NotATrainspott
Established Member
- Joined
- 2 Feb 2013
- Messages
- 3,304
Many thanks, James.
I guess (given sufficient cash) that it could be *made* to work, but in the absence of significant cross-regional demand, the only basis for doing it is to relieve terminal space in rush hours by sending the trains straight through the core. In effect, this is a major point of Crossrail 2 in London, which is only sensible because of the limitations on terminal growth with significant passenger growth expected; is terminal space that limited in Glasgow?
Of course, if Glasgow Crossrail also had a pair of HSR tracks, then the HSR could be Carlisle - Glasgow - Edinburgh which at 225 mph could avoid a Carstairs split, of course....!![]()
Glasgow's tunnels aren't that deep below the surface so a TBM wouldn't have to be particularly deep to clear them easily. The North Clyde and Argyll lines are effectively the same size and in the same position as subsurface tunnels on the London Underground while the Subway tunnels are just a few centimetres narrower than Tube tunnels but not as deep in most places. All of these tunnels were built around the same time back at the turn of the century; any new tunnel for any new purpose would have the advantage of TBMs and more mechanisation in general so we wouldn't have more problems than they did back then.
The tunnelled Crossrail is only really needed for capacity relief but it would have the effect of allowing the city centre to expand northwards and southwards. It would also help the BCR for schemes such as GARL and EARL as through trains under the city could then continue through the airport stations, thus making the train a much more viable option for travel to the airport. The issue with GARL specifically was that it was really just a shuttle operation between Central, Paisley and the Airport which wouldn't be useful for people travelling from most of the rest of Scotland or the surrounding areas of the city. As a result the passenger numbers forecast to go to the airport on GARL were ridiculously small, which was a main driver for cancelling the scheme.
Queen Street High Level station has capacity issues as it is on the end of a two-track 1-in-40 tunnel and is constrained on all sides by streets or other buildings. The EGIP platform lengthening to take 8x23m carriages is effectively all that is ever going to be possible on the current site. Central High Level has many more platforms and less constrictive trackwork but it still has the issue that trains will be sitting around there doing nothing for long periods of time. Glasgow City Council said that the station could be extended to provide 4x400m HS platforms but the issue would be the loss of capacity for normal train services, especially during the construction phase. If we have a tunnelled Crossrail sorted out beforehand, it could free up the majority of the Strathclyde services and leave only diesel and long-distance trains still using the HL platforms at both stations.