The big breakthrough: Amanda emerges on other side after epic tunnel under the River Thames

big projects events in your area

  • Tunnel Boring Machine (TBM) Amanda completes epic tunnel drive under the River Thames
  • The tunnel will house a new gas main running under the River Thames
  • Cadent’s £17.5m flagship project will help ensure London remains one of the world’s leading cities
A Tunnel Boring Machine (TBM) named Amanda has completed London’s newest tunnel under the Thames after a lightning drive under the river.
The new tunnel is 330m long with a diameter of 1.8m and has two 30m tunnel shafts, one in the grounds of the Royal Hospital Chelsea and the other in the grounds of Battersea Park.
Tunnelling has taken 24 days to complete with TBM Amanda being controlled remotely by an above ground operator who is supported by an array of engineers, technicians and specialists.
Around 4,500 m3 of material has been excavated from the tunnel and shafts – approximately the same size as 30 double decker buses.
The project team will now start preparing the tunnel for the installation of the new gas pipe which will help keep the burgeoning area – which includes the Battersea Power Station and Nine Elms development – connected to safe and reliable gas supplies for cooking and heating.
Meanwhile TBM Amanda, who was named after Royal Hospital Chelsea Infirmary Business Manager Amanda Lord, has now been removed from the tunnel and cleaned up ready for other tunnelling projects.
Project Manager Andrew Hejdner said: “The end of tunnelling marks another major landmark for the team and our focus will now shift to installing the new gas pipe.
“We’ve got some tremendous expertise on-board this project and our progress to date is testament to that.”
He added: “The tunnel is a key part of Cadent’s essential £1billion programme to replace ageing gas infrastructure in the capital.
“Our work help ensure London continues to have the infrastructure it needs to thrive as one of the world’s leading cities.”
The project is being delivered by Cadent’s strategic partner tRIIO, which also includes contractors Skanska, Barhale and designers Mott MacDonald. The tunnel is part of Cadent’s £1billion investment in replacing ageing gas mains across the capital.
For more information on the project call 0800 389 8261 or, for 24-hour operational enquiries please call 0800 096 5678.


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