In 1962, Chicago city workers dumped 100 pounds of dye into the river flowing through downtown Chicago. It left the river emerald green for an entire week and kick-started an annual tradition.

However, the emerald river is raising questions about the tradition's environmental impact. The practice of dyeing the ...

Some of the best views for watching the river transform to emerald green are between Columbus Drive and Fairbanks Court. What is this mysterious dye made of? Sadly, we don't know. The ...