East Merrimack, New Hampshire, United States [CDP]; population was 3,656 in 1990; housing units was 1,696 in 1990; location is 42°52'N 71°29'W; land area is 3.02 square miles (1,934 acres); water area is 0.30 square miles (195 acres); FIPS code is 21780 [SourceCBP]