According to the U.S. Census Bureau , the county has a total area of 766 square miles ( 1,980 km2 ) , of which 720 square miles ( 1,900 km2 ) is land and 46 square miles ( 120 km2 ) ( 6.0 % ) is water .
The county has a total area of 766 square miles ( 1,983.9 km2 ) .