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
Olifants River (Southern Cape) the east and flows westwards between the Swartberg and Kammanassie mountains to its confluence with the Gamka River. The southern slopes of the Swartberg Mountains are drained by the perennial Groot River, Kango River, Grobbelaars River, Wynands River, Kansa River and Vlei River tributaries, which flow into the Olifants River. The Kammanassie River rises in the Outeniqua and Kammanassie mountains near Uniondale and joins the Olifants River upstream of Oudtshoorn. Olifants River (Southern Cape) Olifants River () is a river in the Klein Karoo area of the Western Cape, South Africa. It has its origins in the Traka and Kalkwal