Grand Calumet River

The Grand Calumet River is a 13.0-mile-long (20.9 km) river that flows primarily into Lake Michigan. Originating in Miller Beach in Gary, it flows through the cities of Gary, East Chicago and Hammond, as well as Calumet City and Burnham on the Illinois side. The majority of the river's flow drains into Lake Michigan via the Indiana Harbor and Ship Canal, sending about 1,500 cubic feet (42 m) per second of water into the lake. A smaller part of the flow, at the river's western end, enters the Calumet River, and through the Illinois River ultimately drains into the Mississippi River.

Today, a large portion of the river's flow originates as municipal and industrial effluent, cooling and process water and storm water overflows. Although discharges have been reduced, a number of contaminants continue to impair the area. The river is among the country's most severely polluted, and as of 2015 was in the late stages of a major dredging project to remove thousands of tons of contaminated sediment and rehabilitate the river ecosystem.