WATCH: Time-lapse video of green Chicago River

Julianne Cassidy

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WATCH: Time-lapse video of green Chicago River

By Julianne Cassidy. CREATED Mar 17, 2014

This time-lapse video shows the mysterious "leprechaun dust" transformation of the Chicago River for St. Paddy's Day. 

As previously reported, Chicago celebrated its 58th annual St. Patrick's Day parade on March 15 with an estimated 500,000 spectators lining Columbus Drive. 

The kelly green hue that you'll see above is made from a secret compound the Chicago Plumbers Union Local 130 proudly refers to as "leprechaun dust."

The river remains dyed for an estimated six to 12 hours.