Chicago River runs green for St. Patrick's Day

Posted at 4:03 PM, Mar 17, 2018
and last updated 2018-03-17 16:03:36-04

CHICAGO (WLS/CNN) - Chicago always celebrates St. Patrick's Day in a big way and this year is no exception.

The festivities include dyeing the Chicago River green.

Chicago Plumbers Union Local 130 is in charge of the work. They've been doing it for 55 years and use a proprietary dye to create the spectacle.

It's basically food coloring, The plumbers developed it years ago to help trace leaks in buildings.

This year, the Chicago River turned green from Columbus West to State Street.

The dye usually stays in the water for one or two days.

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