If you visit Chicago during St. Patrick’s Day, you will undoubtedly witness one of the strangest traditions in the country: the river dyeing. For five decades, Chicago has put on a shade of bright emerald green that matches that of the people celebrating, by dumping 40 pounds of environmentally friendly dye right into the Chicago River.
In 1961, the business manager for the Chicago Journeymen Plumbers Local Union noticed that a plumber’s white overalls had bright green stains all over it, seemingly matching the emerald green often associated with Ireland, due to the dye used by the Plumbers to find leaks in pipes. Then, in 1962, the Plumbers Local Union decided to use 100 pounds of that dye in the river to turn it green for St. Patrick’s Day - and it stayed that way for a week!
Over the years, the Plumbers Local Union have figured out the amount of dye (and what kind) to use to get that classic emerald green, and thankfully it only lasts for a few hours so Chicagoans aren’t reminded of their post-St. Patrick’s Day hangovers for the whole week afterwards.
Since the whole river takes on this iconic color, there are a lot of great spots to view the dyeing on St. Patrick’s Day. We recommend trying to find room on any of the bridges crossing the Chicago River, but you might have to get there early to snag the prime spot. But, of course, any spot along the river edge will give you a wonderful view of this one-of-a-kind visual treat.