Irish Rivers Turning Green — But not for Saint Patrick

Along with an abundance of shamrocks and a plethora of dancing leprechauns, one of the most iconic celebrations of Ireland’s patron saint is the annual tradition of dyeing urban American rivers green around March 17.

Matthew Woodard


Along with an abundance of shamrocks and a plethora of dancing leprechauns, one of the most iconic celebrations of Ireland’s patron saint is the annual tradition of dyeing urban American rivers green around March 17.

The most famous ‘greening of the waters’ occurs in Chicago on the Saturday before Saint Patrick’s Day each year. This event is credited with having started the tradition across many US cities. And while it began with more toxic chemicals, today the dye used to transform the river is an environmentally friendly solution made from vegetables. Nicknamed ‘Leprechaun Dust’, the exact recipe of the dye remains a guarded secret.

However, when Chicago’s river was first dyed green in 1955, it was for a more serious reason than celebrating a public holiday and creating a tourist attraction. The tradition happened by chance in the mid-1950s after the Mayor of Chicago wanted to clean up the waterfront area that was neglected and unused because of the water's pollution levels. Therefore, a bright green dye was added to help trace the source of the leaking pipes and pollution spills.

The river was first turned green deliberately to celebrate St Patrick's Day only in 1962 by Stephen Bailey, who worked as a representative of the Chicago Journeymen Plumbers Union and co-chair of the St Patrick's Day Parade. Now it’s heralded as a much-anticipated celebration of the Irish American connection that draws thousands of people to witness it.

Green river Green river 1

In 2021, none of Northern Ireland’s 496 rivers, lakes and coastal waters achieved a ‘good overall status’ rating for water quality. Last year, Ireland’s Environmental Protection Agency estimated that 40-50% of rivers fail to reach their environmental standards. Many of its carbon-sequestering ancient peat bogs and wetlands are degraded or destroyed completely. A recently published study in Nature revealed that 70 per cent of wetlands worldwide have disappeared in the last 100 years. Across the island of Ireland, that figure rises to 90 per cent.

In Ireland, many rivers are turning green every day – but not to celebrate Saint Patrick. They are choked by algae blooms caused by agricultural nitrate run-off, pumped full of sewage and waste, invasive species block their banks, and they are filled with plastic litter. Unlike the 1950s Mayor of Chicago, we are very clear about where the pollution is coming from.

Our 21 Rivers Trusts, Associations and community volunteers across the island of Ireland continue battling to improve and protect our precious rivers for today and future generations as we try to fulfil our mission statement of wild, healthy rivers enjoyed by all. So, if you really want to honour Ireland on Saint Patrick’s Day this year, spare a thought for the rivers across the island that are turning green for all the wrong reasons.

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