Early reports indicated that it could be an organic dye ... negative impact. Runoff from human enterprises has a track record of polluting waters. In Maryland, Gunpowder River in recent years ...

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 ...

and the dye typically lasts a day or two (here's how they dye the river). After the water changes colors, it's off to Grant Park for the Chicago St. Patrick's Day Parade. While it's free to ...

One longstanding ceremony is the dyeing of the Chicago River, when artificial coloring is used to turn the water an emerald green during the week leading up to St. Patrick's Day. The event is a ...