New sewer to be laid in Ilkley using trenchless technology

Work is due to begin in Ilkley to lay a new sewer under the A65 to help reduce the frequency and volume of storm discharges into the river Wharfe during periods of heavy or prolonged rainfall.

Yorkshire Water’s partner Ward and Burke will begin work on 17 November, setting up site working areas ahead of construction. Trenchless technology will be used with underground boring machinery controlled remotely throughout the project to keep disruption to a minimum while laying 800m of new sewer under the A65 to the Sewage Treatment Works.

This reduces the need to close the road as it lays pipework behind it and sends the earth back to the staging site where it is cleaned and recycled for use in other projects in the area.

The sewer will operate as additional storage during periods of heavy rainfall or prolonged rainfall to reduce the frequency of discharges from Rivadale storm overflow by 40% and halve the volume of wastewater discharged during those events.

The initial stage of the work will include laying the sewer between Yorkshire Water’s Ilkley wastewater treatment works and Ashlands playing fields. The second stage of the project is to lay the sewer under the A65. Remote-controlled tunnelling equipment will be used at depths of 5-8 metres below the ground, to bore the hole for the new sewer.

The equipment will be recovered at the Ilkley Wharfe View car park once the sewer has been laid.

Ben Roche, director of wastewater at Yorkshire Water, said: “This project forms a major part of our investment in Ilkley following the creation of an inland bathing water on the Wharfe in the town. Laying a new sewer to accommodate higher flows of wastewater during periods of heavy and prolonged rainfall will ultimately reduce the number and volume of discharges from Rivadale CSO, helping to improve water quality in the Wharfe.

“We’ve worked very closely with Bradford Council highways teams to keep the disruption for our customers to a minimum. As a result, we’re making use of trenchless technology, with equipment boring the hole and laying the sewer remotely, preventing the need to dig up the A65 to complete this work. For the majority of the project, there will be limited signs of our activity underground.

“We completely understand the increased public interest in river quality in our region and it’s an issue that must be addressed by a range of agencies working together. We continue to invest over and above existing investment plans in Ilkley and the surrounding area to make improvements on our network to reduce its impact on water quality. Water companies have a key role to play, but coordinated action is needed by farmers, the local authority, businesses and local people with the ultimate aim of improving the bathing water classification.”

To allow the equipment to be controlled and recovered from underground, part of a Ashlands playing fields will be turned into a working compound and the Ilkley Wharfe View car park will be closed. Yorkshire Water is working with Bradford Council to develop alternative parking arrangements.

The project is expected to be completed in January 2024.