Des Plaines River

About

Des Plaines River, Illinois — 1673 Jolliet and Marquette. The Des Plaines first entered the written record in 1673, when Jolliet and Marquette crossed the Chicago Portage — a six-mile carry between the Des Plaines and the Chicago River that linked the Great Lakes to the Mississippi watershed. Long before that, the same corridor served the Potawatomi and Miami, for whom the portage was the western half of a strategic overland route between the two basins. It was the only waterway gap in the Great Lakes–Mississippi divide, and that single geographic accident shaped North American trade for centuries.

The river's name has a wandering history of its own. An 18th-century cartographer labeled it "Plein" for its high water, and the word drifted through Au Plaine, Aux Plaine, and O'Plain before settling into the French "Des Plaines" the river carries today. The river is also the namesake of the city of Des Plaines, Illinois.

Engineering reshaped the corridor in the canal era. The Illinois and Michigan Canal, completed in 1848, connected the Great Lakes to the Mississippi and made the Des Plaines a principal waterway along its route — a role still visible today in the I&M Canal corridor between Isle a la Cache and Channahon. In 1900, the Chicago Sanitary and Ship Canal diverted the river's flow away from Lake Michigan, a reversal that would only be undone by later canal work.

The watershed also fed the timber economy. From the 1830s through the 1920s, the Des Plaines basin was logged to supply the regional timber industry and the railroad expansion of the 1860s through 1910s, worked by local sawmills, logging drives, and downstream lumber operations. Large-scale cutting ended as the old-growth stands were exhausted around 1910 and state forestry conservation took hold. Hydrologists arrived in the same period: USGS surveys in the 1870s–1890s and gauging stations established from the 1880s onward produced the first comprehensive studies of the river's flow, later joined by Clean Water Act assessments after 1972.

Modern history on the Des Plaines is a story of recovery. In the winter of 2011–2012, the Forest Preserves of Cook County, working with the U.S. Army Corps of Engineers and the Illinois Department of Natural Resources, began removing the low-head dams that had long choked the river's flow. The Metropolitan Water Reclamation District and the Forest Preserves partnered on further restoration by 2019, improving water quality and riparian habitat. Between 2016 and 2025, the Army Corps of Engineers worked to remove PCB-contaminated sediment from the river's lower 16 miles.

For paddlers, the river today is a corridor of moving water more than a highway. Its riffle character and 300–1,200 optimal window suit flatwater and gentle current rather than whitewater. The Des Plaines River Trail, managed by the Lake County Forest Preserves, follows the upper river, and preserve-lined reaches carry canoeists from Libertyville down to Riverside and on toward the I&M Canal country near Channahon. What was once the continent's most consequential portage is now valued as a recovering ribbon of green through metropolitan Illinois.