The data for Clay County are summarized in this water planning data fact sheet.
Clay County is located in northwest Iowa.
Wholesale and retail trade are the principal economic sectors, as measured by employee earnings. The county contains gently rolling hills, flat plains, the Little Sioux River Valley, and small drainage streams. The population of 17,585 is distributed in 10 incorporated cities and the surrounding rural areas. U.S. Highway 71 crosses the center of the county from north to south. Highway 18 crosses the county from east to west.