Work to start on Ilkley’s Middleton storm overflow to reduce river Wharfe discharges

7/7/2025
Yorkshire Water will begin upgrades at the Middleton sewage pumping station combined storm overflow (CSO) in Ilkley next week as part large-scale investment to improve bathing water quality in the river Wharfe.
The £7.9m project at Middleton CSO follows is being carried out by contract partners M Group and will begin work on 10th July. The scheme includes the construction of a 920m3 storage tank in the field adjacent to the Olicanian Cricket Club.
The project will reduce the number and volume of discharges from the CSO to one discharge per bathing season and no more than 10 discharges per year on average. Discharges occur during heavy or prolonged rainfall to prevent wastewater backing up and flooding nearby homes and businesses.
To enable the construction work to take place, a number of temporary site access roads will be created off Denton Road and will be controlled with a set of two-way lights for approximately ten months.
The project at Middleton sewage pumping station CSO follows a £9.7m storage tank project at Addingham and Low Mill Lane storm overflows.
Both projects will reduce storm overflow discharges into the river Wharfe to one discharge per bathing water season and no more than 10 discharges per year on average. The additional storage will hold excess flows of wastewater during periods of wet weather, reducing the likelihood of discharges, before the excess flows are returned to the sewer network for full treatment.
Further work will take place later this year at Bridge Lane storm overflow.
Dominic Cunney, project manager at Yorkshire Water, said: “We have been investing significantly in our wastewater network in and around Ilkley to do our bit to improve the quality of the water in the river Wharfe. Part of this work is targeting the storm overflows that are just upstream of the bathing water so that we can bring down the number of discharges – Middleton is just the latest one to see these upgrades.
“The work on these overflow will complement work already completed in Ilkley and the £60m project underway at Ilkley wastewater treatment works, all of which have been designed to reduce overflows entering the Wharfe.
“We appreciate that the lights on Denton Road will be in place for a lengthy period, but would like to assure everyone in the area that we have worked with Bradford Council to ensure we’re working in the least disruptive way possible. We thank everyone in the area for their patience and understanding whilst we complete this important project.”
These schemes follow previous works to reduce discharges from Ilkley wastewater treatment works and Rivadale View CSO and the ongoing £60m investment at Ilkley wastewater treatment works, which includes
- More than doubling the capacity of the Ilkley Wastewater Treatment Works by installing a large storm water storage tank and constructing a new aerated rush bed in its grounds
- Plans for a 19,000m2 integrated wetland across the river from the treatment works to provide further treatment to the final effluent and a biodiversity net gain for the area, subject to planning permission