Northumbrian Water engineers working on an £18 million project in a County Durham village are trialling an innovative solution to help protect and improve the region’s rivers, streams and coast.

The water company is working to reduce spills from ten storm overflows (SOs) in the Stanley area, protecting the Stanley Burn and watercourses downstream.

Working alongside partners Esh-Stantec, the water company is using its work on the first of the SOs to explore the potential benefits of using recycled plastic containers in place of traditional methods of increasing storage in its network.

It’s hoped that the trial might prove the concept’s ability to become an easily replicable lower carbon solution, compared with installing traditional concrete storage or additional, larger pipework. If successful, the modular storage containers could be installed at other suitable sites across the region, at a lower cost and with reduced disruption for local communities.

The idea came from Northumbrian Water’s 2025 Innovation Festival and takes a solution currently used to reduce surface water flooding, and adapting it to combined sewers, which carry both rainwater and sewage.

The box would hold back water at times of heavy rainfall, reducing the likelihood of a spill to the watercourse, and then return the water to the network when flows have decreased and there is capacity in the sewers.

David Groark, Project Manager at Northumbrian Water, said:

“There is real potential in taking this idea from surface water management and adapting it for use in combined sewers, at a time when we are investing heavily in a £1.7bn programme of work to benefit the environment.

“Not only is this a lower carbon solution than installing concrete storage tanks, the installation process is quicker, meaning we are working in communities for shorter periods of time, which also has a cost saving. If this trial shows that this is a successful, effective solution to reducing spills, we can start to look at other storm overflows to see where else this could be used.”

Tim Cutter, Principal Engineer, led the process of taking the festival idea and developing it to be trialled in Stanley. He said:

“If this trial shows the benefits we hope for, these containers are easily and quickly sourced, and it’s likely they would be best suited where smaller volumes are required, such as the 60m3 being installed at Stanley. It’s possible they may also be able to provide a solution in other parts of the network as well, such as at the inlets to sewage treatment works, protecting those during heavy rainfall.”