The team behind London’s new super sewer are another step closer to delivering the tunnel following the completion of the final section of secondary lining. 

Tideway’s tunnel boring machines finished excavating the main tunnel in the spring of 2022, but a secondary concrete lining was required to give added strength and durability. 

With the most eastern section of the tunnel between Bermondsey and Stratford finished last week, secondary lining is now complete on all 25km of the super sewer.

This brings the Tideway project one step closer to delivery, as it looks ahead to activating the tunnel next year – diverting sewage away from the Thames and into the tunnel for the first time.

Gareth Howells, Tideway’s Project Manager for the tunnelling works in the eastern section of the project, said: “Completing the secondary lining is key construction milestone for this project, but more than that, it’s an important moment for London as we look toward a cleaner healthier River Thames.

“Our work underground is largely complete, and this month we’ve also seen the full above-ground work finished and reopened at two sites in west London.

“We’re now focussed on harnessing this momentum and delivering a cleaner river from next year when, for the first time, this key piece of infrastructure will begin diverting sewage away from the Thames.”

Primary lining for the 7.2m internal diameter super sewer was created using four giant tunnel boring machines, while two smaller machines built the network’s two large connection tunnels in Greenwich and Wandsworth.

Richard Holbrook, Project Director for the eastern section of the project, added: “Our teams in the eastern section have done a fantastic job constructing this key piece of London’s new infrastructure. 

“Although there remains a lot of important work to be done, we’re looking ahead to finishing the job and creating a healthier environment in London for many generations to come.”

The completion of secondary lining in the main tunnel follows the reopening of two Tideway sites in west London – Putney and Barn Elms.

A joint venture between Costain, Vinci Construction Grands Projets and Bachy Soletanche is delivering the eastern section of the super sewer project.