NOTICE OF AVAILABILITY: Draft Environmental Assessment for Coyote Valley Dam-Lake Mendocino Water Control Manual Update

In accordance with the National Environmental Policy Act (NEPA) of 1969 (42 U.S.C. § 4321 et seq), as amended, the United States Army Corps of Engineers, San Francisco District (USACE) has prepared a Draft Environmental Assessment (EA) for the Coyote Valley Dam (CVD)-Lake Mendocino Water Control Manual (WCM) Update.

Current operations of the CVD-Lake Mendocino are governed by the existing WCM which was revised in 1986 and last updated in 2011 without the benefit of modern weather and streamflow forecasting information. The draft EA provides an evaluation and description of the proposed action to update the CVD-Lake Mendocino WCM to allow discretionary encroachment into Flood Control Space based on the 5-day deterministic streamflow forecasts provided by the National Weather Service as per Lake Mendocino Forecast-informed Reservoir Operations (FIRO) procedures that have been vetted and tried through a series of USACE-approved major deviations during Water Years 2019, 2020 and 2021-2026. The encroachment would provide water storage of up to 11,650 acre-feet into the flood control space, and USACE reservoir operators retain full operational control and authority.

The USACE is providing this notice of availability of the draft EA for public review and comment. The public comment period will run until August 16, 2025 and feedback is invited. The Draft EA and associated appendices can be accessed by navigating your web browser to the website below and clicking on the “Draft Environmental Assessment” under the title called “Coyote Valley Dam-Lake Mendocino Water Control Manual Update” in the left-hand side of the page to open the report document.  

Website: https://www.spn.usace.army.mil/Missions/Environmental/