Wastewater discharges continue to be a significant pressure on water quality in many of Ireland’s rivers, estuaries, lakes and coastal waters, Environmental Protection Agency (EPA) director Dr Tom Ryan has said.

Speaking following the publication of the EPA’s Urban Wastewater Treatment in 2023 report, he said that without an ambitious and sustained investment programme to build out wastewater treatment infrastructure “it could take over two decades to achieve the required standards to protect the environment."

The EPA has said that two decades is too long to wait to fix Ireland’s deficient wastewater treatment plants.

The report found that while there was a 45% reduction in the number of towns and villages discharging raw sewage since the start of 2023, wastewater treatment at many areas is not good enough to prevent wastewater discharges. Sixteen towns and villages are currently discharging raw sewage to water bodies every day.

Wastewater treatment at many areas is not good enough to prevent wastewater discharges

“All deficient wastewater works must be brought up to the standards required to protect the environment but, based on Uisce Éireann estimates, this could take over two decades and will require substantial investment,” the EPA said.

“As it is not possible to fix all the problems in the short term, improvements must be prioritised where they are needed most.

"The EPA has identified 73 priority areas where improvements in wastewater treatment are most urgently needed to protect our environment. Uisce Éireann has not yet started upgrade works at half of these,” it said.

The EPA has said that Uisce Éireann must accelerate the pace of its upgrades and that it must comply with EU treatment standards and eliminate raw sewage discharges.

Sixteen towns and villages discharging raw sewage in mid-2024. \ EPA

It said that the sewer system must be improved and that collecting systems at six priority areas must be upgraded. It called on Uisce Éireann to prevent pollution of inland and coastal waters and to protect vulnerable habitats.

Slow progress

Dr Ryan said that investment has resulted in stopping raw sewage discharges during the past year from 13 towns and villages that were priority areas highlighted by the EPA.

“This demonstrates that such investment protects our environment and benefits our local communities. The much-needed upgrade of Ireland’s largest treatment plant at Ringsend in Dublin, treating over 40 per cent of all national wastewaters, is now well advanced, and this is to be welcomed.

“At an operational level, Uisce Éireann’s slow progress in designing and delivering the solutions needed at the waters most affected by wastewater discharges are prolonging impacts on water quality. Uisce Éireann must prioritise the prompt delivery of these essential works,” he said.

Licences

The Urban Waste Water Treatment Directive sets general European wide treatment standards for large towns and cities. Ten areas, including Dublin, failed these basic standards in 2023.

Wastewater discharge licences issued by the EPA to Uisce Éireann may specify more stringent standards than those in the directive when such standards are necessary to prevent and reduce pollution of waters. Over half of licensed treatment plants discharge wastewater that does not always meet these licence standards.

Noel Byrne, EPA programme manager, said that wastewater discharge licences issued by the EPA set out the treatment standards needed to prevent pollution by wastewater discharges and protect rivers and coastal waters.

“It is unacceptable that over half of licensed treatment plants do not always meet these standards, with issues ranging from short term breaches of treatment standards up to continuous discharges of raw sewage.

"The short-term breaches should be resolved through effective management and maintenance of equipment. Uisce Éireann must address infrastructural deficits at the priority areas highlighted by the EPA during its 2025 to 2029 investment cycle.

"This will help deliver significant environmental benefits and protect water quality.”