Lake San Marcos, California, United States [CDP]; population was 3,802 in 1990; housing units was 2,326 in 1990; location is 33°7'N 117°13'W; land area is 1.80 square miles (1,155 acres); water area is 0.16 square miles (100 acres); FIPS code is 39724 [SourceCBP]
