According to the story, the dye used to detect leaks in the sewer system along the Chicago River turned the water green, and the idea was born to dye the river green in honor of St. Patrick’s Day.

According to the story, the dye used to detect leaks in the sewer system along the Chicago River turned the water green, and the idea was born to dye the river green in honor of St. Patrick’s Day.

Here, the river broadens and rushes past us, and the clear water at the source has now turned to dark green. Chemicals suspended inside the water create huge amounts of toxic foam. There's ...