Since 1962, plumbers from The Chicago Journeymen Plumbers Local Union 130 have dyed the Chicago River green for St. Patrick's Day. Carhartt, America's premium workwear brand, and Guinness, one of the world's most iconic beers, have come together to celebrate the holiday and pay tribute to the hard-working men and women who host the iconic celebration. In a new video titled, “The River," the companies spotlight the Chicago Plumbers Union as well as the people behind Chicago's iconic St. Patrick's Day parade. The video can be watched on Carhartt's Youtube channel.

An eco-friendly vegetable-based dye has been used to create the iconic green color of the Chicago River on the day of the St. Patrick’s Day parade since 1966. While the contents of the dye remain a closely guarded secret, it has been approved by the city of Chicago, as it has been thoroughly tested and deemed safe for all aquatic wildlife and plants.