The Chicago River
Chicago River, a river in downtown Chicago. It is formed by the meeting of the North Branch and South Branch of the Chicago River, about one mile (1.6 km) west of Lake Michigan. The river flowed east into the lake until 1900, when the Chicago Sanitary and Ship Canal was completed and locks were built at the river's mouth, in order to carry sewage away from the lake. The river and canal are part of the waterway system that links Lake Michigan with the Mississippi River.