THERE HAS BEEN an increase in the number of drinking water supply samples that exceed legal limits for pesticides.

Uisce Éireann’s public water supply monitoring programme found 66 exceedances in 2024 from more than 34,000 analyses, compared to 52 exceedances in 2023.

The pesticide levels detected in the monitoring programmes do not pose a risk to health, the body said.

These include herbicides such as MCPA, which is used to control dock and thistle, and in Ireland is commonly used to control rushes – meaning it’s used close to water courses. As it’s water soluble, it’s more prone to leaching and run-off to nearby water bodies.

There have been recurring cases of samples coming back with high levels of pesticides in Hacketstown, Co Carlow, Greenmount, Co Louth and Foynes Shannon Estuary, Co Limerick.

These areas will be the subjects of targeted action now, the likes of which Uisce Éireann says was successful in reducing pesticides found in water in Belturbet, Co Cavan and Newport, Co. Mayo.

It added that while the overall compliance rate remains “very high”, all stakeholders should stay vigilant to protect drinking water quality.

These include Uisce Éireann itself, as well as other state bodies related to water, agriculture and health, such as the HSE and the Irish Farmers’ Association.

Uisce Éireann and the National Pesticides and Drinking Water Action Group are urging farmers, greenkeepers, amenity users and domestic pesticide users to carefully evaluate the necessity of using pesticides.

“Pesticides should only be applied when essential and after considering alternative methods.”

As well as improving water quality, minimising pesticide use can allow native flowering plant species to grow, which in turn supports insects, including bees and other important pollinators.