Why Does Chicago Dye Its River Green Every St. Patrick’s Day?

To celebrate St. Patrick’s Day every year, the city of Chicago turns the Chicago River into a brilliant shade of green. In 1962, Chicago’s plumbers, led by Stephen Bailey, first used vegetable-based dye to color the Chicago River for the holiday as a way to honor the Irish heritage of their fellow residents. 

This quirky tradition has continued for decades and has become an internationally recognized event, drawing thousands of spectators to the riverwalk area of Chicago’s downtown.

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Why does Chicago dye its river green every St. Patrick’s Day?

Every year, on March 17th, the city of Chicago celebrates St. Patrick’s Day with a very special tradition: the dyeing of the Chicago River green.

 The event began in 1962 when a small group of local plumbers wanted to visually celebrate the Irish heritage of Chicago by creating this unique and bold method to color the river. 

They use an environmentally safe dye that is released into the river early in the morning, transforming it from its natural color to an incredible emerald green for several hours.

Since then, this event has become one of the most widely recognized celebrations in the world and attracts thousands of visitors from around the world who come together to celebrate the Irish heritage of Chicago and the arrival of spring. 

The Tradition Behind the Green River

The process of dyeing the river begins in the early morning hours leading up to the start of the parade. The crews responsible for dyeing the river use safe (for humans and the environment) powdered dye and drop it into the river.

Because the river is a slow-moving body of water, it allows the dye to spread evenly and remain vibrant in color for several hours.

Over the years, this method has been improved in order to lessen the impact on the environment while still maintaining an eye-catching and photographic appearance.

Why It Continues?

The continued success of this tradition is due to both its novelty and symbolism. It acknowledges the Irish-American heritage of the city while providing an opportunity for people to come together in a shared experience of joy every March. 

The striking appearance of the green water has caught the imagination and generated significant media coverage every year in major media outlets around the world.