Lake Mendocino is a large reservoir in Mendocino County, California, northeast of Ukiah. It covers 1,922 acres (7.78 km2) and was formed by the construction of Coyote Valley Dam in 1958. The lake and dam provide flood control, water conservation, hydroelectric power, and recreation. The dam also includes a fallout shelter built during the Cold War era to protect against the radiation from nuclear attacks from the Soviet Union.