When Do They Dye The Chicago River 2025. How do they turn the chicago river green? You can watch the river going green between columbus and wacker drives.

These days, they use just 40 pounds of dye and the green magic lasts for several hours. Friends of the chicago river is proud of the part we played in improving the river’s health and transforming it from a back alleyway to a true economic engine that is healthy, accessible, and fun.