Water level drawdown to begin at Mondeaux Flowage on Sept. 30

SUBMITTED

The Chequamegon-Nicolet National Forest will reduce water levels on the Mondeaux Flowage in Taylor County, Wisconsin, starting the week of September 30, 2024. The drawdown is expected to be completed the by the first part of November 2024.

A 2024 survey and data review, conducted by the Forest Service, Wisconsin Department of Natural Resources, and Mondeaux Lake Association, determined that thick aquatic vegetation is adversely affecting fishing and boating activities in the flowage. Thick aquatic vegetation in shallow flowages hampers recreational activities. It also provides excessive hiding cover for panfish, resulting in high fish numbers and corresponding small sizes. Thick aquatic vegetation can also decompose under ice cover, resulting in low winter oxygen levels.

“Reducing water levels in the winter concentrates overabundant, slow-growing panfish and results in less hiding cover in the following season,” said USDA Forest Service Fish Biologist Nicholas Berndt. “This increases predation, reduces overabundance, and helps to increase panfish growth rates and size structure.”

The water level in the 411-acre Mondeaux Flowage will be released at a rate of approximately three to four inches per day to reach a final level of 4 to 4.5 feet lower than the present level. The drawdown will be gradual enough to prevent shoreline damage and lessen the potential for stranding aquatic organisms prior to freeze-up. The maximum depth of the flowage at current levels is 10 feet.

The Chequamegon-Nicolet National Forest will begin increasing water levels in the flowage starting around March 1, 2025. Refilling is expected to be complete by April 1, 2025. There have been periodic drawdowns on the Mondeaux Flowage since the winter of 1971-1972 with the most recent in the winter of 2017-2018.