Yorkshire Water starts work to build two more storm overflow projects in Temple Newsam and Armley
12 storm overflow discharge reduction projects are being built in Leeds
Yorkshire Water has started work on the construction of two more storm overflow projects in Leeds.
The latest projects, which form part of a £1.5bn investment to reduce the number of discharges, will see additional storage built into the sewer network on Temple Avenue, near Temple Newsam, and Canal Road in Armley.
Contract partners M Group are expecting to complete the Temple Avenue project in November 2026, and the Canal Road project in spring 2027.
Taking the running total number of projects in Leeds to 12, the £5.7m investment on the two newest sites will create 547m3 of capacity into the sewer network – enough to hold 547,000 litres of wastewater and rainwater during periods of heavy or prolonged rainfall.
Lydia Mitchell, project manager at Yorkshire Water, said: “These two schemes getting underway means that there are now 12 storm overflow projects in total taking place across Leeds.
“Storm overflows are operating more than we or our customers want, but we’re making real progress in our drive to bring the numbers down across Yorkshire. By 2030, we’ll have upgraded over 450 of our overflows.”
At Temple Avenue combined storm overflow (CSO), 360m3 of pipe nest storage will be built into the network. This is the addition of extra pipework to hold more wastewater prior to treatment, reducing discharges into Wyke Beck.
In Armley, a 187m3 underground storage tank will be installed to reduce discharges from Canal Road CSO into the river Aire. Storage tanks build additional capacity into the network, holding excess wastewater during periods of bad weather to prevent it from being discharged.
Flows are sent for full treatment when capacity in the network has returned to normal level.
Other projects are underway in Leeds are:
- Haigh Park Road, Stourton
- Millshaw, Beeston
- Kirkstall Cricket Club
- Wyther Lane, Kirkstall
- Village Place, Burley
- Spen Lane, Headingley
- Fraser Avenue, Horsforth
- Sussex Avenue near Hunslet
- Jack Lane, also near Hunslet
- Newlay Grove, Horsforth
Once complete, the projects will contribute to reducing the number of discharges from overflows in Leeds by 72%, by 2030. Elsewhere in Yorkshire, there are schemes underway in Sheffield, Barnsley, and Bradford.
The overall £1.5bn investment programme follows a £180m investment over the previous two years, which helped reduce discharges to watercourses by 12% in 2024, compared to 2023, and by a further 24.5% in 2025.
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.
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