In Chicago, Illinois, every year since 1962, on the Saturday before St Patrick’s Day, it’s a tradition to dye the Chicago River green in celebration of St Patrick’s Day. 

Originally, it started out as a 100-pound, oil-based pollution-tracing tactic. It was proposed by Plumbers Local Union. Nowadays, the “secret formula” includes roughly 40 pounds of eco-friendly, vegetable-based power, which turns the water the well-known emerald green color. Which usually stays for a few hours.  Two boats are used during the process. One drops the orange-red power (which turns green as it hits the water), and the other mixes it. 

The dyeing of the Chicago River has become one of the most iconic St Patrick’s Day images within the United States. Thousands of people line the river and bridges each year to watch as the water turns from its normal color to a vibrant emerald color. It’s part of a larger celebration that includes one, but sometimes two parades, Irish music, food, and festivities that honor Irish culture and heritage.  It also inspired a fun moment back in 2009, when the White House fountains were dyed green to celebrate the holiday. 

What started as a quirky idea from plumbers over 60 years ago has become one of Chicago’s most distinctive St. Patrick’s Day celebrations. Every March, a combination of history, community spirit, and a splash of bright green turns the Chicago River into a symbol of celebration. A beautiful tribute to Irish culture that captures the imagination of both locals and visitors alike.