Uisce Éireann insists clear water is safe — despite HSE advice to the contrary

Public health expert's advice appears to directly contradict Uisce Éireann's claims at the Oireachtas joint committee on housing

Uisce Éireann’s drinking water compliance manager reiterated the company’s advice that clear water is safe to drink. Picture: iStock  

Uisce Éireann has told an Oireachtas committee that clear water is safe to drink, even though the HSE has told the same committee that water colour does not relate to the safety of drinking water.

Addressing the Oireachtas joint committee on housing last week, Pat O’Sullivan, Uisce Éireann’s drinking water compliance manager, repeated the company’s advice that clear water is safe to drink.

“This primarily would relate to the metals manganese and iron, which can cause discolouration. They are essentially self-limiting, because at the levels that they cause discolouration, there isn’t a public health impact,” he said.

“Someone that has discoloured water, it’s self-limiting, they’re not going to drink it. The levels where it’s clear, it is safe to drink and we’ve proved that comprehensively.

“So, for example, in relation to the advice we gave in Cork over the last few years advising residents not to consume the water if it was discoloured and allow it to run safe to drink, we have comprehensive data sets to show that that was the case.

“We provided all of that with the HSE and they were satisfied there was no further escalation warranted because the correct advice was being given to consumers individually.” 

Public health expert's advice

However, Dr Anne Sheahan, the HSE’s regional director of public health, appeared to contradict that claim.

“The HSE has never advised Uisce Éireann that water that is clear is safe to drink, we always look at the numerics, so ... if it's over 50 [microgrammes of manganese], they shouldn’t have ongoing exposure to drinking that water,” Dr Sheahan said.

The EU Drinking Water (2023) Regulations allow a maximum of 50 microgrammes per litre (µg/L) of drinking water.

Manganese is a naturally occurring mineral which can, at high levels, be extremely harmful, potentially affecting child brain development. In adults, it can cause symptoms similar to Parkinson’s.

The HSE’s regional director of public health Dr Anne Sheahan. File picture

Water quality issues in Cork City

Water quality has been an issue in Cork City since summer 2022, when the then Irish Water opened its €40m Lee Rd water treatment plant.

Documents released last year under Freedom of Information (FOI) to Thomas Gould, Sinn Féin TD for Cork North Central, showed the HSE express serious concerns about manganese levels in Cork drinking water.

A February 14, 2025 letter from the HSE to Brian McCarthy, Uisce Éireann’s regional operations manager, said that in a meeting the previous day, the water utility had clarified that it had not relayed to the public the HSE’s health advice on manganese.

“The HSE emphasises that consumers on affected parts of the supply — when manganese levels exceeding the regulatory limit have been reported by UÉ [Uisce Éireann] to the HSE — need to be given this advice by UÉ."

High Court action

On Wednesday and Thursday, the High Court is to hear a legal challenge by Friends of the Irish Environment against the Environmental Protection Agency (EPA) over drinking water contamination in Cork.