Upper Mississippi River System Environmental Management Program. Definite ProjectReport (R-7F) with Integrated Environmental Assessment, Lake Chautauqua Rehabilitation and Enhancement, La Grange Pool, Illinois Waterway Mason County, Illinois

摘要

Lake Chautauqua is a 3,250-acre floodplain lake and wetland complex located inMason County, Illinois, within the LaGrange pool of the Illinois Waterway between river miles 124 and 128. The lake is formed by a 9-mile perimeter levee and is divided into an upper and lower lake by a cross dike. The area is presently managed by the U.S. Fish and Wildlife Service (USFWS) for migratory waterfowl as part of the Chautauqua National Wildlife Refuge. The goals for this project are the enhancement of waterfowl and fishery habitats. In order to accomplish these goals, the following design objectives were identified: (1) increase submergent and emergent vegetation (2) create flowing side channel and deepwater slough habitat; and (3) reduce sedimentation. Five alternatives were considered to meet the stated objectives: (A) no Federal action, (B) improve water control, (C) construct barrier islands, (D) excavate flowing side channel, and (E) raise levee elevations.