St Patrick’s Day: Is Chicago’s green river dyeing tradition bad for the environment?

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 exactly did the eye-catching celebration evolve, and - as onlookers wonder year after year - is there an environmental cost?

Dyeing the Chicago River green is inextricably bound up with pollution.

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 into contact with sewage, it turned a 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.

As co-chair of the parade (an annual occurrence in Chicago since the 1950s) he first turned part of the river green in 1962. 100 pounds of the chemical was poured in, leaving it a neon