Lake Wissota Improvement and Protection Association


2009 Plant Study

“Lake Wissota is an impoundment that was created in 1917 with the creation of a hydroelectric dam on the Chippewa River. Lake Wissota was historically lowered 10-15 feet every winter in anticipation of the spring thaw and to sustain power-production. This drawdown was maintained for several weeks annually (Chippewa River Settlement Team, 2001). The Lower Chippewa River Settlement Agreement was established in 2001 as part of the FERC licensing procedure. One issue raised was concern over the effects the winter drawdowns were having on the Lake Wissota ecosystem. As outlined in this agreement, Lake Wissota drawdowns were reduced from the 10-15 ft norm to a 3 ft maximum maintained for a maximum of seven days. Given the documented effects of extended periods of drawdown it is expected that the reduction in the drawdown resulted in a change in the aquatic plant community of Lake Wissota.

A survey of the aquatic plants in Lake Wissota was conducted during August of 1989 and August of 1990 by Water Resources staff from the Western District Wisconsin Department of Natural Resources office (WDNR). The study was funded by the WDNR and Northern States Power Company (now Xcel Energy) in anticipation of re-licensing of the Lake Wissota dam scheduled to occur in 2000. The purpose of this survey was to provide baseline aquatic plant information needed to make management decisions for fish and wildlife habitat improvement and water resource regulations.

The 1989/90 survey was repeated in 2005 (Heuschele, 2006) and 2009 by researchers from the Beaver Creek Reserve Citizen Science Center to assess changes that have occurred in the aquatic plant community as a result of the reduction of the winter drawdowns. These studies were funded by the Xcel Energy Natural Resources Fund and WDNR Lake Management Planning Grants. The results of comparisons of data from all three years’ studies are presented in this report.”