The Chicago River is once again a Flubber-coloured shade of green in celebration of St Patrick’s Day.
Every Saturday before the Irish day of revelry on 17 March – except for the last two years of the pandemic – the river is dyed this striking hue in honour of the city’s Irish roots.
But seventy years on from the tradition being started by Chicago’s plumbers, environmental groups are increasingly keen to see the river left alone.
“Dyeing the river perpetuates the notion that it can be treated any way anyone wants, rather than protected as a valuable natural resource,” says Margaret Frisbie, executive director of Friends of the Chicago River, which has long campaigned for an end to the practice.
“Now more than ever our land and waterways need protection and our traditions need to evolve to reflect that.”
So how did this eye-catching celebration become so popular? Is there an environmental price?
Why does Chicago dye the river green?
The pollution that makes the Chicago River green is inextricably linked to it.
When Richard J Daley became Mayor of Chicago in 1955, he was determined to clean up the city’s riverfront area – starting with the sewage-strewn river itself.
To work out where the waste was coming from, he employed local plumbers to pour an orange concoction into people’s water systems. When the solution came in contact with sewage it turned bright green.
Seeing a colleague’s green-soaked overalls one day reportedly gave Stephen Bailey, a representative of the Chicago Journeymen Plumbers Local union, the idea to scale up the discolouration.
He was co-chair of Chicago’s annual parade, which has been an annual event since the 1950s. In 1962, he turned a portion of the river green. 100 pounds of the chemical were poured in, making it neon for the entire week. It took a few years to perfect this ratio so it would last only for one day.
Photos shared on social media today show that the river is still green from Saturday’s decoration.
Is it dangerous for river wildlife?
Original dye was an oil-based fluorescein. This dye was also used to detect leaks. Environmentalists successfully argued that it was toxic and could cause more harm to the river. The dye was switched to a powdered vegetable-based dye in 1966.
“Illinois EPA has never required a National Pollutant Discharge Elimination System (NPDES) permit so there is no way to know what the dye is or whether it is harmless,” says Ms Frisbie.
But the Friends’ main objection is on grounds of disrespect to the river and its inhabitants. They claim that the water has made great strides since the sixties when it was badly polluted. “Imagine fish, beavers or otters swimming through that dyed-green water and you might think a new celebration is the right idea.”
There’s still considerable room for progress, however. In a video shared to Twitter, Chicago historian Shermann Dilla Thomas says, “If you know anything about the Chicago River, you know that river is polluted.”
The conservation police are also monitoring illegal dyeing, which took place in 2020 and 2021 during the parade’s suspension due to Covid crowd control.
Only a portion of the river downtown can be dyed. However, last year the upper part of the river was also dyed emerald. Whoever the culprits are, “their idea of fun is ecologically harmful and against the law,” says Frisbie.
