Jim Chapman Lake (also known as Cooper Lake) is a 19,305 acre impoundment that provides water supply storage for the North Texas Municipal Water District, the Sulphur River Municipal Water District, and the city of Irving. This water supply storage exists in the conservation pool between elevations 415.5 ft msl and 440.0 ft msl.  The water intake structure is located on the South shore of the lake, which pulls anywhere from 2.0 million gallons per day of water in the winter months to 5.0 million gallons per day in the summer months.