Castaic lake is located at the north end of Los Angeles County and is part of the California state aqueduct system, providing water to Southern California. Castaic Lake is made up of two bodies of water, the upper lake and the Castaic Lagoon. The upper lake covers 2,235 acres with a surface elevation near 1,500 feet. The Castaic Lagoon is located to the immediate south of the lake and covers 197 acres.