How the Chicago River is dyed green for St. Patty's

March 15, 2019 - 11:30 am

CHICAGO (WBBM Newsradio) — Organizers of Chicago’s downtown St. Patrick’s Day Parade offered a sneak peek of Saturday’s event, including the preparations necessary to dye the Chicago River green.

Jim Majerowicz of Plumbers Local 130 showed reporters how an orange-colored dye powder is mixed with water and sprayed to create the emerald hue. 

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He declined, however, to say what’s in that dye.

“It’s basically an FDA dye. We never say what’s in it,” he said. “Otherwise, it would be all over the place.”

Dyeing the river green has been a Chicago tradition since 1962.