The Rainwater Basin Wetland Management District (WMD) staff manages 61 tracts of wetlands, totaling 23,059 acres scattered over more than 14 counties in southeastern Nebraska. Each of the 61 areas, known as waterfowl production areas (WPA), is located in a geographic area known as the Rainwater Basin. The name "Rainwater Basin" originates from the geologic formation of large, wind-blown shallow depressions, which become flooded after rain and snow melt. WPAs are managed to provide resting stops for millions of migratory water birds. Upland areas are managed for grassland species. WPAs provide excellent recreational opportunities, including hunting, photography, and bird watching.