The country’s newest official bathing area, Dún Laoghaire Baths, has failed a pollution test and will be out of bounds for swimmers this summer.
The waters, which were only formally designated a bathing area last year after a new jetty and access steps were developed, were found to be polluted from sewage overflows and dog faeces.
It is the only site of 153 popular swimming beaches, lakes and urban coves monitored by the Environmental Protection Agency (EPA) to fail to meet the minimum standards in tests carried out over the official bathing season.
However, almost half the sites were under bathing restrictions or precautionary warnings at some point during the season last year because of pollution concerns.
The number of warnings to swimmers to stay out of the water almost doubled last year, the EPA report shows.
Notices were issued 205 times in 2025, compared to 113 times in 2024.
Many notices were precautionary and prompted by heavy rain that left local authorities fearful that overflowing drains and sewers and run-off from farmland could flood the waters with dirt and disease.
There were 79 confirmed pollution incidents – up from 34 in 2024. The main problem was the presence of E.coli and intestinal enterococci, which can cause severe illness.
The redeveloped Dún Laoghaire Baths. Photograph: Ste Murray
Even where the notices were precautionary, it warned against swimming for 48 hours. Where incidents were confirmed, the prohibition was often longer.
The Sustainable Water Network (Swan), which represents environmental and community organisations concerned with water quality, said such notices “should not become accepted as normal”.
“The solution is to address the root causes of pollution in the first place,” said policy officer Puneeta Sreenivas.
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“This requires stronger Government action such as accelerating upgrades to wastewater treatment, stronger measures to reduce agricultural pollution at source and preventing pollution from septic tanks and private treatment systems entering streams that feed bathing waters.”
Swan also pointed out that 39 per cent of the 120 sites deemed “excellent” were under a warning or restriction at some stage during the season, and said the season was too short.
“Monitoring of bathing waters should also be done outside of the bathing season to protect the growing number of year-round swimmers and recreational water users,” Sreenivas said.
Regulations only require official bathing sites to be tested from June 1st to September 15th.
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Uisce Éireann said it was working to improve wastewater treatment and it noted the EPA report showed improvements in the ranking at several bathing sites where wastewater investments had recently been completed.
It said an “unexpected intense rainfall event” had caused some of the problems at Dún Laoghaire Baths.
The EPA said Dún Laoghaire-Rathdown County Council was working on a management plan to safeguard the bathing waters at the baths.