Breakthrough in tunnelling for Northern Line extension

Two more stops on the Northern Line moved a step closer yesterday with the completion of tunnelling.

The extension to Nine Elms and Battersea Park reached a major milestone when the boring machine Amy broke through into the subsurface works area at Kennington. She joined sister machine Helen so that both the 3.2km tunnels required for the project are finished.

Since their launch in the spring, Helen and Amy have been working around the clock to create the north and southbound tunnels that will extend the Charing Cross branch of the Northern line.

The extension, targeted for completion in 2020, is the first major extension to a Tube line since the Jubilee line in the late 1990s.

It will add vital new capacity to the Capital’s transport network, bringing Battersea and surrounding areas to within 15 minutes of the City and the West End. It will also enable the regeneration of the Vauxhall, Nine Elms and Battersea areas, spurring economic growth by supporting around 25,000 new jobs and more than 20,000 new homes. In addition, the construction of the extension is boosting the UK economy and supporting around 1,000 jobs, including around 50 apprenticeships.

The Mayor of London, Sadiq Khan, said: “This breakthrough is a momentous moment for a project that is going to bring huge benefits to south London. The Northern Line Extension is not only going to make travelling to Battersea and Nine Elms easier, it’s also going to bring tens of thousands of new jobs and homes to the area. It’s another great example of why new infrastructure is so vital to London’s success and the wider economy.”

Mike Brown MVO, London’s Transport Commissioner, said: “I’m delighted to welcome the two tunnelling machines to Kennington after their epic journey. Both machines have had to navigate a challenging, congested path under south London which included sewers, power cables, a Victorian-era well, and existing Victoria and Northern line tunnels. This achievement brings us a significant step closer to the delivery of the first major Tube extension in nearly two decades.”

The Chief Secretary to the Treasury, Liz Truss said: “It’s very exciting to see this new phase of the Northern Line delivered. Great infrastructure, including the Tube, is vital to a thriving London. That is why we backed this important project which is supporting thousands of jobs and new homes in our capital.‎ And that is why we are backing projects across the country that will help drive enterprise and growth.”

Rob Tincknell, Chief Executive Officer at Battersea Power Station said: “This is a really significant milestone in the regeneration of both Battersea Power Station and Nine Elms and reconfirms certainty about the two new stations. That such a vast extension to the London Underground network is being funded through the regeneration taking place throughout Nine Elms is a credit to all those involved in nurturing this project throughout the years and a powerful example of how new transport infrastructure can be delivered by the public and private sector working successfully together.”

The leader of Wandsworth Council, Ravi Govindia, said: “Today’s event is a real milestone in London’s first new Tube line extension for almost 20 years. This is an extremely important project, not just for the borough but the whole Capital, and Wandsworth has put in a lot of time and effort to shape the unique funding package that has taken us to where we are today.

“Working with the private sector we are now seeing our hard work come to fruition and the tunnelling machine breaking ground is a tangible reminder that the Tube extension will soon be a reality, transforming the fortunes of north Battersea and making the Nine Elms regeneration programme one of the greatest sources of new jobs and homes in the country.”

A conveyor system was used to take more than 300,000 tonnes of excavated earth to barges on the River Thames where it was transported to Goshems Farm in East Tilbury, Essex, saving thousands of lorry journeys on the Capital’s roads. The earth has been used to create arable farmland.

The cutter heads of both machines will now be lifted by crane out of the shafts at Kennington while the rest of the machines will travel back to Battersea and be lifted, in parts, out of the ground there.

Work on the new stations at Battersea and Nine Elms is progressing well and services on the Northern line have continued uninterrupted while the work has taken place.