Department of Water Resources Home

Yolo Bypass


sutter bypass

Environmental Services

Dean Messer, Chief

3500 Industrial Blvd.
West Sacramento, CA 95691
(916) 376-9699

Mailing Address:
P.O. Box 942836
Sacramento, CA 94236-0001



Yolo Bypass Links

Why are we restoring fish habitat in the Yolo Bypass?

photo of Bypass Photo Credit: Sheena Holley

In 2009, the National Marine Fisheries Service (NMFS) issued a Biological Opinion and Conference Opinion on the Long-term Operations of the Central Valley Project and the State Water Project (BO). The NMFS BO determined that continued State and federal water project operations were likely to jeopardize the existence of four federally-listed fish species: Sacramento River winter-run Chinook Salmon, Central Valley spring-run Chinook Salmon, California Central Valley Steelhead, and the Southern Distinct Population Segment of North American Green Sturgeon. The NMFS BO contains a Reasonable and Prudent Alternative (RPA) to avoid jeopardizing the listed fish species. The RPA includes multiple actions related to the Yolo Bypass.

NMFS BO RPA Actions in the Yolo Bypass

The following actions apply to the Yolo Bypass and are under the purview of the Yolo Bypass Habitat Restoration Program.

  • RPA Action I.6.1 - Restoration of Floodplain Rearing Habitat

    Provide significantly increased seasonal floodplain rearing habitat availability with biologically appropriate durations and magnitude, from December through April, in the lower Sacramento River basin, on a return rate of approximately 1 to 3 years, depending on water year type. The initial habitat target, which may be modified, is 17,000-20,000 acres with appropriate frequency and duration of inundation.

  • RPA Action I.6.3 – Lower Putah Creek Enhancements

    Develop and implement lower Putah Creek enhancements, including stream realignment and floodplain restoration for fish passage improvements and multi-species habitat restoration on existing public lands. Ensure that this action will not result in migration barriers or stranding of juvenile salmon.

  • RPA Action I.6.4 – Improvements to Lisbon Weir

    Ensure that improvements to the Lisbon Weir are made that are likely to achieve fish and wildlife benefits and do not result in migration barriers to adult anadromous fish or stranding of juvenile salmon.

  • RPA Action I.7 – Reduce Migratory Delays and Loss of Salmon, Steelhead, and Sturgeon at Fremont Weir and Other Structures in the Yolo Bypass.

    Reduce migratory delays and losses of adult and juvenile Sacramento River winter-run Chinook salmon, Central Valley spring-run Chinook salmon, California Central Valley steelhead, and Southern DPS of green sturgeon at Fremont Weir and other structures in the Yolo Bypass.

Visit NMFS’s website on the Long-Term Operations of the Central Valley Project and State Water Project for more information and to view the entire Biological Opinion.