High speed rail has its benefits, but we don’t have to build it all straight away: use high speed to enhance the existing rail system, not replace it.
Normally, it’s a good idea to separate fast and slow railway services. There are multiple intermediate stops on almost all corridors, so you need four tracks to run fast services. Approaching London, you ideally need six tracks, so the urban stopping service is separate. That’s the situation on the West Coast Main Line – six tracks to Watford, four tracks (mostly) to Crewe.
Around London, many of the main lines were four-tracked decades ago, in the days when there were far more freight trains. This typically extends beyond the limit of outer commuter services, allowing the fast trains a clear run. This is why there hasn’t been the pressure to build high-speed lines – we already have an extensive network of fast lines.
With the exception of Kent (where there had never been much four-tracking), the sensible option has been to increase linespeeds, build flyovers, and extend the four-track network. And so it might continue if it weren’t for Milton Keynes.
The two largest rail markets in Britain are London to Manchester and London to Birmingham. They are large enough to justify half-hourly non-stop services, but the infrastructure does not allow this. At the London end the line is getting close to capacity. We are getting to the point where either everything has to stop at Milton Keynes, or nothing.
Approaching Birmingham and Manchester, there are sections of two-track railway, and the fast services have to run between stoppers. To make this fit, the fast services have a couple of intermediate stops. These extra stops mean there are more services to Birmingham/Manchester, and that partly compensates for the loss of speed, but there isn’t much value running more than three trains an hour.
With Milton Keynes planned to expand, the simplest option is to stop everything at Milton Keynes, in much the same way as everything out of Paddington stops at Reading. This slows all the fast trains by about five minutes. So the high speed line isn’t really about solving a capacity problem, it’s more that the capacity problem reduces speed, making a high speed line more beneficial.
The engineers have identified a route for a new line, and have ended up proposing a tunnel almost all the way from central London to Amersham – about 40km. To justify the cost of this, the route to Birmingham and Manchester needs to be ultra-fast throughout, and the line needs to be full from the outset, with branches to anywhere big enough to fill a train. This intensity of service also requires a major expansion of Euston station, demolishing several blocks of social housing in the process.
The expensive parts of the high speed line are the new terminal stations and the tunnelling into the cities. The French typically don’t do either of these – they have concentrated on building new lines between cities. Now that we’ve identified just how expensive the full scheme would be, I think it’s time to consider an intermediate option that leaves the most expensive sections to later.
Starting from Euston, I’d suggest maximising the number of 260m platforms within the existing station, and expanding the concourse, but not increasing the footprint or trying to provide 400m platforms.
I’d then use the existing fast lines to at least Headstone Lane (between Harrow and Watford), and start the high-speed line from there. That halves the tunnelling, but allows the full scheme to be implemented at a later date.*
The high speed line would then run as proposed to Berkswell on the outskirts of Birmingham, before diverting onto the existing route to Birmingham International and New Street. Capacity approaching Birmingham would be increased by four-tracking from Berkswell to Adderley Park, and providing additional flyovers at Proof House (the junction just before New Street) to make it conflict-free. Platform capacity at New Street would be increased by running services through, rather than terminating. This doesn’t quite create a perfect high-speed route into Birmingham, but it spreads the capacity benefits more widely, allowing more local and more semi-fast services.
Services to Manchester would diverge from the high speed line south of Rugby, on a new link that would join the existing main line just north of Rugby. The existing line is mostly four-track and fast for 125 km, and does not need to be duplicated. Just before Stafford, there is a gap in the four-tracking which probably needs a 5 km new line, looping south of Shugborough. At Crewe, there will need to be a new flyover at the south end, and the freight underpass at the north end will need to be upgraded.
The existing route from Crewe to Manchester is fairly fast, albeit mostly two-track and with a couple of intermediate stops required. The proposed route with a long tunnel via the airport is hard to justify. A better bet would be building a branch a bit further north, alongside the M62 then joining the line to Manchester Victoria via Eccles. This would be fast, with no intermediate stops. There would probably need to be new platforms at Manchester Victoria, but there is plenty of space.
The line will be almost full with fast services to all the main West Coast destinations, but there will be some spare capacity. It will be hard to justify a high-speed branch to Leeds: the costs will be high and the cities are smaller. Instead I would suggest a short branch towards Derby, with high-speed services to Sheffield and Nottingham, using existing lines.
It seems more likely that improvements to Leeds will come from upgrades to the East Coast Main Line. The key bottleneck is south of Hitchin, where there are too many outer-suburban services on the main line. The solution may be to use the fast lines out of St Pancras to Bedford, and make a new line alongside the A421 to St Neots. This would provide enough capacity to run additional trains non-stop to Leeds.
Rather than build an all-new high speed line, I think a greater improvement can be made by selective new build and four-tracking more of what we already have. That way the benefits will be felt more widely, and the new capacity will be put to good use, rather than duplicating what we already have. In a small country, it’s the ability to run non-stop that makes the critical difference to speed.
The map shows the existing four-track railways (in orange), the existing and suggested high-speed lines (in red), and the new four-tracking on the approach to Birmingham (in green).
* There are other possibilities, using existing major road corridors through the Chilterns. These are slightly slower, and deviate more from the full scheme, making it more expensive to implement the full scheme later. The minimum requirement is to leave the existing line before the first station north of Watford (Kings Langley).