THE RIVER — The annual dyeing of the Chicago River is officially underway, with green dye turning the murky water a bright green.
It’s the 64rd year the local plumbers union turned the river green— an effect that lasts for several days.
Thousands of people flocked Downtown Saturday morning to check out the process, lining the river from Columbus Drives far to end of the main branch.
The river dyeing kicked off at 9:52 a.m. Saturday, with Journeymen Plumbers Local Union 130 members dumping their proprietary blend of dyes into the river between Columbus Drive and Orleans Street.
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The plumbers local has been behind the tradition since 1962. The effect became a symbol of the city that’s been well documented in tv shows, movies and your social media feeds for the next few days.
The idea was spawned by Stephen Bailey, who was the union’s business manager in the early ’60s and thought the dye — used to trace leaks in buildings — would be a nice way to celebrate St. Patrick’s Day.
Although the exact concoction remains a closely guarded secret, it is vegetable-based. Dyeing the river only requires about 40 pounds of powdered dye, which is spread from motorboats and shot into the river by hoses aboard Architecture Tours boats. Other boats follow behind to stir the pot and spread the dye.
See more photos of the festivities:
A person holds a Malört bottle filled with a green liquid as the Chicago River is dyed on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
Hundreds of people watch the Chicago River dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Colin Boyle/Block Club Chicago
A person dons a “Kiss me!” stamp after the Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
The Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Colin Boyle/Block Club Chicago
Chicago Police officers dump out “BORG” jugs as people party along Wacker Drive as the Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
People watch the Chicago River be dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
People in leprechaun outfits ride along the Chicago River after it is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Colin Boyle/Block Club Chicago
Various discarded cans and drinks litter the base of a statue after the Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
Hundreds of people mill over the Michigan Avenue Bridge as the Chicago River dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Colin Boyle/Block Club Chicago
People party along Wacker Drive as the Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
The Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
Hundreds of people wait for the Chicago River to be dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
A kid wears a leprechaun hat sticker after the Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
Scenes from the dyeing of the Chicago River on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
People move along a bridge as hundreds of people wait for the Chicago River to be dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
A person holds up a shamrock and horseshoe necklace after the Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
People hold “BORG” jugs as the Chicago River is dyed on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
People record on their phones as the Chicago River is dyed on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
Chicago Police block off Michigan Avenue as hundreds of people wait for the Chicago River to be dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Colin Boyle/Block Club Chicago
A person lays in a planter after the Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
The Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Colin Boyle/Block Club Chicago
Revelers party after the Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
The Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
People hold “BORG” jugs as the Chicago River is dyed on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
Scenes from the dyeing of the Chicago River on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
People film as the Chicago River is dyed on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
People party along Wacker Drive after the Chicago River is dyed green for St. Patrick’s Day by the Plumber’s Local 130 in Chicago on March 14, 2026. Credit: Arthur Maiorella for Block Club Chicago
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