Behind the scenes at the Northern Line Extension

Published: Friday 4th August 17

Here’s a peek at work going on in Battersea to extend the Northern Line – including the giant boring machines drilling their way up to Kennington.

Leader of Wandsworth Council Ravi Govindia (right) visits one of the new shafts

In April work started boring the tunnel from Battersea, and since then the two giant boring machines, Helen and Amy, have made significant progress in their 3.2m journey to join the existing Northern Line, and are currently somewhere underneath Nine Elms. 

The Battersea construction site is near the Power Station

In an incredible feat of engineering, as the machines progress along the route digging the tunnel, the precast concrete segments that line the tunnel are put in place, and the material removed is taken out of the tunnel on a conveyor belt. It’s then taken away by barge where it’s used to create arable farmland – which means bits of Battersea now form part of Essex. 

One of the giant boring machines

Two new tube stations are being built – Nine Elms station in Pascal Street and Battersea Power Station on Battersea Park Road next to the Power Station development. These will serve new developments such as the US Embassy, the Power Station and the redevelopment of New Covent Garden Market, as well as existing communities.

The Northern Line Extension helped to kick start the regeneration of Nine Elms and Vauxhall which is on course to create around 25,000 new jobs and more than 20,000 new homes.

The giant concrete segments that will  line the tunnel wait to be fitted

Wandsworth Council leader Ravi Govindia was taken on a tour of the site to check on progress. He walked inside the tunnel at Battersea to see one of the tunnel boring machines in action and went down one of the huge shafts being created in Kennington.

Underground at Kennington. Trains can be heard running through the existing tunnel on the left

He said: “This was an amazing experience – seeing this new tube tunnel actually being created in front of my eyes was a spectacular sight.

How the tube map will be re-drawn

“It really was fascinating to gain an insight into the hard work involved and to speak to some of the highly skilled engineers and other staff who are making this happen, and it was reassuring to see that the team is dedicated to building these tunnels, shafts and stations as quickly, cleanly and safely as possible.”

Tunneling is expected to be completed this year, and the stations will be completed and fitted out by 2019. Passengers should be able to ride the Northern Line to Battersea in 2020.

Get regular updates on progress of the Northern Line Extension from Transport for London

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Recent comments

More of a question in that I cannot imagine how the capacity on the Northern Line can be expanded to cope with what will surely be an enormous increase in the number of passengers during the rush hours. The current service is amazing. How many more trains can be introduced into service to cope?
Valerie Davies

18 October 2017

There is a notice on the fence bordering the new station at Nine Elms (along Wandsworth Road) that there will be direct access to Heathrow and Gatwick airports when this station is complete. However this article does not give such indication. Can I conclude that this information is misleading or al I missing something?

7 August 2017

I completely agree with others questioning why underground has not been extended to Clapham Junction, especially when politicians claim to be environmentally friendly. Given how many use CJ station and how many live in Battersea.
John Jewhurst

5 August 2017

Very interested in receiving update reports
Kevin Burke

5 August 2017

I have never understood why this extension wasn't extended to Clapham Junction. It seems bizarre. Think of the pressure it would relieve on Waterloo main line station.The reduction in journey times for those travelling from South West London & Surrey. Crossrail 2 is years away - if it ever gets built so the Northern Line at Clapham Junction would be a boon whilst we are waiting....
Peter Barnshaw

5 August 2017

From your map it looks as if Battersea Power Station is within walking distance of Clapham Junction. It is not and there is still no underground provision anywhere near Wandsworth. Can the next extension be from Battersea to Clapham Junction to Wandsworth Town and on to Putney with a possible offshoot under or over The Thames to either Parsons Green or Fulham Broadway please?
Peter Rudland

5 August 2017

What a colossal shame. Have just seen phase 1 of the PowerStation redevelopment. Shows how completely crass the Borough's planners are. Howcould they have passed the buildings that crowd out the Power Station and are even higher than it. It will hardly be seen!!!!!!! What is the point of keeping it if it is obscured .... and even more than the Council has wantonly dropped half the affordable housing. It is a disgrace.

4 August 2017

THis is really interesting, thanks for this, I will use one or two of the images for teaching civil engineering if that is OK? Do I have permission to do this?
Tom Frank

4 August 2017