Ouachita -- U.S. County in Arkansas Population (2000): 28790 Housing Units (2000): 13450 Land area (2000): 732.450361 sq. miles (1897.037646 sq. km) Water area (2000): 7.181958 sq. miles (18.601184 sq. km) Total area (2000): 739.632319 sq. miles (1915.638830 sq. km) Located within: Arkansas (AR), FIPS 05 Location: 33.574007 N, 92.861447 W Headwords: Ouachita Ouachita, AR Ouachita County Ouachita County, AR