The Irish Times view on water pollution: A public health concern

Ireland is the worst country in the EU for levels of a nasty type of E.coli in our waterways

The extent to which a nasty form of E.coli bacteria has been found in Irish beaches, rivers and lakes is a major public health concern. That the locations are popular with bathers and already deemed to have excellent water quality calls into question current testing criteria for waterways, both at national and European level.

Moreover, the researchers at NUIG School of Medicine note Ireland is the worst country in the EU for levels of Shiga-toxigenic E.coli (known as STEC), which arises from farm animal wastes and human sewage – with infection rates up to 10 times the European average. The bug can cause severe intestinal infection, renal failure and even death, while people with weakened immune system are especially vulnerable.

The scientists tested water samples at 75 sites used by people for bathing and recreation between December 2018 and October 2019. A total of 49 (65 per cent) showed up positive for the presence of the disease-causing strain of the bacteria. More than nine in 10 of river samples were positive, as were 75 per cent of lake samples and more than half (56 per cent) of seawater samples.

Such a high occurrence underlines the need for further investigation to establish the scale of the problem – not only in Ireland but globally as bathing waters in Europe and elsewhere are not routinely monitored for STEC. Irish bathing water quality is assessed annually based on the estimated total number of E.coli in a 100ml sample between May to September. This study shows up the limitations of this approach.


Details of the 75 sites where water was sampled are not being published. It seems inevitable that many locations are well-known bathing spots, where large numbers of people congregate. Users are entitled to know the exact status of waterways they use regularly. Public health authorities and the EPA must provide that reassurance.

At too many locations around Ireland, untreated sewage or the contents of overflowing storm water tanks continue to be discharged into waterways, especially near larger urban centres.