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
Big Sandy Creek (Illinois) two streams combine shortly before discharging into the Illinois River opposite the hamlet of Montezuma, Illinois. Sand discharged by the alluvial creeks may have helped form McEvers Island, a silt island in the Illinois River just below the mouth of the creek. Big Sandy Creek (Illinois) Big Sandy Creek, often called the "Big Branch", is a tributary of the Illinois River in central Illinois. It drains a large portion of southwestern Morgan County and southern Scott County. The drainage of Big Sandy Creek includes Lake Jacksonville and the county seat of Scott County, Winchester, Illinois. Most of the Big Sandy