Jefferson -- U.S. County in Nebraska Population (2000): 8333 Housing Units (2000): 3942 Land area (2000): 573.014992 sq. miles (1484.101954 sq. km) Water area (2000): 2.480699 sq. miles (6.424980 sq. km) Total area (2000): 575.495691 sq. miles (1490.526934 sq. km) Located within: Nebraska (NE), FIPS 31 Location: 40.162013 N, 97.145107 W Headwords: Jefferson Jefferson, NE Jefferson County Jefferson County, NE