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The 93 runs from Morden to North Cheam (having come from Putney Bridge and Wimbledon), not Sutton though. All the roads have a 20mph restriction, including the A24.
I mean the people living on the 93 route south of Morden station, as during the morning peak most of them already get off at Morden anyway. So building a tube station in Stonecot and North Cheam won't cause as much of a risk of overcrowding of the existing Northern line, because you'd just be picking up the same passengers who already get on at Morden anyway. The benefit comes from getting them off of the roads, which is desperately needed, because no traffic is travelling anywhere near 20mph on the A24 on a weekday morning.
People living in Sutton can already get to the Northern line at Balham or London Bridge or Elephant and Castle, and regardless can probably get to their destination in Central London quicker that way, rather than by any direct extension of the Northern line. Sutton is already well connected, so what is the point in an extension if it goes to (and through) areas already served by rail, to a terminus that has direct trains to the Northern line anyway?
Any tube extensions should really target rail deserts and major bus corridors (such as Bakerloo down Old Kent Road), which is why I think the Northern line would be better off going down the A24, instead of going to Sutton.
Any tube extensions should really target rail deserts and major bus corridors (such as Bakerloo down Old Kent Road), which is why I think the Northern line would be better off going down the A24 instead of going to Sutton.
Yes, presumably that is where it might have headed if has gone beyond Morden. I note that some passengers save a few pence by switching to the 93 at South Wimbledon rather than Morden.
Really needs a reversing arrangement in the middle of the formation rather than to one side, and even more one that doesn't involve having to check the train is vacated on arrival
More easily done at Southall as there is space. But I suspect any reversals in that area would be occasional rather than regular, after all Hayes is not too far away and they already have a bay platform to do just that movement.
Yes, presumably that is where it might have headed if has gone beyond Morden. I note that some passengers save a few pence by switching to the 93 at South Wimbledon rather than Morden.
I guess one thing against extending the Morden branch is that it wouldn't lead (as easily) to housing growth, given most of the area is already built up but just at low metroland-esque density. While improving PTAL is a noble goal, getting more housing in the area would involve a lot of demolishing and redevelopment, compared to something like the Battersea extension where there was lots of land ready to throw new blocks of flats and even skyscrapers up. Extensions leading to housebuilding will always rightly be prioritised.
Then again, at least they wouldn't have to pay for the land for a station at North Cheam as they could use the TfL sports ground land.
I mean the people living on the 93 route south of Morden station, as during the morning peak most of them already get off at Morden anyway. So building a tube station in Stonecot and North Cheam won't cause as much of a risk of overcrowding of the existing Northern line, because you'd just be picking up the same passengers who already get on at Morden anyway. The benefit comes from getting them off of the roads, which is desperately needed, because no traffic is travelling anywhere near 20mph on the A24 on a weekday morning.
People living in Sutton can already get to the Northern line at Balham or London Bridge or Elephant and Castle, and regardless can probably get to their destination in Central London quicker that way, rather than by any direct extension of the Northern line. Sutton is already well connected, so what is the point in an extension if it goes to (and through) areas already served by rail, to a terminus that has direct trains to the Northern line anyway?
Any tube extensions should really target rail deserts and major bus corridors (such as Bakerloo down Old Kent Road), which is why I think the Northern line would be better off going down the A24, instead of going to Sutton.
Sutton has always struck me as the natural destination for a Crossrail 2 branch taking over the western Thameslink loop (which would be split into a Wimbledon branch and a Sutton branch), offering either 2tph or 4tph into Central London. I like to imagine it getting it's own terminal platforms on the site of the old post office, north of the Mitcham-sutton-cheam-epsom Southern section.
Sutton has always struck me as the natural destination for a Crossrail 2 branch taking over the western Thameslink loop (which would be split into a Wimbledon branch and a Sutton branch), offering either 2tph or 4tph into Central London. I like to imagine it getting it's own terminal platforms on the site of the old post office, north of the Mitcham-sutton-cheam-epsom Southern section.
I think the Sutton Loop would be much easier fixed by just increasing to 4tph and terminating at Blackfriars, as per the original plan. Crossrail 2 will already have a lot of branches, I fear that interfacing with another set of lines, rather than being contained within South West metro area, would risk more disruption (e.g. as can easily happen with Thameslink currently)
I think the Sutton Loop would be much easier fixed by just increasing to 4tph and terminating at Blackfriars, as per the original plan. Crossrail 2 will already have a lot of branches, I fear that interfacing with another set of lines, rather than being contained within South West metro area, would risk more disruption (e.g. as can easily happen with Thameslink currently)
I actually agree - except that 4tph is still a pretty crappy service by the standards of most of London and is not going to get people to use rail as the default journey option for journeys where cars are also viable. I'd be more ambitious and do something like this: (And this by the way is an example of my earlier comment about putting in the infrastructure so you can run services as more separated frequent lines).
1. Swap things round at Herne Hill so the Blackfriars trains run to Bromley, and the Victoria trains to Sutton. This removes most conflicts - necessary for higher frequencies.
2. Rebuild Streatham Common station 300m further North - so it can have platforms on both the Victoria-Croydon and the Tulse Hill-Sutton lines.
3. Run a service every 10 minutes all stops Victoria -> Herne Hill->Streatham Common->Wimbledon->Sutton
4. AND a service every 10 minutes all stops Victoria -> Herne Hill->Streatham Common->Sutton->Epsom
These would become the only services along the Sutton->Tulse Hill corridor, with an easy interchange at Streatham Common for people who want trains towards Thornton Heath/Croydon or Clapham Junction.
Now with that service it would make a lot of sense to extend the Northern Line from Morden - but just one stop to St. Helier, from where you get the frequent connections to Sutton (or to Wimbledon).
This would also require corresponding changes to other routes. For example, in the Post-CR2 world, I've envisage the Dorking/Horsham services being entirely taken over by SWR/CR2 - which can provide a potentially quicker route into central London.
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I've tried to think on this - ostensibly slowing down every service to up frequency - and I think it's too difficult.
Victoria - Bromley South: you could have 6tph A pattern and 6tph B pattern - they make 3 calls before Bromley South. Herne Hill / Beckenham Junction as A/B. Or just hand it all to stoppers, at 10-12tph.
Charing Cross should then be used for outer services - it's quadded and can get to Swanley in the same time as from Victoria (less from London Bridge) - Bromley South is the main victim here, slowed down by 10 or so mins.
But overall - a tunnel to carry fast services to Bromley South - which branches off to East Croydon (underground station) - might enable more frequency within South London, which I agree is far more important, population-wise - and does worse than places like Sevenoaks.
Yes, a tunnel for the fast services to Bromley South is exactly what I would be thinking [*]. That would allow much better journey times Victoria->Bromley South on the fast trains, as well as (in conjunction with my Herne Hill suggestion) allowing much more frequent services towards Bromley: I'd suggest every 10 minutes Blackfriars->Herne Hill->Bromley South. The advantage of building a tunnel for the fast services over previous suggestions of building more tube lines is there are no underground stations involved (which as I understand it are the thing that really adds to the expense of tunneling).
[*] Actually in a post-CR2 world I'd tunnel from Bromley South not to Victoria but to Clapham Junction then Old Oak Common then link the fast trains from Kent with the Chiltern main line. But that's a whole other story for a different thread.
I actually agree - except that 4tph is still a pretty crappy service by the standards of most of London and is not going to get people to use rail as the default journey option for journeys where cars are also viable. I'd be more ambitious and do something like this: (And this by the way is an example of my earlier comment about putting in the infrastructure so you can run services as more separated frequent lines).
1. Swap things round at Herne Hill so the Blackfriars trains run to Bromley, and the Victoria trains to Sutton. This removes most conflicts - necessary for higher frequencies.
2. Rebuild Streatham Common station 300m further North - so it can have platforms on both the Victoria-Croydon and the Tulse Hill-Sutton lines.
3. Run a service every 10 minutes all stops Victoria -> Herne Hill->Streatham Common->Wimbledon->Sutton
4. AND a service every 10 minutes all stops Victoria -> Herne Hill->Streatham Common->Sutton->Epsom
These would become the only services along the Sutton->Tulse Hill corridor, with an easy interchange at Streatham Common for people who want trains towards Thornton Heath/Croydon or Clapham Junction.
Now with that service it would make a lot of sense to extend the Northern Line from Morden - but just one stop to St. Helier, from where you get the frequent connections to Sutton (or to Wimbledon).
This would also require corresponding changes to other routes. For example, in the Post-CR2 world, I've envisage the Dorking/Horsham services being entirely taken over by SWR/CR2 - which can provide a potentially quicker route into central London.
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Yes, a tunnel for the fast services to Bromley South is exactly what I would be thinking [*]. That would allow much better journey times Victoria->Bromley South on the fast trains, as well as (in conjunction with my Herne Hill suggestion) allowing much more frequent services towards Bromley: I'd suggest every 10 minutes Blackfriars->Herne Hill->Bromley South. The advantage of building a tunnel for the fast services over previous suggestions of building more tube lines is there are no underground stations involved (which as I understand it are the thing that really adds to the expense of tunneling).
[*] Actually in a post-CR2 world I'd tunnel from Bromley South not to Victoria but to Clapham Junction then Old Oak Common then link the fast trains from Kent with the Chiltern main line. But that's a whole other story for a different thread.
What’s your plan for Thameslink in this scenario? Do you envisage all trains from Loughborough Junction run through to Bromley South and beyond via Herne Hill? Would Bromley retain through services to Victoria via the Catford Line?
What’s your plan for Thameslink in this scenario? Do you envisage all trains from Loughborough Junction run through to Bromley South and beyond via Herne Hill? Would Bromley retain through services to Victoria via the Catford Line?
Essentially, yes. I'd rebuild Loughborough Junction slightly further South, so the trains from Victoria/Clapham Junction towards Denmark Hill can also stop there (so the resultant interchange removes the need for any trains from Blackfriars to run to Peckham Rye) and run a metro service Blackfriars -> Herne Hill -> Bromley South - also with a couple of new stations between Elephant and Castle and Loughborough Junction. Ideally that service would run every 7-8 minutes, but that's a bit dependent on sufficient capacity to terminate trains at Blackfriars. And yes, that would imply Catford line trains would run to Victoria. Add in some kind of tunnel for fast trains to Bromley South, so they don't need to go through Herne Hill, and that line would then be essentially isolated between Blackfriars and Beckenham Junction - ie. no conflicting moves with trains on any other routes.
Regarding tramlink to Sutton, this has been mentioned pretty much since the trams started in Croydon, so over 25 years. I travel a fair bit between Croydon and Sutton off-peak and the current four trains per hour are usually fairly empty, even those with only 4/5 carriages.
Unless my memory deceives me there was a period pre-2020 when there were more than four trains per hour on this route.
Over four miles of double track followed by just over a mile of single line track doesn't make sense to me. What’s the trouble with getting double track nearer the terminus?
Now with that service it would make a lot of sense to extend the Northern Line from Morden - but just one stop to St. Helier, from where you get the frequent connections to Sutton (or to Wimbledon).
I actually agree - except that 4tph is still a pretty crappy service by the standards of most of London and is not going to get people to use rail as the default journey option for journeys where cars are also viable. I'd be more ambitious and do something like this: (And this by the way is an example of my earlier comment about putting in the infrastructure so you can run services as more separated frequent lines).
1. Swap things round at Herne Hill so the Blackfriars trains run to Bromley, and the Victoria trains to Sutton. This removes most conflicts - necessary for higher frequencies.
2. Rebuild Streatham Common station 300m further North - so it can have platforms on both the Victoria-Croydon and the Tulse Hill-Sutton lines.
3. Run a service every 10 minutes all stops Victoria -> Herne Hill->Streatham Common->Wimbledon->Sutton
4. AND a service every 10 minutes all stops Victoria -> Herne Hill->Streatham Common->Sutton->Epsom
These would become the only services along the Sutton->Tulse Hill corridor, with an easy interchange at Streatham Common for people who want trains towards Thornton Heath/Croydon or Clapham Junction.
Now with that service it would make a lot of sense to extend the Northern Line from Morden - but just one stop to St. Helier, from where you get the frequent connections to Sutton (or to Wimbledon).
I'm not sure I understand the logic in extending the Northern Line to St. Helier? It's already not exactly a long journey to Wimbledon for other LU connections, and the Thameslink trains go via Elephant & Castle and London Bridge for Northern line access anyway. And if you wanted interchange with the Sutton Loop, surely Morden South would be the easier option as it's next to the existing depot?
An extension beyond/via St. Helier, that's a different matter altogether.
I feel like a lot of the Sutton loop chat is a solution looking for a problem. Look at the station usage - this is not a well used line. And these are low density areas.
You could try the 4tph plan and probably that is as good as it ever needs - and build some apartments alongside it. Even Sutton isn’t that busy, it’s a sleepy outer shopping street - and all it would really do is feed other (full) lines at Wimbledon.
Then again, Streatham, Tulse and Herne Hills - they would benefit from the frequency!
I feel like a lot of the Sutton loop chat is a solution looking for a problem. Look at the station usage - this is not a well used line. And these are low density areas.
Are the areas around the Thameslink station any lower density than around the nearby Underground stations? (genuine question, not sure how to find an answer).
I think part of the problem is induced demand, in that I think the 2tph is a big turnoff. If you live near Sutton it's not too bad if a train gets cancelled because you can travel "the wrong way" round the loop and the journey time isn't that different. But otherwise, say you just happen to miss a train, and the next service gets cancelled: that's an hour delay to your day. Or you could do what everyone else does and get a bus from past going straight past the nearby Thameslink station to e.g. Morden, Wimbledon, Brixton etc. where there's a train every few minutes. (I know someone who lives next to Loughborough Junction and never uses it, always walking past it to go to Brixton because they don't trust the Thameslink reliability, especially as the Loop services tend to be binned off first in the event of disruption)
People probably said similar things about the North London Line, and look at that now - if you build it, they will come.
I feel like a lot of the Sutton loop chat is a solution looking for a problem. Look at the station usage - this is not a well used line. And these are low density areas.
I visit this area a few times a year. As I'm travelling to and from the Fens, I mainly use Thameslink. I agree this is a solution looking for a problem.
Sutton has 10tph to/from central London. In addition to the Thameslink loop trains it has 4tph to/from Victoria and 2tph to/from London Bridge. The traffic is spread over more than one route and that isn't going to change.
There are also lots of local journeys to/from West Croydon and Epsom.
Thameslink has 4tph from all of these, and they are well used. Sometimes I get to see 27 minutes of evening peak while changing trains at Blackfriars, the Sutton loop trains are full and standing when they leave Blackfriars.
Build it and they will come is usually the last refuge for a proposal that doesn't have any sound economic justification. The North London line was very different because of the economic impact that it had on places like Dalston and Hackney, at a time when the London economy was growing much more strongly than now. People came to the North London Line because the economic circumstances generated the traffic, here the place and the time don't have the same economic characteristics.
Are the areas around the Thameslink station any lower density than around the nearby Underground stations? (genuine question, not sure how to find an answer).
I think part of the problem is induced demand, in that I think the 2tph is a big turnoff. If you live near Sutton it's not too bad if a train gets cancelled because you can travel "the wrong way" round the loop and the journey time isn't that different.
Throw in poor connection to other lines - for example from my neck-of-the-wood, change at Surbiton and Wimbledon where the connection to Thameslink is poor... it's typically a 20-25 minute connection (assuming a good service) although perversely a late-running Thameslink means the connection is much shorter!!)
I think the proposal, oft discussed, to extend each loop from Sutton back to Blackfriars (thus giving all stations on the loop 4tph each way, and 8tph between St Reatham and Blackfriars) makes sense - although this may impact/replace the Southeastern's peak into Blackfriars.
Nobody ever said the same thing about the North London Line. The North London Line was always busy, even in the days when it went to Broad Street. It had many other issues, but popularity was not one of them.
Wimbledon-Sutton is sparsely used because, in general, it is quicker to take the Northern Line from Morden. And it probably always will be.
Nobody ever said the same thing about the North London Line. The North London Line was always busy, even in the days when it went to Broad Street. It had many other issues, but popularity was not one of them.
Wimbledon-Sutton is sparsely used because, in general, it is quicker to take the Northern Line from Morden. And it probably always will be.
The Northern Line is quicker, but if you're travelling from near a Thameslink station to get to Morden, then it starts to become even money. In which case, the northern line has a huge frequency, and therefore convenience, advantage over Thameslink. If you double the frequency of the Thameslink, which I believe (although correct me if I'm wrong) wouldn't require any infrastructure work*, then suddenly the Thameslink becomes more appealing for those who already live near it but travel to LU instead. Especially for those who can go "either way" around the loop, they effectively now have an 8tph service.
*rolling stock would be an issue and would impact other Thameslink services, granted
Sutton is already well connected. Looking at the PTAL values, I think the (originally planned) extension down the A24 to North Cheam, via Morden South and Stonecot, would be a much better option for improving connectivity and reducing car usage.
Most of the people living in the area take the 93 bus to Morden anyway, so less of a risk of overcrowding as all you'd be doing is saving existing Northern Line passengers a bus ride.
TfL already own a large sports ground next to the Sainsburys, so that would cut down on costs if the side could be reused for a station.
Maybe you can just build a moving walkway from Morden South to Morden? Bus 164 is probably already quite good enough as it takes just 15 minutes from Sutton station to Morden and runs about 12 times/hour. However not sure if extending the Northern Line on Thameslink tracks would indeed be very costly or could it be a bit of a bargain compared to say extending the trams.
Maybe you can just build a moving walkway from Morden South to Morden? Bus 164 is probably already quite good enough as it takes just 15 minutes from Sutton station to Morden and runs about 12 times/hour. However not sure if extending the Northern Line on Thameslink tracks would indeed be very costly or could it be a bit of a bargain compared to say extending the trams.
I think extending the Northern Line down the loop would face the same problems of the trams: you have to somehow get them up onto the viaduct which would be Big civil engineering, you're replacing bigger trains with smaller ones, and it doesn't get you any new railway, just rejigging existing ones. If you just want an interchange with the Northern Line and the Loop, Morden South is probably the best (albeit still pretty infeasible*) place to do this, as it's next to the depot
The whole reason the Greenford trains no longer run into Paddington was to remove the capacity constraint of the flat crossing; ie they’d ‘mess with’ the through service on the up relief. It must follow that nobody will be interested in reinstating any sort of service pattern that has down trains crossing the up line, either to use West Ealing sidings, or to go towards Greenford.
It's not about frequency, it is about journey time. Thameslink is slow.
It is 50 minutes on the train from Morden South to St Pancras. It is 32 minutes on the train from Morden on the Northern Line then the Victoria Line to Kings Cross St Pancras.
It's not about frequency, it is about journey time. Thameslink is slow.
It is 50 minutes on the train from Morden South to St Pancras. It is 32 minutes on the train from Morden on the Northern Line then the Victoria Line to Kings Cross St Pancras.
Frequency is part of the door-to-door journey time though: the Thameslink is already slower *and* you have a 30 minutes wait for a train if one is cancelled or you just miss it, and at the moment that waiting time is longer than the journey to Morden. This explains why the stations on the Loop are some of the least used in Greater London.
I think if the frequency was improved, the convenience (with declassified first class too) could be enough to get people who are living closer to Loop stations than Morden to use TL instead - but at the moment the Northern line wins on every count.
My proposal is simply that by terminating in Blackfriars (and rejigging some other TL services so they can get enough of the 8-car trains), they can bump the frequency from 2tph to 4tph (effectively 8tph for the stations near Sutton, if you can go either way round the loop) - with no need for any new lines, so no complicated (and expensive) infrastructure costs. Seems like a quick win to me. Yes, terminating at Blackfriars would lose the direct connections to City Thameslink Farringdon and St Pancras, but it's a cross platform interchange anyway, so no more onerous than changing at Stockwell. (And if you don't live near Morden, you're already either having to walk or bus to Morden anyway.)
It just seems ludicrous to me that we have so many situations where people live nearer to NR stations, but it's still preferable to walk or bus to an LU station instead. (See also: Brixton)
You can’t. From Sutton, it is ten minutes slower via Wimbledon compared to via Mitcham.
The west side of the loop serves a local purpose but it is never going to be a viable alternative to the tube. It is too slow. Even if you’re standing at South Morden as a Thameslink pulls in, it is still quicker to walk to Morden and get the tube.
Terminating at Blackfriars wouldn’t improve things either. If you take those trains out of the core, how are you replacing the capacity out to St Albans?
I said stations near Sutton, but actually: for Sutton, West Sutton, Sutton Common, St Helier, and Morden South, on the timings of the current 2tph timetable, if you just miss a "shorter" train it's actually quicker to get the next "long" train than it is to wait 29 minutes for the next "short" one. (In fact at West Sutton it's always a quicker journey to """change""" at Sutton and go via MIJ, than it is to go """direct""" via WIM. At Sutton Common, its 45 minutes to Blackfriars either way around the loop).
With an increase to a 4tph timetable (so 8tph both ways) it's still only those stations Sutton<->Morden South where it's quicker to get the next train in any direction than wait for the "shorter" one. But, for the rest of the stations, at least your wait for your next best train is now only a maximum of 15 minutes, not 30.
The west side of the loop serves a local purpose but it is never going to be a viable alternative to the tube. It is too slow. Even if you’re standing at South Morden as a Thameslink pulls in, it is still quicker to walk to Morden and get the tube.
But if it's hammering down with rain or really late, and you live next to a Loop station, do you want to walk/bus/cycle to Morden and then ride a hot, crowded 95 stock the whole way? Or get on a nearer nicer TL train, with aircon, tables, probably a guaranteed seat given how quiet the line is, and declassified First Class? Sometimes (and I freely admit, certainly not always) convenience can outweigh quicker journey, within reason. In particular, if that journey involves a bus through the terrible traffic near Morden in rush hour...
Terminating at Blackfriars wouldn’t improve things either. If you take those trains out of the core, how are you replacing the capacity out to St Albans?
For that I will admit that I don't know enough about Thameslink to answer. But given that the original plan up to the eleventh hour was to terminate trains at Blackfriars, presumably something must have been in place to remedy St Albans?
For that I will admit that I don't know enough about Thameslink to answer. But given that the original plan up to the eleventh hour was to terminate trains at Blackfriars, presumably something must have been in place to remedy St Albans?
My proposal is simply that by terminating in Blackfriars (and rejigging some other TL services so they can get enough of the 8-car trains), they can bump the frequency from 2tph to 4tph (effectively 8tph for the stations near Sutton, if you can go either way round the loop) - with no need for any new lines, so no complicated (and expensive) infrastructure costs. Seems like a quick win to me.
The key feature of the Sutton loop is that it takes 45 minutes to go from Streatham South Junction round the loop and back to Streatham South Junction. This enables the 2tph timetable to be built on parallel moves at Streatham South Junction and Sutton.
At xx00/xx30 the trains going on and off of the Carshalton side of the loop have parallel moves at Streatham South Junction
At xx15/xx45 the trains going on and off of the Wimbledon side of the loop have parallel moves at Streatham South Junction
At xx15/xx45 clockwise and anticlockwise trains also do a parallel move at the west end of Sutton station going to and from Wimbledon
Furthermore, trains are almost evenly spaced going through the single track at Wimbledon.
With 4tph the parallel moves at Streatham South Junction can only be maintained by accelerating trains to go round the loop in 37 minutes, or retarding them to take 52 minutes. With a 45 minute running time and 4tph there will always be conflicting moves at Streatham South Junction for trains running anti-clockwise round the loop. Furthermore, it becomes impossible to space 8tph through the single platform at Wimbledon.
Was it? Interesting - so then why was there so much fuss kicked up at the time about losing through services beyond Blackfriars, if (some) of the trains were still going up through the core to St Albans? Uninformed local politicians? (I remember that the then MPs for Sutton and Wimbledon were particularly against it)
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The key feature of the Sutton loop is that it takes 45 minutes to go from Streatham South Junction round the loop and back to Streatham South Junction. This enables the 2tph timetable to be built on parallel moves at Streatham South Junction and Sutton.
At xx00/xx30 the trains going on and off of the Carshalton side of the loop have parallel moves at Streatham South Junction
At xx15/xx45 the trains going on and off of the Wimbledon side of the loop have parallel moves at Streatham South Junction
At xx15/xx45 clockwise and anticlockwise trains also do a parallel move at the west end of Sutton station going to and from Wimbledon
Furthermore, trains are almost evenly spaced going through the single track at Wimbledon.
With 4tph the parallel moves at Streatham South Junction can only be maintained by accelerating trains to go round the loop in 37 minutes, or retarding them to take 52 minutes. With a 45 minute running time and 4tph there will always be conflicting moves at Streatham South Junction for trains running anti-clockwise round the loop. Furthermore, it becomes impossible to space 8tph through the single platform at Wimbledon.
The single track at Wimbledon is a constraint yes, but I believe Tramlink are getting evicted when (if) Wimbledon is rebuilt for Crossrail 2, which could restore a second platform for Thameslink?
As for the junction fair enough, that does sound like a constraint - but once again, if that was the original plan 20 years ago, then has something changed between now and then that means this doesn't work? Furthermore I thought the current setup caused issues at the junctions on the approach to Blackfriars where the Loop trains cross over?
The Sutton trains have parallel moves at Blackfriars Junction too. Having trains terminating in the Blackfriars bays would create new conflicting moves.
For that I will admit that I don't know enough about Thameslink to answer. But given that the original plan up to the eleventh hour was to terminate trains at Blackfriars, presumably something must have been in place to remedy St Albans?
The Sutton trains have parallel moves at Blackfriars Junction too. Having trains terminating in the Blackfriars bays would create new conflicting moves.
if the Sutton Trains stayed on the Holborn Slows this would remove all conflicts with anything approaching the Core on the Fasts and the Sussex lines.
in any event very little crosses at Blackfriars Junction on the approach from Elephant & Castle Loughborough Junction & Southwark Bridge Junction are used in preference.
The most obvious contenders to take over the St Albans Services are the Sevenoaks/ Orpington services, both also 8 Car routes and neither operate North of Blackfriars/ Kentish Town in the off peak.
if they were to go through then the only moves from the Fasts to Slow would be the SE Peak Extras from Gillingham/ Maidstone.
