Yolo Bypass Comprehensive Study

The Sacramento River Basin is California’s largest, key watershed that is integral to a water system that serves the most populous state in the Nation and the fifth-largest economy in the world. Within its footprint sits the state’s capital, Sacramento, a critical metropolitan area with one of the highest residual flood risks in the Nation.

Federal, state, and local governments and stakeholders have worked cease­lessly for more than a century to develop water resource management solutions, particularly with regard to flooding, to protect life and property in the region. These efforts have enabled residential, industrial, commercial, and agricultural communities and businesses to safely develop, grow, and thrive, but these posi­tive changes also call for action to further reduce flood and life safety risk, protect and restore the surrounding wildlife habitats and natural ecosys­tems, and improve water supply reliability.

With climate change and the need to incorporate resiliency, the complexities of the challenges facing the Sacramento River Basin are only increasing as the state experiences more dramatic swings between flooding and drought. Debates about comprehensive management solutions are also occurring within a context where escalating needs for the same land, water, and environmental re­sources are manifesting themselves within the same geographic region.

Federal, state, local governments, and interest­ed stakeholders now recognize that single-pur­pose systems first built 100 years ago within the Sacramento River Basin — of which Yolo Bypass System is part — must be reevaluated and updated to address multiple public benefits simultaneously.

The Yolo Bypass System plays a key role in man­aging flood risk in the Sacramento River Basin. A confluence of interested stakeholder in this system initiated a partnership to explore the potential for more comprehensive water resources manage­ment, collaboration, and problem-solving. It is a hope of the partnership that success in this region could serve as a model for intergovernmental collaboration for the rest of California and the nation facing similar pressures and challenges in key watersheds.

Subsequently, Congress authorized a comprehensive study in 2020 which will enable the partners to establish a vision of a future sys­tem and investigate multiple project purposes (flood risk management, ecosystem restoration, water supply, hydropower, and recreation) for comprehensive management of the Yolo Bypass System. The Comprehensive Study team will en­gage stakeholders on a broader array of project purposes and develop different products and recommendations over time to address a variety of water resource management challenges.

Three years after authorization, Congress ap­propriated $500,000 in FY2023 to begin work on the study. On September 25, 2023, USACE signed a Feasibility Cost Share Agreement with the two non-federal sponsors: State of California Central Valley Flood Protection Board (CVFPB), and Sacramento Area Flood Control Agency (SAFCA).


Prior to the federal investment in flood control, and before extensive settlement in the area (pre- 1849), the Yolo Basin was one of many naturally occurring flood basins in the Lower Sacramento River system. The Yolo Basin was primarily natural land, with limited development and high habitat value. It also has a deep history of cultural signif­icance to 13 Native American Tribes.

As part of the Sacramento River Flood Control Project, the Yolo Basin was reclaimed and de­veloped primarily as farmland. Over the last 100 years, it has functioned primarily as a sin­gle-purpose flood-control facility, with other uses largely restricted.

Yolo Bypass And Vicinity Study Area Map

Contact Information

For more information on the
Yolo Bypass Comprehensive Study,
please contact us at the following



Mailing Address:
U.S. Army Corps of Engineers
1325 J Street, Room 1640
Sacramento, CA 95814