The water quality of the proposed LaFarge Lake, Wisconsin, was investigated using a version of the reservoir portion of the Water Quality for River-Reservoir Systems (WQRRS) ecological model. Although other water-quality constituents were simulated, the study concentrated on temperature, dissolved oxygen, and algae concentrations. Daily field measurements of phosphorus and nitrogen on the Kickapoo River were used in the simulations. Algal bioassays were also conducted on the Kickapoo River and surrounding impoundments. These assays indicated that essentially all of the soluble nitrogen and phosphorus in the river were in forms available for algal growth and that phosphorus was most likely to be the limiting nutrient in the proposed impoundment. The simulations indicated that LaFarge Lake probably will be thermally stratified from May through September.

The plan consists of a multiple-purpose lake for flood control, fish and wildlife production, and recreation. The dam-site would be located on the Kickapoo River about 1 mile north of La Farge, in Vernon County, southwestern Wisconsin. The dam would be an earth-fill structure with an overall length of 3,960 feet and a maximum height of 103 feet. The conservation or recreation pool at elevation 840 is designed to impound 33,000 acre-feet of water with a surface area of about 1,780 acres extending about 12 miles upstream. Local flood protection measures for the downstream communities of Gays Mills and Soldiers Grove have been approved; however these are separate projects which will be treated in separate environmental impact statements.