What U.S. city dyes its river bright green each year for St. Patrick’s Day? Correct
To celebrate St. Patrick’s Day, the city of Chicago famously transforms its namesake river into a vibrant, glowing emerald waterway. This annual tradition is spearheaded by the Chicago Journeymen Plumbers Local Union 130, who utilize motorboats to distribute about 40 to 60 pounds of a specialized, vegetable-based powder. Interestingly, the dye itself is actually orange in its dry form, but it reacts instantly upon contact with the water to create the signature neon green hue that has become a global icon of the holiday.
Source:
https://www.youtube.com/watch?v=2g_cIT7nesY
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