Every year since 1962, The Chicago Journeymen Plumbers Local Union 130 UA have dyed the river in a vibrant green for St. Patrick's Day celebration.
Typically thousands of people watch the river being dyed as part of a much larger parade in the Windy City - everyone is Irish on St. Patrick's Day !
Learn more about this joyful celebration in the articles below:
How Do They Dye the Chicago River Green for St. Patrick's Day?, Mental Floss
Chicago River goes green for St. Patrick's Day!, ABC
Time Lapse Shows Chicago River Dyed Green in 30 Seconds, NBC Chicago