The flow of the Chicago River was famously reversed at the turn of the 20th century, officially opening on January 2, 1900. The original purpose was to protect the City of Chicago’s drinking water supply by diverting polluted water away from Lake Michigan. Engineers accomplished this by creating a new channel, the Chicago Sanitary and Ship Canal, which redirected the river’s flow toward the Des Plaines River. From there, the water joins the Kankakee River to form the Illinois River, eventually reaching the Mississippi River and, ultimately, the Gulf of Mexico.
This was an extraordinary engineering solution for Chicago, but not necessarily for the towns, communities, and wildlife downstream. Legal challenges soon followed from neighboring states and municipalities along the Great Lakes. The dispute reached the U.S. Supreme Court, which ruled in favor of Chicago regarding the downstream flow of pollution. However, the Court acknowledged concerns about excessive diversion of fresh water from Lake Michigan and its potential impact on the entire Great Lakes system. As a result, Chicago was required to control the volume of water diverted from the lake, leading to the construction of a system of locks.
For decades, pollution continued to flow downstream. But beginning in the 1970s, private community initiatives, supported over time by new public policies, sparked a long-term cleanup effort. Today, both the Chicago River and the Sanitary and Ship Canal have rebounded, supporting a diverse and growing wildlife population. Kayaking and river exploration have become common, and Chicago recently hosted its first open-water swim in the river in nearly a century.
As the waterways continue to recover, they are increasingly attracting new development—from parks and trails to residential and commercial projects. However, the historic name “Chicago Sanitary and Ship Canal” still evokes its past as an open-air sewer—hardly appealing for modern, nature-friendly redevelopment. A new name is currently under consideration, and public voting is underway. Log in and help shape the future of Chicago’s waterways by supporting a name that reflects renewal and ecological balance.