Pesticide users urged to 'think before you spray'
The National Pesticides and Drinking Water Action Group (NPDWAG) and Uisce Éireann are encouraging all pesticide users to help maintain the progress made in protecting Ireland’s drinking water.
Since 2017, the number of pesticide exceedances detected in public drinking water supplies has dropped by more than 50%.
The NPDWAG said that this improvement reflects the commitment of farmers, landowners and amenity managers to reducing pesticide use and following best practice.
However, the group warned that recent monitoring shows there is still work to be done.
Dr Pat O’Sullivan, Uisce Éireann’s crinking water compliance senior manager, said that last year saw "a worrying number of pesticide detections occurring outside the main spraying season for MCPA".
"While this has not yet happened in 2025, the risk of it repeating itself remains high.
"We are urging all pesticide users to be mindful of their use as the spraying season comes to a close, so that we can avoid late-season exceedances again this year.
"Even one drop of pesticide can travel up to 30km in a watercourse, so every action counts," he added.
The Department of Agriculture, Food and the Marine (DAFM) leads the NPDWAG, which includes government agencies, local authorities, industry bodies, farm organisations, along with water and amenity sector organisations.
Dr Aidan Moody from DAFM who is the chair of NPDWAG acknowledged the "excellent work" by farmers and land managers to reduce pesticide use and to follow correct application methods.
"We urge everyone to continue the great work and always consider whether a pesticide is needed at all, and where it is, to make sure that best practices are followed.
"This approach not only protects our drinking water but also supports biodiversity and healthy ecosystems," he said.
Pesticide users should note that a closed spray period is specified on the label of some products, during which product use is not allowed.
This is because late season applications, combined with wetter autumn and winter conditions, increase the risk of pesticides reaching drinking water sources.
The NPDWAG issued the following reminders for all pesticide users:
- Only use pesticides when necessary and after considering all alternative control methods;
- Always read and follow the product label;
- MCPA products are not allowed to be used from the end of September (or the end of October, depending on the particular product) to the beginning of March;
- Do not use pesticides if rain is forecast in the next 48 hours;
- Keep well clear of watercourses, drains, wells and springs, and observe the correct no-spray buffer zones;
- Avoid spills. Never fill or wash sprayers beside drains or on concrete where runoff can occur. Triple-rinse containers into the sprayer;
- Dispose of unused product and containers safely.
The most frequently detected pesticide substance in Ireland's drinking water is MCPA, an active substance in many commonly used herbicide products to control thistle, dock, and rush.
