The company took just five weeks to complete the drive for Northumbrian Water. TBM Penelope started at the base of the 46m-deep east shaft in April, reaching the 32m-deep west shaft last week.

The tunnel is part of Northumbrian Water’s £155m Project Pipeline: County Durham and Tees Valley which involves the construction of approximately 57km of new pipes connecting Lartington Water Treatment Works.

The TBM will now be lifted out of the shaft so Farrans Construction and subcontractor Joseph Gallagher can start on the next phase.

This will include sealing work before twin water mains are installed horizontally through the tunnel. Putting two mains through the tunnel adds resilience to the investment, ensuring a back-up is available in case of any problems.

Phase 1 of the project will connect Lartington, in Upper Teesdale, with Whorley Hill and Shildon, County Durham. It will be followed by a second phase extending the pipeline from Whorley Hill to Long Newton, connecting to the existing network that serves large parts of Teesside.