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

Yolo Bypass Salmonid Habitat Restoration and Fish Passage Project

photo of weir Fremont Weir. Photo Credit: Eva Olin


The Yolo Bypass Salmonid Habitat Restoration and Fish Passage Project will improve fish passage within and through the Yolo Bypass (providing the primary structure that will improve fish passage over a wide range of high flow conditions) and will enhance up to 17,000 acres of floodplain rearing habitat for juvenile salmonids (salmon and steelhead).

The project will consist of one or more gated or passive channels in the Fremont Weir, at the northern end of the Bypass. These changes will improve the connection between the Sacramento River and the floodplain from December through March 15, when the targeted juvenile fish are in the river. The increased flow will help young salmon by enhancing natural flooding, which now occurs in about 70% of years. An increased volume of water entering the Bypass will result in a greater floodplain area. Longer flooding will allow salmon to feed in a food-rich floodplain for a longer time where they can rapidly grow to a large size, thus improving their survival to the ocean. The increased flows will be managed to avoid or minimize effects on farmers’ spring planting time.

To improve fish passage, the project will also include modification to an agricultural road crossing in the Yolo Bypass, which consists of two 36" culverts with headgates. The road crossing is located near Fremont Weir.

DWR and Reclamation are working collaboratively with area landowners and governments to plan this project. Completion of this project will fulfill NMFS BO RPA Actions I.6.1 and I.7

Next Steps


Construction is anticipated to begin in or after 2020.

Planning and Design Status

The project is in the alternatives development phase, which includes conceptual engineering, impact analysis, and avoidance and minimization measures. A Final Environmental Impact Report/Environmental Impact Statement is expected in 2019.

DWR and Reclamation are holding a public workshop on June 29, 2017 at the Yolo Bypass Wildlife Area Headquarters in Davis to share information, answer questions, and get input from interested stakeholders on draft alternatives for the Yolo Bypass Salmonid Habitat Restoration and Fish Passage Project. See the Meeting Announcement for the agenda and details.