Advice issued as pesticides discovered in Offaly water supplies

Justin Kelly


Justin Kelly


Advice issued as pesticides discovered in Offaly water supplies

Advice issued as pesticides discovered in Offaly water supply

Exceedances of pesticides in water supplies are on the increase in Co Offaly with two instances of exceedances in 2018, one in the Clara Ferbane Public Water Supply (PWS) and one in the Tullamore North Public Water Supply.

"While there is no threat to public health, it is imperative that users of pesticides are mindful of best practice when spraying their lands," Irish Water has said.

Irish Water, working in partnership with the National Pesticides and Drinking Water Action Group (NPDWAG), is appealing to farmers and other users of pesticides to ensure that best practice measures to protect drinking water quality are always followed.

Efforts to reduce the incidence of detections are being coordinated by the NPDWAG which is chaired by the Department of Agriculture, Food and the Marine. All of the key stakeholders are represented in this group and include other Government departments and agencies; local authorities; industry representative bodies; farming organisations; water sector organisations; and amenity sector organisations.

These latest exceedances in Offaly follow on from previous exceedances noted in 2017 in the Clara Ferbane PWS.

Commenting, Andrew Boylan, Irish Water’s Regional Drinking Water Compliance Specialist said: “Irish Water is continuing its extensive investment programme to improve water and wastewater services in Ireland. Providing safe, clean drinking water for all is our first priority. In Ireland, the majority (82 per cent) of drinking water supplies come from surface water sources (water from rivers, lakes and streams). Such supplies are vulnerable to contamination from land and animal run-off.”

Two different supplies in Offaly have seen the herbicide MCPA and also Mecoprop, Triclopyr, Fluroxypyr and Glyphosate detected over the past two years, albeit mostly at very low levels.

Dr Aidan Moody, Chair of the NPDWAG commented: “The continued engagement of all stakeholders, working in partnership, is needed to tackle this issue. Users of pesticides should make sure that they are aware of the best practice measures that should be followed to protect water quality.”

"MCPA, which is commonly used to kill rushes on wetland, is the main offender. Careless storage, handling or improper application means it can easily end up in drinking water leading to breaches of the drinking water regulations."

"The regulations are so stringent that a single drop of pesticide is enough to breach the drinking water limit in a small stream for up to 30 kilometres. This clearly highlights the level of care needed to protect drinking water sources."

"Irish Water, working in partnership with the National Pesticides and Drinking Water Action Group, would like to remind farmers and professional users of pesticides of the need to follow best practice in the application of pesticides such as MCPA on land, particularly near lakes and rivers used as drinking water sources."

The basic steps in reducing pesticide risks are –

- Choose the right pesticide product (Note that products containing MCPA are NOT approved for use in weed-wipers.)
- Read and follow the product label
- Determine the right amount to purchase and use
- Don’t spray if rain or strong wind is forecast in the next 48 hours
- Make sure you are aware of the location of all nearby watercourses
- Comply with any buffer zone specified on the product label to protect the aquatic environment. Mark out the specified buffer zone from the edge of the river or lake or other watercourse
- Never fill a sprayer directly from a watercourse or carry out mixing, loading or other handling operations beside a watercourse
- Avoid spills, stay well back from open drains and rinse empty containers 3 times into the sprayer.
- Store and dispose of pesticides and their containers properly.

A recently produced video on the correct use of MCPA can be viewed on Irish Water’s YouTube channel here.

Information leaflets on pesticide use are also available to download from the Teagasc website at