It's not all bad news as we also have some of Ireland's best beaches.
Five of Ireland's seven dirtiest bathing spots are in Dublin, according to the latest report on water quality across the country.
They failed to meet the minimum standards required by the Environmental Protection Agency and the EU.
The five Dublin bathing waters rated "poor" in 2017 were Sandymount (sufficient in 2016) and Merrion Strands, Loughshinny, Portrane and Rush South (sufficient in 2016). The other two poor ratings were in Co Galway.
Several Dublin bathing areas also deteriorated over the past year, including Claremont (sufficient in 2017, good in 2016), Donabate (sufficient in 2017, good in 2016) and Skerries (sufficient in 2017, good in 2016).
But we also have some of Ireland's best bathing spots, with the Velvet Strand in Portmarnock, Burrow Beach in Sutton and Seapoint all ranking excellent for water quality.
The report gave particular mention to Dublin Bay, saying: "All of the Dublin Bay beaches are monitored more intensively than required under the Bathing Water Regulations.
" Dublin City Council and Dun Loaghaire-Rathdown Council sample at least weekly during the bathing season with Fingal County Council sampling its beaches typically fortnightly.
"This ensures a high degree of public health protection but also increases the likelihood of finding periodic poorer quality.
"20 Investigations of the Trimleston and Elm Park streams by Dublin City and Dun Laoghaire – Rathdown County Councils have shown the presence of misconnections from domestic properties with around 1 in 12 of the several hundred premises visited so far having misconnected drains.
"While work is continuing to rectify these problems, it could take several years to cover the large housing estates in both regions. Studies have also been undertaken to assess the impacts of the large numbers of seabirds known to congregate on Merrion and Sandymount beaches."
Peter Webster, EPA Senior Scientific Officer said: “Ireland has many beautiful beaches and some inland bathing waters with excellent water quality. The report covers the 142 EU identified bathing waters.
"It also provides details of over 80 other waters where bathing occurs and which are monitored by local authorities. While these 80 waters are not covered by the Regulations they are monitored by the local authorities because bathing or recreational activities are known to take place there and it is important to let the public know about their water quality.
"We would like to see many of them in the national monitoring programme in the future.”
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