The Los Vaqueros Watershed consists of 18,500 acres of protected watershed land surrounding the 1,900-acre Los Vaqueros Reservoir. The reservoir stores up to 160,000 acre-feet of water for Contra Costa Water District customers in central and eastern Contra Costa County. The Los Vaqueros Dam is under the jurisdiction of the State of California Division of Safety of Dams. Learn more about our Dam Safety Program.