Groups urge action as wastewater capacity holds back 55,000 homes in Northern Ireland

The lost opportunity in housing construction is estimated to be nearly £4bn over the next 14 years, out of a near-£11bn economic hit.

The report pointed out that the delay to housebuilding is happening at a time of “acute housing need, rising affordability pressure and a continuing concern about the pace of new housing”. 

In May, the number of households experiencing homelessness in Northern Ireland reached 33,400 – up 5% on the previous year and double the number in 2016.

According to the latest figures, there are more than 50,000 households waiting for a social home and over 5,600 are in temporary accommodation, including 4,800 children.

But government grant levels for social housebuilding are insufficient to support the country’s ambitions, according to communities minister Gordon Lyons.

Last month, he revealed that he would be drawing up plans with officials to use public land for social homes in a bid to plug the gap.

Yet, the WIG report highlighted that some areas of the land identified for future development by councils are already affected by wastewater constraints.

In Belfast, 71% of land in the local development plan is affected by closed catchments, areas with strict limitations on how sewage and wastewater can be managed, treated and discharged.

This would affect potentially 14,300 new homes, nearly a quarter of the total housing ambition of the seven Northern Irish councils that have released their local development plans.

Mid and East Antrim Council is also hard hit by pressure on its water system, affecting half of its potential development sites.

The authors of the report acknowledged that there has been some government progress on wastewater funding. Nearly £30m in extra investment has unlocked nearly 5,300 homes since autumn 2024.

But they said a “credible recovery approach” to improving the system must be multi-year and move beyond short-term allocations. 

The report proposed securing funding from the UK government, reducing pressure by bringing forward sustainable drainage solutions (SuDS) legislation, and bringing in a progressive household levy to tackle the infrastructure deficit and voluntary contributions from developers.

Justin Cartwright, Northern Ireland national director at the Chartered Institute of Housing, a co-sponsor of the WIG report, said: “Northern Ireland can continue to manage constraint – leaving thousands on housing waiting lists – or it can choose recovery and growth.

“With the right funding model, clear delivery plan and political commitment, wastewater infrastructure can become an enabler of growth, housing, environmental improvement and regional balance.”

Mark Spence, chief executive of the Construction Employers Federation, said on behalf of the organisation: “Wastewater infrastructure is now one of the most significant constraints on Northern Ireland’s construction sector.

“This is not simply about pipes and treatment works. It is about whether we can build the homes people need, support business growth, regenerate our towns and cities, and protect our environment.”

Responding to Inside Housing, the Department for Infrastructure confirmed plans to bring forward SuDS legislation, voluntary developer contributions and secure more investment from the Northern Ireland Executive to tackle the issue.

But a spokesperson for the department said Liz Kimmins, minister for infrastructure, will not be bringing in a proposed levy and blamed historic underfunding by the UK government for the current situation. 

The spokesperson said: “Evidence from England and Wales also suggests that significant pressures persist under any alternative models that include water charging, in respect of wastewater capacity and environmental impacts.

“Instead, she [Ms Kimmins] is continuing to deliver the three-pronged approach to unlock additional wastewater capacity and support housebuilding by securing more investment for wastewater infrastructure from executive colleagues, bringing in legislation to provide for sustainable drainage systems, and the introduction of voluntary developer contributions.

“She also recently secured executive agreement that wastewater infrastructure should be prioritised for investment as it cuts across multiple ministers’ roles.”