Big Muddy River The Big Muddy was not covered by the Wisconsin Glacier, about 70,000 to 10,000 years before present. However, during the melting of that glacier, the level of the Mississippi River was much higher. Water backed up into the Big Muddy Basin, forming a lake much like the artificial Rend Lake but covering a larger area. The ancient lake silted in, forming a flat bottom. After the melting of the Wisconsinan glacier, the level of the Mississippi dropped, allowing the lake to drain. A new channel formed within the old lake bed. This channel meandered in the flat bottom of the
Fox River (Illinois River tributary) and a spillway to the east. A small dam is present just a few miles south in downtown Rochester. The river then flows unobstructed through Burlington, where it joins the White River, and on to Wilmot. This is a popular and picturesque day-canoe trip never straying far from the road, but often just out of sight of it. Flooding is common on this section of the river, especially near Wheatland to the border. The river enters Illinois where it widens into a large area of interconnected lakes known as the Chain O'Lakes. Fox Lake is the largest village in this