Riverdale, IA -- U.S. city in Iowa Population (2000): 656 Housing Units (2000): 285 Land area (2000): 1.788500 sq. miles (4.632193 sq. km) Water area (2000): 0.389690 sq. miles (1.009292 sq. km) Total area (2000): 2.178190 sq. miles (5.641485 sq. km) FIPS code: 67350 Located within: Iowa (IA), FIPS 19 Location: 41.535466 N, 90.467216 W ZIP Codes (1990): Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Riverdale, IA Riverdale