First Calderdale project underway as part of Yorkshire Water’s £1.5bn storm overflow programme

Yorkshire Water has started its first storm overflow investment project in Calderdale, as it continues to progress its £1.5bn regionwide investment to reduce wastewater discharges into watercourses.   

The £2m project, on Syke Lane in Brighouse, will build 180m3 of storage – enough to hold 180,000 litres of wastewater - into the local network, via a pipe nest solution. This is the addition of extra pipework into the system to hold more wastewater, which will flow to the treatment site as usual. 

When the work is complete, there will be a reduction in storm overflow discharges into Syke Wells. 

Building additional capacity in the network will make it less likely that excess wastewater will be discharged from the combined sewer network during periods of heavy or prolonged rainfall.  

Martin Ineson, project manager at Yorkshire Water, said: “Our storm overflows are operating more than we, and our customers, would like, and we’re committed and focused on reducing the number of discharges taking place so that we can improve the health of our local watercourses. It’s brilliant to be getting our wider project underway in Calderdale.” 

Whilst Syke Lane marks the first scheme in Calderdale, there are already nine projects taking place in Leeds, five across South Yorkshire, and one in Bradford.  

Contract partners M Group are expected to complete the work in early 2027. The tank will be built on private land, just off Syke Lane.  

Martin added: “We’re working closely with our partners to ensure that we’re undertaking the work with as little disruption as possible to the community, but as always, we thank everyone for their patience while we deliver this important work.” 

The work builds on a previous £1.8m project at the Syke Lane storm overflow in 2024 – in which new surface water pipes were laid in order to reduce flow in the combined network, decreasing discharges. Discharges reduced to 32 in 2025 from 110 in 2023 – a reduction of 70%.  

By 2030, 19 storm overflows across Calderdale will have been upgraded. Starting the programme follows the signing of a landmark agreement with Calderdale Council to improve the health of the river Calder by working more closely together to tackle pollution, improve water quality, and support nature-based solutions across the Calder catchment.  

Storm overflows are designed to act as a relief valve for the combined sewer network, which carries both wastewater and surface water, during periods of heavy or prolonged rainfall. They discharge when the system is at capacity to prevent flows backing up and flooding homes and gardens. 

The £1.5bn Yorkshire-wide storm overflow investment programme, which will see improvements at over 450 overflows, follows a £180m investment over the previous two years that helped reduce discharges to watercourses by 12% in 2024 from 2023, and by a further 24.5% in 2025. 

Across Yorkshire, the need for storm overflows to operate will be reduced by building new: 

Surface water sewers, to separate surface water and wastewater so that wastewater networks aren’t impacted by bad weather 

• Underground storage tanks, to build additional capacity into the network 
• Nature-based solutions, to build additional capacity into the network 
• Sustainable drainage systems, to slow the flow of surface water into the combined network 

The storm overflow project is part of Yorkshire Water’s £8.3bn investment into its services and the environment over the next five years.