The Ohio River was chosen for a 316(b) case study because it is representative of large industrial rivers in the United States with cumulative impacts resulting from multiple CWIS. The river is a major waterway flowing southwest from Pittsburgh toward the Mississippi River. Throughout its entire length, the river consists of a series of navigation pools controlled by locks and dams maintained by the U.S. Army Corps of Engineers. The locks serve to pass barges from one pool to the next, and the dams regulate pool elevation. In addition to navigation, the Ohio River provides water for industrial and municipal uses, and is an important source of recreation, including pleasure boating, swimming, and fishing.