Cork water: EPA's approval of Uisce Éireann action plan challenged in High Court

Residents are being 'misled' that clear water is safe, and manganese levels are above safety limits, according to the legal challenge

A photo contrasting bottled water and Cork tapwater which has often been discoloured since the inception of the new Lee Road water treatment plant. However, Friends of the Irish Environment say clear tapwater can also contain contaminants. File picture: David Creedon

A legal challenge over drinking water contamination in Cork has been launched against the Environmental Protection Agency. 

High Court proceedings have been entered seeking a judicial review of the EPA's approval of Uisce Éireann’s June 2025 Remedial Action Plan to address persistent contamination of Cork City’s public drinking water with what is claimed to be dangerous levels of manganese.

The applicants, Friends of the Irish Environment (FIE), together with Cork City residents Elaine Eager and Daniel O’Shea, argue that the EPA misdirected itself in law by approving Uisce Éireann’s Remedial Action Plan without determining if manganese levels posed a risk to human health or ensuring that successful remedial measures were carried out “as soon as possible” as required under the EU Drinking Water Directive.

According to the filings, Cork’s water supply flows through a 100-year-old cast iron pipe network. When the new Lee Road treatment plant opened, the slightly different chemical composition of the treated water reacted with sediments contained within the water mains, releasing iron and manganese that had built up over decades, it said. 

Manganese levels 'above safety limits' 

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Repeated breaches of the European regulatory threshold of 50 microgrammes per litre of manganese are shown in documents in the proceedings, a statement from FIE said.

"The pleadings include documentation obtained from Uisce Éireann reporting 61 separate chemical exceedances between August 2024 and July 2025. Manganese, which is particularly harmful to infants and young children, has been linked with neurological developmental damage when consumed at high levels over time," the FIE said.

FIE Director Tony Lowes said that Uisce Éireann has continued to advise residents that the water is safe to drink once it runs clear, "which is simply not true." 

"Clear water can contain manganese levels above the safety limits," Mr Lowes said.

"The EPA failed to consult with the Health Services Executive [HSE] and treated an issue of public health as one solely of discolouration, failing to recognise the contamination risk in clear water and so neglecting its supervisory responsibility. 

Settlement tanks at the Uisce Éireann Water Treatment Plant on the Lee Road, Cork. Friends of the Irish Environment and Cork residents are challenging the approval of Uisce Éireann’s June 2025 Remedial Action Plan. File picture: David Creedon

"Without proper consultation with the HSE and without public transparency the EPA is in breach of both the Aarhus Convention and EU environmental law." 

According to FIE, “This case is about Ireland’s failure to fulfil its legal duties under the European Union (Drinking Water) Regulations 2023 (S.I. 99/2023) to protect public health by ensuring the fundamental right to safe drinking water. 

Residents 'misled' that clear water is safe

"After years of complaints, investigations, and persistent non-compliance, Cork residents are still experiencing regular exceedances of the safe levels of manganese and are being misled by being told their water is safe if runs looks clear. That is not what our expert scientific evidence or EU law says.” 

A previous judgment against Ireland in 2024 was made on the basis of a FIE complaint to the European Commission in 2011 about exceedances in Irish water of the chemical limits for trihalomethanes [THMs].

Ireland’s defence said it was difficult to reach the required standards in some sources because of the country’s geography, with peatlands and higher than average rainfall. 

But the EU Court rejected Ireland’s defence and ruled that THMs in Irish drinking water exceeded EU safety levels. 245,000 consumers are still being provided with water that exceeds the THM limits, FIE said.