The best way to electrify the Chiltern Network and the Snow Hill Lines

RailWonderer · 14 May 2024

Partial electrification and bi-modes are the most realistic solution and for Chiltern to continue operating to Aylesbury services. They are S-bahn style routes where it would be absurd to send the Met line to given the Tube's main purpose is to serve London and its immediate areas, not plod along halfway into Buckinghamshire.

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Bletchleyite · 14 May 2024

RailWonderer said:
Partial electrification and bi-modes are the most realistic solution and for Chiltern to continue operating to Aylesbury services. They are S-bahn style routes where it would be absurd to send the Met line to given the Tube's main purpose is to serve London and its immediate areas, not plod along halfway into Buckinghamshire.

I don't think you understand what the Metropolitan Line actually is. It's only part of the Tube because of history, it's really more like a single ended Thameslink, the Merseyrail Northern Line or an older version of the Lizzie. It has "big railway" features like fasts and semifasts, and a long 4-track section. It has very little in common with the rest of the Tube.

"Plodding along halfway into Buckinghamshire" is exactly what it does and is exactly what it was built for - to create the concept of London commuting when it wasn't really a thing!

Give John Betjeman's "Metroland" a watch, it's superb and gives you the background.

(I still think it's a real shame Aylesbury didn't go onto Crossrail as was the BR-era plan - it would have solved this and provided a significant regenerative input on what is at times a rather downtrodden town that very much plays second fiddle to Milton Keynes - and if it carried on a bit further into the nothingness an eco new town or two could have sprung up in the way the Metropolitan Railway had intended years before - I'll be honest, I do love the "country branch line" feel of the Aylesbury branch and the quirk of it almost becoming a Tube line at Amersham, perhaps a bit of a northern version of the Uckfield line, but it would have done so much more for the area to give it more than a short DMU or two an hour)

RailWonderer · 14 May 2024

Bletchleyite said:
I don't think you understand what the Metropolitan Line actually is. It's only part of the Tube because of history, it's really more like a single ended Thameslink, the Merseyrail Northern Line or an older version of the Lizzie. It has "big railway" features like fasts and semifasts, and a long 4-track section. It has very little in common with the rest of the Tube.

"Plodding along halfway into Buckinghamshire" is exactly what it does and is exactly what it was built for - to create the concept of London commuting when it wasn't really a thing!

Give John Betjeman's "Metroland" a watch, it's superb and gives you the background.

That doesn't change the fact as mentioned above, dual voltage or bi-mode is the best solution for the route. For the sake of consistency, the Tube's reach out of London should be limited and anything further afield should be for mainline trains only, or Purple tube branding and run by TfL.

Bletchleyite · 14 May 2024

RailWonderer said:
That doesn't change the fact as mentioned above, dual voltage or bi-mode is the best solution for the route. For the sake of consistency, the Tube's reach out of London should be limited and anything further afield should be for mainline trains only, or Purple tube branding and run by TfL.

Again, the Metropolitan Line is a quirk of history and isn't the same as the rest of the Tube. It also isn't similar enough to the Lizzie to give it that branding, and would be confusing. I think there's a need to accept it for what it is - kind of a thing in its own right.

Sometimes you need exceptions to rigid categorisation - see stuff like Deutsche Bahn running ICs as REs on peripheral branches after they've done the main IC run.

(I'm similarly unsure that running the Met to Aylesbury Vale is the right option - but I'm just emphasizing that it's no less "proper railway" than the Overground or some of the South London third rail locals).

12LDA28C · 14 May 2024

Bletchleyite said:
AVP is likely to become much busier as a load of housing estates continue to go up around it (it was formerly in the middle of a field). I suspect in time given that Aylesbury isn't really a regional destination it will be busier than that.

Slowing its service to nearly 90 minutes to Marylebone or serving it only with East West Rail (if it ever happens) wouldn't be a good plan, so if going the Met way you'd need to take the Met all the way out there.

Aylesbury Vale Parkway isn't a destination anyway though of course. Aylesbury is a busy point of origin and AVP is unlikely to ever equal it in terms of passenger numbers.

HSTEd said:
The depot doesn't appear to have much storage space for trains, is it a primary maintenance facility?

If it is a relatively minor facility the question should be asked of how critical that facility is in a world where Chiltern doesn't have to provide trains for Aylesbury-London via Harrow any more.
Ofcourse, for a large part of the current Chiltern fleet, the only option is already via Princes Risborough - if they don't have trainstops fitted.

Aylesbury is Chiltern's primary maintenance facility and the only location that can carry out tyre-turning, engine changes and suchlike. Trains aren't fitted with trainstops.

Trainbike46 said:
It is a maintenance facility - though how important it is for Chiltern as a whole I do not know. Apparently it maintains 165s and 168s

Aylesbury is the main maintenance Depot on Chiltern. The 68s and Mk3s are also tyre-turned there although maintained at Wembley and to a lesser extent at Stourbridge.

ChiefPlanner · 14 May 2024

Some knowledge as to the Aylesbury route , having been involved in Crossrail 1 (the one that got cancelled in 1994)-

Tricky to get OLE up Amersham to Rickmansworth due to the tight clearances on the 4 tracked section , though not impossible. North of Ricky not too tricky , and that included the Chesham line. The plan then was for 4 semi-fast to Aylesbury with 6 turning round at Amersham , 2 possibly going to Chesham. Truth is , without some changes to Green belt etc 4 class 341's an hour was really too much service to AY.

I would think the wiring of Marylebone to Harrow would be tricky - not just the tunnel section , but again tight clearances on the Met section from Neasden South northwards ........

Bletchleyite · 14 May 2024

12LDA28C said:
Aylesbury Vale Parkway isn't a destination anyway though of course. Aylesbury is a busy point of origin and AVP is unlikely to ever equal it in terms of passenger numbers.

I think in 20 years' time AVP could well be busier than Aylesbury itself. It's much easier to reach by car from the substantial hinterland than the often congested town centre, for one, and while the area is to expand it's likely to remain residential. That it only gets roughly half the service presently suppresses demand. Much of the work in Aylesbury is low paid, so inbound commuting by rail, while it exists, is fairly limited, and the area is very car-dependent generally.

12LDA28C · 14 May 2024

cslusarc said:
I would start electrification from Marylebone because Chiltern's 165 are older than any Turbostar at WMR.

Which is probably the most difficult part of the whole route to electrify, certainly with OHLE at least. Anyway, the tender is already out for the Class 165 replacement and you're not going to get any electrification completed before those new units arrive.

Bletchleyite said:
I think in 20 years' time AVP could well be busier than Aylesbury itself. It's much easier to reach by car from the substantial hinterland than the often congested town centre, for one, and while the area is to expand it's likely to remain residential. That it only gets roughly half the service presently suppresses demand. Much of the work in Aylesbury is low paid, so inbound commuting by rail, while it exists, is fairly limited, and the area is very car-dependent generally.

Most of the housing near AVP has now been completed. Who's talking about inbound commuting? The vast majority of people using Aylesbury are travelling to London, the majority commuting but plenty for leisure too.

mr_jrt · 14 May 2024

Ideally you would cut the Met back to a rebuilt Ricky and confine it to the slow lines (or perhaps, give Ricky to Chiltern completely). The Met then just provides metro service to Watford, Uxbridge, and maybe Ricky. Chiltern then gets OHLE on the fast lines and operates Marylebone to Chesham & MKC via Amersham. The line can then be upgraded if needed for faster speeds and longer platforms. The only real major obstacle is terminal capacity at Marylebone, and that'll need a grand solution all of its own regardless just to cater for Chiltern's growth, be it OOC platforms, a new crossrail-esque tunnel somewhere (LTS?), or some Godzilla-style "redevelopment" of the BNP Paribas building.

ChiefPlanner · 14 May 2024

mr_jrt said:
Ideally you would cut the Met back to a rebuilt Ricky and confine it to the slow lines (or perhaps, give Ricky to Chiltern completely). The Met then just provides metro service to Watford, Uxbridge, and maybe Ricky. Chiltern then gets OHLE on the fast lines and operates Marylebone to Chesham & MKC via Amersham. The line can then be upgraded if needed for faster speeds and longer platforms. The only real major obstacle is terminal capacity at Marylebone, and that'll need a grand solution all of its own regardless just to cater for Chiltern's growth, be it OOC platforms, a new crossrail-esque tunnel somewhere (LTS?), or some Godzilla-style "redevelopment" of the BNP Paribas building.

Rebuilding Ricky was an option at one time - but there was (and is) a need to maintain the berthing sidings there .......

Transferring a few Chilterns to either West Ealing , or better still OOC would allow excellent connectivity into the Elizabeth line (and release a few slots into Marylebone)

None of this could happen quickly though.

HSTEd · 14 May 2024

Attempting to relectrify the line between Harrow and Amersham would probably be expensive enough to render the whole project implausible.
Given the cost escalation of 25kV installations I am not hopeful a good business case could be made for such work.

Dual voltage units would have to be procured, or the line transferred to the Metropolitan line. The former would be a non zero operational headache for Chiltern which is not present in the latter case.

I must admit I am not a fan of attempting to rigidly define service groups by role, or by attempting to impose artificial geographical limits on the extent of services like London Underground.

Cutting through the Gordian knot by serving the Aylesbury line via the Met and then maintaining a service via Princes Risborough seems the simplest solution. At least to by mind!
EDIT:

If electrification of the Chiltern Main Line proceeds, the acceleration from electrification might make a semi fast via Princes Risborough practical in a time competitive with the current direct offering. So I'm not sure anyone loses anything!

mr_jrt · 14 May 2024

ChiefPlanner said:
Rebuilding Ricky was an option at one time - but there was (and is) a need to maintain the berthing sidings there .......

Transferring a few Chilterns to either West Ealing , or better still OOC would allow excellent connectivity into the Elizabeth line (and release a few slots into Marylebone)

None of this could happen quickly though.

These things tend to snowball, but I believe a lesser considered part of the Croxley link was to gain access to the disused sidings south of Watford Junction for Met stabling, and I believe that the current (aka former) Watford station was also to be used for stabling. Perhaps an option for justifying bringing that project back to life?

Regardless, I believe the rebuilt Ricky proposals from the 60's were to build a new straighter station alongside the stabling, I don't think the intention was to obliterate all of it?

EDIT: Just remembered there was the former Croxley depot site that now houses some small light industrial retail. Another option, perhaps?

HSTEd said:
Attempting to relectrify the line between Harrow and Amersham would probably be expensive enough to render the whole project implausible.
Given the cost escalation of 25kV installations I am not hopeful a good business case could be made for such work.

I doubt it. Once you isolate the routes it's just plain vanilla double track OHLE, abet adjacent to a double track 4th rail installation, no different to what is the case along the London section of the WCML (and what will be the case from Finchley Road to at least Neasden Junction once Chiltern gets its wires). Given the modern propensity against portals, you could probably even keep all the uprights on the down side, well away from the 4th rail lines.

Bletchleyite · 14 May 2024

HSTEd said:
If electrification of the Chiltern Main Line proceeds, the acceleration from electrification might make a semi fast via Princes Risborough practical in a time competitive with the current direct offering. So I'm not sure anyone loses anything!

Quite a lot do change between the Aylesbury branch and LU at Harrow on the Hill, to be fair.

RailWonderer · 14 May 2024

HSTEd said:
Dual voltage units would have to be procured, or the line transferred to the Metropolitan line. The former would be a non zero operational headache for Chiltern which is not present in the latter case.

? The 350/1 are dual voltage as are the 387s which both used it daily hassle free and currently the 700s use it day in day out with no issues at all.

Bletchleyite · 14 May 2024

12LDA28C said:
Most of the housing near AVP has now been completed.

For now. There WILL be more. The UK needs massively more housing, particularly in the South East.

TBH I reckon if you extended all trains back to AVP rather than just half of them it would at least match Aylesbury's popularity. It's artificially suppressed by giving it a lesser service - as so many users arrive by car they just go for the one with more trains. (Personally I like the civility of a terminus so I often use it myself, plus free Sunday parking).

ChiefPlanner · 14 May 2024

mr_jrt said:
These things tend to snowball, but I believe a lesser considered part of the Croxley link was to gain access to the disused sidings south of Watford Junction for Met stabling, and I believe that the current (aka former) Watford station was also to be used for stabling. Perhaps an option for justifying bringing that project back to life?

Regardless, I believe the rebuilt Ricky proposals from the 60's were to build a new straighter station alongside the stabling, I don't think the intention was to obliterate all of it?

EDIT: Just remembered there was the former Croxley depot site that now houses some small light industrial retail. Another option, perhaps?

I doubt it. Once you isolate the routes it's just plain vanilla double track OHLE, abet adjacent to a double track 4th rail installation, no different to what is the case along the London section of the WCML (and what will be the case from Finchley Road to at least Neasden Junction once Chiltern gets its wires). Given the modern propensity against portals, you could probably even keep all the uprights on the down side, well away from the 4th rail lines.

There was an option worked for wiring the ex Met lines in the manner described , plus a feed off the grid at Mopp End ! (forget the old Croxley depot site - long gone and built over)

It was noticeable that once Tring got a regular 4 tph service - loadings from there increased solidly , some of which was railheading from the Aylesbury corridor attracted by the better journey times , parking etc......

Bletchleyite · 14 May 2024

ChiefPlanner said:
It was noticeable that once Tring got a regular 4 tph service - loadings from there increased solidly , some of which was railheading from the Aylesbury corridor attracted by the better journey times , parking etc......

Yep, there's certainly a lot of that goes on (and Tring is a terminus too so you keep the civility of one, though I think unlike myself most commuters prefer to board the faster train and whine than the slower one starting there - though of course with Tring the faster one starts there now).

12LDA28C · 14 May 2024

HSTEd said:
Dual voltage units would have to be procured, or the line transferred to the Metropolitan line. The former would be a non zero operational headache for Chiltern which is not present in the latter case.

If the Metropolitan line were extended to Aylesbury or AVP that certainly would be an operational headache for Chiltern at Aylesbury as various walking routes cross the line and at least one platform would be shared between the Met operation and Chiltern. Anyway this is all pie-in-the-sky as there is pretty much zero chance of the 3rd/4th rail being extended north of Amersham.

Krokodil · 14 May 2024

Bletchleyite said:
It's such a shame Aylesbury wasn't brought into Crossrail as was in the original BR plan

That's interesting, I didn't know that

ChiefPlanner said:
Transferring a few Chilterns to either West Ealing , or better still OOC would allow excellent connectivity into the Elizabeth line (and release a few slots into Marylebone)

Flipping that idea on its head, could you instead extend the Lizzie line's OOC terminators down the Chilterns (say to Aylesbury via PR) as a replacement for the stopping services? Then there's not even the need to change, you'd board at Gerrards Cross and be whisked straight into the heart of the capital.

mr_jrt · 14 May 2024

Krokodil said:
Flipping that idea on its head, could you instead extend the Lizzie line's OOC terminators down the Chilterns (say to Aylesbury via PR) as a replacement for the stopping services? Then there's not even the need to change, you'd board at Gerrards Cross and be whisked straight into the heart of the capital.

That was my original preference, back before the up relief flyover was removed from the OOC plans when the WCML link was given up on.

ChiefPlanner · 14 May 2024

Krokodil said:
That's interesting, I didn't know that

Flipping that idea on its head, could you instead extend the Lizzie line's OOC terminators down the Chilterns (say to Aylesbury via PR) as a replacement for the stopping services? Then there's not even the need to change, you'd board at Gerrards Cross and be whisked straight into the heart of the capital.

Possibly a bit too far - but turning some services a bit closer in - like Gerrards Cross or West Ruislip could be valuable. Trouble is one would have to gauge the service levels very carefully.

Crossrail to Aylesbury was worked up in considerable detail , operationally I did a lot of it , and the sponsoring MP for the Parliamentary Bill was no less than the newly minted MP for the constituency. That did not save the Bill .......(basically the country could not afford the Jubilee Line extension , Thameslink and Crossrail) - on reflection , the Aylesbury section was very expensive to do as apart from getting to Neasden South via a tricky Old Oak - Dudden Hill route , the infrastructure needed a considerable spend on it for the maximum of 10 tph that was politically acceptable for London Underground at the time. )

HSTEd · 14 May 2024

mr_jrt said:
I doubt it. Once you isolate the routes it's just plain vanilla double track OHLE, abet adjacent to a double track 4th rail installation, no different to what is the case along the London section of the WCML (and what will be the case from Finchley Road to at least Neasden Junction once Chiltern gets its wires). Given the modern propensity against portals, you could probably even keep all the uprights on the down side, well away from the 4th rail lines.

Based on current experience, vanilla double track OHLE will cost something like £9m per route kilometre. It will get very expensive very quickly.

I doubt truncating the Metropolitan Line to Rickmansworth and dumping people into Marylebone (a markedly inferior terminus to Baker Street is almost all ways, let alone through trains to Aldgate) will be particularly popular with the user base either.
Chorleywood, for example, has far more traffic on LU than it does on the Chiltern.

12LDA28C said:
If the Metropolitan line were extended to Aylesbury or AVP that certainly would be an operational headache for Chiltern at Aylesbury as various walking routes cross the line and at least one platform would be shared between the Met operation and Chiltern. Anyway this is all pie-in-the-sky as there is pretty much zero chance of the 3rd/4th rail being extended north of Amersham.

If the Metropolitan Line extends to AVP then Chiltern operation would be restricted to a single platform at Aylesbury for the rump service via Princes Risborough.
There would be little need for it to to share platforms.

I'd say, even if it is unlikely, there is considerably more chance of the Met extending to Aylesbury than the Chiltern Main line receiving the well over billion pounds it would take to electrify.
Or the couple hundred million pounds required for reelectrification to Aylesbury via Amersham.

RailWonderer said:
? The 350/1 are dual voltage as are the 387s which both used it daily hassle free and currently the 700s use it day in day out with no issues at all.

It will require a fleet of dual voltage rolling stock to be provided which would otherwise not be required.

This will require additional maintenance work that would not be required otherwise, and place restrictions on diagramming that would not exist otherwise.

In addition, it would require electrical work on the LU to convert the line from four rail to de-facto third rail operation.

birchesgreen · 14 May 2024

Energy said:
Part of the Chiltern route used to be single track, how feasible is it to run a quiet mid-day service and revert to single track operation in sections with the other being used to pile for twin track cantilevers? I presume they don't have the required signaling.

There has been a massive increase in demand since then, its overcrowded for much of the time already never mind reducing the service for single track ops.

Electrifying the Snow Hill lines is going to be a long project, maybe doing it bit-by-bit with the current stock replaced by bi-modes. However they do it its going to be an expensive and long-term project (which probably means it's pretty unlikely to happen!)

As for the other end, i would have thought a lot of local Marylebone service could be fourth-rail units with batteries for the bits off of the shared-LU lines. You would need to upgrade the power supply though.

GRALISTAIR · 14 May 2024

cle said:
If Didcot-Oxford was wired, I would aim for Oxford first. That would mop up 3-4tph instantly.

I agree that wiring Didcot to Oxford is even higher priority than Chilterns. The major freight routes from the ports including Southampton need to be electrified and Didcot to Oxford is part of that. Then I would start at Marylebone and Birmingham end simultaneously.

Then do a Scotland and get grid feeders in place and do battery-electric hybrids to allow progressive electrification.

Bletchleyite · 14 May 2024

birchesgreen said:
There has been a massive increase in demand since then, its overcrowded for much of the time already never mind reducing the service for single track ops.

Though a good part of that is because people have been priced onto it. There is no guarantee a nationalised railway, as we look certain to have soon, will maintain that policy - indeed, it might choose to price people *off* Chiltern during the electrification process e.g. by removing the bargain Birmingham fares but leaving them there on "WMT" services, making Chiltern temporarily a local railway for local people.

GRALISTAIR said:
I agree that wiring Didcot to Oxford is even higher priority than Chilterns.

Agree, it was ridiculous that this was missed. Similarly, not wiring EWR from day one is stupid.

12LDA28C · 14 May 2024

HSTEd said:
If the Metropolitan Line extends to AVP then Chiltern operation would be restricted to a single platform at Aylesbury for the rump service via Princes Risborough.
There would be little need for it to to share platforms.

Clearly you're not familiar with operations at Aylesbury. Given the main Depot is located there, restricting Chiltern operations to a single platform is simply not practical.

Bletchleyite · 14 May 2024

12LDA28C said:
Clearly you're not familiar with operations at Aylesbury. Given the main Depot is located there, restricting Chiltern operations to a single platform is simply not practical.

The depot is there now but it doesn't have to stay there. You could build a new one adjacent to the mainline (designed to handle new, longer EMU stock) on farmland and turn that one into housing.

GRALISTAIR · 14 May 2024

Bletchleyite said:
Agree, it was ridiculous that this was missed. Similarly, not wiring EWR from day one is stupid.

I assume everyone agrees a massive grid -feeder (don't think you would need a Static Frequency Converter!!!) would be built at Claydon where there are plenty of powerlines and space IIRC?

12LDA28C · 14 May 2024

Bletchleyite said:
Agree, it was ridiculous that this was missed. Similarly, not wiring EWR from day one is stupid.

It was de-scoped to save money and yet according to this thread there would be funding in place to electrify the Chilterns which would be infinitely more difficult and expensive than wiring a brand new railway.

HSTEd · 14 May 2024

12LDA28C said:
Clearly you're not familiar with operations at Aylesbury. Given the main Depot is located there, restricting Chiltern operations to a single platform is simply not practical.

The depot is not required to be there forever, given that Chiltern's fleet would be shrinking significantly after it loses responsibility for the Aylesbury-via-Amersham line, you could just move the depot.
It's not a particularly extensive site as rail depots go.

Chiltern Main line electrification would likely lead to the construction of a new EMU depot anyway.

The best way to electrify the Chiltern Network and the Snow Hill Lines

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