Rise in instances of pesticide in drinking water

Uisce Éireann detected 66 cases of pesticides that exceeded allowable amounts in drinking water last year, marking an increase on the 52 exceedances recorded in 2023.

The incidents were not a threat to public health, according to the National Pesticides and Drinking Water Action Group (NPDWAG), which is part of a coalition now urging farmers, gardeners, and those maintaining sporting facilities to use alternatives to pesticides or to ensure they are used responsibly.

The number of pesticide exceedances in public drinking water supplies in Ireland has decreased by more than 50% since 2017.

However, the NPDWAG, which is co-ordinated by the Department of Agriculture, Food & the Marine, reminded users of herbicides and pesticides to always take account of the vulnerability of their local drinking water supplies when making decisions about their possible use, and to be aware of how their actions could impact drinking water.

Pat O’Sullivan, Uisce Éireann’s drinking water compliance senior manager, emphasised the need for collective action.

“Last year, we detected pesticide exceedances 66 times in 22 public drinking water supplies,” he said.

“A concerning trend is the number of exceedances outside the spraying season for certain plant protection products, particularly in winter.

“We want to remind users to be mindful of water sources when using pesticides, as one drop of pesticide can be detected in a stream up to 30km away.”

Aidan Moody, chair of NPDWAG, said everyone had a part to play in protecting drinking water quality.

“Users of pesticides must always consider the possibilities for alternative control methods in the first instance,” he said.

“If pesticide application is considered essential, ensure they follow best practices to protect water quality.”