One of the most colorful Chicago traditions is on the horizon: The 2025 Chicago River Dyeing in honor of St. Patrick's Day.
The legendary event, which dates back more than 60 years, takes place for 2025 on Saturday, March 15. according to Choose Chicago, when boats will spread the eco-friendly dye throughout the river until the water is a bright, emerald green.
The dye is often visible several days after the event and through the St. Patrick's Day holiday.
Some events take place even before the big river dyeing. Sunday in the suburbs, the Village of Tinley Park will hold its 25th annual Irish Parade. The parade steps off at 1 p.m., with road closures expected.
As St. Patrick's Day events and the Chicago River Dyeing approach, here's what to know.
What time is the Chicago River dyeing for 2025?
If you're interested in seeing the color change in person, you'll want to head to State and Columbus at 10 a.m. While the lower Riverwalk will be closed, spectators can watch from Upper Wacker Drive or one of the city's many bridges.
Where to watch the Chicago River dyeing
The lower Riverwalk will be closed, so to watch the color changing phenomenon take place, spectators should head to Upper Wacker Drive or one of the city's bridges. NBC Chicago also plans to stream the event live on NBCChicago.com, the NBC 5 Chicago News streaming channel and our YouTube channel.
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Some of the best views for watching the river transform to emerald green are between Columbus Drive and Fairbanks Court.
How did the tradition start?
The story goes, in 1961, a man by the name of Stephen Bailey -- the business manager of the plumbers union -- was approached by "one of his plumbers who was wearing some white coveralls," a post by Local 130 says. It was then the union says, that Bailey noticed the overalls had been stained or dyed with "a perfect shade of green," or "an Irish green to better describe it."
When wondering how the coveralls could have turned such a tint, the tale continues, Bailey and his plumbers discovered that it was from to the dye used to detect leaks in the river.
"That's when Mr. Bailey bellowed," the Union declares, "Call the mayor ... we will dye the Chicago River green!"
And there you have it.
Who dyes the river green and how?
Each year around St. Patricks' Day, members of the Chicago Plumbers union embark on boats that putter across the Chicago River, with a rather curious concoction that sprays dye out of plumping pipes and spout pumps.
But the mysterious mixture doesn't come out green.
"If you were watching this for the first time you would think this is a mistake or a bad joke," the union's post goes on to say. "You see the dye is orange, and its initial color on the surface of the river is orange, and you would think to yourself what 'heathen would do something like this.'"
However, once the dye sets in, the color in a stroke of luck changes to green, and the "true color magically appears," the union says.
According to Local 130, other cities have attempted similar feats, but never found success. It's that, the union says, and the magical color transformation that perhaps plumbers may have had some additional help with.
"We believe that's where the Leprechaun comes in," Local 130 says.
"As the late Stephen Bailey has said, the road from Chicago to Ireland is marked in green," the post regales. "From the Chicago River to the Illinois River, then to the Mississippi, up the Gulf Stream and across the Atlantic you can see the beautiful green enter the Irish Sea, clearly marking the way from Chicago to Ireland."
What's in the dye?
We'll never know.
The plumbers union, Choose Chicago says, "still holds the river-dyeing honors today." But you won't be able to find their recipe anywhere. "Their environmentally friendly dye formula remains a closely kept secret," Choose Chicago says.
Other St. Patrick's Day events in Chicago 2025
Archer Ave. St. Patrick's Day Parade
A celebration of Chicago's working families, the Archer Avenue St. Patrick's Day Parade is also scheduled for Saturday, March 15. Paradegoers will be able to line up along Archer Avenue as the parade travels from Oak Park to Narragansett.
It is slated to start at noon.
Chicago St. Patrick's Day Parade
After the dyeing of the Chicago River, St. Patrick's Day weekend festivities will continue with the 70th annual Chicago St. Patrick’s Day Parade.
As in years' past, the parade will likely kick off at Balbo and Columbus Drive and proceed north to Monroe Street. A start time hasn't been announced. The parade is sponsored by Chicago's Plumbers Local 130 UA, which is responsible for turning the river green.
Northwest Side Irish Parade
Celebrating faith, family, and heritage on the Northwest Side, the community's Irish parade has been taking place for 22 years now.
This year, it's planned to get underway at noon on Sunday, March 16.
An estimated 50,000 people are expected to flock to the area for the community tradition. The parade will step off at Onahan School, 6633 W. Raven.
South Side Irish Parade
The largest community-based St. Patrick's Day Parade outside of Dublin, Ireland, the South Side Irish Parade, also steps off on Sunday, March 16.
Floats, bagpipers, traditional Irish dancers and more will travel down Western Avenue as onlookers take in the sights. The parade kicks off at noon at 103rd and Western Avenue and will end approximately two hours later at 115th and Western.
Saint Patrick's Fest - Irish American Heritage Center
The Irish American Heritage Center is hosting its Saint Patrick's Fest on the afternoon of March 15 - after the day's parades wrap up. You'll be able to take in traditional and contemporary Irish music, see Irish dancers perform and make purchases from vendors selling Irish gifts.
There will even be children's activities.
The event is planned from 1 to 11 p.m. at 4626 N. Knox Ave.
