Kaskaskia River an alternative name for the Kaskaskia that persists in place names along the river, including Okawville, and in a major tributary, the West Okaw River. The Kaskaskia rises in east central Illinois in several farm ditches along the west side of Champaign. The headwaters of the river is just north of Interstate 74, where it is marked with a sign. The river flows south across rural Champaign and Douglas counties, then southwest across southern Illinois, past Vandalia. It joins the Mississippi from the north approximately northwest of Chester and south-southeast of St. Louis, Missouri. The watershed of the river encompasses
Big Black River (Mississippi) northern border of Claiborne County. The Big Black River and most of its tributaries are silt-filled. The rivers carry large amounts of suspended sediment, resulting mostly from agricultural runoff. These tributaries are slow-flowing muddy streams. However, some are swift-flowing with sandy bottoms. The Battle of Big Black River Bridge, fought during the Battle of Vicksburg, was part of the Vicksburg Campaign in the American Civil War. The size of the Big Black River Basin drainage area is . Its elevation varies from 50 to 650 feet (14 to 198 meters) above sea level. It is long and averages 22 to