Twitchell Dam

The Environmental Defense Center has always prioritized the protection of endangered Southern California steelhead, a keystone species which used to number in the tens of thousands across our region. The Twitchell Dam, located east of Santa Maria on the Cuyama River, has been identified as a major problem, preventing steelhead from reaching their historic breeding grounds. The Dam limits the timing and quantity of flow in the main stem of the Santa Maria River, preventing steelhead from reaching the Sisquoc River which is the most important spawning tributary within the stream network.

In 2017, EDC filed a state lawsuit on behalf of our client Los Padres ForestWatch, in partnership with San Luis Obispo Coastkeeper, to compel the Santa Maria Valley Water Conservation District (District) to modify its operations of the Dam to ensure sufficient water is available to protect this endangered species while replenishing groundwater. In 2019, we filed another lawsuit, this time in federal court against the District and the U.S. Bureau of Reclamation, on the grounds that they are harming steelhead in violation of the Endangered Species Act.  Both cases are pending in court.