To ask the Minister for Infrastructure,pursuant to AQW 18019/17-22, for her assessment of the risks to (i) public health; and (ii) the environment from identified sewage overflow incidents.

Sewage overflow incidents are operational matters for NI Water and any associated risks, and consequences, are for it, and its environmental regulators, to mitigate against and address. The Northern Ireland Environment Agency (NIEA) is responsible for protecting public health and the environment by providing effective and efficient regulation and enforcement of water supplies. Responsibility for the regulation of discharges from the Larne Sewage Network falls under the remit of the NIEA. A number of measures including legislative requirements, have been put in place by both NI Water and NIEA to mitigate risks associated with sewage overflows in the Larne area

NI Water has advised that sewer networks have a finite capacity and are designed to overflow to relieve pressure on the system. The overflow is released through safety valves or Combined Sewer Overflows (CSOs) which flow into the receiving freshwater or marine environment. The CSOs operate on a sewer network during periods of storm/ extreme wet weather and bring significant dilution in the receiving environment, which minimises the risks to the environment, The CSOs are also to stop the internal flooding of households and businesses with sewage which would present a risk to public health.

The NIEA is responsible, under the Urban Wastewater Treatment Directive, for protecting the environment from the adverse effects of urban wastewater discharges. I understand that the NIEA is currently engaging with NI Water in relation to a number of improvements required to the sewerage network in the Larne area. These improvements are intended to mitigate any risks to neighbouring bathing and shellfish waters and reduce the impact of sewage spills from the sewer network.