and design to improve facility to meet
  environmental compliance (2.5M)
• Pump Station Rehabilitation provides for the
  improvements to facilities near Yuba City (2.5M)
• Fremont Weir Maintenance provides for the
  removal of approx. 800,000 CY of sediments near
  this flood control facility (2.0M)

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For more informationvisit DWRs Levee Website
at

• www.levees.water.ca.gov
• For water conditions, go to
• www.water.ca.gov
• then select Water Conditions

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Thank you