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Home ›Mississippi River islands to reappear near Lynxville, WI
Many boaters and other river users may have noticed construction equipment once again in the Harpers Slough area, across from Lynxville, WI. Island construction continues this year in Pool 9 (River Miles 650-653) by Newt Marine Service of Dubuque.
Hydraulic dredging has gotten underway. For safety, river users are urged to stay away from construction activities, equipment and the hydraulic dredge pipe.
This $12 million project is located within the Upper Mississippi River National Wildlife and Fish Refuge, McGregor District. The project is funded through the U.S. Army Corps of Engineers Upper Mississippi River Restoration - Environmental Management Program, and was planned and designed cooperatively with the U.S. Fish and Wildlife Service, U.S. Geological Survey, and Iowa and Wisconsin Departments of Natural Resources.
Since the creation of Lock and Dam No. 9 in 1937, many of the natural islands in this area and the floodplain forests they support, have eroded and disappeared. This reduced habitat available for migratory birds. In addition to losing forest habitat, island loss allows more wind and wave action in backwaters, keeping sediment suspended (turbidity). The suspended sediment in turn makes it difficult for sunlight to penetrate the water and reach aquatic plants. This results in the loss of valuable aquatic plant beds that migrating waterfowl and fish use for food and cover.
The islands will be built using material dredged from the main channel and from the Harpers Slough area backwaters. To prevent the new islands from eroding, rock will be placed along sections of shoreline and vegetation will be planted. The islands will help protect and enhance existing islands and aquatic vegetation in the Harpers Slough area, and dredging the backwaters will create deeper holes for fisheries overwintering habitat. Trees will be planted on the higher portions of islands to improve the floodplain forest. Construction is scheduled to be completed in 2018.
When the Harpers Slough Islands project is completed (see accompanying map) there will be seven new islands and overwintering fish habitat. This project will provide many recreational opportunities for the public, as well as restored habitat for migratory birds, turtles, frogs, fish, mussels, beaver, mink, and otter.