The Chicago River is once again glowing kelly green as the city opens its annual St. Patrick’s Day celebrations. On Saturday, March 15, 2025, thousands gathered along the river and packed bridges, erupting in cheers as members of the Chicago Journeymen Plumbers Union Local 130 sprayed dye from boats, continuing the 63-year tradition.
This year’s dyeing event kicked off the festivities leading up to St. Patrick’s Day, which falls on Monday, March 17, 2025. St. Patrick is revered as the patron saint of Ireland, known for having brought Christianity to the country back in the fifth century. The delight of spectators watching the vibrant transformation from the usual blue to bright green adds to the rich cultural heritage of the day.
The event has become one of Chicago's most beloved traditions, with the dye process using non-toxic, vegetable-based dye—a mix of roughly 40 pounds of orange-red powder—sprayed by union members. This mixture changes color as it settles, resulting in the bright green shade the city is renowned for on St. Patrick's Day. The eco-friendly nature of the dye was emphasized, ensuring safety for local wildlife and the environment.
While the river typically stays bright green for about five hours following the dyeing, some traces of color can remain for days, much to the delight of hopeful holiday revelers. Reports from Choose Chicago noted early Monday morning, March 17, at 8:30 AM, the river's shamrock color was still prominently visible.
The spectacle of the dyeing escalates anticipation for the annual downtown St. Patrick's Day parade, which is also immensely popular. Much like the river dyeing, this parade is filled with joyous celebrations of Irish culture, music, and dance. A second parade was scheduled for the South Side of Chicago on Sunday, March 16, ensuring the vibrant celebrations continue across the city.
The history of dyeing the Chicago River dates back to 1962. This tradition began when Chicago's then Mayor Richard J. Daley observed the potential for using dye to trace polluters. The original aim was to turn Lake Michigan green; luckily, the endeavor was rethought, leading to the now-iconic dyeing of the Chicago River instead. This clever plan has since blossomed, turning what began as leak detection measure to one of the city's most cherished public events.
Past years have shown impressively how long the green remains, with some participants recalling the river maintaining its emerald hue well beyond the celebrations. Last year, the Chicago River stayed green for several days, drawing curious onlookers eager to extend the festivities.
Photos and videos surfacing on social media allow individuals who cannot attend to catch glimpses of the magic happening on the river. Many took to posting their excitement online, sharing these vibrant views and relishing the festive atmosphere of the city.
Experts caution, though, the intensive dyeing process requires precise coordination and execution, as the timing and method need to be exact for the desired brightness of the color.
The Chicago River dyeing event has become more than just about dye—it's about community, history, and celebrating culture. Enthusiasts express gratitude for the tradition and appreciate how it brings together residents and visitors alike.
Looking forward, this beloved annual event continues to evolve yet remains deeply rooted in Chicago's rich traditions. Cheers and laughter will undoubtedly fill the air again as people anticipate the next installment of the lively and colorful theme surrounding St. Patrick’s Day, right alongside the smartly doused river.
Until next year, the memories of this year's celebrations are sure to resonate, leading many locals to wonder what creative additions the city might introduce to future St. Patrick's Day festivities.
