Video: Watch a timelapse of the Chicago River being dyed green for St Patrick's Day

From: msn video

Following in the footsteps of the White House fountain, the Chicago River has been dyed green to mark St Patrick's Day. 

Getting the famous river to glow is no easy task, however. It takes three boats several hours to spread an orange powdered dye across the surface. Once the chemical hits the water it changes colour to a fluorescent green as you can see below:

Many locals may grumble that the river is a shade of murky green all year round due to pollution but it's interesting to note that this unusual Paddy's Day tradition actually stems from the city council's efforts to clean up the waterway.

Members of the local plumbers union used to dye the river green for more than 50 years to detect illegal sewage dumping. They would check the buildings along the river for sewage using the formula, which would turn green if toxic sludge was present. 

Now they do it just for fun – it looks great!

Categories: Ireland, US, St Patrick's Day