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
Vermilion River (Illinois River) these as a single river that flowed in two directions. It is also possible that, in early settlement times, these rivers formed a canoe route between the Illinois River and Wabash River, with a portage through the marshes near Roberts. This may explain why the two rivers have the same name. The north-flowing Vermilion flows in a northerly direction from its origin in Livingston and Ford counties in north central Illinois, eventually emptying into the Illinois River, near Oglesby. Perhaps it is best known for its stretch of whitewater between Lowell and Oglesby, Illinois, which is one of few found