Where next to four track?

[Jorge Da Silva]

Could the section between Bristol and Parson Street be worth four-Tracking?

 

[Esker-pades]

Could the section between Bristol and Parson Street be worth four-Tracking?

It's already 3 track (2 up, 1 down) plus the Bedminster siding. I don't think there would be much point adding more tracks.

 

[4-SUB 4732]

Should be possible from Huntingdon to Holme and then Yaxley to Peterborough itself, across Stilton Fen itself would require a lot of work.

As to Cambridge to Shepreth Junction, the sooner they get on with this the sooner the capacity is there to improve the service ie you can separate GA and GTR services as each would be using their designated tracks as one pair of tracks would be for West Anglia bound services and the other pair will be for Great Northern bound services.

And even more important when East West cuts in under Mill Road / Hills Road (never remember which bridge is which) to have more capacity.

 

[AndrewE]

It's already 3 track (2 up, 1 down) plus the Bedminster siding. I don't think there would be much point adding more tracks.

As Temple Meads has 8 through platforms serving 5 tracks eastbound - splitting into 4 for Parkway and 2 for Bath, plus 3 westbound feeding into 2 when you get further out (past Malago Vale?) I can't see any real need for it either, unless you have trains ready to go with no track available.
I have noticed on open train times http://www.opentraintimes.com/maps/signalling/crewe#T_CREWE that Crewe S Junction has been reduced to 3 lines - the first pinch point on the WCML going north! (or last going south.) I would think that extending the line south out of pfm 5 would allow us to get a train away past the Carriage Sheds towards the up fast in the event of something running late on the up through line. It would save delaying the departing train and release the platform for the next up train as well.

 

[Bald Rick]

I have noticed on open train times http://www.opentraintimes.com/maps/signalling/crewe#T_CREWE that Crewe S Junction has been reduced to 3 lines - the first pinch point on the WCML going north! (or last going south.) I would think that extending the line south out of pfm 5 would allow us to get a train away past the Carriage Sheds towards the up fast in the event of something running late on the up through line. It would save delaying the departing train and release the platform for the next up train as well.

It was ‘reduced’ a third of a century ago!

It would be difficult to get a extra line out of P5 alongside the Carriage sheds, as it would cause issues with the junctions to the Alsager route, which would either reduce the routes available to / from Alsager, or the linespeeds through the junctions, or most probably both.

 

[MarkyT]

As Temple Meads has 8 through platforms serving 5 tracks eastbound - splitting into 4 for Parkway and 2 for Bath, plus 3 westbound feeding into 2 when you get further out (past Malago Vale?) I can't see any real need for it either, unless you have trains ready to go with no track available.
I have noticed on open train times http://www.opentraintimes.com/maps/signalling/crewe#T_CREWE that Crewe S Junction has been reduced to 3 lines - the first pinch point on the WCML going north! (or last going south.) I would think that extending the line south out of pfm 5 would allow us to get a train away past the Carriage Sheds towards the up fast in the event of something running late on the up through line. It would save delaying the departing train and release the platform for the next up train as well.

At Crewe, don't forget a significant proportion of traffic using the slows already peels off to the 'independents' and yards at Basford Hall Junction. Crewe South is also where (going north) a 'paired by use' arrangement transitions to 'paired by direction' through the station, except for down trains terminating on the up side or up passenger services coming from Chester to the slows. Hence the small section of 3-track infrastructure is no big problem, as most other up passenger trains heading to the slows would have to cross both fasts anyway.

At Bristol a case for four tracks from Bristol TM going west as far as Parson Street might be made primarily to create a 'right turn lane' for freight going to Portbury and the Freightliner terminal, and any future passenger services heading for Portishead. While waiting for a path across the Up Main such trains could be overtaken by Down expresses, and indeed they could move across the junction in parallel with such through movements simultaneously. The old carriage line serving former Malago Vale and West Depot sidings could largely form the alignment for this new Down Main line as far as Parson Street, passing around the outside of the down island platforms there and at Bedminster. The carriage line can be seen in this sketch depicting what was still extant in 1988.
http://bristol-rail.co.uk/wiki/File:Parson_Street_Track_Plan_1988.jpg

 

[Aictos]

What about:

Grantham to Doncaster
Doncaster to Leeds

Grantham to Doncaster as instead of keeping having to loop freights you can keep them moving and Doncaster to Leeds as you can improve the local services and the long distance services by proxy by not having one slow down the other as they be using separate tracks you could even increase the number of services.

 

[trainmania100]

Three bridges to Brighton would be good although there's a small handful of people that would prefer to have a BML2
Four tracking three bridges to Brighton would be VERY expensive as there are a few tunnels that would need expanding, the historical Clayton tunnel, patcham, Haywards heath and balcombe tunnel.
I don't think four tracking Ouse valley viaduct would work either without a serious cash investment

 

[MarkyT]

What about:

Grantham to Doncaster
Doncaster to Leeds

Grantham to Doncaster as instead of keeping having to loop freights you can keep them moving and Doncaster to Leeds as you can improve the local services and the long distance services by proxy by not having one slow down the other as they be using separate tracks you could even increase the number of services.

I thought the idea was to allow more ECML freights to use the GN & GE Joint Line by way of the Werrington Junction grade separation. That would effectively create four tracks by means of a parallel and otherwise underutilised existing route.

 

[Ken H]

I thought the idea was to allow more ECML freights to use the GN & GE Joint Line by way of the Werrington Junction grade separation. That would effectively create four tracks by means of a parallel and otherwise underutilised existing route.

GN&GE isnt really up to it. Its stuffed with level crossings. Some more ECML 4 tracking would help enormously. And of course, the Newark flyover.

 

[DavidGrain]

I have heard talk of 4 tracking Birmingham to Coventry on a few occasions over the years and others more knowledgeable than I have made comments above. What I can say is that back in 1974 I had a discussion with the then chairman of the NEC which had not been built at that stage. He said that the plan was to have three expresses to London per hour. I then questioned him on capacity on the line and he said that the plan was to have the expresses overtake the locals at the new station which would be shared between the NEC and the airport. I was informed that the new station would have 5 platforms

At that time I do not think that the present Cross Country services took that route so that is an increase since then. Also we did not have the TfW services terminating at International.

My question is Do any trains overtake at international? I used to travel on the Wrexham and Shropshire Railway which had a forced wait at International to allow a Virgin to overtake. I also recall that a Birmingham to Coventry local at one time had a wait of about 5 minutes for a North of London Eurostar to overtake even although they never actually ran. Last time I was at International all the platforms except no. 5 seemed fairly busy and even a freight train went through

 

[MarkyT]

Three bridges to Brighton would be good although there's a small handful of people that would prefer to have a BML2
Four tracking three bridges to Brighton would be VERY expensive as there are a few tunnels that would need expanding, the historical Clayton tunnel, patcham, Haywards heath and balcombe tunnel.
I don't think four tracking Ouse valley viaduct would work either without a serious cash investment

Indeed, it's a bit of a 'Welwyn' sized problem, and a heritage challenge too as "probably the most elegant viaduct in Britain." Also I don't believe a lack of four tracks throughout is the Brighton Line's most pressing problem. A bit of stopping pattern adjustment could help significantly and grade separation closer to London, as planned in spadeloads for the Croydon area.

 

[Bald Rick]

What about:

Grantham to Doncaster
Doncaster to Leeds

Grantham to Doncaster as instead of keeping having to loop freights you can keep them moving and Doncaster to Leeds as you can improve the local services and the long distance services by proxy by not having one slow down the other as they be using separate tracks you could even increase the number of services.

GN&GE isnt really up to it. Its stuffed with level crossings. Some more ECML 4 tracking would help enormously. And of course, the Newark flyover.

GN / GE is very much up to it, as rather a lot of cash has been spent to make it so, including upgrading many of the level crossings. In any event very little freight uses the ECML proper.

 

[Ianno87]

I have heard talk of 4 tracking Birmingham to Coventry on a few occasions over the years and others more knowledgeable than I have made comments above. What I can say is that back in 1974 I had a discussion with the then chairman of the NEC which had not been built at that stage. He said that the plan was to have three expresses to London per hour. I then questioned him on capacity on the line and he said that the plan was to have the expresses overtake the locals at the new station which would be shared between the NEC and the airport. I was informed that the new station would have 5 platforms

At that time I do not think that the present Cross Country services took that route so that is an increase since then. Also we did not have the TfW services terminating at International.

My question is Do any trains overtake at international? I used to travel on the Wrexham and Shropshire Railway which had a forced wait at International to allow a Virgin to overtake. I also recall that a Birmingham to Coventry local at one time had a wait of about 5 minutes for a North of London Eurostar to overtake even although they never actually ran. Last time I was at International all the platforms except no. 5 seemed fairly busy and even a freight train went through

Not normally no, although it is sometimes used during disruption. The odd freight paths etc down there do get overtaken IIRC.

Basic problem with planned overtaking of passenger services is that a Pendolino (the overtaker) requires a 2 minute dwell time, and we want them all to stop (as International justifies it easily).

A stopper (the overtake-ee) needs to arrive 3 minutes' headway before and 3 minutes' headway after... so a total dwell time of 8 minutes!

In any case, two of the 'stoppers' each hour only call at Marston Green between New Street and International, so overtaking them is of little value.

 

[MarkyT]

Basic problem with planned overtaking of passenger services is that a Pendolino (the overtaker) requires a 2 minute dwell time, and we want them all to stop (as International justifies it easily). A stopper (the overtake-ee) needs to arrive 3 minutes' headway before and 3 minutes' headway after... so a total dwell time of 8 minutes!

From a signalling perspective it might be possible to close the two trains up a bit as the following express catches up the local, and this may actually happen in real time if the local is a little delayed. Relying on being able to do that in normal operation is a recipe for passing on delay to the express however so is not allowed in planning. It's simply not robust enough. So it's eight minutes minimum planned dwell for the local if being overtaken. A better solution would be to split the local service so an 'inner tier' terminates at International and an 'outer tier' runs limited stop to International then all local calls to Coventry.

 

[Bald Rick]

A better solution would be to split the local service so an 'inner tier' terminates at International and an 'outer tier' runs limited stop to International then all local calls to Coventry.

Which is effectively what happens!

 

[Aictos]

Which is effectively what happens!

Unless of course somehow the LNWRs to London Euston run fast between Birmingham New Street and Birmingham International and leave the small stations in between to a stopper however saying that, the current situation although not perfect actually works so I think it ought to stay as it is.

I do think that the GEML needs to be done but it's either not possible or it's going to be very difficult unless I've misjudged the line bearing in mind I am not a user of it.

 

[Bald Rick]

Unless of course somehow the LNWRs to London Euston run fast between Birmingham New Street and Birmingham International and leave the small stations in between to a stopper however saying that, the current situation although not perfect actually works so I think it ought to stay as it is.

I do think that the GEML needs to be done but it's either not possible or it's going to be very difficult unless I've misjudged the line bearing in mind I am not a user of it.

Anything is possible, within the bounds of the laws of physics. However the laws of economics also have a say in the matter...

 

[Aictos]

Anything is possible, within the bounds of the laws of physics. However the laws of economics also have a say in the matter...

True and I think the two lines that ought to be done are the West Anglia Mainline and the Great Eastern Mainline, one to cater for Crossrail 2 and the other to increase capacity on the line.

 

[Bald Rick]

True and I think the two lines that ought to be done are the West Anglia Mainline and the Great Eastern Mainline, one to cater for Crossrail 2 and the other to increase capacity on the line.

4 tracking the GE doesn’t do much for capacity - where do you put the extra trains?

 

[Aictos]

4 tracking the GE doesn’t do much for capacity - where do you put the extra trains?

For one would it not help Norwich in 90?

 

[krus_aragon]

Dore to Sheffield was 4 track from 1993 until the 1960s.

That's what happens when you set the new series of Doctor Who in Sheffield.

 

[Bald Rick]

For one would it not help Norwich in 90?

It would help that, but that’s a lot of money to pay for a couple of minutes journey time.

 

[Killingworth]

That's what happens when you set the new series of Doctor Who in Sheffield.

Good spot 1903

 

[Aictos]

It would help that, but that’s a lot of money to pay for a couple of minutes journey time.

Okay well would it not help existing services on the line?

As to where next to four track I have a question for you and others, what routes could if doubled or quad tomorrow if the means was there would see the most benefit of doing so?

 

[Train Maniac]

Not entirely sure if its feasible but Dartford to to Gravesend would be handy, especially with the future Crossrail exstension proposed
Perhaps even harder to achieve, but would be of use, Strood to Rainham to give Thameslink services a bit more space

 

[DynamicSpirit]

Not entirely sure if its feasible but Dartford to to Gravesend would be handy, especially with the future Crossrail exstension proposed
Perhaps even harder to achieve, but would be of use, Strood to Rainham to give Thameslink services a bit more space

What would the benefit of Strood to Rainham be? Usually, the benefit of 4-tracking is that it allows fast trains to overtake slow trains. But since every train stops at every station between Strood and Rainham, there's no need for anything to overtake, so I'm struggling to see why you'd want to 4-track there.

 

[Bonshakerbrown]

4 tracking the GE doesn’t do much for capacity - where do you put the extra trains?

On the slow lines maybe ?

 

[Train Maniac]

What would the benefit of Strood to Rainham be? Usually, the benefit of 4-tracking is that it allows fast trains to overtake slow trains. But since every train stops at every station between Strood and Rainham, there's no need for anything to overtake, so I'm struggling to see why you'd want to 4-track there.

(shrugs) More capacity? Either that or segregation of services so less conflicting paths?

 

[Bald Rick]

On the slow lines maybe ?

I meant, where do they terminate?