The U.S. Army Corps of Engineers’ Upper Mississippi River Restoration Program includes studies and projects in the Upper Mississippi River system north of Cairo, Illinois. The system includes the Illinois River. This program, authorized by Congress in 1986, emphasizes habitat rehabilitation and enhancement projects and long-term resource monitoring. The habitat project component includes dredging backwater areas and channels, constructing dikes, creating and stabilizing islands and controlling side channel flows and water levels.
The hydrology in the area has changed significantly, driven in part by change in land use and climate. The proposed project aims to improve habitat for aquatic vegetation and migratory waterfowl by providing water level management capabilities that target management goals of the refuge.
Dissolved oxygen is essential for a healthy fisheries habitat. Dissolved oxygen depletion is a problem in the study area in summer and in winter due to a variety of reasons. Conway Lake is relatively shallow with abundant aquatic vegetation. During the winter, excessive water enters Phillipi Lake through openings that are eroding, creating unsuitable habitat conditions for overwintering backwater fish. Shore Slough has less than optimal fish habitat conditions as a result of sedimentation and the high flows from Phillipi Lake.
Harpers Slough area is a 4,150-acre backwater area located primarily on the Iowa side of the Mississippi River in Pool 9, about 3 miles upstream of Lock and Dam 9. The project will protect five existing islands and construct an additional seven islands using material from the backwater and main channel. The project will slow the loss of existing islands, reduce the flow of sediment-laden water into the backwaters, reduce turbidity and increase the diversity of land and shoreline habitat.
Lower Pool 10 Islands restoration project is a side channel/island complex located on the Iowa side of the Mississippi River navigation channel in Pool 10, about one mile upstream from Lock and Dam 10 in Guttenberg, Iowa. The proposed project goals include protecting and restoring island complexes in this 1,000 acre area that would restore and enhance quality habitat for native and desirable species by reducing suspended solid concentrations and reducing wind fetch.
McGregor Lake is a 200-acre backwater lake in Pool 10 of the Mississippi River near Prairie du Chien, Wisconsin. The proposed project could include various features, such as dredging the lake, restoring or strengthening the barrier islands and constructing small islands within the lake to reduce wave action. It could also improve adjacent forest habitat.
Much of the floodplain forest in the Reno Bottoms project area has been declining in coverage over the past several decades. Current Pool 9 water management and flow through the Lock and Dam 8 embankment have shifted the floodplain forest distribution to higher elevations than pre-impoundment conditions. Without active management, floodplain forest in the Reno Bottoms project area is likely to continue to degrade. The proposed project goals include protecting, maintaining and restoring floodplain hardwood forests to levels that are sustainable. The 14,000 acre Reno Bottoms area is located within the Upper Mississippi River National Wildlife and Fish Refuge in Houston County, Minnesota and Allamakee County, Iowa and is in Pool 9 between river miles 671‒682.