NI Water has appealed to farmers, land managers, contractors and domestic users to exercise extra caution when using plant protection products on rushes and weeds during late summer, when spraying is commonly carried out.

The company warns that small drips and spills during preparation, application, disposal of chemicals, or when washing down equipment, can rapidly enter drains and flow into streams, rivers and lakes, particularly after heavy rain. Many of these watercourses provide raw water for treatment and public supply.

By taking simple precautions, users can help prevent plant protection products from entering the water environment, safeguard local wildlife and support the continued delivery of safe, wholesome drinking water.

Roy Taylor, NI Water Catchment Manager, said: "Our monitoring shows that MCPA is commonly detected in watercourses during the application season, particularly in April/May and often again in September. This is the time of year when many farmers are treating rushes and weeds in grassland, and when householders may also be using products to control weeds in gardens.

"Many of these products contain MCPA, a broadleaf herbicide which remains one of the main challenges for protecting raw water quality in Northern Ireland. Because MCPA is highly soluble and can remain in surface water for a long time, it is difficult and costly to remove at the water treatment stage. "NI Water works hard to remove substances such as MCPA to meet drinking water standards and provide safe, wholesome drinking water for customers. However, the best outcome for everyone is to prevent these products entering rivers and lakes in the first place.

"MCPA loss from land also represents wasted product and a financial loss to farm businesses. It can also pose a risk to the water environment and to the plants and animals that depend on it. We all have a part to play in protecting our precious drinking water resources."

NI Water is part of The Water Catchment Partnership, which includes the Ulster Farmers' Union, DAERA, CAFRE, Armagh City, Banbridge and Craigavon Borough Council, Translink and the Voluntary Initiative. Since 2013, the partnership has promoted best practice in pesticide use, with a particular focus on reducing MCPA levels in local watercourses.

Recent actions by NI Water include the Farming for Water Seagahan scheme, offering farmers and landowners within the Seagahan drinking water catchment 100% funded measures to cut MCPA, nutrients and soil reaching nearby watercourses. Building on the success of the nearby Clay Lake scheme, it supports practical on-farm improvements that benefit both farm businesses and water quality in Seagahan reservoir.

By helping farmers implement small changes across the catchment, the Farming for Water scheme aims to support more sustainable agriculture while also helping to reduce the cost of treating and supplying high-quality drinking water. Details and application information are available at www.niwater.com/farming-for-water.