Protecting drinking water from pesticides


Consider non-chemical outdoor maintenance methods:

Leitrim County Council would like to remind householders, the farming community, greenskeepers, sports groundskeepers and professional users of the need to consider very carefully their use of pesticides in the management of outdoor areas.

We encourage those maintaining outdoor areas to consider pesticide use as a last resort i.e. consider non-chemical methods (manual/mechanical - drainage, liming, topping/cutting, hoeing, hand-pulling, rotavating, weed suppression, mulching, no-dig gardening methods) instead of or in tandem with pesticides. See the Green Gardening document for garden hints and tips.

The use of pesticides and any careless storage or handling can very easily cause breaches of the legal limit for drinking water. A single drop of herbicide can breach the drinking water limit in a small stream for 30km!

Pesticide exceedances have been detected in Leitrim Drinking water supplies and while the levels are not considered a threat to public health their presence in water is very undesirable.


We encourage users to consider, in each case, if pesticides are needed at all. Leaving areas unsprayed can help native flowering plants to grow and support a range of insects including bees and other vital pollinators. One third of Irelands bee species are threatened with extinction and by helping the bee population to survive and thrive we are also protecting precious water resources. For more information on practical ways to help bees and other pollinators, check out the All Ireland Pollinator Plan at


Where pesticide application is considered the last resort users must follow best practice in application and particularly near water including any drain, stream, lake, river or drinking water source.

Best Practice:

·        Know the location of drinking water sources and abstraction point.

·        Ensure strict compliance with safeguard no–use zones around abstraction points.

·        Read and follow the product label and product instructions.

·        Determine the right amount to purchase and use.

·        Be sure to choose the right pesticide product.

·        Only apply chemical control when the target weed is growing.

·        Store pesticides in a manner which is secure, dry and cannot result in accidental releases.

·        Take extreme caution during mixing and preparation of pesticides to avoid spills/ dripping and to reduce washings and wastewater from the handling area.

·        Note it is illegal to fill a sprayer/ equipment directly from a watercourse.

The Best Practice Guidance was prepared by a multiagency group convened by the Environmental Protection Agency including Department of Agriculture, Food and the Marine and farming representative groups.

MCPA: At this time of year, we are promoting the safe use and particularly with regard to MCPA. MCPA is the active substance present in many commonly used herbicide products. It is used on grassland and targeted at thistle, docks and rushes. MCPA is the most commonly detected pesticide in Ireland. It is very soluble, highly mobile and can easily leach from soil into water. MCPA is restricted for use between March and September only and is not approved for use in weed lickers/wipers or knapsack sprayers. It should be noted that to use a weed licker, users must be registered as a Professional User (PU) and hold specialist training.

Where MCPA is targeted at controlling rushes the Department of Agriculture Food and the Marine has developed new guidance on the sustainable management of rushes. The new approach is based on the concepts of containment or suppression and aims to minimise MCPA use while tackling the  rush problem. Further information is available at


‘Don’ts’ when using pesticides:

Don’t fill spraying equipment directly from a drain stream river or lake.

Don’t perform pesticide handling operations (filling, mixing or washing of the sprayer) near water, open drains or well heads. A distance of at least 10m should be maintained and preferably 50 meters where possible.

Don’t spray if the target area is wet or heavy rain is forecast within 48 hours.

Don’t apply pesticides during windy conditions.

Don’t apply pesticides near open drains wells or springs.

Don’t apply pesticides on waterlogged or poorly draining soils that slope steeply towards a waterbody or on any other vulnerable area that leads directly to water.

Don’t discard washings from application equipment down a drain or onto an area from which they can readily enter a waterbody.

Regulation: The Pesticide Registration and Controls Divisions and the Pesticide Control Laboratory of the Department of Agriculture, Food and the Marine (DAFM) are responsible for implementing the regulatory system for plant protection and biocidal products (these latter include disinfectants, preservatives, pest control products, antifoulants, etc.). The Divisions are also responsible for the National Regulations controlling pesticide residues in food.

SUDS: The Sustainable Use of Pesticides Directive (SUD) establishes a framework for European Community action to achieve the sustainable use of pesticides by setting minimum rules to reduce the risks to human health and the environment that are associated with pesticide use.

Safe Guard Zones: Pesticide Users are obliged, at all times to protect water. This includes complying with safeguard zones around drinking water. Safeguard zones are no spray buffers. They vary in size depending on the classification of the water source. A chart of water sources and the associated safe guard zones can be found at


Further Information: Information leaflets on best practice in the use of pesticides to protect water are available from Leitrim County Council 071 96 20005 ext. Environment or available for download at

There are a series of three leaflets covering pesticide use and water quality

·        Protecting Drinking Water from Pesticides- Advice for Farmers and Other Professional Users.

·        Protecting Drinking Water from Pesticides- Advice for Gardeners and Household Users.

·        Protecting Drinking Water From Pesticides- Herbicide Use in Grassland.

  • EU Sturctural Fund
  • European Union
  • Leitrim Sports