Big Muddy River Big Muddy River The Big Muddy River is a river in southern Illinois. It joins the Mississippi River just south of Grand Tower. The Big Muddy has been dammed near Benton, forming Rend Lake. The Big Muddy has a mud bottom for most of its length. The Big Muddy drains a watershed. In 1995, water quality was assessed as "fair" to "good". Pollution sources include agricultural practices, mining and municipalities. The watershed of the Big Muddy was covered by the Illinoian Glacier about 300,000 to 132,000 years before present. The Big Muddy basin formed after the retreat of that glacier.
Vermilion River (Illinois River) Vermilion River (Illinois River) The Vermilion River is a tributary of the Illinois River in the state of Illinois, United States. The river flows north, in contrast to a second Vermilion River in Illinois, which flows south to the Wabash River. The Illinois and Wabash rivers each have a tributary named the Little Vermilion River as well. The north-flowing Vermilion River and the south-flowing Middle Fork Vermilion River run on what is close to a straight line between Oglesby and Danville. In presettlement times, the two rivers drained an upland marsh near Roberts. It is possible that early settlers regarded