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An underground station at Manchester Piccadilly “would introduce significant construction complexity”, cost around £5bn more and take up 13 years longer to build, a comparative study by HS2 Ltd concludes.
HS2 Ltd carried out the assessment following pressure from northern politicians and engineers who support the underground option as a way to maximise the potential connectivity and value of the HS2 station, combining it with a Northern Powerhouse Rail station to boost connectivity across the North.
However, in April transport secretary Grant Shapps categorically ruled out the idea, adding that the government and HS2 Ltd was agreed on the surface level terminus.
HS2 Ltd has now released a 261-page assessment that compares three underground options with the proposed surface station.
The baseline design for the station comprises elevated track on viaduct and fans out to six terminating lines. The new surface station is on the same level and adjoins the existing Network Rail station.
HS2 compared the baseline design with three underground options. The first – and HS2 Ltd’s preferred underground option – assumes shallow cut and cover station box and integrated throat. In the other two underground scenarios the throat is mined.
For the underground options, the station is a through station which comprises symmetrical throat layouts both south and north of the station box.
HS2 Ltd concludes that “all options would introduce significant construction complexity” as well as requiring “significantly greater volumes of material to be imported and exported” thus doubling the estimated number of HGV movements to and from site.
The report – Manchester Piccadilly High Speed Station: Design of an Alternative Underground Station – adds that the two scenarios which use mined caverns “introduce significant risk both in terms of safety and of damage to existing structures due to settlement risks”.
It adds: “The mined approaches have no precedent for such large caverns in close proximity to each other in these ground conditions” adding that “their feasibility will depend on detailed site investigation, design analyses and possibly full-scale trials demonstrating the rock has sufficient strength and that groundwater ingress can be controlled by grouting or other measures”.
Meanwhile, it’s preferred underground option ranked “lowest on environmental impact but it ranks highest on strategic fit, urban design, construction, health and safety, commercial development and cost”.
In terms of delivery times, the report adds that “the three underground station options have estimated delivery-into-service date ranges that are 7-13 years later than the delivery-into-service date of 2036 for the current hybrid Bill scheme”
On cost, the report concludes: “each of the three underground options […] is estimated at £12.3Billion, £11.4Billion, and £12.1Billion respectively. These compare to a comparative cost of £7Billion for the baseline. This includes civils, railway systems and land and property costs [...] along with indirect costs and contingency.”
A breakdown of costs reveals that civils work at the station itself would be the main additional cost, with each of the three underground options allocated around £2bn extra for this work.
Additional contingencies of around £2bn are also attributed to the underground options “to reflect the conceptual nature of the designs and the lack of survey and design details”. (Full breakdown of costs below.)
The report concludes: “It is HS2 Ltd’s view that further detailed development of the options, based on the agreed scope and requirements of this study, is unlikely to significantly change the overall assessment and comparative difference between a surface and underground high-speed station at Manchester Piccadilly, particularly in respect to cost and programme.
“It is therefore HS2 Ltd’s recommendation that the Proposed Scheme for a Surface Station, to integrate HS2 and NPR at Manchester High Speed Station, is retained for the Phase 2b Western Leg hybrid Bill design, on grounds of cost, construction safety and programme implications to the Delivery-into-service date of HS2 to Manchester.”
*Image credit WestonWilliamson+Partners
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Assessments like this lose credibility when it is stated the station completion may be up to 13 years later than the baseline. That means the ‘planners’ have concluded it could take longer to build than the whole of Crossrail. It would be interesting to see the planning work in some detail that leads to this conclusion!
A few comments on this:
They suggest that a new station would cost around £3billion. Option B1 would be very similiar in size and configuration to HS2’s Old Olk Common Station in London which is reported to cost less than £1billion. How can the Manchester Piccadilly Underground Statio cost 3 times as much??
Reported delays 7-13 years seems rather exaggerated. The report also ignores an option to run HS2 train services initially into the existing Paccidilly surface station with a platform extended to accomodate 400m log trains. This option using existing NR infrastructure would allow HS2 services to start running into Manchester sooner than in HS2’s baseline case.
The report doesn’t mention that the MetroLinkline could by diverted around station works to allow it to remain open.
The report avoids looking at net economic benefits of allowing direct HS2 train services to run from Leeds to London and Birmingham via Manchester. This would be a significant benefit.
A lot of effort seems to been expended but it has missed exploring potentially better and more economic options.
It seems as if the report was designed to conclude “let’s just carry on as we are”.
Manchester looks destined to build a terminus HS2/NPR station that it will come to regret.
The underground station layout is – rightly – more extensive than Old Oak. It features additional parallel moves to separate through and terminating/starting trains, whereas at Old Oak this functionality is limited and essentially ’emergencies only’. The EoA-SvL distances (overlaps in old money) are not shown but will be critical; again at Old Oak they are too short for routine use in some cases. So the whole box will, and should be, bigger. They do seem to have got the shafts right, closing up towards the station so as to make the intershaft spacing equal in time rather than distance. Whether that makes the cost difference I cannot say, but we could quite happily have made Old Oak twice the size had that been possible!
The idea is to run NPR trains that run from Liverpool and Warrington to Leeds and beyond, to run into Piccadilly terminal station then REVERSE out. Crazy! A new line to link the north like this?
Having terminal stations in inland cities is just plain stupid.
£3.5bn surface vs £5.5bn underground before contingency looks very competitive to me. Also notably the NPR route is cheaper with an underground station than a surface station according to their figures.
We need to build a faster rail system across London. Building it underground looks a bit complicated and might cost more than the two shillings and sixpence we budgeted for, so lets put it all on a long viaduct!
Has HS2 learned nothing from Crossrail?
Why doesn’t this government want to invest in major future infrastructure projects, especially ones north of Watford? And don’t ask Channel 4 about moving their HQ to Leeds only to find out that there won’t be a high speed connection to London.
As to ” “significantly greater volumes of material to be imported and exported thus doubling the estimated number of HGV movements to and from site”. You’re building it next to an existing rail connection – why use HGVs, for heavens sake?
Liverpool has an established film industry with major films like Batman, etc filmed there. Channel 4 rejected Liverpool on transport grounds. The city is ringed by motorways and has its own underground metro. The real reason was because HS2 would not have direct train to the city. So they end up in Leeds with a worse line to London than Liverpool.
This does all sound like finding the evidence to justify a decision already made. Why would it take 7-13 years longer? How is the cost-benefit assessed in totality – i.e. with NPR.
One must no lose sight of the big picture.
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▪️ HS2 north of Crewe will only serve provincial city Manchester. Manchester is no Munich or Barcelona.
▪️ Phase 2b will cost £32bn, with most of that for the link to just Manchester.
▪️ Network Rail are to upgrade the WCML from Crewe to Preston. Existing 2-track section cab be 4-track. Sections can be 160mph.
▪️ Manchester already has the “direct” WCML spur line to HS2 at Crewe.
▪️ Piccadilly Station is a terminal station facing the wrong way.
▪️ Ordsall Cord links Piccadilly and Victoria.
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▪️ In addition to the WCML upgrade, the WCML spurs to Liverpool and Manchester can be upgraded to improve speed.
▪️ East-west NPR is best run via east-west Victoria (made into a Berlin type of superstation), not Piccadilly facing the wrong way.
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A quick analysis tells you that HS2 north of Crewe is not needed as the WCML upgrades can do the job. Piccadilly needs demolishing, except for the two through platforms, with a new “through” superstation built for HS2/NPR at Victoria. Terminal stations in inland cities are very inefficient.
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Few can see HS2 Crewe to Manchester built as the it offers little value.