HS3 and beyond (fantasy thread)

[po8crg]

So, if you got a couple of hundred billion quid to extend a HS network across GB after HS2 is finished, what would you build?

This is assuming that HS2 will go ahead more or less as planned.

Here's my thoughts:

1. Fully tunneled HS2-HS1 connection in North London, so through trains can run
2. Connection from HS2 to Liverpool, probably along the lines of the 20 miles more proposal for a junction at Culcheth and a Lime Street or Exchange station.
3. New junction in Ardwick/Longsight and a line across the Pennines to connect to the eastern arm of HS2 between Leeds and Wakefield
4. Extend HS2-East to Newcastle
5. Extend HS2-West to pass between Glasgow and Edinburgh and run on to Stirling/Perth/Dundee
6. Build a new HS line from Edinburgh to Glasgow connecting to HS2-West between the two cities, so there is an Edinburgh-Glasgow shuttle and also connections from either city to go both North and South
7. Extend from Dundee to Aberdeen and then Inverness.
8. Build a line from Heathrow to Gatwick and then on to Ashford, giving a full-circle around London
9. Build a new line from Toton to London, branching to connect direct to HS1 at Stratford and the other branch coming into a new station built in Somers Town between Euston and St Pancras
10. Build a line Toton-Peterborough-Cambridge-Norwich-Ipswich and then connecting to the Toton-London line just outside London.
11. Build a line from somewhere in South London (Waterloo if there's room, perhaps between the station and the Eye?) through Gatwick to Southampton-Bristol
12. Connect Bristol to Birmingham
13. Build a new Severn Bridge and connect to Newport, Cardiff and Swansea
14. Bristol-Exeter-Plymouth-Penzance

I think you'd be looking at Irish Sea tunnels to go beyond that.

 

[Gathursty]

I'd like to see the port stations connected by a HS line:

Milford Haven
Pembroke Dock
Fishguard
Newhaven Harbour
Harwich International
Stranraer
Ardrossan Harbour
Heysham Port
Portsmouth Harbour

Primarily for foot passengers benefit but secondly for freight provided there is more investment in that area. Other obvious seaside stations such as Liverpool, Hull and others I've not thought of just yet can be added to the above.

 

[swt_passenger]

So, if you got a couple of hundred billion quid to extend a HS network across GB after HS2 is finished, what would you build?

Isn't that what this thread (that you must have missed a few lines down the page) was about:

http://www.railforums.co.uk/showthread.php?t=89719

 

[po8crg]

Yes. Sorry, this was meant to be on SSC.

 

[gordonthemoron]

start again from scratch, Bishop Auckland-Darlo-Stockton/Newport HS line

 

[RichardN]

ok, here is what I'd do. Underground station with four platforms 2 Easbound and 2 Westbound which takes advantage of the length of trains and has exits at Euston and St Pancras. Lines to HS1 and the main line curving round in tunnel to another station with 2 x NB and 2 SB platforms with one exit connecting somewhere to the circle line and the other at Waterloo, then down in tunnel on a new alignment to and underground station at Gatwick with one exit at the North Terminal and One at the South Terminal, then onward to a terminus serving Brighton on a new alignment.


The advantage of this. With a Spur to Heathrow, you can run commuter services...

Brighton - Gatwick - London (s) - London (n) - OOC - Heathrow
Kent HS - London (n) - OOC - Heathrow

And mainline HS services...

to a mix of London, Gatwick, Brighton, Ashford. I'd construct turnback facilities near the intermediate stations.

 

[59CosG95]

ok, here is what I'd do. Underground station with four platforms 2 Easbound and 2 Westbound which takes advantage of the length of trains and has exits at Euston and St Pancras. Lines to HS1 and the main line curving round in tunnel to another station with 2 x NB and 2 SB platforms with one exit connecting somewhere to the circle line and the other at Waterloo, then down in tunnel on a new alignment to and underground station at Gatwick with one exit at the North Terminal and One at the South Terminal, then onward to a terminus serving Brighton on a new alignment.


The advantage of this. With a Spur to Heathrow, you can run commuter services...

Brighton - Gatwick - London (s) - London (n) - OOC - Heathrow
Kent HS - London (n) - OOC - Heathrow

And mainline HS services...

to a mix of London, Gatwick, Brighton, Ashford. I'd construct turnback facilities near the intermediate stations.

So you'd want to construct an "anti-Blackfriars" by putting the platforms under the Thames? THAT is going to be very difficult indeed!

 

[RichardN]

So you'd want to construct an "anti-Blackfriars" by putting the platforms under the Thames? THAT is going to be very difficult indeed!

Well it wouldn't be essential. The goal was to maximise convenient interchange with both underground and regional rail. You'd have a connection with h&c, metropolitan and circle at st. Pancras anyway.

 

[HSTEd]

Still think the best option for construction of an underground box in Central London is in one of the parks, dig it up, put the box in and then cover it in again.

 

[NotATrainspott]

Still think the best option for construction of an underground box in Central London is in one of the parks, dig it up, put the box in and then cover it in again.

Beneath a Royal Park. In the spirit of looking at possible options, we investigated the potential for developing a station underneath one of the central London Royal Parks. We looked at possible sites in Green Park, Hyde Park and Regent’s Park. We envisaged using a cut and cover methodology so that the park would be reinstated after construction with the only visible structures within the park being a station entrance, associated access provision, emergency exits and the vent shafts that would be necessary to provide ventilation and a means for smoke to escape in case of fire. Construction of this nature in a green-field site poses relatively few engineering issues, mainly associated with aligning the underground box to fit with existing tunnels. Of the Royal Park locations, Regent’s Park offered better connectivity than Green Park or Hyde Park. This option had made it through stage one on the basis that we required further information from a planning and sustainability perspective.
Gaining permission to build in any Royal Park would require a significant shift in the protection afforded to these sites, which have remained largely unchanged for nearly 200 years. We took the view that further consideration of a terminal station in any Royal Park should only be undertaken as a matter of last resort. We recognise that there would be significant opposition to building in these open spaces that have been safeguarded for the enjoyment of Londoners and visitors alike and which are London landmarks. We therefore concluded that no options to build beneath the Royal Parks should be taken forward.

High Speed Rail London to the West Midlands and Beyond - Chapter 3 [Document Page 57, PDF Page 11]

It will be quite the challenge in getting public approval for such a station, but if HS2 goes well and no other sensible options appear then it might just happen one day.

 

[HowardGWR]

High Speed Rail London to the West Midlands and Beyond - Chapter 3 [Document Page 57, PDF Page 11]

It will be quite the challenge in getting public approval for such a station, but if HS2 goes well and no other sensible options appear then it might just happen one day.

It did not seem to me to be a strategic approach by the document to say that the idea would not be taken forward because the promoter is afraid of promoting it. If the proposal for Regents Park means that it will be Regents Park again after construction, what could possibly be the beef?

 

[pablo]

A b***dy big car park was built under Hyde Park in the sixties. What's changed?

 

[NotATrainspott]

A b***dy big car park was built under Hyde Park in the sixties. What's changed?

Presumably the same reason that a two-track railway today is a far more controversial than any motorway ever built in the UK. Once the public know what this HSR thing is all about, and their opposition to HSR is properly replaced with an opposition to further road schemes, the royal park station idea might be as acceptable as the car park was back then.

I think the concept of an HSR station under a royal park is actually not a bad one. In particular, it gives a chance to build London's equivalent to Berlin Hbf with many mainlines' worth of platforms all joined up in one massive interchange. By the time HS3 rolls about there certainly won't be very much undeveloped land left for a 10x400m platform station in London as regeneration works on the economically depressed areas of the city and around the existing rail hubs. Building a park station would be an interesting engineering challenge with the amount of spoil needing removed - it would most likely require at least one of the approach tunnels to be completed first so that it can be removed without using lorries.

 

[pablo]

.........Building a park station would be an interesting engineering challenge with the amount of spoil needing removed - it would most likely require at least one of the approach tunnels to be completed first so that it can be removed without using lorries.

rather like the Channel Tunnel. We could call the dump Shakespeare Hill.

 

[HSTEd]

There is essentially unlimited space for platforms although the approaches would have to be rather serpentine low speed affairs - which is probably not a problem if it is not a through station.
Since you would have to dig down quite far you might be able to get a Canary Wharf style 'underground cathedral' for the Concourse which would presumably be stacked above the platforms themselves - high ceilings would reduce the amount of spoil required to 'refill' the hole.

 

[59CosG95]

There is essentially unlimited space for platforms although the approaches would have to be rather serpentine low speed affairs - which is probably not a problem if it is not a through station.
Since you would have to dig down quite far you might be able to get a Canary Wharf style 'underground cathedral' for the Concourse which would presumably be stacked above the platforms themselves - high ceilings would reduce the amount of spoil required to 'refill' the hole.

Presumably the platforms would be tucked under the concourse walls in a similar fashion to Canary Wharf? Or will they be classic, LU-style bored tunnels?

 

[HowardGWR]

There is essentially unlimited space for platforms although the approaches would have to be rather serpentine low speed affairs - which is probably not a problem if it is not a through station.

I don't get that. If it is a through station, then surely the approach speeds can be higher than with a terminus?

 

[NotATrainspott]

A through station under London would just be one set of platforms with a termini's worth of station throat at either end, as there would be no trains not stopping there, so it doesn't really matter how slow the approaches are. Even if only half of the services continued through to the other side of London, even only to somewhere like Heathrow or Stansted, it would still reduce platform requirements considerably.

 

[59CosG95]

A through station under London would just be one set of platforms with a termini's worth of station throat at either end, as there would be no trains not stopping there, so it doesn't really matter how slow the approaches are. Even if only half of the services continued through to the other side of London, even only to somewhere like Heathrow or Stansted, it would still reduce platform requirements considerably.

I wouldn't say just 1 set of platforms is good for expansion. I'd say that at least 2 sets would be needed in case one set went out of commission. On the Jubilee line, there are only 2 possible destinations-Stanmore and Stratford, whereas a London thru-station would cater for destinations all over the country, if not the continent!

 

[NotATrainspott]

I wouldn't say just 1 set of platforms is good for expansion. I'd say that at least 2 sets would be needed in case one set went out of commission. On the Jubilee line, there are only 2 possible destinations-Stanmore and Stratford, whereas a London thru-station would cater for destinations all over the country, if not the continent!

By 'set of platforms' I mean four or six or so, not a single pair. There wouldn't be any need for fast pointwork on either side as all trains would stop. Depending on how the through route would connect into HS1 and HS2, it might be possible to have all London terminators go to Euston or St Pancras and only have through-running trains going to the through station.

 

[HSTEd]

Presumably the platforms would be tucked under the concourse walls in a similar fashion to Canary Wharf? Or will they be classic, LU-style bored tunnels?

I would forget the bored tunnels and just go for a cut and cover 'cavern' with the platforms supporting pillars which hold up the concourse and the structures above it.
Presumably that is what was done at Canary Wharf?
Thanks to the large concourse we get (same areas as all the platforms) it becomes practical to completely seperate departing passengers from arriving ones with seperate entrances and so on, allowing an enormous people moving capacity.

Attempting to bore circular section tunnels for the pltforms is a nightmare thanks to the shape of the required loading gauge

I don't get that. If it is a through station, then surely the approach speeds can be higher than with a terminus?

Not really, because we only have a certain length of park to fit the station into, which is unlikely to be more than ~700m even if the station is orientated to maximise this figure.
Trying to fit ~405m platforms, the frangible buffer length and the station throat into that is asking for trouble and unless the tracks have collapsd into a small number of running lines before the end of the park the cost will skyrocket thanks to demolitions of adjacent buildings or attempts to bore out the remainder of the throat.
Now try it without the frangible buffer length but with additional overlaps and a whole second station throat.
There is a reason Stratford international is 1000m in length or more.

A through station under London would just be one set of platforms with a termini's worth of station throat at either end, as there would be no trains not stopping there, so it doesn't really matter how slow the approaches are.

There is slow, and there is 'butting up against the minimum curve radius requirements'.
Trains would potentially have to slow down so much they will block up the throat as they have to crawl several hundred metres at near walking pace.