AQW 10767/22-27

Ms Claire Sugden
Independent
East Londonderry

Tabled Date: 24/04/2024
Answered On Date: 14/05/2024
Priority Written: No

Question:
To ask the Minister of Agriculture, Environment and Rural Affairs to detail (i) the volume of sewage spills into waterways in each of the past five years, broken down by location; (ii) the reasons behind these spills; (iii) the work ongoing and needed in future to avoid these spills; and (iv) the impact such spills are having on (a) wildlife; (b) the environment; and (c) water quality for bathing.

Answer:

My Department does not hold data on the volume of wastewater discharges into waterways from Combined Sewer Overflows (CSOs), Emergency Overflows (EOs) nor Wastewater Treatment Works (WwTWs). These storm overflows are designed to operate in heavy rainfall conditions, when the wastewater in sewer networks is significantly diluted with stormwater, thereby preventing out of sewer flooding in properties.

Climate change and heavy rainfall events exacerbate problems from sewerage infrastructure and agricultural runoff, presenting real challenges for both farmers, sewage infrastructure and water quality managers. The Northern Ireland Environment Agency (NIEA) is working with NI Water on its programme of installing and commissioning storm-overflow monitors and to ensure the data received is accurate and reliable. It is NIEA and NI Water’s intention to publish annual performance reports once accurate and reliable monitoring data is available.

It is recognised that both wastewater and agricultural run-off affect bathing water quality. Impacts of discharges from WwTWs contribute to excess nutrient loading (e.g. phosphorus), in our water environment and the above work will greatly assist in better understanding the impact of discharges on water quality and actions to address the issue.

My Department will also continue to conduct targeted studies to identify the sources at failing sites and ensure appropriate measures are implemented to improve water quality.