TIMELAPSE: Turning the Chicago River Green

Published 03/17 2014 12:45PM

Updated 03/17 2014 12:52PM

CHICAGO, IL -- The waterway was "greened" this weekend for the annual city-wide celebration.

This timelapse video, uploaded to YouTube, shows this year's process, sped up to a matter of seconds from beginning to end.  Take a look!

They've been doing it for decades but you may be interested to know, it's not really dye that develops that signature green hue - it's a chemical reaction with a substance usually used to detect leaks.  Read more about the history here.

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