Upper St. Clair, Pennsylvania, United States [CDP]; population was 19,692 in 1990; housing units was 6,806 in 1990; location is 40°20'N 80°5'W; land area is 9.76 square miles (6,243 acres); water area is 0.01 square miles (5 acres); FIPS code is 79312 [SourceCBP]
