NI Water is continuing to advance its multi-million-pound 'Stormwater Separation Programme', an initiative designed to mitigate the risk of out-of-sewer flooding, enhance environmental performance, and unlock critical capacity within the wastewater network to facilitate new housing and economic development across Northern Ireland.

Over the last three years, NI Water has committed £5 million to these projects, working in close collaboration with its appointed framework partners: Atkins Réalis, AG Wilson Civil Engineering, and CivCo. The funding has supported extensive investigations to identify and prioritise areas where combined sewer systems can be separated for maximum effect, followed by the installation of dedicated new stormwater infrastructure.

Robert McLean, Senior NI Water Project Manager, explained the strategic importance of the project: "This long-term investment by NI Water is helping to modernise wastewater infrastructure in areas facing network constraints, creating additional capacity to support sustainable development while improving resilience for local communities during periods of heavy rainfall. "Much of the wastewater network serving residents and businesses across Northern Ireland is a combined system, meaning that stormwater from gutters, drainpipes and gullies is collected in the same pipes and transferred to a wastewater treatment works before being cleaned and returned safely to the environment. Stormwater does not require treatment and therefore removing it from the combined network not only delivers efficiencies for NI Water but in certain cases, it can unlock the potential for development and economic growth."

The programme follows a phased structure, starting with thorough early-stage investigations. Teams utilise CCTV surveys and detailed assessments of existing drainage networks to locate and fix historic misconnections prior to construction. This ensures only clean surface water is diverted away from the combined sewers, optimising both operational and environmental outcomes.

Since its launch in 2023, the programme has successfully redirected more than 166,000 square metres of surface water drainage out of the combined network. This intervention has significantly alleviated pressure on existing infrastructure and created the wastewater capacity required to support approximately 600 new homes across Northern Ireland.

While the installation of this dedicated infrastructure causes short-term disruption, towns and cities including Derry/Londonderry, Newry, Ballymena, Portadown, Belfast, Newtownabbey, Antrim, and Coleraine are already experiencing the long-term advantages. These include elevated network resilience, superior environmental protection, and enhanced developmental capacity.

McLean concluded: "This ongoing investment reflects NI Water's commitment to delivering essential infrastructure improvements that support local communities, protect the environment and enable long-term regional growth across Northern Ireland."