Quality of drinking water for one million people needs improvement – EPA

Irish Water’s failure to improve plants risks ‘health of a large portion of the population’

Irish Water’s failure to improve treatment plants has left many water supplies vulnerable and poses a risk to the “health of a large portion of the population”, the Environmental Protection Agency (EPA) has said.

The agency’s report on drinking water supplies in 2020 says overall quality was high, with 99.7 per cent of samples compliant with bacterial and chemical limits. However, it says 46 water supplies serving more than one million people require significant improvement and that there had been delays in completing works on more than half of these.

The EPA said more than 15,500 people were on boil-water notices for longer than one month last year and that it would “take decades for Irish Water to remove all lead connections at their current rate of replacement”.

The report noted that a high level of water quality was being achieved in most cases which was “positive for consumers” but that improvements are needed in drinking water infrastructure to protect public health.


"It is good news that our water is safe to drink today, but we cannot say with confidence it is resilient into the future," said EPA director Dr Tom Ryan.

“The EPA remains concerned about the vulnerability of many drinking water supplies nationally. Irish Water needs to fix the remaining supplies on the EPA’s remedial action list without further delay.”

The EPA has identified a priority list of "at-risk" drinking water supplies – known as the remedial action list – where it says significant issues need to be addressed by Irish Water. It includes supplies serving more than 90,000 people in Cork city; 17,000 people in Longford central, and 1,300 people in Corofin, Co Clare.

A supply may be placed on the list if it cannot consistently ensure that the drinking water is free from bacteria, protozoan organisms or chemical substances, and that the treatment plant is operated effectively and correctly.

The number of supplies on the list has fallen to 46 from 77 in 2017. Through EPA-targeted enforcement, Leixlip public water supply has been removed from the list, with works there resulting in a more secure supply for 590,000 people. However, improvement works at almost half of the at-risk supplies will now take longer to complete than had been anticipated at the end of 2019.

Among these, the EPA highlighted the Clonmel-Poulavanogue supply in Co Tipperary. Irish Water had said that this was due to be completed by December 2020, but it now has a completion date of December 2026.

The EPA said drinking water improvements last year included the completion of treatment plant upgrades at Staleen, Co Meath (serving more than 70,000 people), Lough Talt, Co Sligo (serving some 12,500); and Ballyhooly, Co Cork (serving 1,200 people).

Dr Ryan said recent incidents at Gorey and Ballymore Eustace water treatment plants highlighted "the absolute necessity for Irish Water to ensure our public water supplies are properly and effectively operated, and managed, to protect public health".

The EPA also found deficiencies in the national disinfection programme, and “a continued lack of focus” by Irish Water and the Department of Housing, Local Government and Heritage on plans to remove lead from supply connections and assessments of the extent of lead pipework in public buildings.

EPA programme manager Noel Byrne confirmed that 145,000 households still have lead connections from water mains "which highlights the vulnerabilities that exist in drinking water supplies". He said Irish Water must expedite lead connection replacements and progress improvements to disinfection systems to ensure the quality of drinking water is adequately safeguarded.

While detections of cryptosporidium and giardia protozoans, which can cause severe illness, have reduced by one third since 2019, the EPA is concerned these organisms are still being detected “due to a failure to properly manage treatment processes”.

It is critical that Irish Water put appropriate control measures in place to ensure correct operation of treatment processes, it said, adding that this was achieved at the Leixlip plant, which was removed from the list in July following filter upgrades and the installation of UV disinfection.www.epa.ie

Irish Water response

The 2020 report indicates “a world class level of compliance with the drinking water regulations”, Irish Water said.

“Given the size and scale of investment needed to upgrade water treatment plants and the wider water network, Irish Water is very pleased to achieve such a high compliance rate for the Irish public,” said Katherine Walshe, its head of environmental regulation.

During 2020, the utility made major investments in new and upgraded plants as well as delivering improvement programmes at its plants to enhance the quality and consistency of supply, she said.

Key programmes such as the national disinfection programme, and removal of the risk of trihalomethanes (THMs) and cryptosporidium were helping to ensure clean, safe drinking water throughout the country, she said. In 2020, Irish Water invested €450 million in building or upgrading 58 water treatment plants which collectively addressed long running water quality risks for THMs and cryptosporidium.

Further progress has been made in 2021 with significant upgrades completed at Leixlip Water Treatment Plant, at Stillorgan Reservoir, and at Vartry Water Treatment plant. These works would ensure more than 1 million customers will receive a safe and secure supply into the future, Ms Walshe said.

“We are advancing drinking water safety plans for all of our larger supplies, with a key emphasis on minimising risks from source to tap. We have engaged extensively and comprehensively with the EPA on this and will prioritise funding towards those schemes at highest risk,” she said.

She acknowledged much more remains to be done to secure water supplies into the future, while Irish Water would work with local authorities and other delivery partners to further enhance its ability to manage public water supplies to the required standards as set out in EU drinking water directives.

“Irish Water have also rolled out critical training to all local authorities to ensure alarms and controls are in place and are operationally effective to ensure public health is protected now and into the future,” she said.

It was also making strong progress in reducing the number of long-term boil water notices in place around the country. Since its establishment, 263 boil water notices had been lifted, benefiting some 1.8 million people.

In all instances where notices are required immediate action is undertaken to address the underlying causes of the issue to enable the lifting of the notice as soon as it safe to do so, she confirmed. "In some cases, this may take time as capital investment may be required to address a treatment deficiency. Irish Water has addressed all long-term boil water notices that were in place before it was established, and the average duration of all subsequent notices is decreasing," she noted – the EPA report is available at: www.epa.ie

Kevin O'Sullivan

Kevin O'Sullivan

Kevin O'Sullivan is Environment and Science Editor and former editor of The Irish Times