Persistent pesticide issues with water supply highlighted in report

Two of Cavan's 16 water supplies are under investigation by the EPA for “persistent pesticide issues”. In its latest assessment of public water supplies, the State's environmental watchdog identified the Cavan Rural Water Supply and the Cavan Belturbet supply among eight water providers across the country that had “persistent pesticide issues at end of 2019”.

Overall Cavan does well in the report with the 16 public supplies showing a compliance rate of 99.3% for microbiological compliance and 99.3% for chemical compliance.

The report notes that the infringements relate to the most commonly found pesticide (MCPA22), which is used for rush control in grassland.

The term ‘Pesticides’ includes a wide range of products, but in Ireland, it is herbicides that pose the greatest threat to drinking water.

At the end of 2019, the EPA was investigating 31 supplies serving just under 294,300 people, due to failures to meet the pesticide standard. That number is down from 42 supplies affecting 283,500 people at the end of 2018.

The eight supplies under investigation for persistent pesticide failures during 2019 also include two in Dublin, two in Cork and one in Galway.

Irish Water it is adopting a consistent approach in its response to pesticide failures in all parts of the country.

This includes restrictions in the use of pesticides in catchment areas. A catchment is an area of land around a river, lake or other body of water. Any activities that take place in a catchment have the potential to affect the water quality of the river, lake or other body of water.

The report states: “In the situation where catchment activities are not enough to resolve the pesticide issues at a supply, Irish Water must consider other options such as installing treatment processes for the removal of pesticides.”

Other issues identified in the Cavan water supply in the report were the problems experienced in the Cavan Bailieboro RWSS when it experienced elevated Manganese levels and the Swanlinbar PWS issues with elevated chlorine in the network.

The EPA issued 20 directions to Irish Water during 2019, compared to six in 2018.

The utility company received a direction for Swanlinbar, Cavan to provide an action programme, with a subsequent direction requiring implementation of that programme. Issues at the treatment plant gave rise to the need for a boil notice. The EPA then audited the supply and issued directions to ensure that the issues were addressed by Irish Water including that the utility provide updates to the EPA every three months on progress with the implementation of the National Disinfection Programme.

The National Disinfection Programme updates for 2019 provided by Irish Water state that site assessments were concentrated in counties Tipperary, Cork, Laois, Offaly, Louth and Meath.

Upgrade works were concentrated in Carlow, Kilkenny, Wexford, Kildare, Longford, Louth, Meath, Mayo, Sligo, Tipperary and Limerick. The remaining sites requiring assessments and upgrade works are concentrated in counties Cavan, Monaghan, Leitrim, Dublin, Laois, Offaly, Louth, Meath, Tipperary, Limerick, and Cork.