It is the source of drinking water for five million people.

The river became a primary transportation route for pioneers during the westward expansion of the early U.S. The lower Ohio River just below Louisville was obstructed by rapids known as the Falls of the Ohio where the elevation falls 26 ft in 2 mi restricting larger commercial navigation, although in the 18th and early 19th century its three deepest channels could be traversed by a wide variety of