Multi-State Multi-Agency Efforts to Restore Floodplain Ecosystems of the Mississippi and Illinois Rivers

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Despite many modifications, the Upper Mississippi and Illinois Rivers remain a great national treasure. Congress has designated the Upper Mississippi as both a nationally significant ecosystem and a nationally significant commercial navigation system under the Water Resources Development Act of 1986 (WRDA). Concerns over impacts to fish and wildlife resources within the both of these waterways initiated funding under the WRDA for a comprehensive environmental management and restoration plan for the Upper Mississippi and Illinois rivers, titled the Upper Mississippi River Environmental Management Program (EMP). Under this program, forty eight instream and floodplain habitat improvement projects have been completed or are in construction phase since the programs beginning. Through multi-state multi-agency partnerships, over 100,000 acres of formerly degraded floodplain, backwater, and island habitat, caused by past development of floodplains, levee building, and channelization, has been improved throughout the Upper Mississippi River Basin . Lake Chautauqua , a once high quality floodplain habitat within the Illinois River consisting of shallow water nurseries and foraging habitats important to fish and migratory waterfowl, was targeted for habitat rehabilitation by the EMP program.

Where is the project located?

Lake Chautauqua is located within the La Grange navigation pool of the Illinois River , Mason County , central Illinois , USA

When and why was this project initiated?

Habitat rehabilitation of Lake Chautauqua was initiated in 1992 by the Army Corps of Engineers, Rock Island District. Prior to project initiation, suspended sediment carried by flood events in the Illinois River decreased water depths and degraded habitat necessary for over-wintering of fish and growth of submerged aquatic plants important to migratory waterfowl. This project was completed in 1998.

What types of activities were performed?

Project activities over 3,250 acres included increases in water depths of open pool areas by hydraulic dredging, lake bed sediment consolidation through constructed dewatering channels, and water quality/quantity control structures. Intensive monitoring of waterfowl, vegetation, and fish communities within affected areas has continued from project initiation through present. Participating agencies during the construction and monitoring phases of this project include the Army Corps of Engineers, U.S Fish & Wildlife Service, Illinois Department of Natural Resources, and the Illinois Natural History Survey.

Why is this a notable project?

Extensive degradation of remaining high quality floodplain habitats and the importance of maintaining active navigation routes by channelization, levee building, and dredging is a complex issue within the Midwest . The large amount of effort employed by numerous federal, state, and NGO agencies to restore and monitor Lake Chautauqua habitats is extremely promising and shows inter-agency goals of Midwest large river sustainability for recreational, navigation, and wildlife purposes.