In the nineteenth century the U.S Army Corps of Engineers began scouring a reliable 9-foot navigation channel in the Middle Mississippi River south of St. Louis to the Ohio River. Wing dikes, set perpendicular to the shore, sped up the current and forced the river to scour and from the river bed, which was caught between the wing dams in the dike field. The Jefferson Barracks dike field is a good illustration of this process.
In addition the engineers built closing dam across side channels to keep the river from adopting side channels as its main channel. The side channels silted in and the adjacent island became glued to the main land. By the Flood of 1993 there were three remaining side channels on the Middle Mississippi. Fish lost quiet habitat for breeding and feeding.
The flood highlighted the need to provide habitat for fish and wildlife in the Middle Mississippi. The following year folks from the Applied Engineering Center at the St. Louis District of the Corps of Engineers, and biologists from the U.S. Fish and Wildlife Service began experimenting with ideas that might open up the remaining side channel for fish habitat. They used a table-top model of the Middle Mississippi to test ways to move water and sediment and create habitat, using notches in closing dams to create side channels along dike fields, and chevron dikes and hard point to scour deep holes for fish. Finally, they developed the Mississippi River Side Channel Rehabilitation and Conservation Project with the aim of restoring the 23 remaining side channels in the Middle Mississippi.
In October 2008 the US Forest Service, the US Fish and Wildlife Service, the US Army Corps of Engineers, Ducks Unlimited, the Illinois DNR, The Nature Conservancy, the US Geological Service, the American Land Conservancy, the Missouri Department of Conservation, the Natural Resources Conservation Service, the Southwestern Illinois Resource Conservation and Development and others established the Middle Mississippi River Partnership. The purpose of the inclusive organization was to develop a vision of what the Middle Mississippi River should look like in the future and how it should foster the enhancement of fish and wildlife.
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