J.A. McClure Michael Eberle 1984 An estimated 13,389 million gallons of water per day were used in Ohio in 1980, in four major categories of water use. Of this total, 12,645 Mgal/d (million gallons per day) were taken from surface-water sources whereas 744 Mgal/d was ground water. Totals for each category (in Mgal/d) were: thermoelectric power generation, 10,417; self-supplied manufacturing, 1,399; public water supplies, 1,432; and rural domestic and livestock, 141. Additional miscellaneous uses (irrigation, rural commercial, and non-manufacturing industrial) probably totaled about 300 Mgal/d. The five counties that led the state in total water use were: Jefferson, 2,620 Mgal/d; Lucas, 1,150 Mgal/d; Gallia, 1.086 Mgal/d; Cuyahoga, 1,085 Mgal/d; and Lorain, 991 Mgal/d. These counties, in the same order, were the top five surface-water users. (USGS) application/pdf 10.3133/wri844024 en U.S. Geological Survey, Water use in Ohio, 1980 reports