Major breakthrough for Northern Line Extension as tunnelling machines reach final destination
- The project’s two tunnel boring machines have now both broken through at Kennington
- Their journey from Battersea Power Station to Kennington via Nine Elms, to extend the Charing Cross branch of the Northern line, is now complete
The Northern Line Extension reached a major milestone today as a huge tunnel boring machine broke through below ground in Kennington, south London, completing its tunnelling journey.
Since their launch in the spring, Helen and sister tunnelling machine Amy have been working around the clock to create the 3.2km long Northern Line Extension north and southbound tunnels that will extend the line from Kennington to Battersea Power Station via Nine Elms. Following today’s breakthrough, tunnelling on the Northern Line Extension is now complete.
The extension, targeted for completion in 2020, is the first major Tube line extension since the Jubilee line in the late 1990s.
Mike Brown, TfL 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, as well as 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 Northern Line Extension will add vital new capacity to the Capital’s transport network, bringing Battersea and surrounding areas to within 15 minutes of the City and 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 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.”
As part of the tunnelling drive, nearly 20,000 precast concrete segments were put in place to form rings to line the tunnels. A conveyor system took more than 300,000 tonnes of earth, excavated by the tunnel boring machines and equivalent to the weight of the Empire State Building, to barges on the River Thames where it was transported to Goshems Farm in East Tilbury, Essex. Here, it has been used to create arable farmland.
The cutter head of both machines will be lifted by crane out of the Kennington shafts 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. Services on the Northern line continued uninterrupted while two caverns around sections of tunnel at Kennington were excavated. A combination of hand digging and mechanical tools were used to create two junctions that were lined with iron rings and which will link the extension to the existing Northern line.