Rush Lake, despite its massive 3,070 acre territory, is a lake in name only. Rather, it is the largest “Prairie Pothole marsh” east of the Mississippi River and second largest in the United States.
Though it is not considered an actual lake, it still produces a fair amount of northern pike and perch along with carp that reach the marsh via the Waukau carp pond.
The marsh has a yearly freeze-out that kills nearly 95% of the fish that remain in the lake throughout the winter. However, Rush Lake repopulates itself each spring thanks to the Waukau creek that runs into the Fox River as well as other feeder streams going in and out of Rush Lake.
Rush Lake in central Wisconsin, is used primarily for waterfowl conservation and a survey by Ripon College suggested that approximately 400 tons of lead were in the lake. The Rush Lake Restoration Project was established to not only help with the lead but also clean the murky lake and add more vegetation for the waterfowl.
Over 6,000 pounds of carp, both living and dead have been removed from Rush Lake and a 70% increase in vegetation was created, unfortunately not as bulrush had grown as expected and most of the vegetation has been dominated by three different species of cattails. The plan to eliminate the lead was not achieved due to budget constraints but water jetting drove the led deep into the mud and has greatly diminished the lead problem.