Those three are the East Branch of the Rock River in Washington and Dodge counties, Upper Rock River watershed in Dodge and Fond du Lac counties, and Upper Crawfish River watershed in Columbia County. In addition two lakes and their subwatersheds are recommended for small-scale priority watershed project selection. They are Pike Lake in Washington County and Rock Lake in Jefferson County. At least 30 impoundments are in state or federal wildlife areas and are managed to promote migratory waterfowl use. None of the impoundments in the Upper Rock River basin were designed for flood control and the majority have very little flood storage potential.
Millponds are common in south and southwestern Wisconsin.
In the 1900s, many millpond dams were built or modified to provide hydropower. Over the decades, millponds have become important recreational and aesthetic resources to communities in which they exist. However, because of their special physical characteristics, millponds require intensive management to maintain moderate water quality. Long-term management solutions include dredging, dam removal, and lake management planning.