Next month, 500 swimmers will take off on a one- or two-mile swim in open water for the Chicago River Swim.

It is a test of endurance and strength, and so was the years-in-the-making effort to get the permit. Organizers tried to hold the swim last year, but it didn’t pan out.

Stop by the Chicago River on a summer day, and you’ll find plenty of kayakers, architectural cruise boats, and people snapping photos and making memories. But swimming, let alone organized swimming in the Main Branch of the Chicago River downtown is not a common sight.

But it could become an event like Bike the Drive or the Chicago Marathon.

“You know, there’s only one day a year I can run down Clark Street, and only one day a year that I can ride my bike on Lake Shore Drive,” said Chicago River Swim organizer Doug McConnell.

Saturday, Sept. 21, will be the first time in 95 years that the Chicago River will host an official open swim. After years of false starts, they are making space for 500 experienced open-water swimmers to take the plunge.

“With a field of 50, we had almost three times that many applications,” said McConnell, “so I feel like there’s, you know, a curiosity factor if nothing else.”

There is curiosity for sure, and skepticism for some.

The idea is a splash from the past, but one that hasn’t been possible until recently.

“Frankly, it makes me want to cry,” said Friends of the Chicago River executive director Margaret Frisbie.

In her 25 years with the Friends of the Chicago River, Margaret Frisbie said she has seen a huge improvement in water quality.

“The Chicago and Calumet River system frankly was fenced off. It was polluted,” said Frisbie. “On average, I used to be sewage in the river every three days.”

Organizers say the group Current has real-time sensors monitoring the water now, and they are partnering with University of Illinois Chicago researchers to test the water in for three weeks before the event.”

Organizers will work with the City of Chicago and the U.S. Coast Guard to close a portion of the river to commercial traffic the morning of the event. The course will be monitored by a hundred people on kayaks, paddleboards, and boats.

 “We’ve committed to the swimmers into the city that we’re not going to allow swimmers into water that is not safe,” said McConnell.

Applications are already open, but organizers are only accepting swimmers who can prove they have participated in other open water swim events before.

Money raised will benefit ALS research and kid swim safety programs.

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