Illinois River 20 miles (32 km) of its course, the Illinois is separated from the Mississippi River by only about five miles, by a peninsula of land that makes up Calhoun County. The Illinois joins the Mississippi near Grafton, approximately 25 miles (40 km) northwest of downtown St. Louis and about 20 miles upstream from the confluence of the Missouri River and the Mississippi. South of Hennepin, the Illinois River is following the ancient channel of the Mississippi River. The Illinoian Stage, about 300,000 to 132,000 years ago, blocked the Mississippi near Rock Island, diverting it into its present channel. After the
Muddy River (Nevada) Muddy River (Nevada) The Muddy River, formerly known as the Moapa River, is a short river located in Clark County, in southern Nevada, United States. It is in the Mojave Desert, approximately north of Las Vegas. The Muddy River is approximately long. It begins as a series of thermal springs in the Moapa Valley before continuing on its course to Lake Mead, where it drains into the northern arm of the lake near Overton, Nevada. Before the Hoover Dam's construction, the Muddy River flowed into the Virgin River. Near the town of Glendale the Muddy River collects the flow from