Trentwood, Washington, United States [CDP]; population was 4,060 in 1990; housing units was 1,468 in 1990; location is 47°42'N 117°13'W; land area is 1.79 square miles (1,145 acres); water area is 0.01 square miles (8 acres); FIPS code is 72310 [SourceCBP]