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Is the eastern arm of HS2 needed?

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Grimsby town

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So I'm playing devils advocate here but time wise, at least after the 800/1's are delivered, there won't be a great deal of improvement between HS2 and the ECML. Now I know HS2 is about capacity but it seems to me that capacity could be significantly boosted without spending around £16 billion pound on an eastern arm.

First CrossCountry services can easily be expanded to cope with demand. Most local services around Leeds and Sheffield have room for extra carriages as well.

As for the ECML, south of York there are around 4 major bottlenecks. Doncaster, Newark, the Peterborough area and Welwyn. Doncaster could be solved by creating a diversion to the east of Doncaster from Temple Hurst junction to just north of Bawtry with a station at Doncaster Sheffield Airport. Newark could be solved by a simple flyover and Peterborough with a flyover to the north of the station and four tracking to Huntingdon. Welwyn would be the most difficult to solve but the closure of Welwyn North could be a start.

All of this should cost no more than £5 billion with the rest of the money being spent on construct new lines in strategic places in the north and providing vastly improved inner city transport network (S Bahn style tunnels, tram-trains and networks, Bus Rapid Transit and improved walking and cycling).
 
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NotATrainspott

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So I'm playing devils advocate here but time wise, at least after the 800/1's are delivered, there won't be a great deal of improvement between HS2 and the ECML. Now I know HS2 is about capacity but it seems to me that capacity could be significantly boosted without spending around £16 billion pound on an eastern arm.

First CrossCountry services can easily be expanded to cope with demand. Most local services around Leeds and Sheffield have room for extra carriages as well.

As for the ECML, south of York there are around 4 major bottlenecks. Doncaster, Newark, the Peterborough area and Welwyn. Doncaster could be solved by creating a diversion to the east of Doncaster from Temple Hurst junction to just north of Bawtry with a station at Doncaster Sheffield Airport. Newark could be solved by a simple flyover and Peterborough with a flyover to the north of the station and four tracking to Huntingdon. Welwyn would be the most difficult to solve but the closure of Welwyn North could be a start.

All of this should cost no more than £5 billion with the rest of the money being spent on construct new lines in strategic places in the north and providing vastly improved inner city transport network (S Bahn style tunnels, tram-trains and networks, Bus Rapid Transit and improved walking and cycling).


CrossCountry services can indeed be physically extended for more capacity but the financial case to do so isn't necessarily enough. Those extra carriages are expensive because they need to be able to run at fast mainline speeds without electrification, while a good proportion of the demand on the services is short-distance hops. The solution would actually be to run extra regional trains to soak up these shorter-distance travellers, leaving the more expensive InterCity sets for longer-distance travellers. However, that's not possible due to track and station capacity constraints, meaning that the CrossCountry services have to be a jack of all trades while mastering none. HS2 helps to solve this by removing some of the longer-distance travellers and allowing the paths to be used by more appropriate trains.

The law of diminishing returns means that each solved bottleneck results in less and less extra capacity being provided. Why? Because naturally you build the most promising schemes first. As more are built, the ones remaining are less and less promising. Network Rail are already looking at solving some of your listed bottlenecks even with HS2 being planned - Peterborough is getting the Werrington Diveunder. Bypassing Doncaster like that is highly unlikely to provide good value for money. Welwyn is a much harder nut to crack than you think. NR have said that without HS2, they would not just need to four-track the viaduct and North station but actually build a brand new quasi-HSR line from Alexandra Palace to Biggleswade.

A key reason for the eastern arm of HS2 is that the Birmingham-London line will be capable of 18 trains an hour but there's not enough demand along the WCML corridor alone to fill that right now. Without the eastern arm, there would be significant under-use of the infrastructure, bringing down the business case for the whole scheme. The eastern arm ensures that the Phase 1 line gets filled while also solving a good number of other issues, even if the journey time reductions it causes aren't really that dramatic.
 

Grimsby town

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CrossCountry services can indeed be physically extended for more capacity but the financial case to do so isn't necessarily enough. Those extra carriages are expensive because they need to be able to run at fast mainline speeds without electrification, while a good proportion of the demand on the services is short-distance hops. The solution would actually be to run extra regional trains to soak up these shorter-distance travellers, leaving the more expensive InterCity sets for longer-distance travellers. However, that's not possible due to track and station capacity constraints, meaning that the CrossCountry services have to be a jack of all trades while mastering none. HS2 helps to solve this by removing some of the longer-distance travellers and allowing the paths to be used by more appropriate trains.

The law of diminishing returns means that each solved bottleneck results in less and less extra capacity being provided. Why? Because naturally you build the most promising schemes first. As more are built, the ones remaining are less and less promising. Network Rail are already looking at solving some of your listed bottlenecks even with HS2 being planned - Peterborough is getting the Werrington Diveunder. Bypassing Doncaster like that is highly unlikely to provide good value for money. Welwyn is a much harder nut to crack than you think. NR have said that without HS2, they would not just need to four-track the viaduct and North station but actually build a brand new quasi-HSR line from Alexandra Palace to Biggleswade.

A key reason for the eastern arm of HS2 is that the Birmingham-London line will be capable of 18 trains an hour but there's not enough demand along the WCML corridor alone to fill that right now. Without the eastern arm, there would be significant under-use of the infrastructure, bringing down the business case for the whole scheme. The eastern arm ensures that the Phase 1 line gets filled while also solving a good number of other issues, even if the journey time reductions it causes aren't really that dramatic.

True with regard to CrossCountry gaining capacity and being able to run with more suitable commuter style stock but with electrification there's nothing stopping these being run by something like the new TPE CAF EMU's which will be more suitable that voyagers.

As for a Doncaster bypass, this could easily save 5 minutes and bring east coast journey times closer to that of HS2. If a business case can be found for HS2 I imagine one that saved 5 minutes for each intercity train costing significantly less could easily be viable. After all cost benefit analysis is weighted heavily in favour of travel time savings. There plans to expand Doncaster Airport and build a station there so this would also improve journey times from York, Newcastle and Leeds to the airport.

With Welwyn, I specifically never mentioned for tracking because I realise there is significant difficulty to achieve this. This perhaps limits what I have proposed above.

Yes the business case for Phase 1 relies on eastern traffic but it wouldn't surprise me if it was curtailed to save money while still building the first phase of HS2
 

NotATrainspott

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True with regard to CrossCountry gaining capacity and being able to run with more suitable commuter style stock but with electrification there's nothing stopping these being run by something like the new TPE CAF EMU's which will be more suitable that voyagers.

Unfortunately the busiest sections are the non-electrified ones. While the solution to almost every problem is indeed electrification, at this rate we'll be lucky to see big chunks of the XC network wired up by the time that Phase 1 opens.

As for a Doncaster bypass, this could easily save 5 minutes and bring east coast journey times closer to that of HS2. If a business case can be found for HS2 I imagine one that saved 5 minutes for each intercity train costing significantly less could easily be viable. After all cost benefit analysis is weighted heavily in favour of travel time savings. There plans to expand Doncaster Airport and build a station there so this would also improve journey times from York, Newcastle and Leeds to the airport.

A station at Doncaster Airport is incompatible with the idea of building a bypass for journey time savings. If you're trying to save time, then you're not going to stop trains there. The only trains worth diverting by this bypass are non-stop ones, as the existing Doncaster station is a useful rail hub. Therefore, it's a complete non-starter.

Please also remember that cheaper does not mean more worthwhile. The UK Government has effectively unlimited ability to borrow money to fund infrastructure schemes. The main constraint is finding schemes which are actually worth building, and having the non-financial resources to build them.

With Welwyn, I specifically never mentioned for tracking because I realise there is significant difficulty to achieve this. This perhaps limits what I have proposed above.

Yes the business case for Phase 1 relies on eastern traffic but it wouldn't surprise me if it was curtailed to save money while still building the first phase of HS2

Again, penny wise but pound foolish is the problem with these ideas. Saving money on a micro level can mean disproportionate reductions in the benefits had from spending any money at all. The challenge is finding the optimum balance where minor cuts don't cause these reductions. For instance, much of the eastern arm is limited to 360km/h rather than the normal 400km/h of the southern and western bits. Spending lots of money on increasing that to 400km/h would have very few benefits, but saving a bit more money by reducing it further would mean a greater reduction in benefits. The 360km/h speed is at the global maxima of the cost/benefit curve.
 

AndrewE

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It might provide some much-needed extra capacity between Leeds and Manchester / Liverpool if you changed at Brum - and might be quicker too!
 

The Ham

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The thing that has to be remembered is that the Eastern arm isn't due to open for about 15 years, as such passenger demand for be fairly different from now.

At 2.5% growth per year that's 45% more passengers (XC just to stand still would need 6 or 8 coach trains rather than today's 4 or 5).

However, if growth hits 4% that's 80% more passengers (XC would need 8 or 9 coach trains). That could also mean that EC would need nearly double the number of seats that they currently have.

Then there's the problem of what do you do on the following years, in that in 20 years time there is likely to be more demand than in 15.

However, chances are if existing TOC's provided more capacity that it would encourage a faster rate of growth.

Also, it needs to be remembered that the eastern arm will significantly reduce journey times, which will further increase demand.

Even if there was scope to reduce existing journey times to choose to that of HS2 there isn't the score to improve capacity by enough. It is one of the reasons that I have often said that we'll need some of the other options (works package 2) for capacity in advance of HS2 opening.

It also has to be remembered that by removing trains from the ECML that more commuter services could be run. This could include services for London as well as other towns and cities along the route.
 

Ianno87

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Re: Welwyn. Closing the station but retaining 2 tracks would only create 2-4 paths per hour tops (plain line two track capacity would be no more than 20tph), which limits the value of grand interventions further north.

To *really* solve Welwyn (other than HS2) would need effective 4 tracking this section. Widening the current alignment (viaduct + 2 tunnels + station) is probably a virtual non-starter as I would wager it would be almost unbuildable.

So you probably need a two-track cutoff type alignment bridging the Welwyn area, which would in effect be a new section of High Speed railway from (at least) south of Hatfield to (at least) north of Hitchin. So cost-wise you've just effectively moved part of HS2 somewhere else instead.

Then there's the next constraint of King's Cross platform capacity to resolve next. Good luck with that one (whilst looking longingly at the platform capacity created nearby at Euston by HS2...)
 

NotATrainspott

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Euston platform capacity is another interesting one. The new phased plan involves building six new HS2 platforms to the west of the existing station, which will be enough for the Phase 1 service. Without the eastern arm, there wouldn't be much of a need to provide extra ones. However, upon Phase 1 opening platform requirements for the WCML station will drop significantly, as the remaining services will not require as much servicing or dwell times. If the station is to be rebuilt anyway to allow over-site development and to improve the environment, then there would be really minimal savings involved in not building another set of HS2 platforms. The only real difference between rebuilt WCML and new HS2 platforms is that the latter will be slightly higher (step-free access on HS2 is now confirmed) and slightly further away from the rail head. All of the other services, e.g. escalators and platform furniture, would be exactly the same.
 

Grimsby town

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A station at Doncaster Airport is incompatible with the idea of building a bypass for journey time savings. If you're trying to save time, then you're not going to stop trains there. The only trains worth diverting by this bypass are non-stop ones, as the existing Doncaster station is a useful rail hub. Therefore, it's a complete non-starter.

Well it's not really. It would provide a quicker more, direct route than Doncaster by providing higher line speeds and being shorter in length. There are proposals to bypass York, which is far busier and have a parkway station so if it can be done at York it can be done at Doncaster. As for connectivity, Doncaster only really provides interchange for Grimsby, Scunthorpe and Goole along with a few smaller places such as Thorne. The 2 hourly Leeds via Wakefield would still have to run via Doncaster as would CrossCountry and interchange can be provided by running services to a new Doncaster Airport station. Doncaster is already a serious bottleneck I hate to see what it will become after the improved service frequency.
 

Grimsby town

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Re: Welwyn. Closing the station but retaining 2 tracks would only create 2-4 paths per hour tops (plain line two track capacity would be no more than 20tph), which limits the value of grand interventions further north.

To *really* solve Welwyn (other than HS2) would need effective 4 tracking this section. Widening the current alignment (viaduct + 2 tunnels + station) is probably a virtual non-starter as I would wager it would be almost unbuildable.

So you probably need a two-track cutoff type alignment bridging the Welwyn area, which would in effect be a new section of High Speed railway from (at least) south of Hatfield to (at least) north of Hitchin. So cost-wise you've just effectively moved part of HS2 somewhere else instead.

Then there's the next constraint of King's Cross platform capacity to resolve next. Good luck with that one (whilst looking longingly at the platform capacity created nearby at Euston by HS2...)

Kings cross has 8 large platforms and 3 smaller platforms. That should be more than enough to provide at least 12 services per hour which is pretty similar to what HS2 plan to run from London to the East.
 

Class 170101

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Kings cross has 8 large platforms and 3 smaller platforms. That should be more than enough to provide at least 12 services per hour which is pretty similar to what HS2 plan to run from London to the East.

9 long platforms actually.

Arguably Hull Trains, Grand Central and the remaining GTR services can use the shorter platforms however in the High peak HT and GC aren't there and GTR run 12 carriage trains which don't fit in the shorter platforms.
 

edwin_m

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9 long platforms actually.

Arguably Hull Trains, Grand Central and the remaining GTR services can use the shorter platforms however in the High peak HT and GC aren't there and GTR run 12 carriage trains which don't fit in the shorter platforms.

The "long" platforms at Kings Cross are only long enough for a single HS2 set and couldn't be extended without digging the tunnels out into a huge trench. Whereas Euston has much longer platforms to start with so creating a station to hold pairs of HS2 units is relatively speaking less difficult. So even if Kings Cross and the existing ECML fast lines could take as many trains per hour as HS2, the passenger capacity would still only be half.
 

MarkyT

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The "long" platforms at Kings Cross are only long enough for a single HS2 set and couldn't be extended without digging the tunnels out into a huge trench.

The Grand Union Canal passes over Gasworks tunnels near the south end portals. Clearance to the bottom of the basin above is so tight that the tunnels and tracks have a pronounced dip at that end, not compatible with extended platforms or relocated throat junctions in such a trench which would have to pass under a new aquaduct structure without any reduction in the draft of the channel. I can't see permanent closure of the canal as a through route would be realistic either!

https://www.flickr.com/photos/jelltecks/7705085966
 

edwin_m

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The Grand Union Canal passes over Gasworks tunnels near the south end portals. Clearance to the bottom of the basin above is so tight that the tunnels and tracks have a pronounced dip at that end, not compatible with extended platforms or relocated throat junctions in such a trench which would have to pass under a new aquaduct structure without any reduction in the draft of the channel. I can't see permanent closure of the canal as a through route would be realistic either!

https://www.flickr.com/photos/jelltecks/7705085966

OK, make that a huge trench with Falkirk wheels on either side...
 

AndrewE

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The Grand Union Canal passes over Gasworks tunnels near the south end portals. Clearance to the bottom of the basin above is so tight that the tunnels and tracks have a pronounced dip at that end, not compatible with extended platforms or relocated throat junctions in such a trench which would have to pass under a new aquaduct structure without any reduction in the draft of the channel. I can't see permanent closure of the canal as a through route would be realistic either!

https://www.flickr.com/photos/jelltecks/7705085966

Given that I guess it is still the original Victorian infrastructure, I wonder whether there has been any work done on the options for the upgrade that would be necessary? Redesigning the canal to be a shallower (thin bottomed) trough would be easy enough as it's probably a significant depth of puddled clay at the moment. However it is pretty wide there at the moment, which would make it a lot more difficult...

Of course it won't just be the canal crossing but the "approach ramps" too. The level of the underside of the buildings North of the canal might rule it out, but when money is thrown at road projects to ease congestion all over the country I don't see why we shouldn't ask if rail improvements might be feasable - or more accurately, how they could be done.

Likewise, when you see how HS1 was fitted in over the ECML I am sure that you could point the engineers at the Welwyn tunnel job and say "Just do it!"

p.s. just found this: http://londoncanals.uk/2010/02/03/regents-kings-cross-to-actons-lock/ which says the canal had to be put in a cast iron trough in the first place, so there may be no option other than to accept the status quo, as a pair of locks and pumping water back up to the short raised pound wouldn't really be a goer.
 
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RobinW

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I support the principle of the HSF network but this needs to be expanded into a high speed network with at least 2 North South links with suitable points to cross to the other line through connecting services as we must not rely on one line. If we only have one line we risk the same problems we see on the roads when infrastructure is closed commonly called a standstill. We have to be able to connect North to South to ensure we promote the incredible skills and entrepreneurial spirit of the people in the North and Scotland we must ensure there are good routes of access and if there is an eastern arm of HSF2 that could link with an East Coast HSF then brilliant as those points of connectivity could promote service recovery if there are engineeering or other issues on one line.

I will go further that HSF has been England dominated and I support the extending of it into Scotland, also consideration for spurs into North Wales whilst we also look at options to areas like Portsmouth, Southampton and Bournemouth as well as a great Western line to the SW and into South Wales.

These lines however must not replace the existing lines where I feel we have potential to improve freight by rail services as well as local commuter services.
 

edwin_m

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I support the principle of the HSF network but this needs to be expanded into a high speed network with at least 2 North South links with suitable points to cross to the other line through connecting services as we must not rely on one line. If we only have one line we risk the same problems we see on the roads when infrastructure is closed commonly called a standstill. We have to be able to connect North to South to ensure we promote the incredible skills and entrepreneurial spirit of the people in the North and Scotland we must ensure there are good routes of access and if there is an eastern arm of HSF2 that could link with an East Coast HSF then brilliant as those points of connectivity could promote service recovery if there are engineeering or other issues on one line.

I will go further that HSF has been England dominated and I support the extending of it into Scotland, also consideration for spurs into North Wales whilst we also look at options to areas like Portsmouth, Southampton and Bournemouth as well as a great Western line to the SW and into South Wales.

These lines however must not replace the existing lines where I feel we have potential to improve freight by rail services as well as local commuter services.

To some extent your last sentence answers the first part of your post. If major work is needed that closes the high speed lines, the existing lines will still be available to provide some sort of service. As the initial fleet will be able to run on the existing lines, it is even possible that they could be diverted via the WCML to/from Euston.

However, if two new lines were built , then they could not act as diversionary routes for each other unless each one was only 50% utilised in the first place. So in effect it would be spending twice as much to provide a measure of resilience that would only be needed a couple of times a year at most. Experience in other countries shows that purpose-built HS lines are highly reliable.

The two tracks of the high speed routes will also have bi-directional running so if one track has to be closed the route will not be totally blocked. This will almost certainly only be used to rescue stranded trains, not to continue a service when only one track is open.
 

quantinghome

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Without the Eastern Arm you have:

- Incremental improvement to capacity and train frequency.
- Increasingly congested ECML and XC routes, with only very expensive upgrade options available beyond those currently planned.
- Slow transfer through central London to access Heathrow.
- Trains limited to current length and single deck.
- Inherent compromises in service on a mixed use railway.

With Eastern Arm you have:

- 1 hour off Leeds-Birmingham journey time.
- 1 hour off Leeds-Nottingham journey time.
- 40 minutes off Leeds-London journey time.
- Vastly improved access to Heathrow, West London and Thames Valley area via OOC.
- Gauge to allow double decker trains double the current length.
- Relatively easy reconfiguration of ECML to give frequent London service from Lincolnshire and East Yorks as well as improved commuter services.
 
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