What route may the HS2 Marsden spur take?

[MarkyT]

Assuming it's a realistic transport solution not a political gesture, I'd expect a majority in tunnel but maybe short open sections at the longest separation that avoids additional evacuation measures. That would be one or two between Ardwick and Marsden I think.

Another approach might be to vary the depth of the tunnel and come close to the surface where required for evacuation/ventilation sites, allowing shafts to be created more affordably.

 

[snowball]

Tunnelling from Ardwick also means that you can have right-hand line running from the Piccadilly HS2 junction to the tunnel portal, so avoiding the "double height viaduct" cutting through East Manchester that Andy Burnham so objects to.

If I remember correctly the stub for the eastbound NPR line is shown as deviating from the south side of the HS2 line at a point where the latter is on viaduct, so it couldn't go immediately into tunnel. The HS2 plans before parliament include an "Ardwick box structure" a bit further east, which would allow the eastbound NPR to go over both the HS2 tracks and the westbound NPR track. I doubt the plans would be changed so close to Piccadilly.

 

[MarkyT]

These seem to be feasible costs, in the great scheme of things, and they would avoid a lot of local resistance. Maybe they will choose that. Tunnelling from Ardwick also means that you can have right-hand line running from the Piccadilly HS2 junction to the tunnel portal, so avoiding the "double height viaduct" cutting through East Manchester that Andy Burnham so objects to.

Even with right-hand running, one line needs to rise up to pass over the HS2 approach tracks to achieve grade separation where the NPR Leeds line diverges from the HS2 approaches.

 

[Nottingham59]

The HS2 plans before parliament include an "Ardwick box structure" a bit further east, which would allow the eastbound NPR to go over both the HS2 tracks and the westbound NPR track.

I believe this is the latest map:


The line to Leeds crosses the main HS2 tracks after they have have started to descend towards the HS2 tunnel portal, I think.

The Ardwick box structure, where the line to Leeds crosses over the line from Leeds is very close to the junction, but does seem to require that double height to be continued for longer.

My point is that if the tunnel to Marsden is to run from Ardwick, as Bald Rick says, then this cross-over box structure would not be needed, as the Leeds lines could cross over once they were in (separate) tunnels.

The height profiles are shown on the map here: https://assets.publishing.service.g.../2DE01-MWJ-CV-DPP-M003-320059_watermarked.pdf



EDIT: And interestingly, the first map above also shows the NPR line to Leeds extending well beyond Ardwick to form a four-track formation heading past Ashburys towards Guide Bridge...

Map taken from here: https://www.gov.uk/government/publications/volume-2-map-book-ma07-davenport-green-to-ardwick

EDIT 2: And, for completeness, here is a 3D visualisation of the Ardwick Box:

Image taken from: https://assets.publishing.service.g.../uploads/attachment_data/file/1046631/M22.pdf (Warning: 300-page pdf)

 

[snowball]

That map in your first edit in #34 is extremely remarkable. I hadn't seen it before. It's number 93 of 93 pages in the map book, and it actually seems to show the proposed NPR route eastward from the Ardwick box structure. I had no idea anything like it was in the public domain. As you say it's heading straight for the Guide Bridge line. It seems to destroy any idea that the route would go into tunnel early on.

 

[Nottingham59]

I had no idea anything like it was in the public domain.

Nor had I!

The mapbook was published in Jan 2022 as part of the Environmental Statement for the HS2 bill. I suspect it's gone through a different pre-publication approval committee from other material I've seen, which has consistently avoided saying anything about possible routes.

 

[Narrowgauge725]

Let think this through it is north of Watford Gap, expensive tunnel, no. Lots of little expensive tunnels, no. Upgrade existing PW to 4 track, slight possibility. Spend the money on new railways in London, yes yes yes. Just view from a Yorkshireman.

 

[quantinghome]

Here's a question - when was the last railway tunnel in the north of England built? Rebores, realignments and build-overs don't count!

 

[Greybeard33]

That map in your first edit in #34 is extremely remarkable. I hadn't seen it before. It's number 93 of 93 pages in the map book, and it actually seems to show the proposed NPR route eastward from the Ardwick box structure. I had no idea anything like it was in the public domain. As you say it's heading straight for the Guide Bridge line. It seems to destroy any idea that the route would go into tunnel early on.

That map will have been drawn before the Government decision as to which NPR route option to select in the IRP. Therefore the NPR line on the map will represent nothing more than a working assumption about the NPR route, which HS2 Ltd adopted for the purpose of designing the passive provision for the Ardwick junction.

It might well represent an option for a minimum cost upgrade of the existing route to Stalybridge, rather than the selected option of a new line from Piccadilly to Marsden.

 

[Sonik]

That map will have been drawn before the Government decision as to which NPR route option to select in the IRP. Therefore the NPR line on the map will represent nothing more than a working assumption about the NPR route, which HS2 Ltd adopted for the purpose of designing the passive provision for the Ardwick junction.

It might well represent an option for a minimum cost upgrade of the existing route to Stalybridge, rather than the selected option of a new line from Piccadilly to Marsden.

Given that these plans are already well on the way to parliamentary approval, the outcome would seem to be a foregone conclusion, because further changes could delay HS2 to Manchester.

What constitutes a 'new' line is a mater of semantics.

 

[snowball]

Given that these plans are already well on the way to parliamentary approval, the outcome would seem to be a foregone conclusion, because further changes could delay HS2 to Manchester.

What constitutes a 'new' line is a mater of semantics.

The line east of the Ardwick box structure is not part of the works in the bill. The discovery of map 93 does not have any effect on what is or isn't in the bill. The box structure is part of the bill and represents a constraint on possible routes for NPR, but no bigger a constraint than it was before map 93 was discovered.

 

[billh]

Regarding housing built close to the old Micklehurst route, the LNWR had to change their plans in the Dukinfield area in the 1880s because of objections by the local authority. A number of houses were to be demolished to make way for the mostly viaducts route. This would reduce the amount of rates collected by the LA. Some compromise was reached where not so many houses were lost.
In Uppermill, it appears that the old route is taken up by gardens not the houses, but 100mph trains whistling past the lounge window might not please some residents. The sports centre is built on the site of the Goods Yard and the main line is now an access road which could be re-routed.

 

[matacaster]

Here's a question - when was the last railway tunnel in the north of England built? Rebores, realignments and build-overs don't count!

My guess would be woodhead.

 

[snowball]

Here's a question - when was the last railway tunnel in the north of England built? Rebores, realignments and build-overs don't count!

There's the 1950s bore at Woodhead - not clear whether that counts as a rebore or realignment in your terms. Or there's Harecastle in the 1960s, which you might count as a rebore or realignment or not far enough north.

 

[wellhouse]

Here's a question - when was the last railway tunnel in the north of England built? Rebores, realignments and build-overs don't count!

Merseyrail 1970s and Tyne & Wear Metro 1980s?

 

[fishwomp]

Let think this through it is north of Watford Gap, expensive tunnel, no. Lots of little expensive tunnels, no. Upgrade existing PW to 4 track, slight possibility. Spend the money on new railways in London, yes yes yes. Just view from a Yorkshireman.

The problem is that the spend on expensive tunnels in the South is wrong, not that re-quadding an existing 4-track alignment in the North is wrong.

There are cheaper ways to obscure the view of Manchester than using tunnels, and east of Staly, it's a decent view (except for in the Standedge).

 

[61653 HTAFC]

There's the 1950s bore at Woodhead - not clear whether that counts as a rebore or realignment in your terms. Or there's Harecastle in the 1960s, which you might count as a rebore or realignment or not far enough north.

I wasn't sure it counted either... having considered it a bit I'd say it does- it isn't a rebore (as per that one near Bolton a few years ago) it's an entirely new bore adjacent to the old ones. Being right next to the old ones I'd argue it isn't really a realignment either.

 

[superkev]

If the new line is actually built would there still be a need for the old line particularly Standege tunnels.
K

 

[Gareth]

I assume the stoppers would still want to run through from Manchester to Huddersfield. Freight too, presumably.

 

[Nottingham59]

If the new line is actually built would there still be a need for the old line particularly Standege tunnels.
K

Oh, definitely. The whole point of building a new line is so that you can separate stopping trains from the fast services which will only stop at Huddersfield. Otherwise they get in the way of each other and severely limit the number of trains per hour that the line can carry.

 

[Gareth]

I think what he had in mind was the stoppers becoming two separate services terminating at Greenfield and Marsden respectively.

 

[quantinghome]

There's the 1950s bore at Woodhead - not clear whether that counts as a rebore or realignment in your terms. Or there's Harecastle in the 1960s, which you might count as a rebore or realignment or not far enough north.

In both cases they were effectively replacing existing infrastructure, allowing the lines to be electrified.

Merseyrail 1970s and Tyne & Wear Metro 1980s?

That's probably it. The last new build tunnels for a new service.

 

[61653 HTAFC]

I think what he had in mind was the stoppers becoming two separate services terminating at Greenfield and Marsden respectively.

There was discussion on another thread about how commuting patterns from Slaithwaite and Marsden have changed since through services to Manchester became the rule rather than the exception 30+ years ago. Cutting the bit through the tunnel now would be a huge mistake, and I'm not sure what problem it would solve. I know the tunnel is long, but is it particularly difficult to maintain for any other reason?

 

[Nottingham59]

OK, time for the crayons.... Mods, please move if this is too speculative for this thread. Red is TBM-bored tunnel, blue is surface line, green is cut-and-cover tunnel, and yellow represents portals and access/ventilation shafts.

I couldn't find a sensible route that used the Micklehurst Loop line, but so this is now my preferred route for a new NPR line from Ardwick to Marsden. The design criteria were:

• Design speed = 230km throughout (matching the design speed of the HS2 spur to Manchester)
• Minimum radius of curves = 2000m
• Maximum gradient = 2%
• Access / evacuation points within 2km of every point in the tunnels
• Tunnel diameter = whatever is needed for the design speed

I don't know much about civil engineering, or geology, or coal mining, so I can't say if this route would be practical or not, but it was instructive trying to work it out.



From West to East:

ARDWICK
Some expert commentators on here have said that the tunnel will start at Ardwick, but I can't see how there's enough space to drop a line from the top of the Ardwick Box structure to an underground tunnel portal, so I would merge onto the existing four track alignment past Ashburys, Gorton and Fairfield stations. Google streetview suggests there should be enough space. The old 1500V DC overhead portals are still in place, though I don't expect to re-use these! Speed along this section as fast as can be accommodated within the existing footprint, hopefully 230km/h (142mph).

WESTERN PORTAL
Continuing past Guide Bridge station means either a very deep descent to get under the River Tame on a straight line, or a sharp curve to the North (currently 25/30mph, and not easy to straighten much). This wouldnt matter if every NPR train stopped at Guide Bridge, which has easy access to the M60, but I'm assuming that will not be an NPR requirement.

So I propose the Western Portal should be between Fairfield and Guide Bridge, using low grade industrial land between the railway and the canal.


This would require a new bridge under the M60 to avoid excessive curvature, even though the existing M60 bridge was built with space for four lines.

NEW ASHTON TUNNEL
5000m in length, passing under Ashton town centre and curving towards the North. I don't know how deep a tunnel under buildings needs to be, and whether coal mining would be a problem here. Needs an access/evacuation shaft in Ashton town centre, and one on the northern outskirts. The tunnel then rises steeply to emerge on higher ground beyond the developed area. The average gradient is 1.2%, but may be steeper in places.

GREEN TUNNEL
2000m across open country, roughly alongside the valley of the River Medlock, rising at 1% gradient. A green tunnel is a cut-and-cover railway built in a cutting, and covered over to minimise noise and nuisance. It costs around half of that of a bored tunnel. I've assumed the cutting is 10m deep.

SPRINGHEAD TUNNEL
3000m bored tunnel, emerging onto a viaduct over the River Tame, between Uppermill and Delph.

TAME VIADUCT
Approximately 300m in length, at 10m elevation above the river, and 5m above the long-distance footpath. Located away from local properties, with the rail tracks enclosed in tubes to minimise noise and disturbance. Gives access/evacuation routes to tunnels north and south.



NEW STANDEDGE TUNNEL
8500m from the Tame Viaduct to beyond Marsden.

The line proceeds in bored tunnel at almost level gradient, passing to the West of Diggle within the hillside, but allowing a level access and evacuation route to the valley floor at Diggle, and then rising to the altitude of the existing rail and canal tunnels (210m above sea level) - again to allow level access/evacuation here. See the main map above for details.

EASTERN PORTAL
After this mid-way access point, the tunnel descends to pass under the River Colne, with an access/ventilation shaft in the valley near to the Standedge Tunnel visitor centre, and then curves to the East to rejoin the existing alignment between Marsden and Slaithwaite stations. This avoids the curve around Marsden station.


Beyond the portal, the existing line is straight enough to allow high speed running until the kink at Slaithwaite Viaduct (500m radius, currently 75/85 mph). This could be straightened out, but that is outside the scope of this exercise.

Any thoughts, comments, obeservations, alternative proposals gratefully received.

 

[fishwomp]

EASTERN PORTAL
After this mid-way access point, the tunnel descends to pass under the River Colne, with an access/ventilation shaft in the valley near to the Standedge Tunnel visitor centre, and then curves to the East to rejoin the existing alignment between Marsden and Slaithwaite stations. This avoids the curve around Marsden station.

View attachment 116814
Beyond the portal, the existing line is straight enough to allow high speed running until the kink at Slaithwaite Viaduct (500m radius, currently 75/85 mph). This could be straightened out, but that is outside the scope of this exercise.

Any thoughts, comments, obeservations, alternative proposals gratefully received.

This [Marsden tunnel separate from another Standedge bore] - I have been wondering for a while if what was needed was not another 3 miles of tunnel (aren't 3 holes enough through there?) - but instead a half mile tunnel that let the curve be reduced and line speed improved. Thanks for drawing it - the difference is that I'd connect to the existing tunnels, not a new one.

 

[Snow1964]

Going to include todays (27th June) Transport & Works Order for Huddersfield-Dewsbury as it is effectively a continuation of the routing for reference

Basically refers to 4 tracking, 2 pairs of tracks (fast and slow), Junction segregation, electrification. So really need to be able to connect into the improved North Trans Pennine works

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1085988/huddersfield-to-westtown-dewsbury-improvements-order-application-decision-letter.pdf

 

[tomuk]

This [Marsden tunnel separate from another Standedge bore] - I have been wondering for a while if what was needed was not another 3 miles of tunnel (aren't 3 holes enough through there?) - but instead a half mile tunnel that let the curve be reduced and line speed improved. Thanks for drawing it - the difference is that I'd connect to the existing tunnels, not a new one.

Why would you want to get involved in the complex and historic Standege Tunnels. I believe that one of the old bores is used as access to adjacent connected canal tunnel plus you have the overhead sluice to the canal feeder. Best left well alone.

 

[fishwomp]

Why would you want to get involved in the complex and historic Standege Tunnels. I believe that one of the old bores is used as access to adjacent connected canal tunnel plus you have the overhead sluice to the canal feeder. Best left well alone.

Cost. No way is a new 3 mile tunnel cheap - and someone has to pay for this. If they're historic, using them keeps them in good shape; they're not that complex - not compared to building a new tunnel; even moving the canal feeder is easier if necessary (it was redecked fairly recently, so they would know how to do this).

 

[Nottingham59]

I'd connect to the existing tunnels, not a new one.

That's a great idea, but I really don't know how much it would save. For the higher speeds, you'd have to drill it out to a wider diameter, which will cost for the boring machine and all the new concrete lining segments, so it might not save that much compared to a new bore.

And it appears that the fast lines are going to be on the southern side of the alignment, so I'm going to have to modify the East portal as shown here, which puts it a 15-20m lower elevation than before.

At least it gives a nice clear field to set up the TBMs, I guess.

 

[zwk500]

Cost. No way is a new 3 mile tunnel cheap - and someone has to pay for this. If they're historic, using them keeps them in good shape; they're not that complex - not compared to building a new tunnel; even moving the canal feeder is easier if necessary (it was redecked fairly recently, so they would know how to do this).

Given the state the tunnels are reputed to be in, I wouldn't be surprised if boring a new, fresh hole is cheaper than trying to fix them up. Even the wide bore is unlikely to meet the requirements for the air displacement envelope at c.225km/h, and getting a waiver on a safe evacuation route (diving into the canal doesn't count) would also be tricky.