Chicago

Chicago, river, north-eastern Illinois, chiefly within the city of Chicago. The river, formerly emptying into Lake Michigan and now an outlet for the lake, flows west from the lake, separating into two branches about 1.6 km (1 mi) inland. The normal direction of flow into Lake Michigan was reversed during construction of the Chicago sewage disposal system, the principal feature of which is the Chicago Sanitary and Ship Canal. The canal extends from a point on the South Branch of the river to a point on the Des Plaines River at Lockport, Illinois, providing an outlet for effluent from the purification plants of the Chicago Sanitary District. Together with the canal, the river forms a link of the Illinois Waterway, a system that joins the Great Lakes to the Gulf of Mexico via the Illinois and Mississippi rivers. The Chicago River is also connected to the Illinois River by the historic Illinois and Michigan Canal, which extends from the South Branch, at a point in the Bridgeport section of Chicago, to La Salle, Illinois, nearly 160 km (100 mi).