A £6.4m scheme which will extend and upgrade the Northumbrian Water wastewater treatment works in Kelloe, County Durham, is progressing following joint venture, Esh-Stantec, being appointed as design and build contractor after a successful tendering procedure.

The WINEP (Water Industry National Environment Programme) scheme is set to improve the performance of the treatment works, supporting better water quality in Coxhoe Beck, as well as other watercourses downstream.

Procured via Northumbrian Water’s Runway 3 Capital Construction Works Framework, the project will include the installation of an Aquazone chemical dosing delivery system, above ground stainless steel humus settlement tanks, a tertiary treatment plant, and a rising main delivering effluent from the existing biological filters to the new humus tanks.  A package plant will be used within the new tertiary treatment plant. This will include a Denora nitrifying submerged aeration filter and a Eliquo Hydrok Mecana pile cloth media filter.

Refurbishment and upgrade works will be delivered to the existing pyramidal flow primary settlement tank, the radial flow primary settlement tank, the existing interstage pumping station, and final effluent returns pumping station. The current humus settlement tanks and tertiary treatment plant will be decommissioned.

Esh-Stantec is a joint venture formed in 2015 by north of England contractor, Esh Construction, and Stantec, a global provider of sustainable design and engineering services, to deliver capital schemes through Northumbrian Water’s Water and Wastewater Infrastructure Framework. The joint venture secured a place on the Runway 3 Framework in 2021 following its success on the Runway 2 Framework. 

David Pratt, Esh-Stantec divisional director, said: “The project marks the first secured by Esh-Stantec via Runway 3, a framework which will help maintain and improve the water and wastewater treatment and network assets across Northumbrian Water’s operating areas.

“As with all Esh-Stantec schemes, we are committed to delivering a customer focused approach to ensure all residents are kept fully up to date with progress throughout. We will also work within the community to create a legacy through a programme of social value initiatives, including the delivery of STEM and employability sessions in local schools.” 

Scott Jackson, regional director of Stantec UK & Ireland, added: “What a fantastic start to our work on Northumbrian Water’s Runway 3 framework. We are passionate about using cutting-edge design thinking to help our clients provide real benefits for communities and this project ensures we do just that, while improving the water quality entering our watercourses.  

“Our designs will also support Northumbrian Water in improving levels of performance and efficiency, and we look forward to making the most of our expertise as this project progresses.”

Work started in October last year to stabilise the ground via probe drilling and grouting. Since then, underground interconnecting pipework has been installed along with enabling and excavation works to pave the way for the new tertiary treatment plant, humus tanks and rising main. The project is due to be completed in late spring 2024.