Plan for cheaper HS2 Northern leg unveiled

[eldomtom2]

I very much doubt that slab track is going to meaningfully change the cost of a project like this.

I think they have just sliced literally everything they can off the budget to get the headline figure as low as possible, knowing they can always upsell later.

EDIT:
Additionally, reducing the loading gauge to ensure that double deck trains can never be used would be akin to surrendering ~30% of capacity potential, forever.
I am also very skeptical that doing this would save any money - unless they are planning to simply not change any of the structures and use the extra height for the ballast.

Double-decker HSR trains are not very popular worldwide, and in some cases like Japan have been introduced and later withdrawn with no plans for replacement, so I'm not sure "no double-decker trains" is that much of a disadvantage.

 

[HSTEd]

Double-decker HSR trains are not very popular worldwide, and in some cases like Japan have been introduced and later withdrawn with no plans for replacement, so I'm not sure "no double-decker trains" is that much of a disadvantage.

The Japanese trains were withdrawn within the specific demographic context of Japan (the commuter services which they were used on are far less popular than they once were), and aren't really representative of the situation in the UK.

I think the global trend is probably towards more double decekr trains overall, however. In any case, the UK loading gauge already leads to incredibly cramped train interiors, especially with desperate attempts to pack in ever more seating.

 

[fishwomp]

EDIT:
Additionally, reducing the loading gauge to ensure that double deck trains can never be used would be akin to surrendering ~30% of capacity potential, forever.

Bigger tunnels are not cheaper tunnels...

 

[HSTEd]

Bigger tunnels are not cheaper tunnels...

Tunnel size on high speed rail is set almost entirely by aerodynamic factors, not by loading gauge directly.

It is also well known that HS2 has deviated drastically from international practice, desiring small diameter tunnels. This has resulted in the requirement for enormous tunnel entrance galleries unlike anything found elsewhere (as well as extremely complex ventilation systems and complicated evacuation procedures), and it is highly questionable whether any of this is cheaper than simply doing what everyone else is doing and building bigger tunnels.

The cost of tunnels is, according to studies on the topic, roughly linear with diameter - which means tunnel costs scale with the square root of cross section.
Marginally increasing cross section of the tunnel to account for a larger train cross section will have negligible effect on project costs.

 

[Richard123]

I am trying to recall what the actual cost of phase 2A and 2B was, without the Manchester tunnel. I seem to recall it was very small compared with the cost of the Southern section, which maybe be more built up. On the news the mayors talk of billions of £ growth per year. Makes the actual cost look small. I guess the return on that growth, has to find it's way to pay for the line in the first place.. The moment people think it is not their tax or pothole repairs paying for it, you make progress.. The reason for the line really should have been clearly explained at the start. Instead we got "saves Boris and his mates 20 minutes to Birmingham". Did he ever go by train to Birmingham?

I don't know, but a major driver of cost was the willingness to redesign to the whims of his donors. Quite a few of those lived in the Chilterns, and didn't want to see a railway (even if was in a cutting a kilometer from their mansion), hence the staggeringly large amount of tunnel and civil engineering cost.

There was also a generous compensation scheme based on property value which made many rich landowners even rich, while refusing to help many of those in inner-city areas which were judged to be "already undesirable" and therefore unworthy of compensation.

It was a railway project with substantial political involvement.

 

[Backroom_boy]

So it's basically 2A;
* slightly de-specced (ballested track, 'standard loading gauge)
* contractors not having to worry about the total cost of ownership
* broken up into bite sized chunks
* existing spend not included in the price
* rebranded
* expensive bits left vague for future stages

I think this is probably the route forward

 

[LLivery]

I do feel like smaller loading gauge is a mistake. If we're building HS2 so far as one gauge, that should be continued. We never needed more than 320km/h, even if 350km/h+ becomes normal. The 'future proofing for advancements in tech' was always bizarre because of the size of the UK, let alone the increased energy consequences.

Nothing wrong with thinking big, but like government, we need to plan and propose with the imperfect world (or fiscal situation) we have, not what we'd like in theory. And that means not overdoing it with gold plating, ultra fast linespeed and slab track; yes it's cheaper in the long run but, how much of the HSR system in the rest of Europe uses it? It feels like we hate copying the rest of Europe, but when we do (HS1) it flipping works.

Tunnel size on high speed rail is set almost entirely by aerodynamic factors, not by loading gauge directly.

It is also well known that HS2 has deviated drastically from international practice, desiring small diameter tunnels. This has resulted in the requirement for enormous tunnel entrance galleries unlike anything found elsewhere (as well as extremely complex ventilation systems and complicated evacuation procedures), and it is highly questionable whether any of this is cheaper than simply doing what everyone else is doing and building bigger tunnels.

The cost of tunnels is, according to studies on the topic, roughly linear with diameter - which means tunnel costs scale with the square root of cross section.
Marginally increasing cross section of the tunnel to account for a larger train cross section will have negligible effect on project costs.

Something I've wondered for a while is why do we in the UK tend to do twin bore rather than single in rail projects these days? Sounds like these smaller diameter twin bores aren't any better financially than just doing a single bore? But, there is of course a safety benefit.

 

[Manutd1999]

So it's basically 2A;
* slightly de-specced (ballested track, 'standard loading gauge)
* contractors not having to worry about the total cost of ownership
* broken up into bite sized chunks
* existing spend not included in the price
* rebranded
* expensive bits left vague for future stages

I think this is probably the route forward

So essentially how HS2 should have been done in the first place...

 

[HSTEd]

Something I've wondered for a while is why do we in the UK tend to do twin bore rather than single in rail projects these days? Sounds like these smaller diameter twin bores aren't any better financially than just doing a single bore? But, there is of course a safety benefit.

I believe twin bore tunnels in Europe are relatively common because it is the conceptually "simplest" way to meet fire safety and evacuation requirements.

Two tunnel bores with cross passages so that people can take refuge in the other bore if a fire or other incident happens.
Doing this with a single door bore requires more design work and regulatory effort than just buying another tunnel boring machine.

 

[Doctor Fegg]

I don't know, but a major driver of cost was the willingness to redesign to the whims of his donors. Quite a few of those lived in the Chilterns, and didn't want to see a railway (even if was in a cutting a kilometer from their mansion), hence the staggeringly large amount of tunnel and civil engineering cost.

There was also a generous compensation scheme based on property value which made many rich landowners even rich, while refusing to help many of those in inner-city areas which were judged to be "already undesirable" and therefore unworthy of compensation.

It was a railway project with substantial political involvement.

In much the same way as Shirley Porter was personally surcharged £12m for taking political decisions for electoral gain, I wish we could do the same to Rishi Sunak over the money he lost the country with his endless pratting about over HS2. It's not like he can't afford it...

 

[Backroom_boy]

In much the same way as Shirley Porter was personally surcharged £12m for taking political decisions for electoral gain, I wish we could do the same to Rishi Sunak over the money he lost the country with his endless pratting about over HS2. It's not like he can't afford it...

Yeah the only slight sympathy I have for SP is that local politicians are seemingly held to a higher standard than our national ones

 

[snowball]

So it's basically 2A;
* slightly de-specced (ballested track, 'standard loading gauge)
* contractors not having to worry about the total cost of ownership
* broken up into bite sized chunks
* existing spend not included in the price
* rebranded
* expensive bits left vague for future stages

I think this is probably the route forward

It also includes a major part of 2B, minus the Crewe tunnel (a big de-speccing) and minus the part that is common with NPR (already made part of NPR by the government).

Also I must have missed where it says anything about bite-sized chunks. Doesn't it just have one chunk for 2A and another for what remains of 2B? These were already well separated from each other, with 2A having been through parliament and ready to go, and 2B years away.

 

[Backroom_boy]

It also includes a major part of 2B, minus the Crewe tunnel (a big de-speccing) and minus the part that is common with NPR (already made part of NPR by the government).

Also I must have missed where it says anything about bite-sized chunks. Doesn't it just have one chunk for 2A and another for what remains of 2B? These were already well separated from each other, with 2A having been through parliament and ready to go, and 2B years away.

Ah my mistake about the bite-size bits. Hadn't fully appreciated the Northern chunk was actually half of 2B. But branding the chunks with geographical names is a good idea to 'keep it local'

 

[Snow1964]

I believe twin bore tunnels in Europe are relatively common because it is the conceptually "simplest" way to meet fire safety and evacuation requirements.

Two tunnel bores with cross passages so that people can take refuge in the other bore if a fire or other incident happens.
Doing this with a single door bore requires more design work and regulatory effort than just buying another tunnel boring machine.

Actually it not that difficult to add a vertical concrete wall as a separation in a large tunnel, especially if after the TBM has passed need to add a concrete floor base so will be adding a reinforced concrete structure anyway, it is inverted T shape

I don't think anything tall can be slip paved, but it is possible to have wall sections on wheels that after casting a length, are moved forward ready to do next part.

Of course cut and cover and immersed tube tunnels are often built like that anyway, one trench with a structure consisting of two or more separate tunnels either side of dividing walls.

 

[eldomtom2]

It also includes a major part of 2B, minus the Crewe tunnel (a big de-speccing) and minus the part that is common with NPR (already made part of NPR by the government).

Doesn't it not explicitly say "no Crewe tunnel"?

 

[MidlandMainlie]

Tunnel size on high speed rail is set almost entirely by aerodynamic factors, not by loading gauge directly.

It is also well known that HS2 has deviated drastically from international practice, desiring small diameter tunnels. This has resulted in the requirement for enormous tunnel entrance galleries unlike anything found elsewhere (as well as extremely complex ventilation systems and complicated evacuation procedures), and it is highly questionable whether any of this is cheaper than simply doing what everyone else is doing and building bigger tunnels.

The cost of tunnels is, according to studies on the topic, roughly linear with diameter - which means tunnel costs scale with the square root of cross section.
Marginally increasing cross section of the tunnel to account for a larger train cross section will have negligible effect on project costs.

I understand there is only one relatively short tunnel on the phase 2A section so any cost saving from reducing the diameter would be negligible at best. Also would changing the diameter mean that the TBM’s from phase 1 couldn’t be refurbished and reused so in terms of reducing costs it hardly seems with it.

The rest of the report in prioritising phase 2A (or the Staffordshire connector as it rebrands it) and then delivering the Cheshire connector as part of NPR makes sense although the question of what to do in the middle at Crewe (tunnel or no tunnel) is unanswered.

 

[HSTEd]

Actually it not that difficult to add a vertical concrete wall as a separation in a large tunnel, especially if after the TBM has passed need to add a concrete floor base so will be adding a reinforced concrete structure anyway, it is inverted T shape

I don't think anything tall can be slip paved, but it is possible to have wall sections on wheels that after casting a length, are moved forward ready to do next part.

Of course cut and cover and immersed tube tunnels are often built like that anyway, one trench with a structure consisting of two or more separate tunnels either side of dividing walls.

Adding a wall is not particularly difficult, but it will require significantly more work to sell it to the regulator.
Everyone more or less accepts that separate tunnel bores tens of metres apart are independent from the perspective of a fire, but an engineered structure will require more justification.

 

[LNW-GW Joint]

I understand there is only one relatively short tunnel on the phase 2A section so any cost saving from reducing the diameter would be negligible at best. Also would changing the diameter mean that the TBM’s from phase 1 couldn’t be refurbished and reused so in terms of reducing costs it hardly seems with it.

Two 700m tunnels actually, either side of Whitmore.
So shorter than anything on Phase 1.

The report also seems to show a definite route for the NPR section Liverpool-High Legh (and on to Manchester via the HS2b route).
But no specific route has been announced, while people are also saying the Ditton-Warrington route will not be used.
To my eyes, the cost and deliverability of NPR (Liverpool-High Legh-Manchester-Marsden) is completely undefined, and yet it seems to be a planning fixture.

 

[swaldman]

Also does double deck actually get you that many more seats?

Looking at the TGV we get more seats in a 9 car 800 series train.

Duplex 501 seats/200m = 2.505pax/m
Azuma 611 seats/233m = 2.62pax/m

However the French train has a dining car, if we compare a Ouigo with an all standard Azuma

Ouigo 644seats/200m = 3.22pax/m
Azuma 675seats/233= 2.89pax/m

It's an about 10% improvement in capacity, obviously we are comparing a loco hauled train to an EMU but a bit level high speed EMU isn't easy to get.

You can't fairly compare TGV seating density to British trains. On a TGV in standard class, an airline seat has enough room to fold down the tray table and work comfortably on a laptop, even for larger passengers.

 

[LLivery]

I believe twin bore tunnels in Europe are relatively common because it is the conceptually "simplest" way to meet fire safety and evacuation requirements.

Two tunnel bores with cross passages so that people can take refuge in the other bore if a fire or other incident happens.
Doing this with a single door bore requires more design work and regulatory effort than just buying another tunnel boring machine.

Ahh that makes sense, many thanks.

 

[DiscoSteve]

This is HS2A and HS2B Western Leg without either Crewe or Manchester Tunnel - I'm sure just magically chopping those two out of the spiralling HS2A/2B costs gets you the same 35% saving does it not?

 

[Mikey C]

You can't fairly compare TGV seating density to British trains. On a TGV in standard class, an airline seat has enough room to fold down the tray table and work comfortably on a laptop, even for larger passengers.

The IETs, for all their faults, have a lot of legroom in he airline seats.

 

[nwales58]

So it's basically 2A;
...
* contractors not having to worry about the total cost of ownership

So essentially how HS2 should have been done in the first place...

TCO is a raw nerve.

Optimum level of risk transfer was already being debated within consultancies where I worked in the late 1980s as Birmingham Northern Relief Road and Second Severn Crossing evolved as projects. The economists and engineers basically differed as to what was practicable (and bankers interested in financing clearly wanted to know when, if it went wrong, they could sell off the project and run away with profit or minimal loss - bit of a shock to us technical types). The Department seemed inexplicably disinterested but I don't know what was happening on the inside there.

Clearly you don't want it built on the cheap with larger maintenance bills and disruption in the first decade of operation, so some of build+maintain is essential no matter whether finance+/-operate is agood idea. Delays in opening also knacker the NPV of benefits and the profit stream for financers so contract structure matters for that too.

OTOH the government might employ and nurture a set of decent civil engineers who design it right, make sure it gets built right by the min-cost subcontractors and get the maintenance right. That idea never went down well in the consultancy world for some reason.

But nearly 40 years on with experience from dozens of projects in this country alone, HS2 so far shows we *still* do not choose, specify and write contracts to put enough risk into the private sector whilst not paying over the odds for risk better born by the public sector. It does confirm a massive risk is the customer changing their minds repeatedly.

Oh, and

It is also well known that HS2 has deviated drastically from international practice, desiring small diameter tunnels.

it was the best Oxford-trained minds who knew smaller = cheaper. I assume everyone went along with the exercise because it would be career suicide to scribble the design consequences on the back of an envelope and kill the idea.

So where do we go from here to avoid another few billion of waste?