I take it you mean Hitchin, where they are planning to bring the construction material in by road when there is a perfectly good railway available, although it's still a good idea. At Welwyn, separating out the fast lines and building a viaduct/tunnel combination that's good for 155 mph would be a good idea, allowing any future IC250 equivalent the possibility of 155 all the way from Hatfield.
Sorry I did mean Hitchin. I got confused.
As far as the viaduct/tunnel combo at Welwyn is concerned, I imagine it would be on the slow lines (I think the existing viaduct is on the fast lines) so a 155mph line speed would not be needed.
Plus
Rebuild the down slow Peterborough-Helpston Jcn
Extra bore at Stoke Tunnel, thus four tracks all the way to Grantham.
Are 4 tracks needed north of Peterborough? I can understand it south of there, due to the stoppers. I would have thought north of Peterborough wouldn't be a priority though, even with the freight.
Or a rearranged diveunder at the site of the old Barkston Jcn
Possibly. Where is this? I couldn't find any trace of it on multimap.
Better done to the south at Black Carr, to take up Leeds services over the fast lines, with two new platforms between Doncaster station and the Plant (currently rusty sidings)
Donny is a tough one. Ideally I would want to separate all of the flows, but don't want it to turn into a mess. Going with your plan for a second, I would do the following:-
Platform 1 (existing) used for Goole services etc.
Platform 3 (existing) used for up fasts on ECML from York
(Keep through tracks for non-stoppers)
Platform 4 (existing) used for down fasts to York (and beyond)
Platform 8 (existing) used for trains to Sheffield
Platform 9 (new through) used for trains from Sheffield
Platform 10 (new through) used for Leeds->London
Platform 11 (new bay) used for Leeds-Doncaster
Platform 12 (new through) used for London->Leeds
You would then end up with Leeds-London and Doncaster-Sheffield trains crossing paths south of the station. It also restricts Goole type services from going to Sheffield, as they would have to cross just about everything. I realise this is not an ideal situation, but I don't know what is.
I'd be considering Harrogate-Ripon-Northallerton as well, providing a KX-Donny-Ulleskelf-Tadcaster-Wetherby-Harrogate-Ripon-Northallerton-Sunderland route.
There are two problems with Harrogate-Ripon-Northallerton. Firstly, there's a lot of mileage of new track there, for not a lot of benefit (the population of Ripon is only 16,000). Secondly, I don't see a good way of getting the railway anywhere close to the city centre. Then again it has been a while since I was last there.
I'd consider a Swindon-style solution, with platforms on the up freight line (not repeating the mistake of building on top of the down loop, which they did there)
Possibly. I've never been to Swindon and don't know the layout. I'll look into it.
Metro extension or heavy rail? If we're considering Metro extensions, how about St James'-Metrocentre
Dealer's choice. I don't know. Giving Consett good links to Newcastle and Durham would be a good thing though.
Add
Morpeth avoiding line
Quadruple as far as the south of that
Divert Chathill services to Alnwick, increase to half-hourly
Consider Metro extensions onto the Blyth and Tyne, with an additional line direct to the old east bays at Newcastle Central
Newcastle and beyond aren't my strong point, although if you could see your way clear to getting me a train to Lindisfarne that would be brilliant!
Now onto my plan for the East Midlands, which involves building HS2 on the alignment of the old GCR London Extension and reopening the Woodhead Tunnel. This absorbs a lot of MML traffic, and allows EMT to add stops to their services south of Leicester, thus increasing the local service, and hopefully reopening the stations between Bedford and Kettering. All important stations (Nottingham Victoria, Sheffield Victoria, Manchester Wherever and Leeds City) would have two dedicated international platforms for cross-channel operators, fully sealed and with check-in facilities. The Woodhead route would modify traffic patterns into Manchester Piccadilly, where several flyovers would sort it out more effectively. A pity it's impossible to reopen Manchester Central. It would also allow Virgin to divert one Manchester express per hour to Glasgow and XC to send some traffic to Liverpool (access to HS2 between Brackley and Sheffield would compensate for this).
I did have a fairly wacky plan once. There's a disused viaduct leading it's way into Leeds City Centre. I think it took trains from Huddersfield. The end of it could be accessed from the Leeds-Wakefield line.
My plan was to (assuming any new high speed line would come from around there), put the high speed services onto this viaduct (they would be slowing down to terminate at Leeds anyway). The viaduct would then be raised at the Leeds Station end, similar to the one carrying Aston-bound trains from Birmingham New Street. The HS line would then go over the Leeds western approach and onto new platforms over the car park. Access to the platforms would be from the new concourse where McD's and Starbucks are currently located. Unfortunately, I can't imagine trains carrying on from there, so it would have to be a dead end for a spur, rather than a through line.