12.04.17
Tunnel boring starts to extend Northern Line to Battersea
Tunnelling work to extend the Northern Line to Battersea started today as the first of two boring machines began its 3.2km tunnelling journey to lengthen the line between Kennington to Battersea.
The two machines, called Helen and Amy, were lowered 20 metres below ground in Battersea back in February, and Helen has started her work moving underneath south London to create the first new tunnel that will extend the Charing Cross branch of the Northern Line from Kennington to Battersea Power Station via Nine Elms.
Amy will start her work in a month’s time. The extension is predicted to be completed in 2020 and is the first major tube line extension since the Jubilee Line in the late 1990s.
As the two machines slowly bore underneath the capital, around 20,000 precast concrete segments will be put in place to form rings to line and support the tunnels. Then, a conveyor system will take spoil from the worksite to barges on the River Thames. The spoil will then be transported to Goshems Farm in East Tilbury, Essex, where it will be used for agricultural purposes.
Around 300,000 tonnes of earth will be excavated by Helen and Amy, who are capable of moving up to 30 metres a day, being operated by around 50 workers.
Tunnelling tradition dictates that boring machines can’t start work until they are named. After a vote by London school children, the machines were named after the first British woman to go to space, Helen Sharman, and British aviation pioneer Amy Johnson, the first female pilot to fly solo from Britain to Australia.
Last year, RTM reported that the project was at high risk of being delayed, although today’s news indicates works are currently on track to be completed on time, as it was actually ahead of schedule back in January.
Top Image: Ian Simpson Architects
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