TfL have released a number of images showing the Tunnel Boring Machines (TBMs) for the Northern Line Extension. These were lifted into place at Ferrovial Agroman Laing O’Rourke’s TBM portal at Battersea earlier this month.

The images highlight that whilst this will be a different build (both in terms of scale and, to a certain extent, technique) to Crossrail, the overall approach and technology involved are broadly the same. Despite coming from a different supplier (NFM Technologies in France) for example, the TBMs themselves are strikingly similar to those built by Herrenknecht.

As is traditional, the two TBMs required for the Northern Line Extension, like the Crossrail ones, also bear female names. The first, Helen, is named for astronaut Helen Sharman. The second, Amy, is named for British aviation pioneer and WW2 pilot Amy Johnson. Indeed this is not Johnson’s only link to transport in London – the Hilton hotels at both Heathrow and Gatwick are named in her honour.

With both TBM heads now in place, their associated trains will be assembled and attached. The 2.5km dig will then begin in the summer and finish in early 2018. Again, as on Crossrail, the spoil will be removed by river – also to Essex where this time it will be used to create arable land.

A wider view of the portal site

Lifting in front of Battersea Power station

The lift in progress

From below during the lift

Heading beneath the surface

The associated TBM trains will be built and attached beneath ground

A side on view of the TBM head. Note the shallow depth in comparison to the Crossrail portal at Pudding Mill Lane

Beneath ground and in position.

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There are 112 comments on this article
  1. Snowy says:

    The cranes look rather similar to those that have just completed the Ordsall Chord bridge lift today, glad to see the rail industry keeping them busy!

  2. Littlejohn says:

    Pedant alert. In the first line – surely ‘TfL has’ not TfL have’?

  3. Littlejohn says:

    ‘ …. the two TBMs required for the Northern Line Extension also bear female names’. I have the impression that TBMs traditionally always have female names. Am I wrong?

    [I have slightly reworded the article to reflect this. PoP]

  4. Anonymous says:

    Great, more tube capacity for an area already extremely well served by the tube. But hey, rich people.

  5. gerry says:

    Anonymous: Re yours of 21st Feb – Battersea is not served at all by the tube – the only tube lines in the area are the Northern and Victoria – neither of which serve Battersea.

  6. @Littlejohn

    “surely ‘TfL has’ not TfL have’?”

    The TfL Editorial Style Guide is silent on the issue. I’m flummoxed. Suggestions?

  7. ngh says:

    It is worth noting that the spoil from the station box also went out by barge to Essex via the conveyor system seen in the background of the first 2 photos to barges moored up at the old coal barge unloading jetty. The spoil from many CR stations went out by road at least initially by contrast.

    Re Snowy,

    Similar but smaller (and a lot less counter weight) than those up north! The crane hire firm also did lots for Crossrail which is unsurprising given that they are the largest crawler crane supplier in the UK.

  8. John Bull says:

    Like football teams, organisations are plural as far as the LR style guide is concerned.

  9. Purley Dweller says:

    Yet often football teams are referred to in the singular on TV and it really jars with me.

  10. Melvyn says:

    @ Anonymous NLE is being privately funded by developers and it’s up to other towns and cities to attract private funding if they want similar upgrades on same basis .

    I wonder if Spurs is singular or plural?

  11. Peckham Ponderer says:

    “Spurs ARE on their way to Wembley”. Possibly…

  12. Taz says:

    For a six month drive couldn’t they have used just one TBM, bringing it back for the second drive? They are to be retrieved fromthe Kennington shafts.

  13. JohnM says:

    In terms of Amy Johnson there was another pair of transport links – she flew from Croydon Airport which was the destination shown on buses long after the airport closed. Also Waddon Station on the West Croydon Sutton line was known as Waddon for Croydon Airport in the 1930’s.

    In terms of female names for TBMs most machinery such as ships were described as female at one time but now are addressed as ‘it’ . Always grinds with me

  14. ngh says:

    Re Taz,

    Probably if there hadn’t been delays for other reasons they could have used /reused 1 but they are now under time pressure with some of the initial flats complete.

    Also worth mentioning on the spoil front that a second set of spoil extraction conveyors and jetty will also be used for the Thames Tideway tunnel spoil extraction with another pair of TBMs launching soon within 200m of the Northern line pair.

  15. Alan Burkitt-Gray says:

    An editor (and pedant) notes: Most business publications, including the Financial Times and the Economist, and virtually all business magazines I can think of (including those I’ve worked for), specify that companies and similar organisations are singular.

    The BBC is looking for a new Doctor for Doctor Who.
    Unilever has rejected a takeover bid.
    TfL is thinking of extending the Bakerloo line.

    The two exceptions are sports teams:
    Arsenal is looking for a new manager.
    England (the team, not the country) are losing the test match.

    and the police:
    Thames Valley police have issued a description of the person they want to interview.

    even the Government is usually singular.

  16. Alan Burkitt-Gray says:

    and, just to prove how difficult it is, i meant to write “Arsenal are looking for a new manager.” Are they? I don’t know.

  17. timbeau says:

    The station box for Nine Elms is now very clearly taking shape as seen from trains on the SWML.

  18. timbeau says:

    “Great, more tube capacity for an area already extremely well served by the tube”
    On the contrary, Battersea Park is about as far from a Tube station as you can get in central London – although it is well served by National rail stations.

  19. Moosealot says:

    Point of pedantry:

    Again, as on Crossrail, the spoil will be removed by river – this time to Essex…

    While the spoil may be headed to a different destination to the Crossrail spoil, both destinations are in Essex.

    [Reworded more appropriately. PoP]

  20. Walthamstow Writer says:

    @ Melvyn – in theory the line is privately funded but it isn’t really. The main funding is a Public Loans Board loan, given government backing, that has to be repaid. The key repayment mechanism is a rake off from future Council Tax / Business Rates levied in the area. Furthermore I understand the “opportunity area” also has special tax treatment from government (checks – yes there is a 25 year Enterprise Zone). I think there was to have been a contribution from the Malaysian developer of Battersea Power Station (BPS) but it in no way funds the entire cost. It’s possible this has been removed and replaced by the new funding mechanism. It’s not in the public domain as to what happens if the scale of development in the area is not as expected and there is not the extra rates income channeled via the local authorities to pay back the loan. I assume someone (government?) carries that repayment risk until such time as money can be raked off from the private sector. I dare say it will be lovely if the site does well and money flows but there are no guarantees given all the normal influences that apply in a national economy plus added complications like Brexit. Development in this area and take up of new opportunities will be highly influenced by “market sentiment”.

    It is also worth bearing in mind that the developer has redesigned the proposed over station development at BPS Station which has forced a redesign of the station and a delay to the project. Of course everyone is merrily glazing over this rather poor state of affairs given TfL / LU are locked into an extremely tight timescale for delivery of the new link. The commercial ramifications are also not in the public domain.

  21. Graham H says:

    @LBM/Littlejohn/Alan B-G – let Gowers’ Complete Plain Words be your guide. TfL could correctly be either plural or singular; there is no rule. Gowers adds: “The plural is more suitable when the emphasis is on the individual members, and the singular when it is on the body as a whole.”

    More generally, it’s good to see tangible evidence at last of NLE but, as ever, one can’t help but wonder whether, in a rationally planned system, this would have been a priority…

  22. NickBxn says:

    Much as it is to be welcomed, it is as rationally planned as the rest of south London’s railways, so not much change there, then.

  23. Giovanni says:

    What dug the tunnels into which these TBMs will continue the job? And what will happen to these and the Crossrail TBMs?

  24. shamonthedon says:

    Has a decision been made about the further extension to Clapham that has been mooted. Would seem daft that now the TBM are in place..fuller use can’t be made of them

  25. Herned says:

    TBMs cost in the order of £10m or so, certainly the Crossrail ones did… while this is a lot of money for the average person, it’s a trivial amount once you get into billion-pound projects, so devising new tunnelling in order to reuse a TBM is never going to happen

  26. John Bull says:

    While the spoil may be headed to a different destination to the Crossrail spoil, both destinations are in Essex.

    Good point! East Tilbury I think. I’m going to try and get down there like I did to Wallasea.

    What dug the tunnels into which these TBMs will continue the job? And what will happen to these and the Crossrail TBMs?

    You dig the first 70m or so by hand, which then gives you room to lower in the cutting head and build the associated train (Which is the bit that lays the tunnel lining as it advances). Then the TBM does the rest.

    As others have said, there’s not really any value (in real terms) in the TBMs once they’ve done their job. By that point they need an awful lot of reconditioning to be useful and, at £10m or so a pop, that’s just not really good value for money.

    I’ve not seen the NLE contracts, but I’d assume they’re broadly the same as the Crossrail ones with Herrenknecht. There, the TBMs that could be easily removed were sent back to Herrenknecht who then have the choice of reconditioning them and selling them as second hand to more cash-strapped infrastructure projects that don’t mind accepting the additional risk of failure, or (more likely) break them down and keep the usable bits for reconditioned spare parts for other TBMs they’ve got out in the world.

  27. Graham H says:

    @Herned -nevertheless, there was, and maybe still is, an active market is secondhand TBMs. Not quite, as my tunneller colleagues used to joke, to the point where you’d be approached by a guy in a Peckham pub – “Do you want a nice used TBM? Got a couple in the van out the back…” -but close to.

  28. John Bull says:

    Oh aye – they’re the reconditioned ex-business laptops of the infrastructure world. Give it a year or so and I fully intend to do a “where are the Crossrail TBMs now?” piece.

  29. As the risk of repeating a lot of comments that have been made previously in other articles:

    Anonymous 17:22
    But hey, rich people

    A complete misunderstanding of the situation. For starters, it is expected that as many people will use the extension in the morning to come into the Battersea/Nine Elms area for employment purposes. These will not tend to be rich people and will probably be just the sort of people that you believe public transport should be aimed at.

    Anyway, why shouldn’t rich people have good public transport if the demand is there?

    All this ignores public transport’s greater place in society and in planning for the future.


    As pointed out by Herned, the cost of TBMs is a tiny portion of the project cost. I reckon 2% maximum but probably more like 1% once they have been sold back to the supplier at the end – there will undoubtedly be a clause in the contract for this.

    Also you don’t want to just reuse a TBM straightaway. You really, really don’t want them to break down for all sorts of reasons. So you would have to factor in a major maintenance period between the two bores which would add to the delay.

    Boring the tunnels is relatively trivial. The article says it should be finished early in 2018 but doesn’t really make it clear we are probably talking first week in January. What takes time these days is post-tunnelling activity including fitting out and two years have been allowed for this which is probably not excessive given some of the station and ventilation work involved.

    The developers probably want to see the spoil route to the river removed at the earliest opportunity. Note also ngh’s comment about need to fit in with Thames Tideway.


    well served by Network Rail stations by today’s standards but these have virtually no opportunity for expansion/more frequent service to cater for the expected footfall in future.


    Much as it is to be welcomed, it is as rationally planned as the rest of south London’s railways, so not much change there, then

    Err? In what way is this true? It might be the case that it wasn’t originally intended by the transport planners but the site was seen as a major opportunity area that needed good public transport and a lot of options were looked at.

    You can argue that the Northern line extension was pushed for by the developers but equally you could argue that the planners would have almost certainly come to the same conclusion anyway and pushed ahead. Once Cross River Tram was abandoned and the ability to tack onto that scheme was a non-starter there really weren’t many other options. What viable alternative would you suggest?

    Walthamstow Writer,

    My understanding is that some of the covering of the cost relies on fare revenue – not good then if you have a Mayor who believes in freezing fares. I have heard no suggestion that the cost of the trains will be covered.

  30. timbeau says:

    @John Bull

    “You dig the first 70m or so by hand”
    Not literally, I assume? There seem to be a lot of JCBs* around the site

    *other brands of construction equipment are available

  31. One thing the article doesn’t cover (because it wasn’t what it was about) is that the step-plate junctions at the Kennington loop end are remarkably advanced and these, too, are expected to be complete by around the end of this year with a Christmas closure of the Kennington loop (with, hopefully, minimal disruption to passengers) to complete the job.

    So a combination of an early start on the step-plate junction, use of TBM’s and use of spray concrete lining (SCL) for the parts TBM’s can’t reach means that the construction of the tunnels is very fast. It’s the other bits that take the time.

  32. Graham H 23:37,

    As is often the case, a short enlightening comment from you makes sense out of a confused situation.

    I will regard other style guides as for guidance only.

    Certainly I can’t bring myself to write “TfL are an organisation” or Arsenal are a football club” other than to show how awful it reads.

  33. timbeau,

    In fact to dig by hand at all in such circumstances would normally be a major Health and Safety breach – though Crossrail had to do it when excavating behind the existing platforms at Tottenham Court Road.

    One of the beauties of Sprayed Concrete Lining is that the operator is nowhere near the “coal face”. He is playing with his glorified X-box from a safe location.

  34. timbeau says:

    Are TBMs built to a standard size, or are these special Tube sized ones? – which would reduce their secondhand value considerably.

    Comments about lost opportunities above – there were plans at one time to extend the Northern line southwards from Kennington towards Streatham – this would not now seem to be possible

  35. John Bull says:

    One of the beauties of Sprayed Concrete Lining is that the operator is nowhere near the “coal face”. He is playing with his glorified X-box from a safe location.

    Almost literally in some cases – I’ve noticed at a few trade shows that some of the spraycrete rigs actually use a modified Xbox 360 controller.

    I’ve always wondered if any of them went the full hog and integrated it with Xbox Achievements.

    Leading to something like this popping up on your monitor.

  36. Pedantic of Purley says:


    Practically all TBMs are bespoke. This applies not only to size but other issues such as appropriateness for the type of ground expected to be encountered. Crossrail had two different types of TBM for different conditions.

    A major consideration with tube extensions is that you don’t want a big extension if the line involved is almost at capacity anyway. There is probably a practical limit to how much you can increase a line’s capacity.

    Bearing the above in mind, any extension to the Charing Cross branch of the Northern line would have needed to be limited to one or two stations. From that point of view it is hard to see what eventual destination could possibly be more suitable than Battersea Power Station and those suggested in the 1980s would be totally inappropriate today.

  37. Andrew M says:

    Echoing Timbeau’s comment, are these tunnels going to be the same diameter as the existing Northern line tubes, or will they be wider?

  38. Giovanni says:

    I found this article quite helpful on this topic, for those who haven’t seen it:

  39. ngh says:

    Re timbeau,

    New machines are custom sized for the job as is the cutting head design for local geology and pressurisation system if needed.
    Lots of the bit behind and inside e.g. motors, gearbox, hydraulics, conveyors, robotic tunnel segment handlers and control room are standardised* so get reused post refurbishment.

    * some bits will be standardised by size e.g. id the TBM from the small /medium / large family of machines from that manufacturer.

    Digging out. Almost certainly not with JCB as there is equipment far more suited especially robotically controlled.
    The station box is initially created by concrete piling then dug out with conventional excavators then basedo on local geology several metres of tunnel are dug out then sprayed relatively quickly (even in the best London geology (clay) a few hours at most), then the next few metres is dug then sprayed.

  40. John Bull says:

    A major consideration with tube extensions is that you don’t want a big extension if the line involved is almost at capacity anyway.

    Hence why I laugh / cry at the bursts of “let’s extend the Victoria line to Chingford!” crayoning that occasionally erupt from various political and news groups up Walthamstow way.

    In capacity terms, extending Tube lines is now – with the exception of the Bakerloo – effectively a zero-sum game. Sure you can do it, but (in the case of the Vic) you then have to be the guy who explains to everyone at Seven Sisters why they can no longer get on a train.

    Frankly we should really do a Buzzfeed-esque “why your Tube line will never be extended” piece some day.

  41. GC82 says:

    I remember it being discussed that Queenstown Road might close once this extension is open. Is this likely to happen? I have not heard anything official?

  42. ngh says:

    Re Andrew M,

    No much larger than the rest of the original deep tube tunnels to accommodate a walkway and better ventilation / aerodymanics etc.
    The existing cast iron tunnels are 3.56m I.D. and the new tunnels 5.2m I.D. with a 6.1m TBM diameter (Compared with the 4.75m I.D. / 5.8m TBM diameter in the tunnel talk article based on the public inquiry info)

  43. Anon E. Mouse says:

    @John Bull
    That Manic Miner achievement gave me a good laugh. As such, I’m very curious about where you got that from, or did you make it yourself?

  44. timbeau says:

    I’ve not heard that – it would be highly inconvenient for anyone travelling to Queenstown Road from Putney/Richmond etc (and quite a lot of US embassy staff, for example, might want to live out that way). They would either have to go all the way into Waterloo, and out again on the Northern Line, or alternatively change at Clapham Junction for Battersea Park (or for the Northern Line if it ever gets extended there, in which case you might just be able to dispense with Battersea Park as well) or

  45. ngh says:

    Re Timbeau /GC82,

    Give what they have spent and are planning to spend on Queenstown Road probably not…

  46. Walthamstow Writer says:

    @ JB – I particularly like the strident local demands to extend the Victoria Line to connect with the Central Line at Leytonstone / Woodford. As you say the bit everyone misses is the fact that it’s not the early 1980s anymore when the public transport system was far, far less stressed than it is now. There was capacity waiting to be filled up meaning crayons could go mad proposing all sorts of extensions and the extra demand could be absorbed. Not really possible now.

  47. Andrew M says:

    Thanks. The TBMs are 6.1m wide, but the tunnels internal diameter is only 5.2m; does that mean there’s 90cm of lining?

  48. Stuart says:

    Are the cutting surfaces black because it is the colour of the Northern line ?

  49. Pedantic of Purley says:

    Andrew M,

    If we are talking about the diameter then it has lining at each end. So a maximum of 450mm. Allow for the fit not to be too tight and your are probably talking 400-440mm which seems about right to me for a tunnel of this size.

  50. Tunnel Designer says:


    The segments have to fit inside the TBM can, which will ideally be a little smaller than the TBM cutting head (but not too much). Look at the 3rd from last picture (shows the rear end of the TBM), the large yellow bit of kit is the erector that will pick up the segments and assembled the ring inside the can. That sets the limit on the maximum ring outside diameter, or in reality that space is sized based on the lining thickness the designer calculates.

    On that basis the segments will be at most 300mm thick, maybe less if they are pushing the concrete tech. 400mm would be very over designed for a tunnel that size, at the proposed depths.

  51. Pedantic of Purley says:

    Tunnel designer,

    I bow to your better knowledge. I was working on the basis of thinking that concrete segments were around 300mm on the Victoria line and would have to be slightly thicker for the larger diameter tunnel.

  52. timbeau says:

    Does it follow that the rings have to be thicker for a larger diameter (less sharply curved) tunnel?

    “Give what they have spent and are planning to spend on Queenstown Road ”
    I’m intrigued. It certainly looks very run down at track level.

  53. ngh says:

    Re Timbeau /PoP,

    “Does it follow that the rings have to be thicker for a larger diameter (less sharply curved) tunnel? ”

    It depends on number of criteria but actually the the opposite can be true down to a minimum thickness for a material and segment size/geometry as a smaller diameter and therefore greater curvature can actually need thicker walls. See previous LR dicsussion on Bakerloo or Northern tunnel wall thickness issues near Charing Cross under the Thames.

  54. ngh says:

    Re Timbeau,

    Queenstown Road platform extensions, new points to the west recently and bring the disused platform back into use at some point in the future.

  55. NickBxn says:

    @PoP 10:34 -I was having a gentle dig at how portions of the network don’t quite join up due to varied priorities at different times – as manifest by subsequent comments on lack of connectivity via other near-by stations that are just a bit too distant from the new ones to be viable interchanges. I understand that ever-changing circumstances can render long term strategic joined-up network planning as useful as getting the deluxe colouring set box out, which makes us lucky that the Crossrails are getting anywhere.

  56. Melvyn says:

    What a pity at least 1 of these TBMs when it reached Kennington couldn’t keep going south to help remove those Clapham stations with narrow island platform like Angel and Euston used to have …

  57. marek says:

    Well they will of course be heading north as they reach Kennington, so it will be hard for them to keep going south. Other than that, no reason at all why not.

  58. Taz says:

    @ Melvyn – Of course it could be launched from a new shaft, but would save maybe 1% of costs, per above. Would need a shaft at each end, two step plate junctions, two new platform tunnels, planning, materials, fit-out etc. So really a stand-alone project which doesn’t seem to have high priority currently.

  59. Dave says:

    I’m curious to know the editorial policy on including “latest in TfL news” articles like this. Why cover the TBMs but barely mention (say) the new ticket halls at TCR and Victoria?

  60. John Bull says:

    I’m curious to know the editorial policy on including “latest in TfL news” articles like this. Why cover the TBMs but barely mention (say) the new ticket halls at TCR and Victoria?

    Our editorial policy on what gets written is, effectively:

    1) Do we think it is interesting?
    2) Does one of us have sufficient knowledge of the topic or the desire to learn about it?
    3) Does that person realistically have the time?
    4) Has it been covered in depth elsewhere?

    Those last two are the deciders in a lot of cases.

    Ultimately we’re a small group of volunteers writing for fun and our overall ethos is that we’d much rather write less frequently but thoroughly on topics than try and be a “news” site. There are plenty of other places out there that do that already with more people who get paid to do it.

    Similarly if we’re going to do something that isn’t fun for us or means extra time then we’d rather it be something others definitely aren’t covering well enough – such as a GLA committee or TfL papers of some kind.

    Victoria would have got covered, for example, if one of us had time to go when it was opening and then also had the time to write it up. But we didn’t (and I also thought Ianvisits covered it well anyway).


    Well, as long time readers will probably have noticed – I have something of a soft spot for TBMs and the logistics of how they work.


  61. Pedantic of Purley says:


    lack of connectivity via other near-by stations that are just a bit too distant from the new ones to be viable interchanges.

    Still a bit confused. Are we talking about Vauxhall? Technically very difficult and in any case a decision was made not to interchange at Vauxhall because you don’t want even more traffic funnelling onto the Victoria line. Or Battersea Park/Battersea Power Station? The former is high up, with awkward access and no opportunity for stopping more through trains there. Besides to get closer you need to tunnel further which means dealing with the piles under the Dogs and Cats Home. In any case it could be argued that transport should be subservient to development requirements and not unconditionally determine the nature of the development.

  62. Anonymous says:

    I too dislike how the route for this extension has been chosen.

    Usually when an extension to a piece of rail infrastructure is planned, the route and the locations it will serve are planned in meticulous detail, with exhaustive cost-benefit analysis undertaken to find the best option.

    However, in this case the developer has just chucked a big bag of cash at TfL for a “bespoke” tube extension that deliberately avoids some very useful interchange so that the prospect of empty morning tube trains can be used as a selling point. In return, Morden branch trains will likely lose what’s left of direct CHX branch trains and locations like Waterloo will become a nightmare for boarding in the morning.

  63. ngh says:

    Re Anon 0949,

    Vauxhall is already struggling to cope so there was no chance it was going there (e.g. pre BCR technical fail), the Nine Elms station is obviously designed to attempt to abstract so bus users from the Wandsworth Road corridor before they get to Vauxhall.

    If you are worried about getting on at Waterloo in the morning maybe campaigning to get TfL to sign of on the proposed extra Northern line trains might be an idea?

  64. Briantist (Haisen-tetsu) says:

    @John Bull

    Perhaps there could be a once-a-year thread dedicated to asking the below-the-line contributors about subjects that they would like to cover, or perhaps discuss about writing full articles about.

    For example, I find it odd that the Brighton Main Line is at about article 10 and not even half-way down the line, but the actual re-connection of Stratford to Angel Road is being built and has only had one rather oblique article.

    I’m always wondering if I can contribute about the information systems (such as Darwin) that drive the customer experience systems for train and tube users in London.

    Just a thought.

  65. Walthamstow Writer says:

    @ Pop – In any case it could be argued that transport should be subservient to development requirements and not unconditionally determine the nature of the development.

    Arrrgh – bangs head on wall. I hate this sort of nonsense even if it is the current “convenient” orthodoxy because government can’t be bothered to spend public money on useful things. Surely transport is there to serve the mobility needs of the people who live / work in a place or wish to visit it? It is not *solely* about development. Sometimes that will mean serving a development area, other times it will not as it has other equally valuable functions to fulfill like reducing existing congestion or creating new network links. (Not criticising *you* just this latest nonsensical fixation with transport schemes only being justified if people lob bags of private cash so they can profit from them).

    @ Ngh – alternatively we could have had a more sensible political approach to fares and funding but that “ship has sailed” for the moment. We must wait to see what happens with the planned approval papers for extra tube rolling stock – they should be coming forward soon *unless* something has gone badly wrong with the costs from bidders not aligning with the inevitably reduced amount of capital budget. The fact that TfL have stopped publishing any meaningful project level information makes me very wary about what is going on with capital investment with the search for “efficiencies” and “fighting the (TfL) flab”.

  66. Walthamstow Writer says:

    @ Dave – some of us (preen, preen) do put our photos of new developments in the London Reconnections Group on Flickr. While that’s not the same as a full blown article there are, at least, some piccies of, say, the new link and ticket hall at Victoria. I haven’t searched out the new lifts at TCR yet but will probably do so soon if only to satisfy my own curiosity as to where they are and photos will follow – provided there aren’t too many people in the way.

  67. Southern Heights (Light Railway) says:

    @WW: only being justified if people lob bags of private cash so they can profit from them

    Well put, I’m sure the developer expects to make money on the money they’ve spent… So in effect, we’re subsidising them!

  68. Pedantic of Purley says:

    Walthamstow Writer,

    Just saying transport is a means to an end and not the end product.
    Or, to put it another way, an integrated transport policy should not just integrate with other policies within transport but also with non-transport policies.

    There is no point in transport being given absolute priority or you risk the transport infrastructure destroying the very reason that people want to visit or live in a area. There has to be compromises or you risk things like a railway at surface level over Greenwich Park (as originally proposed) or Ringway 2.

    Given that the location of Battersea Power Station is fixed, demolition is not an option and this is a scheme based around that, I find it completely understandable why the line goes where it does and that the entrances are where they are.

  69. ngh says:

    Re WW,

    At least NR have started publishing the quarterly(ish) CP5 plan updates again if you can find them on the new website, which suggests things have settled down somewhat.

    It will be interesting to see what the opposition parties do if upgrades that probably would have gone ahead now don’t so I can’t see TfL or the mayor wanting too much evidence around to be used against them.

    There isn’t likely to be too much real new news (let alone good) for London transport users in general anytime soon. (from the TfL side New Crossrail stock entering service in few months and first 710s on West Anglia but both are long expected but plenty of potential bad news on buses. But most good new news will likely be from NR/DfT/TOCs so the TfL media team will have to work hard to make what they can from their side.

  70. Southern Heights,

    in effect, we’re subsidising them!

    Maybe – you could always argue that. Even more so if they don’t make a contribution.

    What you seem to be forgetting though is that the developers are only responding to the Mayor’s plan and putting forward their proposals which not only got approved but were strongly supported. It does not make sense to have a go at the developers who are, effectively, implementing public policy. You might not agree with that policy but that is not something to blame the developers for.

    I am baffled to see what you would prefer as an alternative. Have the Battersea Power Station site remain desolate with only ad-hoc planning? Leave it unconnected to the tube system when this can be done at minimal cost to the London taxpayer?

  71. ngh says:

    Re PoP,

    It will be interesting to see how well (or not) the various Battersea developments link up at a pedestrian level if at all given the former Gasworks site is a different developer as are site east of the power station. Will walking in the area be as bad as today?

  72. ngh says:

    Re PoP (@1244)

    Previous comment was for @1234.

    Even if most of the Power station residential development properties are sold to overseas buyers at least it diverts them from buying up properties elsewhere in London. Given the number of failed attempts to redevelop the site over the last 35 years someone actually doing it is welcome. It also started the ball rolling on a number of commercial (office) developments which will increase the number of people commuting into the area too.

  73. Walthamstow Writer says:

    @ Ngh 1237 – nice to see I’m not the only one who finds the new NR website rather impenetrable. It seems to me that NR have removed a lot of stuff that, while not the most thrilling of things, was useful e.g. forward plan of possessions on the railway. The old website was far from perfect but at least it was comprehensive.

    I share your suspicion that the lack of projet info from TfL is the direct result of City Hall intervention so as to obscure what has happend to the investment programme. During the budget scrutiny sessions TfL said they had to reconstruct the budget from the “bottom up”. Val Shawcross also said that Boris’s last budget wasn’t built on very firm foundations / assumptions hence the reworking. Also priorities have changed in some areas and so has the funding. Now I can sort of half believe this but I can also see some political point scoring going on. Assembly Members were still strongly critical that they couldn’t follow through from the previous budget to the proposed one and that TfL had not supplied information that had been promised. None of this helps improve transparency despite the Mayor saying he’d run the most transparent administration ever at City Hall. The big time gap in TfL Panel meetings on project matters has also (temporarily) removed a source of information from the public domain.

  74. timbeau says:

    “There isn’t likely to be too much real new news (let alone good) for London transport users in general anytime soon. ”

    Lots of actual new developments coming up though (rather than endlessly re-announced forthcoming projects) . By the end of next year we will have not only the 345s and 710s that you mention, but the 707s on SWT and the 717s on the Northern City, not to mention the IEPs (Classes 800-802) at Kings Cross and Paddington. And the opening of the Crossrail Core, and Thameslink 2000-and-counting (from the Brighton Main Line to the Great Northern main line via the Bermondsey flyover, rebuilt London Bridge, and Canal Tunnels) should all be running.

    All scheduled to be by the end of next year.

    And perfectly timed, because (for me at least) there will be a fare cut of 100% ! (after 9:30 anyway – and only 34% off the IEPs)

  75. ngh says:

    Re WW,

    There is a gradual transfer from old to new NR website over several months so everything is still available on the old archived one (pre early Jan switch over) and is gradually being transferred over to the new one with more appearing all the time.

  76. ngh says:

    Re Timbeau,

    I did also say “But most good news will likely be from NR/DfT/TOCs” with all of what you listed and more in mind. There won’t be much good news from TfL in the first half of this year and plenty of bad with the strikes and cuts. Over the next 2 years the TfL good, DfT/NR/TOCs bad” mantra in London may shift a little. Crossrail will be thri good news story (unless some problems appear!)

    I would be very surprised if the new SW franchise announced in about 8 weeks doesn’t have lots of new stock.

  77. Melvyn says:

    Well it seems the new entrance to Victoria Station hasn’t lasted very long once it’s subjected to a bit of wind today . With part of the roof coming off and tbevstation name signs rattling in the wind . See –

  78. lmm says:

    @John Bull Is the Bakerloo really the last extension opportunity? Per previous threads That Which Must Not Be Named makes full use of its capacity and the North City Line would be hard to connect to anything, but it seems to me there are two places where significant spare capacity terminates in Zone 1 – namely Edgeware Road and Aldgate. What am I missing?

  79. Pedantic of Purley says:


    You have to look at the sub-surface lines as a whole. Actually they are brilliantly optimised to use as much of the network as possible with only short stretches in the centre not having more than 27tph. Under resignalling most the old Circle line will have 32tph with only Gloucester Road – Edgware Road being a significant length running less than that.

    I am a bit baffled by the idea of spare capacity at Aldgate. After resignalling it will have 16tph in the two central terminating platforms and 8tph on the outer and inner platforms. There is a junction at each end of the platforms and this has to fit in with the rest of the very complex network. 24tph seems a very credible use of capacity for such a location.

    After resignalling there will be 32tph between Praed St Junction and Edgware Road platforms. So no spare capacity there. There is, in principle, spare capacity between Edgware Road and Baker Street but east of Baker Street this is needed for Metropolitan trains to Aldgate.

    And forget about extending sub-surface lines. Even if technically possible the fact they are so near the surface makes it ludicrously expensive- the long term lesson learnt from building the Metropolitan line was was that cut-and-cover was not the way to do it as it was hopelessly expensive – unless you happened to have a new road that you could dig up.

  80. Toby says:

    There’s a few places where the SSL are under buildings not roads and pavements. The short section between Praed St junction and Edgware Road Station is two track for a few hundred metres, I think for about the length of the block on the south side of Praed St as it meets Edgware road. If it were possible for TfL to buy and demolish that block, four track that short section then build above it could be revenue positive. But if it were I doubt it would be left for a beginner like me to say.

  81. Graham H says:

    @Toby – how could that be significantly revenue positive?

  82. Malcolm says:

    Just a nit-picking challenge to PoP’s “forget about extending sub-surface lines”. If there was one of them “asking” to be extended, there is no reason to restrict that extension to have a significant amount of that extension at the same “impossible” level. A short 1 in 40 incline (*), then build the rest at whatever depth you like. Tunnels can be bored a suitable size to fit any chosen range of trains.

    As for Aldgate and Edgware Road, lmm’s observation was that they are points in inner London where trains terminate, and a theoretically ideal network would not have any of those – the theoretically ideal metro line has two or more well-balanced ends.

    The usual permission is granted to use this information to crayon away to your heart’s content, but obviously to publish the outcome ANYWHERE BUT HERE.

    (*) … on some handy linear site … say somewhere where a sub-surface line was once, err, broadened…

  83. rational plan says:

    There is no easy way to peal off a SSL line or extend it beyond current terminus. The difficulty of fitting in new junctions and stations would mean you might as well look at building new lines any way. Of course there have been proposals in the past such a the District line express from Earls court to the City (which died off sometime pre war, I think).

    If you really needed more capacity off the Metropolitan then a new line from the Baker street to the City would be the answer (only stopping at major stations). It would allow a big increase on the Hammersmith and City line. etc etc

    Where you would send it after Aldgate (if you must stick to the old route) would be argued over by many a study though.

    But I’m not sure if the Met line is in the most desperate need of expansion compared to other directions, such as yet more capacity needed to North and East of the City, somewhere West of Earls Court and yet more new lines through South London etc.

  84. timbeau says:

    @ratoinal plan
    “District line express from Earls court to the City (which died off sometime pre war, I think). ”
    I’m not sure which war you meant, but the powers were surrendered in 1908 according to Subterranea Britannica.

    For all the reasons mentioned above, fitting in a grade separated junction west of either Edgware Road or, particularly Aldgate, or to allow more trains to run east of those points would be incredibly difficult – it is not just the extra width required but the presence of so much beneath the SSL lines – Tube lines and Crossrail for a start. For the more westerly of these two, it would probably mean diverting whichever branch it to be diverted well before Praed Street junction – perhaps as far away as Royal Oak…….. For the more easterly, there is also the river to get under. re-opening the link to the main line station at Liverpool Street is also precluded by the Broadgate as well as the operating constraints of yet another flat junction.

    It has proved easier to design a new line to connect the SWML and the GNML than to stitch together the two “&City” lines. That is basically what Crossrail 2 is. And it has the advantage that you can keep the existing lines open during (and after) construction.

    Similarly, if you want a new tunnel to run east of Paddington into the West End, or east of Liverpool Street into Docklands or onto the GEML, it is probably easier to build new than to interfere with the existing layouts at Edgware Road and Aldgate. Now, why does that concept seem familiar?

  85. timbeau says:

    It would be possible to make the Aldgate triangle look tidier on the map. At present the frequency of service on all three arms approaching the triangle (towards Kings Cross, Whitechapel, and Blackfriars) carry the same frequency, but one side of the triangle 9the south, carries three times as many trains as the other two sides. This is why half the trains approaching on the arm opposite that side have nowhere to go. You can eliminate terminating at Aldgate by having half the services approaching on each arm go each way, instead of the one quarter/three quarters we have at the moment.

    But there would be little point – service frequencies on each of the three arms would be the same – and you would need long runs like Uxbridge/Upminster and Amersham/Wimbledon (via Aldgate). Seems a high price to pay to make the map look tidier.

  86. timbeau says:

    @rational plan
    “If you really needed more capacity off the Metropolitan then a new line from the Baker street to the City would be the answer ”

    They did something like that in 1938, only it ran from Finchley Road, and for the next forty years borrowed part of the capacity of another line before finally getting its own line – and although intended to serve the City it never did – going instead via the South Bank to the new financial quarter.

  87. NickBxn says:

    Back on the TBMs, and the limited market for selling on knock-off Tube diameter ones, unless I missed it somewhere above, or it’s too obvious for even a quip: no one has so far suggested flogging ’em down the Old Kent Road.

    (I guess that even if reconditioned after Kennington, just waiting for a transfer to the Bakerloo would probably mean they get out of prime condition again and need re-reconditiong).

  88. ngh says:

    Re NickBxn,

    Plenty of 400KV electricity tunnels been dug recently under London with original tube size tunnels recently so the market is bigger than you might think many of the parts can be reused in similar sized machines. Much of what is in front of the machines including cutting head the images above would be binned (also see my comments above):

    The sewer TBMs are slightly bigger than the Crossrail ones.

  89. martin formerly Zone6 says:

    There’s been some very well intentioned & fair comment thus far (i always long for the inevitable digression), so i thought i’d throw out an actual experience i had with tfl in 2005.

    I was living in Ruislip and was being offered night work at the new terminal lots in Heathrow, when it came to actually getting to my place of work at 3am though this was & as of 2017 is still impossible from ruislip.

    I asked tfl to consider a connection between ruislip & heathrow to which i got some guff about how every £1 they spend needs £2 in benefit, back to deja-vu employment and whilst i live within 15 minutes of the elizabeth line at AML , i cannot see myself using it to get into my job old job in east london (which i was desperate for a quicker commute from in 2013).

  90. Graham H says:

    @martinformerlyZ6 – it’s easy to blame TfL, but clearly no one can expect a personal transport service from their front door to their workplace (except by private car, taxi, bike, or shoe). I’d like a direct bus from my house to my favourite restaurant but I’d be the only person using it and the cost to the taxpayer would be enormous. Since there are limits on public expenditure, there has to be some sort of fair rationing of what it is spent on. That’s all TfL is doing.

  91. Tunnel Designer says:

    Not really, the 400kV electricity tunnels weren’t that close to tube sized, certainly not close enough for the TBM to be reusable. Most tube tunnels cluster around 12 to 12 and a half ft (3.5 to 3.8m) internal diameter, and to address an old PoP comment linings tend to be about 3 to 6inches thick (75 to 150mm). Thinner ones are SGI, thicker ones are concrete

    National Grid’s recent cable tunnel projects have been either 3m or 4m ID, the larger diameter when they think they will need to add more cable circuits to upgrade later. You can flex the diameter of a machine a bit when you refurb, but not that much. There comes a point where you are basically building a new machine even if you call it a refurb.

    Quite a few large contractors do like to buy their own TBMs, so it is possible the NLE has got bigger from public inquiry as the contractor wants to reuse a TBM they have from an old job. This should be cheaper – rule of thumb was to depreciate the cost of buying a TBM across 3 jobs, refurb costs being not that significant if you own a few machines outright and have your own depot that can do most of the work – so the client rarely objects. The fun comes if the contractor has a slightly smaller TBM and is offering a cost saving.

  92. Southern Heights (Light Railway) says:

    @TD: SGI?

  93. answer=42 says:

    In general, an overcrowded tube (or whatever) line can be usefully extended only if the following conditions hold:
    1. The additional passenger load is dissipated at a point before the capacity limit is reached
    2. The extension is feasible
    3. There is a demand
    4. It is the best way of meeting the demand

    East of Aldgate fails at condition 2. I can think of one other possible extension that might get at least to condition 3. Since my crayons have been taken away, it will remain undescribed. In any case, it is always better to start with the demand for travel and work out how best to meet it.

  94. Anon 26 says:

    SGI = spheroidal graphite iron = Modern Equivalent of Ductile Iron

  95. StephenC says:

    @answer=42 You claim East of Aldgate is not feasible. But is there any proof it has been investigated and discounted, or is that just an opinion? I looked at how it might be done and where it might go very recently (further discussions there, not here).

  96. Graham H says:

    Crayonism lives!

  97. Southern Heights (Light Railway) says:

    That’s where my crayons went!

  98. answer=42 says:

    On East of Aldgate: for a more authoritative answer than I can provide, please review Malcolm’s post from 23 February 2017 at 22:19. Please note the final sentence.

  99. Malcolm says:

    In fairness to Stephen C, he has done his crayoning elsewhere, as requested, and he has provided scope in that elsewhere for anyone who wishes to discuss it.

    For the purposes of discussion here, we will just note that some people believe “East of Aldgate” to be impossible (or practically so), and others do not. Resolving this difference will not occur here.

  100. Southern Heights (Light Railway) says:

    @Malcolm: One of the problems with any extension proposal is that in extending an existing line there might be a sudden increase in patronage at the to be extended end of the line, that comprises people who would otherwise have gotten off earlier to use alternative routes.

    This is one of the (non physical) issues with extending the “unmentionable line”, as has been well recounted here.

    Another problem with the proposal being outlined in the proposal is [Censored] but there I will stop… [You didn’t stop quite soon enough. Malcolm]

  101. Timbeau says:


    I find it difficult to believe there are many people getting off earlier than the terminus of the unmentionable line!

  102. straphan says:

    The trouble with extending the Met is that it is already pretty full. I certainly haven’t seen any half-empty Met trains on the westbound in the PM peak at Farringdon.

    As for the feasibility of the Met extension: I will only say that people may wish to consider whether it would be more feasible using the tail end of the widened lines and the space currently occupied by the terminating platforms at Moorgate (SSL).

  103. timbeau says:

    Too much going on underneath, and certainly not feasible to extend alongside the existing Met, to be able to do much at Moorgate.

    The point about extending the Met was, I understand the same as the Bakerloo – there is supposedly spare capacity going east in the evening peak (and vice versa). (Although I suspect with Liverpool Street so near the east end of the route, it’s not that empty, and having 50% of the trains arrive at LSt almost empty in the morning peak must help keep the platforms clear)

  104. Walthamstow Writer says:

    @ Straphan – if you try to burrow down from the Widened Lines sidings at Moorgate you will simply collide with the enormous escalator shaft just built for Crossrail. Go any further down and you’re in Crossrail’s tunnels. I think extending any lines from Moorgate can go on the “impossible” list now. The place is well and truly boxed in by the very substantial Crossrail structures.

  105. Anon E. Mouse says:

    “I think extending any lines from Moorgate can go on the “impossible” list now.”
    …including the often crayoned Great Northern & City line, of course.

  106. Greg Tingey says:

    A good reality/sense check is to look up the actual ground/under-ground track layouts & positioning, by using Carto Metro
    EG: THIS

  107. Philip says:

    As it’s on my daily commute route, I can confirm that any eastwards extension of Met services (whether on new or current track) would lead to severe overcrowding at Liverpool Street in the morning peak. Unless it was balanced by the suggested-elsewhere idea of having Circle Line trains start from Hammersmith, do one-and-a-half complete loops of the circle, and then turn at Aldgate.

  108. Southern Heights (Light Railway) says:

    @Philip: But of course you then run out of train paths between Baker Street and Aldgate….

  109. Southern Heights (Light Railway) says:

    @Timbeau: At Blackfriars of course! 😉

  110. straphan says:

    @WW: At the risk of incurring the wrath of the moderators, I think if [Speculative comment snipped. Sorry. LBM]

    @Greg Tingey: Carto-Metro maps are lovely and ever so helpful, but certainly not fully geographically accurate.

  111. Timbeau says:


    That wouldn’t be an extension – more of an interpolation.
    Equally impractical though.

  112. Philip says:

    @SLRH: Oh yes, I was forgetting that that proposal involved ending through services at Baker St.

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