HS2 rail extension to Leeds set to be scrapped

[Ianno87]

Side-note: Interesting that the apparent news has not had the effect of people celebrating "Stopping HS2". Seems to be very much the opposite - people shouting because they very much want it.

 

[JonathanH]

Side-note: Interesting that the apparent news has not had the effect of people celebrating "Stopping HS2". Seems to be very much the opposite - people shouting because they very much want it.

Isn't that because the bit that the 'anti' campaigners against HS2 didn't / don't want is still being built? They couldn't care less either way about Birmingham to Leeds because it doesn't go through the Chilterns.

 

[Roast Veg]

Side-note: Interesting that the apparent news has not had the effect of people celebrating "Stopping HS2". Seems to be very much the opposite - people shouting because they very much want it.

Nice to have the majority on the side of rail for a change!

 

[Bletchleyite]

With the result that by the 1980s they had to extend the M40 to Birmingham to relieve the M1.

That's a bit like thinking of Chiltern as just a London to Birmingham TOC, rather ignoring all the places in between which the M40 serves.

 

[21C101]

I didn't say there was no benefit to directly solving Welwyn, merely that the benefits are low (basically 2tph on the Fast Line, plus maybe some local extension from Welwyn Garden City) compared to the scale of infrastructure required.

Even if it was only 2PH, suspect it would be nearer 4, 2 extra intercity paths on a line that currently runs 5-8 intercities each way per hour is a significant increase.

Your comment re stoppers at Brookmans Park. Thameslink somehow manages to run their four fasts an hour on the slow lines to Radlett (up) and from Harpenden (down) despite six slow trains as far as St Albans and two/four dependent on time of day to Luton.

I did find your comment about Thameslink being very reliable most amusing, speaking as someone who uses it daily.

That's a bit like thinking of Chiltern as just a London to Birmingham TOC, rather ignoring all the places in between which the M40 serves.

It was built as a London to Oxford London Radial motorway with no intention of extending it further until a big change was made after they realised the M1 couldn't cope.

 

[Shrop]

The proposals are yet to be released, so no one really knows. But certainly the upgrade needs to have complete segregation of fast and slow trains for it to be effective. But that would be a BIG upgrade.

Exactly. You might even think a whole new railway would be a good idea, you could even name it HS2 Eastern Arm ...

== Doublepost prevention - post automatically merged: 16 Nov 2021 ==

Isn't that because the bit that the 'anti' campaigners against HS2 didn't / don't want is still being built? They couldn't care less either way about Birmingham to Leeds because it doesn't go through the Chilterns.

You've hit the nail on the head. Very sad that the bit that was most needed is being shelved while the badly routed London-centric bit is still going ahead.

 

[Ianno87]

Even if it was only 2PH, suspect it would be nearer 4, 2 extra intercity paths on a line that currently runs 5-8 intercities each way per hour is a significant increase.

2tph on (basically) 18tph* across the viaduct today is 11% capacity uplift, in exchange for a £multi-billion investment. 11% doesn't buy very many years' growth at typical pre-Covid growth...

+4tph is not possible, unless (perhaps) closing Welwyn North is accepted.



*Because its capacity is not just for long distance, but the outer Home Counties, Cambridge and Fenland too.

 

[Shrop]

Maybe, wait 2 days until Thursday when we'll (hopefully) find out what the proposals actually are? Once we know that, then it may be possible to answer those questions.

Thanks, I look forward to any update!

 

[ABB125]

It was built as a London to Oxford London Radial motorway with no intention of extending it further until a big change was made after they realiae the M1 couldn't cope.

However, HS2 provides such a huge capacity uplift that it will be decades before we'll need to be thinking about providing more capacity. And then, the simple solution is to build a new east coast route.

 

[21C101]

2tph on (basically) 18tph* across the viaduct today is 11% capacity uplift, in exchange for a £multi-billion investment. 11% doesn't buy very many years growth at typical.pre-Covid growth...

+4tph is not possible, unless (perhaps) closing Welwyn North is accepted.



*Because its capacity is not just for long distance, but the outer Home Counties, Cambridge and Fenland too.

So 18 per hour across the viaduct compared with up to 24 per hour on the LSWR main line fast lines and not much less on the slows on a similar paired formation, despite no hitchin style flyover at Woking.

== Doublepost prevention - post automatically merged: 16 Nov 2021 ==

However, HS2 provides such a huge capacity uplift that it will be decades before we'll need to be thinking about providing more capacity. And then, the simple solution is to build a new east coast route.

Not south of Birmingham which will be basically full up with 17 per hour each way on day 1.

 

[Ianno87]

So 18 per hour across the viaduct compared with up to 24 per hour on the LSWR main line fast lines and not much less on the slows on a similar paired formation, despite no hitchin style flyover at Woking.

Speed is somewhat different though. Because braking distance is proportional to the square of speed, the ECML headway can never match the SWML headway.

 

[21C101]

Speed is somewhat different though. Because braking distance is proportional to the square of speed, the ECML headway can never match the SWML headway.

But with the SWML having about 40 an hour each way on its four tracks without breaking sweat, 18 an hour each way on the four tracks between Stevenage and Hitchin, because there is a three mile stretch of two track in the middle with a station in the middle of that isn't very good whatever the speed difference is (all of 25mph).

 

[ABB125]

Not south of Birmingham which will be basically full up with 17 per hour each way on day 1.

There won't need to be any more trains running - I haven't looked at loading predictions but I doubt a 400m long train will be full on the opening day, even if every passenger from the equivalent existing train transfers to HS2 (simply because there are far more seats on a 400m train compared to a ~250m train). So it will be some time before HS2 trains are full and standing. Then the next step would be to run the trains currently planned for 200m as 400m sets.

Just because the line will be full in timetable terms, doesn't mean it'll be at capacity.

 

[Ianno87]

But with the SWML having about 40 an hour each way on its four tracks without breaking sweat, 18 an hour each way on the four tracks between Stevenage and Hitchin, because there is a three mile stretch of two track in the middle with a station in the middle isn't very good whatever the speed difference is (all of 25mph).

"Isn't very good". I dare you to say that to the people who plan and operate it every day.

You *could* solve Welwyn - but given that almost all trains over it share the same tracks all the way to Finsbury Park, running non-stop one behind the other, the capacity release is minimal.

 

[Killingworth]

A simple tunnel would not be a solution as the situation is much more complex.
The current formation is a cutting with overbridges and cut and cover/shallow tunnels.
The river would not be a problem.

However there are long abandoned tunnels and mines.
The Parkway bridge with the western support above the tunnel you propose.
Tram embankment and modified bridge.
After the current tunnel the formation is double track on viaducts and bridges for over a kilometre beyond.

Between Nunnery and the station a 0.33km widening of the cutting would enable a three track wide formation.
The area near/above is no longer densely built on and at least two overbridges not needed.
Some work would anyway be necessary for electrification

A complete rebuild in some kind of concrete box would probably be cheaper and less complicated.

Rebuild the viaducts in the Don Valley double deck, maybe combination of cutting and double deck out of Sheffield. Blue sky thinking needed, but whatever is even considered isn't going to be cheap - so probably won't happen.

 

[21C101]

You *could* solve Welwyn - but given that almost all trains over it share the same tracks all the way to Finsbury Park, running non-stop one behind the other, the capacity release is minimal.

Currently two stoppers an hour use the fast lines *and* stopnat Welwyn north1getting them off it and replacing them with fasts will free up more than two paths.

And there no good reason that all the TL/GN services using the fast lines would have to continue doing so if you built platforms on the goods lines at Hornsey and Haringey so that the Moorgate to Hertford Loop services don't have to use the slow lines

In fact it would be highly desirable to get more of the TLs south of Welwyn on the slows so the service to Potters Bar, Hatfield and Welwyn could be improved.

Ianno87 wrote "Isn't very good". I dare you to say that to the people who plan and operate it every day.

Don't be silly, the "Isn't very good" is because of the missing bit of four track section.

 

[Ianno87]

Currently two stoppers an hour use the fast lines *and* stopnat Welwyn north1getting them off it and replacing them with fasts will free up more than two paths.

It doesn't because they can join/diverge the two track section at below the "fast" headway to the preceding/following service.

 

[miami]

Side-note: Interesting that the apparent news has not had the effect of people celebrating "Stopping HS2". Seems to be very much the opposite - people shouting because they very much want it.

This government is known for leaking ideas, and then adjusting based on the decision

No doubt party strategists will be looking at how it impacts (especially on 'red wall' seats) before deciding whether to go through with it or not

 

[Ianno87]

This government is known for leaking ideas, and then adjusting based on the decision

Shout out to the people re-typing the IRP report as we speak, if so!

 

[Bald Rick]

Beyond Stevenage for the remainder of the ~200 miles to york there is precisely one tunnel that would need work done on it and six stations without through roads in both directions, one of which most trains stop at anyway.

I’m going to be polite, and suggest you look at the Sectional Appendix, and a map. There are 136 miles of 125mph running on the Down line from Kings Cross to York. Even if all of them could be upgraded to 140mph - they can’t - then allowing for acceleration and deceleration at the various restrictions, it would save 6 minutes.

Going above 125mph is a significant change, in that many standards for the infrastructure and operation change. The incremental cost over renewal is potentially significant, particularly for the track, structures and electrification.

It appears Manchester isn’t getting the underground expansion at Piccadilly the Bechtel Review favored. So it’s not all completely rosy West of Pennines.

The underground option was never going to happen. Lots of extra cost, delay, and no benefit.

It's a bit different from the WCRM, because even if you do nothing else to the existing TP route, it absolutely needs to be electrified. So if you're going to do that and have the related disruption, other stuff is smaller.

Its actually rather similar to WCRM - lots of the track and signalling needs renewal now.

But with the SWML having about 40 an hour each way on its four tracks without breaking sweat, 18 an hour each way on the four tracks between Stevenage and Hitchin, because there is a three mile stretch of two track in the middle with a station in the middle of that isn't very good whatever the speed difference is (all of 25mph).

You’re comparing apples and oranges. The ECML can (and has) run 40 trains an hour each way through Finsbury Park.

Currently two stoppers an hour use the fast lines *and* stopnat Welwyn north1getting them off it and replacing them with fasts will free up more than two paths.

can I see your workings? Where do these extra trains go at London, and where do they go north of Hitchin?

 

[norbitonflyer]

. Very sad that the bit that was most needed is being shelved while the badly routed London-centric bit is still going ahead.

It's been discussed before. I can't now find the article in Modern railways, but as I recall the point was that if the northern parts had been built first, they would never have been able to cover their costs. Capacity is not the main problem in the north, so the new lines would have taken custom away from the existing services between Manchester/Yorkshire and Birmingham (which would have had to continue to operate to serve intermediate locations like Stafford and Chesterfield) If the trains had continued beyond Birmingham towards London, it could only have been by replacing existing services.

There was a reason the first section of the M1 was built from London to the Midlands, and the section on to Yorkshire followed later.

 

[unlevel42]

Rebuild the viaducts in the Don Valley double deck, maybe combination of cutting and double deck out of Sheffield. Blue sky thinking needed, but whatever is even considered isn't going to be cheap - so probably won't happen.

Hmm.
Maybe, just maybe.
From Darnall onto the double decking above the cutting with the top deck using the current supertram platforms(northend)? The south end for arriving London trains which would then continue to Beighton and Chesterfield and back to London
Supertram redirected through the bus interchange or Moorfoot and the underused Arundel Gate?
Would the Parkway bridge would be in the way?
No insomnia tonight.

 

[21C101]

I’m going to be polite, and suggest you look at the Sectional Appendix, and a map. There are 136 miles of 125mph running on the Down line from Kings Cross to York. Even if all of them could be upgraded to 140mph - they can’t - then allowing for acceleration and deceleration at the various restrictions, it would save 6 minutes.

Going above 125mph is a significant change, in that many standards for the infrastructure and operation change. The incremental cost over renewal is potentially significant, particularly for the track, structures and electrification.

You assume firstly that the maximum speed wont go above 140mph and secondly that nothing will be done to remove any of the restrictons (such as the flat crossing at Newark)

I didn't say that replacing to a higher standard during renewals was zero cost but it is far more cost effective than doing it out of course

 

[DynamicSpirit]

I think the fundamental problem with all that is that sorting out Welwyn would be a colossally expensive operation, totalling £many billions. If you're going to spend that much money, you'd better be getting absolutely huge benefits from it. HS2 kinda meets that criteria: £100Bn is extraordinarily expensive, but we can kinda justify it because it gives you an extraordinarily huge capacity uplift covering a large number of towns and cities (as well as speed benefits). 4-tracking the Welwyn viaduct etc. would also be extremely expensive - and yes, in an ideal World with limitless funding, we'd do it - because - it would give some new capacity, and make timetabling the ECML a lot easier and more flexible. But in the real World, it wouldn't give you anything like enough to justify the cost.

 

[MontyP]

I’m going to be polite, and suggest you look at the Sectional Appendix, and a map. There are 136 miles of 125mph running on the Down line from Kings Cross to York. Even if all of them could be upgraded to 140mph - they can’t - then allowing for acceleration and deceleration at the various restrictions, it would save 6 minutes.

Going above 125mph is a significant change, in that many standards for the infrastructure and operation change. The incremental cost over renewal is potentially significant, particularly for the track, structures and electrification.




The underground option was never going to happen. Lots of extra cost, delay, and no benefit.




Its actually rather similar to WCRM - lots of the track and signalling needs renewal now.




You’re comparing apples and oranges. The ECML can (and has) run 40 trains an hour each way through Finsbury Park.



can I see your workings? Where do these extra trains go at London, and where do they go north of Hitchin?

To us amateurs it doesn't seem to make any sense - the ECML is constrained to 18 tph in each direction, and for years I've understand that this is (largely) due to Welwyn viaduct (as well as other things such as Newark flat crossing, 2 track sections north of Huntingdon etc). So now the view is that relieving the bottleneck would only allow 2 extra trains per hour to run, so 20 tph on a 4 track railway? What else would need to be done to enable (say) 10 fast trains to run as far as Peterborough with another 4-6 branching off at Hitchin towards Cambridge?

Out of interest what is the capacity on the 4-track WCML south of MKC?

 

[Bletchleyite]

To us amateurs it doesn't seem to make any sense - the ECML is constrained to 18 tph in each direction, and for years I've understand that this is (largely) due to Welwyn viaduct (as well as other things such as Newark flat crossing, 2 track sections north of Huntingdon etc). So now the view is that relieving the bottleneck would only allow 2 extra trains per hour to run, so 20 tph on a 4 track railway? What else would need to be done to enable (say) 10 fast trains to run as far as Peterborough with another 4-6 branching off at Hitchin towards Cambridge?

Out of interest what is the capacity on the 4-track WCML south of MKC?

The daytime service pre COVID was 9 ICs (3 Brum, 3 Manc, one Scotland, one Liverpool and one Chester), 7 LMs (3 Brum, 2 Tring, one MKC, one Crewe) and the Southern, total 17. But there were a number of off pattern peak extras, a spare path the open access mob were going to use and a freight, so it is a bit hard to say, but I guess it is somewhere around 20-22 or so.

 

[JonathanH]

What else would need to be done to enable (say) 10 fast trains to run as far as Peterborough with another 4-6 branching off at Hitchin towards Cambridge?

Where are 10 fast trains an hour from Kings Cross to Peterborough going to go to and how are they going to be platformed at Kings Cross itself?

At the very least a change of timetabling rules at Kings Cross would be needed to have much shorter turnarounds.

 

[tbtc]

To us amateurs it doesn't seem to make any sense - the ECML is constrained to 18 tph in each direction, and for years I've understand that this is (largely) due to Welwyn viaduct (as well as other things such as Newark flat crossing, 2 track sections north of Huntingdon etc). So now the view is that relieving the bottleneck would only allow 2 extra trains per hour to run, so 20 tph on a 4 track railway? What else would need to be done to enable (say) 10 fast trains to run as far as Peterborough with another 4-6 branching off at Hitchin towards Cambridge?

Im an amateur myself, but the ECML is effectively two track from Huntingdon to Peterborough and then from Stoke Tunnel to Colton Junction (and again north of Northallerton), so even if you extended the four track section a little at Welwyn, you're just going to hit the next bottleneck (and that's assuming that you can find platforms at the Cross - as @JonathanH says)

(yes, it's three track for sections, but three tracks are essentially just one track in one direction - you're not going to be running significantly more northbound trains than southbound ones, after all, it all needs to balance up)

And, with no "local" trains on the line north of Peterborough, you're going to have some trains stopping at small places like Retford, which eats into capacity a bit

 

[21C101]

I think the fundamental problem with all that is that sorting out Welwyn would be a colossally expensive operation, totalling £many billions. If you're going to spend that much money, you'd better be getting absolutely huge benefits from it. HS2 kinda meets that criteria: £100Bn is extraordinarily expensive, but we can kinda justify it because it gives you an extraordinarily huge capacity uplift covering a large number of towns and cities (as well as speed benefits). 4-tracking the Welwyn viaduct etc. would also be extremely expensive - and yes, in an ideal World with limitless funding, we'd do it - because - it would give some new capacity, and make timetabling the ECML a lot easier and more flexible. But in the real World, it wouldn't give you anything like enough to justify the cost.

I fear you might be right. To be a reasonable cost it needs to be online widening othrwise you need about five miles or more of new line and flying junctions either end but the chances of that being done from either the way things are done these days on the railways or a nimby point of view are remote.

Not much point doing things like the Newark crossing unless it is done though.

 

[sjm77]

I would have thought the easiest way to fix the Welwyn bottleneck was to build a tunnel for the fast lines. Yes, it would have to dive under the Mimram Valley. The viaduct is 30metres high, so to pass under the valley floor would require a drop and rise of a bit more than that. Welwyn Garden City station and Woolmer Green (the end of the two-track section) are both about 3km from the middle of the valley, so gradients of about 1 in 100 (30/3000) would be needed - well within the capabilities of anything that uses the fast lines on the ECML. How much would a 6km double track tunnel cost?

2tph on (basically) 18tph* across the viaduct today is 11% capacity uplift, in exchange for a £multi-billion investment. 11% doesn't buy very many years' growth at typical pre-Covid growth...

+4tph is not possible, unless (perhaps) closing Welwyn North is accepted.

It is not Welwyn North that would need closing to maximise extra paths should a new viaduct ever be built. The limiting factor would be Fast Line Capacity between Alex Palace and Welwyn Garden city. Sure, with the suburban stoppers running every 15 minutes during the peak it could be possible to offload 4 tph onto the slow line between Potters Bar and Welwyn Garden city, but at 3 minute headways only 20 tph is possible on the fast lines south of there. This would probably depend on moving the Moorgate service to the outer most lines with new Platform faces at Hornsey and Harringey. It might also mean only timetabling the Northbound Intercity services at 100mph South of Potters Bar to match the speed of the Thameslink services [Southbound line speed is only 100mph anyway].

But with the SWML having about 40 an hour each way on its four tracks without breaking sweat, 18 an hour each way on the four tracks between Stevenage and Hitchin, because there is a three mile stretch of two track in the middle with a station in the middle of that isn't very good whatever the speed difference is (all of 25mph).

This is because the majority of slow line services call all stations so 3 minute headways are feasible on both slow and fast lines. For this section of the ECML this is neither warranted nor appropriate