Part of the U.S. Army Corps of Engineers' Upper Mississippi River Restoration Program, the site is a side channel/island complex located on the Wisconsin side of the Mississippi River navigation channel in Pool 9, about five miles downstream from Lansing, Iowa. The site is in the Upper Mississippi River National Wildlife and Fish Refuge. Many of the natural islands bordering the navigation channel and extending into the backwater have eroded and many are disappearing. Erosion from wave action and main channel flows is reducing the size of the wetland complex, resulting in the loss of aquatic vegetation and the shallow protected habitats important for the survival of many species of fish and wildlife.
The project has restored and helped stabilize islands to protect the area from large wind fetches. Breached areas were stabilized using rock sills, and partial-closing structures were constructed to reduce the effect of main channel flows. Material to restore the island complex was dredged from the immediate vicinity to provide additional deepwater fish habitat benefits. The project has provided both fish and wildlife benefits by creating a “shadow” effect behind and downstream of the islands.
About 820 acres of backwater habitat was directly affected.
The project was turned over to the U.S. Fish and Wildlife Service in the summer of 2015 to operate and maintain. A project dedication ceremony was held on May 13, 2016 in Ferryville, Wisconsin.
The Capoli Slough Habitat Rehabilitation and Enhancement project was implemented under the authority of the Upper Mississippi River Restoration program. This program was authorized by Section 1103 of the Water Resources Development Act of 1986 and reauthorized by the Water Resources Development Act of 1999.
The project was constructed as part of a cooperative effort of the U.S. Army Corps of Engineers, the U.S. Fish and Wildlife Service, the Wisconsin and Iowa Departments of Natural Resources and local interests.
Project design and construction costs were 100 percent Federal, because the project is located on lands managed as a national wildlife refuge. Operation and maintenance costs are 100 percent Federal, a responsibility of the U.S. Fish and Wildlife Service.
Total project cost $ 9.4 million