Levee evaluations for the SJRRP identify the need to remediate levees to convey Restoration Flows.
Priority 1 and Priority 2 Levee Geotechnical Evaluations: The San Joaquin Levee Evaluation Project is being implemented by DWR to conduct geotechnical evaluations of the flood control system integrity associated with levee seepage and stability on high-priority levees in the Restoration Area. To limit the risk of levee failure due to the release of Restoration Flows, channel capacities are limited to flow levels that would meet the U.S. Army Corps of Engineers (USACE) factors of safety for levee slope stability and underseepage. If data on the levees is not available to evaluate seepage and stability conditions, flows are limited to those that would remain “in-channel” until adequate data are available. From the initial geotechnical analysis findings, high flood hazards were identified for most San Joaquin River Restoration Program (SJRRP) levees. DWR has prioritized its geotechnical exploration based on current channel capacity limitations and anticipated Restoration Flow routing.
Priority 1 levee evaluations in Reach 2A, the lower portion of Reach 4A, and the middle Eastside Bypass are complete. The results showed that only one levee segment in these reaches — 2 miles of the right back of the Eastside Bypass below Sand Slough — cannot convey at least 2,500 cfs without exceeding USACE criteria. The 2-mile segment of levee was identified for improvements and DWR completed a Basis of Design report for this levee segment in 2017; 95% designs were completed in 2018. The levee improvement project is scheduled for construction in 2019.
Geotechnical evaluations also continued on the Priority 2 levees, which include the Mariposa Bypass and Reach 4B2. Data was collected on these levee segments in 2016. Geotechnical evaluations on the levees were completed in 2018 and a Geotechnical Conditions Report will be released in 2019. The report will include remediation alternatives and cost estimates that will help the SJRRP determine the costs of improving these levees under the Reach 4B, Eastside Bypass, and Mariposa Bypass Channel and Structural Improvements Project.
2025 Draft Channel Capacity Report
2025 Draft Channel Capacity Report
2024 Channel Capacity Report
2023 Channel Capacity Report
2022 Channel Capacity Report
- Appendix A – PEIS/R Text Related to Channel Capacity December 2012
- Appendix B – 2020 Levee Capacity Update in the Middle Eastside Bypass August 2021
- Appendix C – Bank Erosion Monitoring Report July 2021
2021 Channel Capacity Report
2020 Channel Capacity Report
- Appendix A – PEIS/R Text Related to Channel Capacity
- Appendix B – Evaluation of the Effects of Future Subsidence on Capacity by up to 2,500 cfs in Reach 4A and Middle Eastside Bypass
- Appendix C – Levee Capacity Evaluation of Mariposa Bypass and Reach 4B2 Study Area
- Appendix D – Response to Comments
2019 Channel Capacity Report
- Appendix A – PEIS/R Text Related to Channel Capacity
- Appendix B – Evaluation of the Effect of Subsidence on Flow Capacity in the Chowchilla and Eastside Bypasses, and Reach 4A of the San Joaquin River
- Appendix C – Evaluation of the Effects of Subsidence and Sediment Transport on Channel Capacity in the Eastside Bypass and Reach 4A of the San Joaquin River
2018 Channel Capacity Report
- Appendix A- PEIS/R Text Related to Channel Capacity
- Appendix B- Reach 2A and 2B Update San Joaquin River In-channel Capacity Analysis
- Appendix C- Reach 2A Update- Levee Capacity Evaluation of Geotechnical Gravelly Ford Study Area
2017 Channel Capacity Report
- Appendix A – PEIS/R Text Related to Channel Capacity
- Appendix B – Updated San Joaquin River In-channel Capacity Analysis
- Appendix C – Levee Capacity Evaluation of Geotechnical Gravelly Ford (Reach 2A) Study Area
- Appendix D – Levee Capacity Evaluation of Geotechnical Middle Eastside Bypass (Reach 4A, Sand Slough Connector Channel, Upper and Middle Eastside Bypass) Study Area
2016 Channel Capacity Report
- Appendix A – PEIS/R Text Related to Channel Capacity
- Appendix B – Updated San Joaquin River In-channel Capacity Analysis
- Appendix C – Levee Capacity Evaluation of Geotechnical Gravelly Ford (Reach 2A) Study Area
- Appendix D – Levee Capacity Evaluation of Geotechnical Middle Eastside Bypass (Reach 4A, Sand Slough Connector Channel, Upper and Middle Eastside Bypass) Study Area
- Appendix E – Response to Comments
2015 Channel Capacity Report
- Appendix A – PEIS/R Text Related to Channel Capacity
- Appendix B – Hydraulic and Sediment Transport Modeling Strategy
- Appendix C – San Joaquin River In-Channel Capacity Analysis
- Appendix D – Middle Eastside Bypass Geotechnical Assessment
- Appendix E – Technical Memorandum Subsidence Monitoring (2011-2013)
- Appendix F – Responses to Comments
2014 Channel Capacity Report
- Appendix A – PEIS/R Text Related to Channel Capacity
- Appendix B – San Joaquin River In-channel Capacity Analysis
- Appendix C – Middle Eastside Bypass Geotechnical Assessment
- Appendix D – Reach 2A Sedimentation Evaluation (2011)
- Appendix E – Draft Technical Memorandum Subsidence Monitoring (2011-2013)
- Appendix F Evaluation of the Effect of Subsidence on Flow Capacity in the Chowchilla and Eastside Bypasses
- Appendix G – Identification and Prioritization of Levee Segments for Geotechnical Exploration and Analyses
- Appendix H – Response to Comments