Transport for London (TfL) has announced that the giant boring machines have been lowered 20m underground in Battersea and are ready start the Northern Line extension in the UK capital.

Tunnelling works are expected to start in March and will take six months to complete.

Discover B2B Marketing That Performs

Combine business intelligence and editorial excellence to reach engaged professionals across 36 leading media platforms.

Find out more

As part of this work, a huge 750t crane was used to lift the two 6m-diameter tunnel boring machines (TBMs) called Helen and Amy in London's Battersea Power Station.

The machines have been named in honour of the first British astronaut in space, Helen Sharman, and aviation pioneer Amy Johnson, who was the first female pilot to fly solo from Britain to Australia.

The TBMs are set to create two 3.2km underground tunnels to extend the Charing Cross branch of the Northern line from Kennington to Battersea Power Station through Nine Elms Station.

Both tunnelling machines will now be assembled within two 77m-long launch tunnels, before they start their journeys towards Kennington next month.

GlobalData Strategic Intelligence

US Tariffs are shifting - will you react or anticipate?

Don’t let policy changes catch you off guard. Stay proactive with real-time data and expert analysis.

By GlobalData

The TBMs Helen and Amy will each be 100m in length once complete.

"The TBMs are set to create two 3.2km underground tunnels to extend the Charing Cross branch of the Northern line from Kennington to Battersea Power Station."

After completing construction of both TBMs and their gantries, a conveyor system will be built to take the spoil from the tunnels up to barges on the River Thames.

Helen and Amy will excavate more than 300,000t of earth before the spoil is taken to Goshems Farm in East Tilbury, Essex, by boat.

The Ferrovial Agroman/ Laing O’Rourke (FLO) joint venture unveiled the two TBMs at a ceremony in Battersea last month.

The Northern Line extension is targeted for completion in 2020.


Image: Lowering of the tunnel boring machines. Photo: © John Zammit.

Railway Technology Excellence Awards - Nominations Closed

Nominations are now closed for the Railway Technology Excellence Awards. A big thanks to all the organisations that entered – your response has been outstanding, showcasing exceptional innovation, leadership, and impact across the defence sector.

Excellence in Action
Omnevo’s digital Order-to-Seat platform has won the Innovation Award for Onboard Retail, redefining how passengers order, pay, and receive F&B at their seats. Learn how this solution is cutting waste, streamlining logistics, and enabling operators to personalize and modernize onboard retail.

Discover the Impact