The Falls of the Ohio National Wildlife Conservation Area is a national, bi-state area on the Ohio River near Louisville, Kentucky in the United States, administered by the U.S. Army Corps of Engineers. Federal status was awarded in 1981.

Overview

The area is located at the Falls of the Ohio, which was the only navigational barrier on the river in earlier times. The falls were a series of rapids formed by the relatively recent erosion of the Ohio River operating on 386 million-year-old Devonian hard limestone rock shelves. Louisville, Kentucky, and the associated Indiana communities — Jeffersonville, Clarksville, and New Albany — all owe their existence as communities to the falls, as the navigational obstacles the falls presented meant that late 18th Century and early to late 19th Century river traffic could benefit from local expertise in navigating the drop made by the river over a distance of two miles (3 km). In its original form, the falls could be characterized more as rapids extending over a length of the river, than as a point-like discontinuity in a river such as Niagara Falls. Still, the falls provided a singular, dramatic and daunting obstacle to navigation on this important inland waterway.

The first locks on the river were built on a bypass canal there to provide year-round navigation on the river. The falls were then largely covered by the McAlpine Locks and Dam, built by the Army Corps of Engineers. The taming of the Ohio River at the falls, with the attendant reduction in local flow velocity has of late led to the covering over of the fossil beds by large and increasing quantities of low-velocity effluvia: although an impediment to viewing of the fossils, this action serves to protect the portions of the falls covered over by sediment and therefore temporarily immune to direct weathering. However, a significant area of the fossil-rich Devonian limestone rock is still left exposed, and is accessible to visitors today. The best time for visitation is during the low water season of the Ohio River between August and October. Removal of fossils is prohibited.

Because of the shallowness of the river at the Falls, it was a favorite crossing point for bison in pre-settlement times, and was an easy crossing point for Native Americans.

In 1990, a section of the area in Indiana became the Falls of the Ohio State Park. An interpretive center is open throughout the year.

Geology

The rock unit in which the falls are formed is referred to as the Jeffersonville Limestone. The limestone formed approximately 387 to 380 million years ago during the Emsian Age (in the latest part of the Early Devonian Period) and the Eifelian Age (Middle Devonian). The exposure is rather unique - large and diverse tabulate corals and rugose corals are exposed in life-like positions. Brachiopods and bryozoans are also present, as are gastropods (snails).

During the Devonian Period, the region lay at the bottom of a shallow inland sea about ten degrees north of the equator in the supercontinent of Euramerica.

Unusual wildlife finds

On August 7, 2006 a man fishing for catfish at the Falls caught an octopus that measured six feet from the tips of its tentacles. This odd occurrence was reported in the Louisville Courier-Journal that noted that other strange and out of place animals like alligators, crocodiles and piranha-like tropical fish had also been found at the Falls of the Ohio. Zachary Treitz, a 21-year-old Louisville college student, admitted he had put the octopus there after purchasing it dead from a local seafood shop for a film project.