Would we need a GWML high speed line?

[Sad Sprinter]

Is the GWML overcrowded enough to justify its on HSL? If so, what would be the best alignment for it?

 

[JonathanH]

Is the GWML overcrowded enough to justify its on HSL?

No

If so, what would be the best alignment for it?

The best alignment would need to serve the most population to be viable. Clearly Bristol and South Wales is one target but so is the South Coast at Southampton and Bournemouth, so it might go out in the direction of Basingstoke then split for Southampton and Bristol in an underground delta junction. Stops would be Old Oak Common, under the GWML station, Southampton, Bristol and Cardiff, with a connection near Westbury to the line to Taunton.

Not happening any time soon, if ever. It has been pointed out previously that HS2 is the only viable route for a brand new High Speed Line on the British mainland, which seems about true. The population of the Bristol, Cardiff, Solent and Dorset conurbations could never justify the capacity such a line would add.

 

[A S Leib]

Stops would be Old Oak Common, under the GWML station, Southampton, Bristol and Cardiff, with a connection near Westbury to the line to Taunton

Although OOC to Bristol via Southampton wouldn't make much sense, as that's 200 km whilst HS1 between Stratford and Ebbsfleet's ~147 km/h, so around 95 minutes assuming ten minutes from departing Paddington to departing OOC and three minutes to call at Southampton compared to a minimum of 93 minutes now. It could save an hour between Cardiff / Bristol and Southampton, but again improving existing lines is probably better. (Assuming that a straight line could somehow be built between Old Oak Common and Southampton, and between Southampton and Bristol.)

Paddington to Exeter calling at OOC and Southampton on straight lines would be around 111 minutes, but I don't think Devon / Cornwall to London (or even to the eastern south coast; probably better improving connections at Westbury) needs that much capacity, it would only save around seventeen minutes and would probably have to go through the South Downs, New Forest, Cranborne Chase, Dorset and East Devon AONBs, so that isn't likely either.

 

[JonathanH]

Although OOC to Bristol via Southampton wouldn't make much sense, as that's 200 km whilst HS1 between Stratford and Ebbsfleet's ~147 km/h, so around 95 minutes assuming ten minutes from departing Paddington to departing OOC and three minutes to call at Southampton compared to a minimum of 93 minutes now. It could save an hour between Cardiff / Bristol and Southampton, but again improving existing lines is probably better. (Assuming that a straight line could somehow be built between Old Oak Common and Southampton, and between Southampton and Bristol.)

Yes, going from London to Bristol via Southampton wouldn't make sense. I was suggesting a delta junction somewhere near Basingstoke. London, Southampton and Bristol would just be points on a triangle, but instead of being an actual triangle, the lines would meet at a delta junction.

 

[WizCastro197]

Yes, going from London to Bristol via Southampton wouldn't make sense. I was suggesting a delta junction somewhere near Basingstoke. London, Southampton and Bristol would just be points on a triangle, but instead of being an actual triangle, the lines would meet at a delta junction.

Are 2 branches financially viable? One to South Wales (Cardiff etc) and one to perhaps Bournemouth via Southampton and Basingstoke or does this defeat the purpose as you have the original lines? I am somewhat mystified by this delta junction as well, what would it be?

 

[Nottingham59]

If the issue is overcrowding on the GWML, then the answer is to build a surface terminus at Old Oak Common, with very long platforms, and split and join services to Bristol, Cardiff and Exeter at an extended Bristol Parkway.

They could have done that for the WCML (with the split/join location at Basford Hall just south of Crewe),and provided the same capacity uplift that HS2 will bring, at around one tenth of the cost.

The Elizabeth Line (1500pax @ 30tph = 45,000/h) should be able to handle three 9-car Class 800s strung together arriving at 10tph (650x3pax @ 10tph = 19,500/h), but I think any more would need increased local distribution capacity at OOC.

 

[JonathanH]

I am somewhat mystified by this delta junction as well, what would it be?

Essentially the line would leave London in the direction of Basingstoke (maybe Micheldever). At Micheldever, the line would split for Bristol and Southampton. However, there would be a third side of the triangle so that high speed services could run from Bristol to Southampton, predominately on the lines from London, with the junction broadly in the same place (near Micheldever).

 

[WizCastro197]

Essentially the line would leave London in the direction of Basingstoke (maybe Micheldever). At Micheldever, the line would split for Bristol and Southampton. However, there would be a third side of the triangle so that high speed services could run from Bristol to Southampton, predominately on the lines from London, with the junction broadly in the same place (near Micheldever)

Ah thanks for taking the time to explain this, it makes so much sense now. If you are splitting after Basingstoke, would it be worth having a station there?

 

[JonathanH]

If you are splitting after Basingstoke, would it be worth having a station there?

No, because just like HS2 not having a stop south of Birmingham, it would involve trains slowing down on a high speed section and the passengers at intermediate stations could have trains on the classic lines.

 

[The Planner]

They could have done that for the WCML (with the split/join location at Basford Hall just south of Crewe),and provided the same capacity uplift that HS2 will bring, at around one tenth of the cost.

You will have to elaborate there.

 

[Wokingham]

im going to have to google loads but im sure first group proposed a gwr high speed route

 

[JonathanH]

You will have to elaborate there.

I think the idea is that three (or maybe more) Pendolinos would run together from a long platform in London to a long platform in Crewe, then split for Liverpool, Glasgow and Manchester, thereby only taking up one path on the WCML.

The cost of the long platforms would be cheaper way of enhancing capacity than a high speed line.

 

[ChiefPlanner]

Back in about 2010 - there was a high level , blue-sky think tank meeting in the splendid City Hall at Cardiff.

Then - being true to my name - I tabled a proposal (crayonista par excellence) of a Heathrow (linked of course to Crossrail as it was in those days) - to a new build to Reading but skirting the M4 and not demolishing the town - to a route towards the West with a branch to Basingstoke and a rebuild of the route from Eastleigh towards Pompey , giving substantial relief to the SWML as it was then - with the "Western branch" taking on the coal train free WR from Wooton Basset towards Parkway with an improved route into Temple Meads. The South Wales Direct line has really only 2 trains an hour and is fairly well engineered - 140 mph ought to be achievable.

No need for huge new build ....

 

[Wokingham]

Back in about 2010 - there was a high level , blue-sky think tank meeting in the splendid City Hall at Cardiff.

Then - being true to my name - I tabled a proposal (crayonista par excellence) of a Heathrow (linked of course to Crossrail as it was in those days) - to a new build to Reading but skirting the M4 and not demolishing the town - to a route towards the West with a branch to Basingstoke and a rebuild of the route from Eastleigh towards Pompey , giving substantial relief to the SWML as it was then - with the "Western branch" taking on the coal train free WR from Wooton Basset towards Parkway with an improved route into Temple Meads. The South Wales Direct line has really only 2 trains an hour and is fairly well engineered - 140 mph ought to be achieva
No need for huge new build .yes t

thats the one with a parkway at greenpark? what happened to all the pics articles?

 

[The Planner]

I think the idea is that three (or maybe more) Pendolinos would run together from a long platform in London to a long platform in Crewe, then split for Liverpool, Glasgow and Manchester, thereby only taking up one path on the WCML.

The cost of the long platforms would be cheaper way of enhancing capacity than a high speed line.

I thought it may be that, so still rebuilding Euston and the entire throat and approaches.

 

[Nottingham59]

You will have to elaborate there.

I will do just that, but in a separate thread, and post a link here when it's ready.

See below in this thread

 

[Irascible]

Paddington to Exeter calling at OOC and Southampton on straight lines would be around 111 minutes, but I don't think Devon / Cornwall to London (or even to the eastern south coast; probably better improving connections at Westbury) needs that much capacity, it would only save around seventeen minutes and would probably have to go through the South Downs, New Forest, Cranborne Chase, Dorset and East Devon AONBs, so that isn't likely either.

I don't think there's a way of avoiding everything bar a torturous route or a heck of a lot of tunnelling, but getting to Bournemouth & swinging back to Taunton would avoid most of the AONBs at least. The coastlone from Weymouth to most of the way to Exeter is a World Heritage Site to add on top of the AONBs

On balance I'd rather any investment was in travel towards the North than London, other than adding some capacity back to the existing WoE line.

 

[Kilopylae]

If the issue is overcrowding on the GWML, then the answer is to build a surface terminus at Old Oak Common, with very long platforms, and split and join services to Bristol, Cardiff and Exeter at an extended Bristol Parkway.

Unless I'm misunderstanding, doesn't this badly shaft the south west on journey time?

 

[PTR 444]

Unless I'm misunderstanding, doesn't this badly shaft the south west on journey time?

Running a high speed London - South West service via Bristol would still be very competitive on today's timings. It was of course Brunel's original route for GWR trains before the Reading - Taunton Line was completed.

 

[Benjwri]

then the answer is to build a surface terminus at Old Oak Common, with very long platforms, and split and join services to Bristol, Cardiff and Exeter at an extended Bristol Parkway.

What about Reading, Didcot and Swindon? Bristol Parkway seems an odd point to split, any train at Bristol Parkway is going to be going to Cardiff, and diverting every service from the West there would add a lot of journey time.

It's unfortunate Paddington cannot be extended, I would argue there is merit to the idea of splitting at Reading, since the capacity choke point currently is only really between Reading and London.

I feel the only way to solve the GWML issues is some form of CBTC/ETCS and removing fixed block signalling to allow frequency uplift. It would only be needed between London and Reading.

 

[Nottingham59]

I think the idea is that three (or maybe more) Pendolinos would run together from a long platform in London to a long platform in Crewe, then split for Liverpool, Glasgow and Manchester, thereby only taking up one path on the WCML.

The cost of the long platforms would be cheaper way of enhancing capacity than a high speed line.

That's it, exactly. If you're going to split and join trains, then you might as well do it properly and get some significant capacity benefits.

I thought it may be that, so still rebuilding Euston and the entire throat and approaches.

Not at all. If you terminate the long trains at Old Oak Common, you don't have to touch Euston at all. That's £2bn saved on the station and £1.6bn saved on the tunnel from OOC to Euston already. And you don't have to build HS2 phase 1 or phase 2A either

Unless I'm misunderstanding, doesn't this badly shaft the south west on journey time?

Yes, probably. But this idea is about capacity rather than speed.

Below is what I had in mind for the WCML as an alternative to HS2. But the idea works even better for the GWML.

Build a surface station at Old Oak Common, connected to the WCML fast lines, with 10 x 795m platforms. Include platforms to the Elizabeth Line (perhaps two EL stations close together to save walking). The station can also have access to the Bakerloo line at Kensal Green and it would make sense to divert the Overground lines to this station too.

To increase WCML capacity, run three Pendolinos (or their follow-on replacements) connected together as trains 795m long (3x265m), terminating at Old Oak Common. These run non-stop to new "splitting stations" located at:

• Basford Hall (which replaces the current Crewe station) from where separated units can run to Manchester, Liverpool, Preston etc.
• Near Daventry, from where the separated units can run to Birmingham, Trent Valley (and I would add a new line to Wigston for Leicester, Nottingham, Sheffield and Leeds).

These are the numbers:

• HS2 at full capacity can carry 1100 x 17tph = 18,700 pax/h, assuming they are all seated.
• The WCML fasts have a current capacity of 20 x 11-car Pendolinos per hour assuming 3 minute headways = 589 x 20tph = 11,780 pax/h, again assuming all seated.
• Running 795m trains at three minute headways would give a seated capacity of 589x3 x 20tph = 35,340 pax/h. The WCML uplift would be +23,560pax/h which is greater than the capacity of HS2 at its full extent.

How to handle that many passengers at OOC?

• The Elizabeth Line currently has 6tph to Heathrow, 6 tph down the GWML, and 12tph terminating at Paddington. These terminating 12tph have a capacity of 1500 x 12tph = 18,000 pax/h. If they terminated at OOC instead, that would handle half the expected load (though many of these would be standing)
• Increasing EL frequency from the current 24tph to its design maximum of 30tph would allow 18tph to terminate at OOC, giving a capacity of 1500 x 18tph = 27,000 pax/h, even if the EL trains arriving from the west are full.

So just using the Elizabeth Line to carry the WCML traffic, you could terminate half the WCML fasts at OOC with super-long trains and easily handle the 589x3x10tph =17,680 pax/h that they could carry.

And some passengers would use the Bakerloo line at Kensal Green, or be heading to Heathow or Reading, or will use the Overground to Richmond or Clapham Jct or West Hampstead instead of the EL. So there would be plenty of slack if needed.

On the other hand, if you really wanted to max out, by terminating all the WCML fasts at OOC with 795m trains, then you would need additional capacity to distribute the passengers onwards. But in that case, the WCML fasts would be available. They could carry a Euston shuttle at 30tph which would have the capacity of a whole new Elizabeth Line in addition to the above (45,000 pax/h).

I know it sounds crazy, but an Elizabeth Line with 30 x 200m trains per hour, with standing, has a capacity more than double that of HS2 with all seated.

 

[The Planner]

You cant run 20tph on the WCML fasts. Presumably MK and Watford don't get any of these trains either?

 

[Nottingham59]

You cant run 20tph on the WCML fasts. Presumably MK and Watford don't get any of these trains either?

How many trains per hour pass MK without stopping? Those would be the best candidates for super-lengthening, leaving other paths on the WCML unchanged.

 

[Wokingham]

im looking forward to seeing the gwr2 plans again, some crayonista maps definitely exist but google draws blank

 

[6Gman]

That's it, exactly. If you're going to split and join trains, then you might as well do it properly and get some significant capacity benefits.


Not at all. If you terminate the long trains at Old Oak Common, you don't have to touch Euston at all. That's £2bn saved on the station and £1.6bn saved on the tunnel from OOC to Euston already. And you don't have to build HS2 phase 1 or phase 2A either


Yes, probably. But this idea is about capacity rather than speed.

Below is what I had in mind for the WCML as an alternative to HS2. But the idea works even better for the GWML.
View attachment 126081
Build a surface station at Old Oak Common, connected to the WCML fast lines, with 10 x 795m platforms. Include platforms to the Elizabeth Line (perhaps two EL stations close together to save walking). The station can also have access to the Bakerloo line at Kensal Green and it would make sense to divert the Overground lines to this station too.

To increase WCML capacity, run three Pendolinos (or their follow-on replacements) connected together as trains 795m long (3x265m), terminating at Old Oak Common. These run non-stop to new "splitting stations" located at:

• Basford Hall (which replaces the current Crewe station) from where separated units can run to Manchester, Liverpool, Preston etc.
• Near Daventry, from where the separated units can run to Birmingham, Trent Valley (and I would add a new line to Wigston for Leicester, Nottingham, Sheffield and Leeds).

These are the numbers:

• HS2 at full capacity can carry 1100 x 17tph = 18,700 pax/h, assuming they are all seated.
• The WCML fasts have a current capacity of 20 x 11-car Pendolinos per hour assuming 3 minute headways = 589 x 20tph = 11,780 pax/h, again assuming all seated.
• Running 795m trains at three minute headways would give a seated capacity of 589x3 x 20tph = 35,340 pax/h. The WCML uplift would be +23,560pax/h which is greater than the capacity of HS2 at its full extent.

How to handle that many passengers at OOC?

• The Elizabeth Line currently has 6tph to Heathrow, 6 tph down the GWML, and 12tph terminating at Paddington. These terminating 12tph have a capacity of 1500 x 12tph = 18,000 pax/h. If they terminated at OOC instead, that would handle half the expected load (though many of these would be standing)
• Increasing EL frequency from the current 24tph to its design maximum of 30tph would allow 18tph to terminate at OOC, giving a capacity of 1500 x 18tph = 27,000 pax/h, even if the EL trains arriving from the west are full.

So just using the Elizabeth Line to carry the WCML traffic, you could terminate half the WCML fasts at OOC with super-long trains and easily handle the 589x3x10tph =17,680 pax/h that they could carry.

And some passengers would use the Bakerloo line at Kensal Green, or be heading to Heathow or Reading, or will use the Overground to Richmond or Clapham Jct or West Hampstead instead of the EL. So there would be plenty of slack if needed.

On the other hand, if you really wanted to max out, by terminating all the WCML fasts at OOC with 795m trains, then you would need additional capacity to distribute the passengers onwards. But in that case, the WCML fasts would be available. They could carry a Euston shuttle at 30tph which would have the capacity of a whole new Elizabeth Line in addition to the above (45,000 pax/h).

I know it sounds crazy, but an Elizabeth Line with 30 x 200m trains per hour, with standing, has a capacity more than double that of HS2 with all seated.

Am I reading this correctly that your scheme would require the obliteration of Kensal Green Cemetery?

 

[RobShipway]

Am I reading this correctly that your scheme would require the obliteration of Kensal Green Cemetery?

It is not the first time that a cemetery has been moved to enable a railway line to be built.

 

[Nottingham59]

Am I reading this correctly that your scheme would require the obliteration of Kensal Green Cemetery?

That's just to illustrate how a super-long WCML terminus could function. If you wanted to preserve green space, an alternative location would have been over the Crossrail depot and where the HS2 station is being built now, which would have allowed the new station to act as an alternative terminus to the WCML, the Chiltern Mainline, and the GWML (to get back on topic).

== == ==
Alternatively, if you didn't want to go for super-long 800m trains, then I suspect the best and cheapest way to add capacity to the GWML would be to dig a twin-track tunnel from Airport Junction to a new surface terminus at Old Oak Common, which would add at least 6tph to capacity and would be much cheaper (10 miles at £100m/km = £1.6Bn) than building a new HS3.

 

[D365]

It is not the first time that a cemetery has been moved to enable a railway line to be built.

And certainly won't be a first for this subforum!

 

[popeter45]

Here's what I would propose for a high speed upgrade to the GWML

upgrade and realign the existing GWML between Paddington and an expanded Bristol parkway for 250km/h or higher rather than a new line

After Bristol parkway a new 250km/h bridge and railway as far as Newport

Then upgrade work to allow 200km/h to Cardiff

Finally a new 200km line to a Swansea low level to replace Swansea station Stuttgart style as a thru line to west wales

 

[6Gman]

It is not the first time that a cemetery has been moved to enable a railway line to be built.

No, but has there been a recent case of an active cemetery being removed?