Tideway completes 80% of tunnelling

Around 80 per cent of the tunnelling has been completed on the Thames Tideway Tunnel with more than 19km of work completed.

Drilling has begun on the final major connection tunnel between Greenwich and Chambers Wharf to connect the 4.5km section of the super sewer.

Tunnel boring machine (TBM) Ursula completed tunnelling on the central section of the upgrade the capital’s sewer network, which is being undertaken to meet the demands of the 21st century and booming population

Ursula completed its 7.6km journey from Battersea to Bermondsey and this week broke into the deep shaft at the Chambers Wharf site.

Elsewhere, TBM Annie started the excavation towards Bermondsey with the building of rings to support the sewer as it progresses.

Darren Kehoe, project manager at Greenwich who is overseeing boring machine Annie’s progress, said: “We’ve overcome many challenges getting to here and I’m proud of the team for their dedication and diligence in reaching this point.”

The latest pushes involved more than one million tonnes of soil being excavated and transported by barge up the river.

Tim Newman, Tideway’s project geologist, described the completion of the longest single drive as “a wonderful milestone” during a challenging year.

He said: “TBM Ursula has tunnelled at incredible depths, encountering a real mix of geology – through clay, sand, gravel and chalk. The expertise required for such a task is immense and allowed us to quickly and safely adapt the tools on the cutterhead as needed.”

TBM Ursula will remain in place at the bottom of the shaft while the team at Chambers Wharf prepares to launch TBM Selina, which will create the final and easternmost section of the super sewer.

Tideway, the company delivering the tunnel, is financed by Bazalgette Tunnel Limited, which in turn is owned by a consortium of investors. The cost will be spread across water bills.