Saturday, 24 September 2011

Crossrail, west of Paddington

Crossrail is the major new rail tunnel running under London. Services are currently projected to run from Maidenhead in the West to Shenfield and Abbey Wood in the East. The central core tunnel runs from just west of Paddington to Stepney Green in the east where it splits in two, with one tunnel continuing to the Pudding Mill for Stratford and Shenfield. The other tunnel goes via Canary Wharf to Woolwich for Abbey Wood.

This is a key investment in the rail capacity of London and essential for its future prosperity. Overall, it is fantastic to see it being built, but I do have some comments on the details. In this blog I'll focus on the line west of Paddington.

Heathrow and Reading

The project is described by the London & SE RUS:

5.4.3 There will be 24 Crossrail trains in the highpeak hour across the capital between Paddington and Whitechapel. Beyond this Central London section, 12 of these will replace most inner services on the Great Eastern Main Line (GEML) and 10 will replace most inner services (including Heathrow Connect) on the Great Western Main Line (GWML) route. There will also be 12 trains in the high-peak hour via a new cross-river tunnel route to Abbey Wood via Canary Wharf. It can be seen from the above that 14 of the 24 peak Crossrail trains will run no further west than sidings just outside Paddington.

The RUS then goes on to discuss whether the unused 14tph in the west could be better utilised. It proposes to rebalance the GWML (Great West Main Line) to have 20tph on the fast lines from Reading to Paddington and 16tph on the slow lines running to Crossrail. The fast line service of 20tph would be

  • 10tph inter-city, from places such as Exeter, Bristol and Cardiff
  • 6tph outer-SE, from places such as Oxford and Newbury
  • 4tph Reading express, peak-time capacity providers from Reading and Maidenhead, with alternate stops at Twyford and Slough (running on the slow line until Maidenhead or Slough, then on the fast lines)

while the slow line service of 16tph would be:

  • 4tph to Reading, stopping at some but not all stations
  • 2tph to Slough, stopping at some but not all stations
  • 10tph to Heathrow, stopping at some but not all stations

This means that Greenford, Henley and Twyford would have no through services to London, and the Heathrow Express service would only run off-peak.

Overall, this is an excellent starting point to discuss the London based GWML services. It makes far better use of Crossrail (which is otherwise very under-used in the west), and links in Heathrow to a much more appropriate level. The committed scheme of terminating 14tph just west of Paddington is patently barmy.

Would I change anything from the RUS plan?

Firstly, I believe that the Heathrow service should run into Crossrail all-day, and the Heathrow Express shuld cease to exist in its present form. This will require negotiations with BAA, but the benefits are clear, with Crossrail providing a much wider range of destinations and at significantly better quality than the Picadilly line.

Secondly, I dislike the "skip-stop" nature of the slow line proposals, which will make it hard to predict which stations any given train stops at, making moving between outer London stations rather difficult. What I would like to see is some detailed analysis on whether some sections of 6 tracks could be provided on the GWML. These would allow fast trains to overtake slow ones and provide a more traditional service, such as 4tph all stations to Slough, 4tph fast to Slough then all stations, 4tph Heathrow express and 4tph Heathrow slow.

Link to Watford?

The GWML proposals above take 16tph of the 24tph from peak-hour Crossrail, but the RUS also outlines a proposal for the other 8tph. It proposes a new link in the Old Oak Common area to the WCML (West Coast Main Line) allowing the slow line services from Tring and Watford to run onto Crossrail. The RUS makes no detailed service proposals. A key point is that this provides spare capacity at Euston to assist with the rebuild for HS2.

Sidestepping my views on HS2 for a minute, the WCML link makes some sense. The GWML and WCML are very close at that point, and geographically, WCML passengers are in fact entering London from the west, not the north west. Given a free hand, I would have preferred to see the High Wycombe, Aylesbury or Hounslow routes developed, but if HS2 continues as is, then I have to support the WCML link proposal.

The exact choice of routing is interesting however. The proposal suggests 8tph in peak and 6tph off-peak. In addition to the Watford to Tring section which should be served, it is important not to forget the London Overground all stops service from Harrow & Wealdstone to Watford which shares tracks with the Bakerloo from Harrow to Queens Park. This service runs 3tph, and could potentially be transferred to Crossrail. However, this would require additional investment in junctions and electrification. As such, it is likely that these services will be unable to be picked up.

I also note that in my opinion, the Old Oak Common interchange would be key. Stratford is a classic example of getting it wrong. The HS1 station is disconnected from the main station, requiring an expensive DLR extension to connect it up, making it highly inconvenient for interchange. It is vital that the Old Oak Common station is properly designed and planned to integrate the HS2 platforms, GWML platforms and the WCML platforms. They must be a single integrated station, not overly spread out - the passenger must come first.


The committed Crossrail service in the west is essentially incomplete. It runs to Maidenhead, when Reading is more natural and probably cheaper. It only sends 4tph to Heathrow, which makes no sense. And it only sends 10tph beyond Paddington, which is a huge waste of the central tunnel. The RUS proposals for peak of 8tph to Watford and 16tph to Heathrow/Reading make a lot more sense, although I would prefer to see new sections of 6 tracks on the GWML to allow a more standard split of services. I would also prefer to see the Heathrow Express scrapped entirely in favour of services through Crossrail.

Comments welcome on the Crossrail line west of Paddington!