Why does Chicago dye the river green, how to watch
Chicago River Dyeing 2025: Everything you need to know
Here's everything you need to know about the 2025 Chicago River Dyeing and other events happening this St. Patrick's weekend.
CHICAGO - If you've ever wondered why Chicago dyes the river green, it's a tradition as iconic as the city itself. The practice honors Chicago's strong Irish heritage and draws crowds from all over to witness the emerald transformation.
The backstory:
It all started with a grand idea from Mayor Richard J. Daley, who wanted to turn Lake Michigan green for St. Patrick's Day. When he realized how ambitious of a task that would be, he settled for the more manageable Chicago River, using the same green dye plumbers used to find sewage leaks.
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What's in the dye:
Since 1962, the Chicago Journeymen Plumbers Union has been the mastermind behind the emerald transformation we know today. Using 40 pounds of orange-red vegetable-based powder, boats dump the mixture a quarter mile down the river. The plumbers union says the powder is non-toxic, but the formula remains a secret.
Does dyeing the river green impact the fish?
The Chicago River has been dyed green every year since 1962.
How long does the dye last:
In previous years, the dye would stay in the river for up to a week. As of recent, the new formula lasts just a few hours.
Where to watch:
If you’re traveling to Chicago for the annual river dyeing, the most popular places to watch are from the bridges along Upper Wacker or between State and Columbus Drive. The riverwalk will be closed to the public.
If you choose to watch from home, we’ll be streaming live on the FOX Local app from start to finish.