System Reoperation Study, Phase 3 Report: Assessment of Reoperation Strategies

The California Department of Water Resources (DWR) is conducting a System Reoperation Study (SRS) in cooperation with other State and federal agencies, local water districts, groundwater managers, and other stakeholders, to identify potential strategies for reoperation of the statewide flood protection and water supply systems. The opportunity to reoperate portions of California’s statewide water system to yield increased water resources-related benefits was recognized by the State Legislature in Senate Bill X2 1 (SB X2 1) (Perata 2008).

In support of the legislative objectives, DWR developed the SRS to identify viable reoperation strategies and understand how integrated management can:

• Improve the reliability of municipal and irrigation water supply.
• Reduce flood hazards.
• Restore and protect ecosystems.
• Buffer the hydrologic variations expected from climate change.
• Improve water quality.

California’s statewide water system is composed of a multitude of local, State, and federal projects. These projects include dams and reservoirs, hydropower plants, canals, and water diversion structures. Many of these facilities were developed in the early to mid-20th century, and were not designed, constructed, or operated as an integrated water supply and flood management system. Over time, operations of the two largest water supply projects, the State Water Project (SWP), operated by DWR, and the Central Valley Project (CVP), operated by the U.S. Department of the Interior’s Bureau of Reclamation (Reclamation), have been integrated to a certain degree.

California’s water supply and flood management infrastructure is physically interconnected to the extent that it is technically feasible to move water around the system, from Trinity County in the north to Imperial County in the south. However, the management of the water system is not as well integrated as it could be. The underlying logic of the SRS is that California can do much more with its existing water infrastructure by taking advantage of the physical interconnections (and enhancing them) while also operating the system in a coordinated manner to optimize the benefits.

The current focus of the SRS is the Central Valley, because this region has the highest integration of water supply and flood management facilities. Additionally, the greatest potential for ecosystem restoration through infrastructure reoperation is found in the Central Valley, because the existing infrastructure has had a profound effect on aquatic ecosystems. Figure ES-1 shows the location of the Central Valley and the study area for the SRS. Figure 1-1 also shows major features of the CVP and SWP.

RELATED DOCUMENTS:

System Reoperation Study, Phase 1: Plan of Study

System Reoperation Study, Phase 2: Strategy Formulation and Refinement

System Reoperation Study, Phase 2: Appendix A: Forecast?Based Operations Analysis

System Reoperation Study, Phase 2: Appendix B: Tradeoff Analysis

System Reoperation Study, Phase 3 Report: Assessment of Reoperation Strategies

System Reoperation, Phase 3: Appendix C: State Water Project and Central Valley Project Integrated Operations Analysis

System Reoperation, Phase 3 Appendix D: Ecosystem Evaluation