The long memory of the Chicago River

**Margaret Frisbie** and her colleagues at **Friends of the Chicago River** are documenting the return of native wildlife to the **Chicago-Calumet river system**. After nearly **50 years** of restoration work, species such as river otters and channel catfish are thriving in waters once considered biologically dead.

For a century, the South Fork of the river was known as Bubbly Creek, so named for the methane gas that rose from decomposing animal remains dumped by the city’s packing houses. In 1900, the city’s solution to its waste was a feat of brute force: reversing the river’s flow to pull sewage away from the lake. The waterway became a plumbing fixture, a grey expanse of industrial transit where fewer than **10 species** of fish could survive. It was a place where the city turned its back, a drainage ditch of such profound neglect that its recovery seemed a biological impossibility.

The restoration did not happen by chance, but through the patient, unglamorous application of law and engineering. Following the 1972 federal Clean Water Act, the city began the **Tunnel and Reservoir Plan**, an immense network of deep underground conduits designed to capture overflow before it could reach the channel. Frisbie, who has led the Friends of the Chicago River through decades of advocacy, understood that cleaning the water was only the first step. To bring back life, the river needed to regain its character as a habitat.

In 2014, the organization co-invented and installed over **400 channel catfish nesting cavities**. These were rough-textured, heavy tubes designed to mimic the sunken, hollowed-out logs that had long ago rotted away when the river was dredged. Placed by hand into the dark water, these artificial nurseries provided the seclusion the *Ictalurus punctatus* needed to spawn. Today, the catfish are abundant, joined by virile crayfish and little brown bats that flicker through the twilight above the banks.

The Chicago-Calumet river system is one of the nation’s greatest comeback stories, and it’s teeming with wildlife.

Through the "Wild River Resolutions" campaign, Frisbie is marking each month of 2026 with a different species that has reclaimed its place in the watershed. The work is far from finished, but the river system is now cleaner and more accessible than it has been in over **150 years**. It is a quiet triumph of human decency over industrial convenience—a reminder that a city can, with enough time and care, remember its own nature.