And Here I Thought It Took A Million Food-Color Droppers..

to turn it this green.

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Sponsored by the Plumbers Union, each year forty pounds of vegetable dye is poured into a section of the Chicago River to get this lovely shade of electric green for St. Patrick's Day. (They originally started with 100 pounds, but the river stayed green for a week.)

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The dye actually starts out orange, and changes color once the powder hits the water.

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The dye was originally used to detect leaks into the river.

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Kinda makes for a nice backdrop, doncha think?

(source S1 Photography found via)

For more info, check out the Green Chicago River site.

Happy St. Patrick's Day everyone.