Priority urban areas where treatment needs to improve

Aerial photo of Tubbercurry WWTP

There are deficiencies in many public sewers and waste water treatment plants, due to a legacy of under-investment.

Consequently, waste water from some areas discharges into the environment without adequate treatment. It will not be possible to fix all these problems in the short term, and therefore Uisce Éireann must ensure that the resources that are available are directed where they are most needed. We have identified the priority urban areas where treatment must improve in order to resolve national environmental priorities.

You can see the full list of priority urban areas and the environmental issue at each area at this link. This also shows when and how Uisce Éireann plans to resolve the priority issue at each area. There is further information on the priority areas in the EPA’s latest Urban Waste Water Treatment Report.

The number of priority areas where treatment needs to improve has decreased from 148 in 2017 to 80 at the end of 2023.

Priority Areas

Compliance with the Urban Waste Water Treatment Directive

In 2022, treatment at 15 of Ireland’s 173 large urban areas failed to meet European Union standards set to protect the environment.  The graph shows the number of areas that failed to meet the standards over the period 2017 to 2022.

The 15 areas that failed the standards in 2022 generated over half (55%) of the total waste water collected in all 173 large urban areas. The failure of Ringsend treatment plant to meet the required standards is of particular concern because it treats waste water from a population equivalent of over 2 million


Compliance with Urban waste water treatment directive

Raw sewage  

At the end of 2023, untreated waste water (raw sewage) from the equivalent of approximately 47,000 people in 19 towns and villages still flowed into the environment every day. 

Based on Uisce Éireann’s latest plans, nine of these areas will be connected to treatment plants by the end of 2025 and the remaining areas are expected to receive treatment between 2027 and 2030.

The chart shows the number of areas that will still have no waste water treatment plant at the end of each year, based on the latest Uisce Éireann plans.

Thirty-one areas that were discharging raw sewage have been connected to treatment plants since 2014.

Raw Sewage

Significant pressures on water quality

Coastal water

If waste water is not properly treated before it is released into the environment it can adversely impact the quality of rivers, lakes and coastal waters. The EPA is prioritising 36 areas where waste water is a significant pressure on inland and coastal waters at risk of pollution. 

Improving treatment at these areas will help protect and improve the quality of the local environment, which will in turn support local communities, healthy ecosystems and a diverse range of plants and animals. 





Urban waste water collecting systems

Storm water overflow pipe into stream

Ireland’s waste water collecting systems include thousands of kilometres of underground sewers and pumping stations that carry sewage from our homes and communities to treatment plants.  In 2019 the Court of Justice of the European Union ruled that collecting systems serving some areas were inadequate.  When a collecting system is inadequate it cannot retain all the waste water collected in the sewer and convey it for treatment.

Uisce Éireann must complete improvements on 6 priority collecting systems to bring the systems up to standard and resolve the issues highlighted by the Court.



Bathing Waters

bathing water beach kerry

Most of Ireland’s bathing waters meet or exceed the minimum required quality standards. However, waste water discharges contributed to a poor bathing water classification at three designated bathing waters in 2022.



Pearl Mussel

Pearl Mussel

The EPA is prioritising 12 towns and villages where waste water treatment must improve to protect freshwater pearl mussels that live in the rivers downstream of waste water discharges. The fresh water pearl mussel is a globally endangered mollusc that requires clean, fast flowing, well oxygenated rivers and a clean riverbed. 

The mussels are declining both nationally and internationally due to deteriorating river quality. Pollution, for example from inadequately treated waste water, can be detrimental to the survival of new generations of mussels.