Pesticides in Water Sources

A pesticide is a substance that prevents insects, weeds and other pests from harming plants. Pesticides are used in many sectors, including:​

• agriculture
• transport
• forestry
• amenities (e.g. public parks, golf courses)
• domestic gardens

While pesticide use is common, using, storing and disposing of pesticides in the wrong way can cause harm. Mismanaging pesticides can pollute surrounding environments and our drinking water sources. That's why pesticide use is strictly regulated in Ireland under the Sustainable Use of Pesticides Regulations.

Pesticides and water sources

Uisce Éireann regularly monitor pesticide levels in drinking water samples to makes sure that standards are met. Through monitoring public water supplies, some samples have been identified as having pesticide concentrations that are above our drinking water standards.

According to World Health Organisation (WHO), these levels of pesticide concentration are not a concern for public health. However, conventional water treatment processes are not designed to remove pesticides from source water. That's why it's important to understand how pesticide use in water catchments can affect our water quality. This way, we target the issue of contamination at its source.

Watch our video below to learn more about protecting water sources from pesticides.

National Pesticides and Drinking Water Action Group

We also work closely with the National Pesticides and Drinking Water Action Group (NPDWAG). Our work with NPDWAG includes a focus on preventing and monitoring pesticide contamination in water catchments across Ireland.

Advice on using pesticides

Uisce Éireann in partnership with organisations involved in NPDWAG is working towards a reduction in pesticide use. We urge the farming community, greens keepers, grounds keepers, as well as domestic users of pesticides, to consider in each case whether they need to use pesticides at all.

Minimising pesticide use not only helps to protect water quality but also has environmental benefits for biodiversity.

Using pesticides safely

Sometimes, pesticide use is hard to avoid. When using pesticides, it's important to follow best practices. We have dedicated tips for pesticide use in farms, grasslands and household gardens. For more information, download the leaflets below.

• Advice for farmers and professional users
• Advice for herbicide use in grassland
• Advice for gardeners and household users

Other helpful resources for following best practice when using pesticides include:

• Guidance for empty containers:
  • Container Triple Rinse Guide
  • Empty Pesticide Containers Guide
• Alternatives to Pesticides
• Agriculture and Food Development Authority (Teagasc)
• Department of Agriculture, Food and Marine (DAFM)
• Environmental Protection Agency (EPA)