London Underground’s Northern Line Extension has reached a major milestone with the completion by JV Ferrovial Agroman/Laing O’Rourke of tunnelling works. With TBM, Amy, braking through at Kennington, the two 3.2km, 5.2m i.d. tunnels from Battersea Power Station, via Nine Elms, have now been built.
Since their launch in the spring, Helen and sister tunnelling machine Amy, the two 6m diameter NFM TBMs, have been working around the clock to create the north and southbound tunnels that will extend the Charing Cross branch of the Northern line.
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David Darcy, project director for the Ferrovial Agroman Laing O’Rourke joint venture, said, “This break-through is a major milestone in the complex engineering project to extend London’s Underground network to new parts of the Capital. The integrated Ferrovial Agroman Laing O’Rourke team is delighted to have reached this programme landmark and has taken another important step towards successful delivery of the Northern Line Extension.”
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.”
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 from the Capital’s roads. The earth has been used to create arable farmland.
The cutter head 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.
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.