USACE announces high-flow release at Coyote Valley Dam

U.S. Army Corps of Engineers San Francisco District
Published Jan. 15, 2023
Updated: Jan. 15, 2023
The South Boat Ramp at Lake Mendocino on Jan. 13, 2023.

The South Boat Ramp at Lake Mendocino on Jan. 13, 2023.

SAN FRANCISCO – The U.S. Army Corps of Engineers San Francisco District (USACE) will begin a series of high-flow releases from Coyote Valley Dam at Lake Mendocino starting mid-day on Monday, Jan. 16, in response to reservoir levels and improving downstream conditions on the Russian River. No increased releases will occur at Warm Springs Dam at Lake Sonoma during this time.

Recent storms have significantly increased reservoir levels well into the flood control pool at Lake Mendocino for the first time since 2020. These storms have also sustained levels at, or close to, flood stage in communities along the Russian River. The river is now forecast to appreciably recede below flood stage. The high-flow release on Monday is intended to restore conditions capable of accommodating additional rainfall this season. This is the first time in nearly four years that a high-flow release is required to manage rising lake levels. Decisions to withhold high-flow releases during recent rains, and the current plan to manage reservoir level through Forecast Informed Reservoir Operations (FIRO) have been regularly coordinated with partners in Sonoma and Mendocino County to ensure the safety of downstream communities.

                                                                      Lake Mendocino                    Lake Sonoma

Coyote Valley Dam                 Warm Springs Dam

* Current level (in feet):                              749.8                                      437.0  

* Water stored (acre-foot):                         89.189                                   209,922

* Storage capacity (acre-foot):                  116,500                                 381,000

Significant high-flow releases of at least 3,000 cfs will be made at Coyote Valley Dam. The release is being timed to allow downstream river levels to recede while still allowing for as much time as possible to evacuate water from the dam prior to the next storm. Releases are expected to increase by approximately 1,000 cfs per hour and will be timed to coincide with decreasing river stage at downstream locations. Lake levels, river levels, as well as weather forecasts are constantly monitored by USACE. These conditions are subject to change based on updated forecasts.

For more information on timing, magnitude and duration of potential flood releases, please visit the California Data Exchange Center website at