30296 -- U.S. ZIP code Municipality (1990): RIVERDALE, Georgia All ZIPs for this municipality (1990): 30274 30296 Population (2000): 21308 Housing Units (2000): 7464 Land area (2000): 12.736063 sq. miles (32.986251 sq. km) Water area (2000): 0.084476 sq. miles (0.218793 sq. km) Total area (2000): 12.820539 sq. miles (33.205044 sq. km) Located within: Georgia (GA) Location: 33.564711 N, 84.439875 W