CHICAGO – Every year, the plumbers’ union dyes it green. The Dave Matthews Band once infamously dumped 800 pounds of poop into it. And at least one section became known for the bubbles produced by toxic sludge on its floor.
The Chicago River has had a choppy history amid the city’s rise into a metropolis. But for the first time in nearly a century, city officials are inviting swimmers back in for the inaugural Chicago River Swim, a race on Sept. 21 aimed at raising money for amyotrophic lateral sclerosis, or ALS, research. ALS is also known as Lou Gehrig’s disease.
Mayor Brandon Johnson, who OK’d the swim in August, praised the upcoming event in a statement.
‘The return of the Chicago River Swim marks a major victory for our city ‒ a testament to decades of hard work revitalizing our river,’ Johnson said. ‘This event is a celebration of Chicago’s progress and a brighter, more inclusive future.’
According to race organizers, A Long Swim, the swim is the first of its kind in 98 years. Around 400 swimmers, including Olympians, will compete in either 1- or 2-mile races that will pass architectural icons from Marina City, a set of midcentury corncob-shaped apartment buildings from the 1960s, to Merchandise Mart, a massive Art Deco building that was the largest in the world when it opened in 1930. Swimmers will also pass beneath several of Chicago’s emblematic bridges.
The race is organized by A Long Swim, a charity that raises money for ALS research by staging open water swims throughout the United States, including between Nantucket and Martha’s Vineyard in Massachusetts and between the islands of Molokai and Oahu in Hawaii. Chicago-area native Doug McConnell founded the organization in 2011. The 67-year-old lost both his father and sister to the neurodegenerative disease. His organization has raised $2.5 million for ALS research.
McConnell said the Chicago River swim is inspired by a similar ALS swim in the canals of Amsterdam that has been running since 2011 and which raised around $2 million in the 2025 swim alone. He hopes the Chicago swim becomes a similar marquee event.
‘Chicago does big events really well, and we just want to be on that list,’ said McConnell, naming other big charity races, including the Amsterdam swim and the Boston and Chicago marathons. ‘We think it’s a path to a cure for that horrible disease.’
The race comes after decades of efforts to clean up the river, which served for generations as the industrial powerhouse’s open sewer.
In launching the race, Chicago becomes the latest major city to reopen its waters. Other cities that have done so in recent years include Paris, which opened the Seine for the Olympics and then kept it open for recreational swimmers; Cincinnati, which has been holding the Great Ohio River Swim since 2007; and Portland, Oregon, with the 11-mile Bridge Swim. A Long Swim also held a 29-mile race around Manhattan Island in 2014.
Among the swimmers competing in the Chicago swim are American Olympians Olivia Smoliga, a gold medalist at the 2016 Games in Rio de Janeiro, and Natalie Hinds, a bronze medalist at the 2020 Games in Tokyo.
Winners get trophies. Proceeds from the race also go toward teaching Chicago-area children to swim, according to organizers.
Determinations about whether the water is considered safe or not are based on readings of the concentrations of pollutants, including E. coli and fecal matter.
Race organizers said that they are conducting testing at eight different points along the race course. So far, all tests have come at between 200 and 600 CCE, a measure of bacteria levels, organizers said.
Below 1,000 CCE is considered safe, 1,000 to 10,000 CCE is considered risky for immunocompromised swimmers, and above 10,000 CCE is considered unsafe.
An open sewer
The Chicago River’s arrival at a point where it’s considered safe enough to swim marks a complete transformation ‒ or so city leaders hope ‒ from its industrial past.
As Chicago rose from being a trapping village on Lake Michigan into the ‘hog butcher of the world,’ as local poet Carl Sandburg put it in a 1914 poem, the river was essential to local industry.
But it also became a dumping ground. Upton Sinclair described a section known as Bubbly Creek in ‘The Jungle’ as a ‘great open sewer.’
‘The grease and chemicals that are poured into it undergo all sorts of strange transformations,’ Sinclair writes. ‘It is constantly in motion, as if huge fish were feeding in it, or great leviathans disporting themselves in its depths.’
According to race organizers, the river only briefly served the sporting purpose they hope it will again.
The Illinois Athletic Association hosted swim races in the river starting in 1908 that drew as many as 100,000 spectators, according to race organizers. But by the late 1920s, industrial and human runoff accumulated in the river to the point that it was no longer considered safe for swimming and the races were called off.
River becomes a playground
Environmental experts largely credit the Clean Water Act of 1972 for restoring the river from what it had become by the middle of the 20th century.
The act signed under President Richard Nixon prevented businesses from dumping in waterways.
Large-scale pollutants in the water became so infrequent that they became news.
In 2004, the Dave Matthews Band made headlines after its tour bus dumped 800 pounds of poop on people on a tour boat under the Kinzie Street Bridge. The band agreed to pay $200,000 to settle a lawsuit in response to the incident.
Illinois Attorney General Kwame Raoul announced in May that his office had reached a $4.8 million settlement with Trump International Hotel & Tower over violations of Prairie State water protection laws. The settlement was reached in response to a lawsuit over tower operators ignoring regulations around minimizing the impact of building cooling systems on aquatic life. The tower sits on the river and draws in 20 million gallons of water daily for its cooling systems, according to the attorney general’s office.
Today, instead, the river has become something of a playground. Tour boats and luxury yachts are constantly cruising beneath the city’s bridges. Groups of neon green kayaks hang near the riverbanks. The walking path along the river is host to bars and eateries. Flowers bloom in riverbank gardens near where fishers angle to hook one of the over 70 species of fish in the water, up from less than 10 before the passage of the Clean Water Act.
On St. Patrick’s Day, the Chicago Plumbers Union dyes the river green. The Illinois Environmental Protection Agency has analyzed the dye and concluded it is safe, according to the Sierra Club.
The river will still become polluted after heavy rainfalls due to runoff from the streets and flushing of city sewage systems. Race organizers said they are prepared to call off the race if water analyses find high concentrations of pollutants.
Chicago-area Olympic swimmer ‘stoked’
Smoliga, a native of the Chicago area, told USA TODAY that she was unfazed about water quality concerns.
‘I’m super stoked about it because I’ve swum in the lake my whole life,’ said Smoliga, who grew up going to Gilson Beach north of Chicago. ‘I see any body of water and I want to swim in it.’
Smoliga won a gold medal in 2016 and a bronze medal in 2020. The 30-year-old also holds the record for most gold medals won in a single FINA World Swimming Championships after winning eight golds at the 2018 World Championships. She said she is training for the 2028 Olympics in Los Angeles.
But the Olympian admitted she was ‘a bit nervous’ about the upcoming swim. She specializes in 50- to 100-meter races and will be swimming a mile. The river swim will also be her second open water race.
‘It’s a totally different beast for me,’ Smoliga said. She added that whatever fears of boredom she expects with long open water swims, she doesn’t expect in the Chicago race. ‘It’s going to be crazy on the river, so many people, the views of downtown, I’ll definitely be mentally entertained.’
How swimming helps ALS
As fun as organizers say it will be to watch Olympic swimmers race in the shadows of Chicago’s iconic architecture, medical researchers say the charity swim also proves vital to developing treatments.
Money raised by the swims goes to fund 46 medical research labs, according to Hande Özdinler, A Long Swim’s director of scientific research and the head of a Northwestern University lab focused on upper motor neurons.
Özdinler, an associate professor of neurology at the Chicago-area university, said she focuses on finding experimental labs developing treatments that are too early in the research process for government funding.
‘ALS is a very complex disease, and you can’t solve complex problems with very linear solutions,’ Özdinler told USA TODAY. ‘We need to bring different expertise together, and that’s what I’m doing, using this money to expedite collaborative efforts.’
Among the most notable of the partnerships where she’s directed support is the development of a new drug NU-9 developed at Northwestern by Richard Silverman that has been found to improve neuron health and is believed it could help treat neurodegenerative diseases, including ALS and Alzheimer’s.
The National Institute on Aging awarded $7.3 million to the lab behind the drug for further research.
A Long Swim’s efforts have been crucial to the development of the new drug and other treatments, said Özdinler, adding she hopes the Chicago River Swim will turn into a major marquee event like the swim in Amsterdam.
‘I hope that this will be the beginning of great things to come and generate momentum,’ Özdinler said. ‘It’s extremely important that we move the field forward, that we see an ALS patient survive.’