Arroyo, Puerto Rico, United States [ZonaUrbana]; population was 8,763 in 1990; housing units was 2,877 in 1990; location is 17°58'N 66°4'W; land area is 1.01 square miles (645 acres); water area is 0.22 square miles (140 acres); FIPS code is 3927 [SourceCBP]