An annual tradition took place Saturday on the Chicago River, as the Chicago Plumbers’ Union dyed the river green in honor of St. Patrick’s Day.
The river dyeing began at 10 a.m., and a brief recap video can be seen in the player above.
Frigid temperatures greeted partygoers on Saturday morning, with wind chills hovering around zero degrees when the boats hit the water. Things won’t warm up much during the day, with highs rising into the low-20s and wind chills remaining in the teens.
For those braving the cold temperatures to get to downtown, the dyed river can be seen from Upper Wacker Drive, as the Chicago Riverwalk will be closed throughout the day Saturday.
According to legend, the idea of dyeing the river was the product of Mayor Richard J. Daley and Chicago Journeyman Plumbers Local 130 business manager Stephen Bailey.
According to the union, Bailey noticed that a plumber’s overalls had been dyed bright green by a chemical that plumbers used to detect leaks along the Chicago River.
That chemical was used for several years to dye the river, but after consultation with environmentalists, a vegetable-based powder is now used, and the recipe is a closely-guarded secret.
The powder is actually orange until it hits the river, then it transforms into the magical green coloring that has enchanted Chicagoans for a half-century.
The river dyeing is one of several events taking place in the city on Saturday, with the St. Patrick’s Day parade stepping off at Balbo and Columbus Drive. The parade will then proceed north toward Monroe Street, according to city officials.