1. Delta Risk Management Strategy
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Delta Risk Management Strategy
The Delta Risk Management Strategy is a combined effort among the Department of Water Resources, the U.S. Army Corps of Engineers, and the Department of Fish and Game in cooperation with the California Bay-Delta Authority Later on I will explain a State law that requires both DWR & DFG to submit a report on DRMS. The COE will use the DRMS work for their Feasibility Study of the Sacramento-San Joaquin Delta Levees – the DRMS work will be the “Without Project” portion of the FS.
SCWC/SCWD MEETING
JUNE 27, 2007
Delta-Suisun Marsh Branch
Department of Water Resources

2. Water Supply for 23 Million People
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DRMS also includes the Suisun Marsh area, which is defined as the area east of the Benicia-Martinez Bridge on I-680
S-SJ Delta legally defined in CWC Section 12220
400,000 People
47% of State Runoff
500 Species
Water Supply for 23 Million People
Agricultural Water Supply for 3 Million Acres

3. DRMS Development of DRMS
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DRMS
Development of DRMS
2000 CALFED ROD Called for Risk Assessment of Delta Levees
2005 – Levee Risk Analysis Team
Did Preliminary Work – Seismic only
Also Developed Project Scope for DRMS
2005 – AB 1200 Enacted
2006- Governor’s Executive Order- Delta Vision
2005 Seismic report resulted in “How a Delta Earthquake Could Devastate California’s Economy” given by Director Snow to Senate Subcommittee on Delta Resources & Senate T&H Committee, Nov 2005
EXECUTIVE ORDER S /28/2006

4. DRMS AB 1200 (CWC 139.2) Sets General Framework for DRSM
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DRMS
AB (CWC 139.2) Sets General Framework for DRSM
DWR Shall Evaluate Potential Impacts on 50, 100, 200-year projections on possible impacts to Delta from:
Subsidence
Earthquakes
Floods
Climate Change
& Combination of above

5. DRMS AB 1200 Continued (CWC 139.4)
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DRMS
AB 1200 Continued (CWC 139.4)
DWR/DFG to Determine Principal Options for Delta – DWR to comparatively rate for ability to:
Prevent Disruption of Water Supplies Derived from Delta
Improve the Quality of Water Supplies Derived from Delta
Reduce Salts, Maintain Water Quality
Preserve, Protect, Improve Delta Levees
Protect Water Rights/Environments of River Systems
Protect Infrastructure within Delta
DFG shall rate all options for its ability to restore salmon & other fisheries that use the Delta
Report Due – January 2008

6. DRMS Contract Information URS Corporation, Oakland, CA
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DRMS
Contract Information
URS Corporation, Oakland, CA
Over 20 subcontractors
Approved by DGS - March 6, 2006
3-year contract
Includes a new LiDAR aerial survey of Delta
Guidance to URS – No new studies, use best available info, however, some limited exclusions:
Subsidence; Seismic hazard
DRMS report has several new models of Delta operations (i.e., Risk, Hydrodynamics, ER&R, Water Analysis)

7. DRMS Technical Memoranda
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DRMS
DRMS Technical Memoranda
Risk Analysis
Seismology (PSHA)
Ecological Impacts (Ecosystem)
Subsidence
Levee Vulnerability
Flood Hazard
Wind Wave Analysis
Climate Change
Water Analysis Module (Hydrodynamics)
Geomorphology
Impact to Infrastructure
Economic Consequences
Emergency Response & Repair
The Phase 1 report will consist of the following documents:
- Executive Summary report (10-18 pages)
Summary Report (50 pages)
Risk Analysis report (400 + pages)
All TMs (2,000 + pages)

8. DRMS Phase 1 Based on Business-As-Usual Assumptions
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DRMS
Phase 1
Based on Business-As-Usual Assumptions
Development of a Risk Analysis to Evaluate the Impact to Delta Levees from:
Floods
Earthquakes
Subsidence
Normal Conditions
Climate Change
Determine Consequences to Economy & Eco-System based on Risks Found
Draft Risk Analysis Report submitted April 23 ’07
Public Draft July 2007
Independent Review by CALFED – July – August ‘07

9. Summary of Key Findings from Phase 1 (preliminary)
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Summary of Key Findings from Phase 1 (preliminary)
flood-related island failures expected in the next 100 years
12-15 simultaneous island failures in a major flood event
15- 30% chance of 30+ islands failing simultaneously in a major earthquake in the next 25 years

10. Summary of Key Findings (continued)
Probability of flood-related levee failure
increases by 10% in 2050
Increases by 20% in 2100
Probability of seismic-related levee failure
increases by 12% in 2050
increases by 27% in 2100
3 feet of sea level rise would push the salt line about 3 miles to the east

11. 1/3/2019
DRMS
Phase 2
Development of Risk Reduction/Risk Management Strategies for Long-Term Management of Delta
Draft Final Report Due August ’07
Public Review Draft – Oct ’07
Independent Review by CALFED – Oct – Nov ’07
DRMS Final Report – November 2007
Includes Recommendations for Future Work/Studies in the Delta
Will be provided to Delta Vision Blue Ribbon Task Force for Consideration in the “Vision for the Delta”
As part of the Phase 2 report will be a list of recommended actions that should be taken in the Delta to help improve our knowledge. Examples are having USGS and CGS investigate faults in the Delta more extensively than in the past. Need for better topographic survey information, more subsidence work,

12. Delta Risk Management Strategy
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Delta Risk Management Strategy
Phase 2: Development and Evaluation of Risk Reduction Strategies
Develop a menu of risk reduction measures that could reduce risk – “building blocks”
Package the measures into different combinations -> “trial scenarios”
Use Risk Model to evaluate potential risk reductions
Evaluate benefits and costs of risk reduction measures

13. Delta Risk Management Strategy
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Potential Risk Reduction Building Blocks:
Improved Levee Maintenance
Upgraded Delta & Urban Levees
Enhanced Emergency Preparedness/Response
Pre-Flooding of Selected Western Islands
Land Use Changes to Reduce Subsidence
Armored Through Delta “Pathway” Conveyance
Isolated Conveyance
Elevation of State Highways on Piers
Armored Infrastructure Corridor
San Joaquin By-Pass
Suisun Marsh Restoration
Cache Slough Restoration
Fish Screens
Reduced Water Exports

14. DRMS Phase 2 Trial Scenarios Being Proposed
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DRMS Phase 2 Trial Scenarios Being Proposed
Improved Levees
Armored Pathway
Isolated Conveyance
More information is available on the building blocks and scenarios at both the Delta Vision and DRMS web sites.

15. Thank You For more information on the DMRS work, please
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Thank You
For more information on the DMRS work, please
see the DRMS web site at: