Most wells drilled in the valley bottoms and hillsides are adequate for a domestic supply. About half the wells drilled on hilltops and ridges are adequate for domestic needs. Deep wells penetrating more than 500 feet of sandstone may yield enough water for small utilities or industrial supplies. Water obtained from most wells is soft or moderately hard and contains noticeable amounts of iron. Salty water may be found in wells drilled 100 feet below the level of the principal valley bottoms. In the limestone valleys of western McCreary County, springs are occasionally found with flows as large as 100 gallons per minute. Throughout the county, however, most springs yield less than 5 gallons per minute.