Could the DLR be extended to Waterloo to replace the Waterloo and City Line?

[ijmad]

That I don't know.

The driving duty is rostered from Central Line drivers (the stock is very similar) but the maintenance is separate by necessity, as there's no way (aside from the crane) for the stock to get to any other depot. I don't know if maintenance staff are shared between the W&C and Central Line.

The automatic reversals are pretty snappy in the single turnback. Can do platform to platform in less than 2 minutes, when the service frequency is something like 24tph (6 Beckton, 12 Lewisham, 6 Woolwich) or something like that?

The limiting factor becomes a people problem: whether you can get people away from the train quick enough before the next one comes in. Major pinch points include whether there's enough space on the platform itself, the platform's empty rate (which depends on exits and escalators), how quickly a train full of passengers can get out through the train's doors, and whether they can move away from the doors quick enough to let the next load of passengers off in the train behind them.

I believe current DLR stock doesn't have enough door capacity per carriage to empty quick enough to allow much more than the current service to be emptied at Bank, and Bank itself has capacity problems meaning there may be problems getting people off the platforms, although they're currently working on that with the massive expansion there.

The CAF stock will have 13 double doors per side (2+3+3+3+2) compared to the current stock's eight.

But an extension so some other popular interchange destinations (Charing Cross, Green Park, Victoria or Holborn, Euston, St Pancras) would spread people out and allow you to run more trains per hour. Of course, the Elizabeth Line should release considerable capacity on the DLR too, as many people will choose to change at Custom House, change their journey to start from Woolwich Crossrail, or change to Crossrail at Canary Wharf rather than head into Bank.

 

[Ianno87]

This is why an extension so some other popular interchange destinations (Charing Cross, Green Park, Victoria or Holborn, Euston, St Pancras) would spread that out and allow you to run more trains per hour.

Although you wouldn't want to accidentally make it really popular for a journey like Victoria-Bank and add to, rather than reduce the congestion problem!

 

[ijmad]

Although you wouldn't want to accidentally make it really popular for a journey like Victoria-Bank and add to, rather than reduce the congestion problem!

True, although every passenger that continues to get off at Bank creates a space for another to go to Victoria. Bank would likely still attract a large portion of passengers even from an extended DLR.

 

[DynamicSpirit]

(especially as there's talk of closing Tower Gateway station to allow more space for Fenchurch St).

Is there? Who by? Do you mean serious talk about it, or speculation by rail enthusiasts?

But could Bank cope with the full service terminating there, having only one place to reverse? Yes, there are 2 platforms, but trains can't arrive at and leave from both, as in most such situations. Remember one is arrivals and one departures, with just one track to shunt into for reversing direction.

I would have thought so. Bank sees a service every 5 minutes to Lewisham and a service every 10 minutes to Woolwich. I believe what you'd be adding would be a service every 10 minutes to Beckton - presumably, that could fit in the 5 minute gaps when there isn't a Woolwich service.

In terms of capacity at Bank - isn't Bank station currently being rebuilt precisely in order to address capacity?

 

[ijmad]

Is there? Who by? Do you mean serious talk about it, or speculation by rail enthusiasts?

Have a read of https://www.ianvisits.co.uk/blog/2020/08/18/fenchurch-street-station-may-need-to-move/
It's a real proposal from Network Rail's Essex Thameside report.

I would have thought so. Bank sees a service every 5 minutes to Lewisham and a service every 10 minutes to Woolwich. I believe what you'd be adding would be a service every 10 minutes to Beckton - presumably, that could fit in the 5 minute gaps when there isn't a Woolwich service.

In terms of capacity at Bank - isn't Bank station currently being rebuilt precisely in order to address capacity?

The peak time DLR service is 30tph between Shadwell and Westferry, of which 22.5tph go to Bank (from Lewisham 15tph, from Woolwich 7.5tph) and 7.5tph go to Tower Gateway (from Beckton). It's an open question as to whether a full 30tph service could be emptied at Bank. They are improving the station but can that many passengers get out the doors of a DLR train in time for it to close down and clear the platform ahead of the one behind it? Perhaps with the CAF stock that has more doors, it's possible. By the time this Fenchurch Street and Tower Gateway rebuild happens I suspect the DLR will be looking seriously at westwards expansion anyway, which will spread out passenger disembarkation.

Even a DLR station at Tower Hill would do that, as it'd provide more convenient interchange with the Circle/District than Bank does.

 

[Ianno87]

Have a read of https://www.ianvisits.co.uk/blog/2020/08/18/fenchurch-street-station-may-need-to-move/
It's a real proposal from Network Rail's Essex Thameside report.




The peak time DLR service is 30tph between Shadwell and Westferry, of which 22.5tph go to Bank (from Lewisham 15tph, from Woolwich 7.5tph) and 7.5tph go to Tower Gateway (from Beckton). It's an open question as to whether a full 30tph service could be emptied at Bank. They are improving the station but can that many passengers get out the doors of a DLR train in time for it to close down and clear the platform ahead of the one behind it? Perhaps with the CAF stock that has more doors, it's possible. By the time this Fenchurch Street and Tower Gateway rebuild happens I suspect the DLR will be looking seriously at westwards expansion anyway, which will spread out passenger disembarkation.

Even a DLR station at Tower Hill would do that, as it'd provide more convenient interchange with the Circle/District than Bank does.

Having trains to Bank call at a Tower Hill station en-route would at least lose some of the passenger load before reaching Bank.

 

[ijmad]

Having trains to Bank call at a Tower Hill station en-route would at least lose some of the passenger load before reaching Bank.

Perhaps you missed the last line of my post

But yes, certainly agreed that might be all that's needed if a high quality connection for passengers continuing West could be provided.

 

[swt_passenger]

For those who missed it we had a thread about the Fenchurch St proposal about 3 weeks ago, triggered by the article on “ianvisits” mentioned earlier:

https://www.railforums.co.uk/threads/possibility-of-moving-fenchurch-street.207985/#post-4727330

 

[stuu]

Even a DLR station at Tower Hill would do that, as it'd provide more convenient interchange with the Circle/District than Bank does.

Bank DLR to Monument isn't very far or complicated, I would be surprised if any new underground platforms at Tower Hill could be significantly better an interchange

 

[ijmad]

Bank DLR to Monument isn't very far or complicated, I would be surprised if any new underground platforms at Tower Hill could be significantly better an interchange

That assumes that the transport planners wouldn't make the Bank/Monument interchange more inconvenient to push passengers down the new route.

A few one way signs and suddenly that 5 minute interchange becomes 15.

 

[stuu]

That assumes that the transport planners wouldn't make the Bank/Monument interchange more inconvenient to push passengers down the new route.

A few one way signs and suddenly that 5 minute interchange becomes 15.

Unlikely though, it's not like Kings Cross where there is more than one possible route. From the DLR (as I'm sure you know), you can go towards the rest of Bank, or directly to Monument, there isn't a more circuitous route that takes you back to the circle line

 

[DerekC]

I think the 3D layout below (sorry for the poor quality) shows that sadly this isn't going to work. The connection between the end of the DLR platforms and the W&C would be on what I think even for DLR vehicles would be an impossibly tight curve.

 

[stuu]

I think the 3D layout below (sorry for the poor quality) shows that sadly this isn't going to work. The connection between the end of the DLR platforms and the W&C would be on what I think even for DLR vehicles would be an impossibly tight curve.

It's also 20m lower and the tunnels are far too small anyway. So the curve is pretty much moot, but thanks for sharing the diagram

 

[markymark2000]

I think the 3D layout below (sorry for the poor quality) shows that sadly this isn't going to work. The connection between the end of the DLR platforms and the W&C would be on what I think even for DLR vehicles would be an impossibly tight curve.

View attachment 83296

You wouldn't keep both platforms, you would keep one or the other. I think you would be best keeping the DLR platforms and by the time you have got rid of the W&C line stuff, you would be boring a tunnel from the DLR eastern end to roughly the same place as the scissor points on the W&C line (with the curve basically intersecting across where the platform is currently.

You would be silly to keep both platforms.

 

[ijmad]

You're gonna have to re-bore the tunnels to the larger DLR profile anyway, so it's not like it'd need to re-use every bit of the existing infrastructure. As long as you could gradually turn and descent to reach the W&C alignment eventually, and then roughly follow its path to Waterloo, you could perhaps re-use the Waterloo W&C platforms and turnback. It's rather conveniently situated for interchange with the mainline after all. Put a station at Blackfriars halfway as well!

Since new tunnels are to be bored, I suppose the advantages of following the existing ones are somewhat less spoil to remove (although the existing tunnel rings would need to be removed) and you'd have an easier time working out what you might run in to along the way.

I wonder though, if it'd be any cheaper than just building entirely new tunnels nearby, and giving over the existing W&C tunnels to sewers or cables.

 

[Ianno87]

Bank DLR to Monument isn't very far or complicated, I would be surprised if any new underground platforms at Tower Hill could be significantly better an interchange

It would still be more convenient for the offices in that area and lightening the load at Bank. Depending on the station's depth/size it may also be quicker to reach the street from Bank.

 

[DynamicSpirit]

Have a read of https://www.ianvisits.co.uk/blog/2020/08/18/fenchurch-street-station-may-need-to-move/
It's a real proposal from Network Rail's Essex Thameside report.

Thanks, that's interesting.

The peak time DLR service is 30tph between Shadwell and Westferry, of which 22.5tph go to Bank (from Lewisham 15tph, from Woolwich 7.5tph) and 7.5tph go to Tower Gateway (from Beckton). It's an open question as to whether a full 30tph service could be emptied at Bank. They are improving the station but can that many passengers get out the doors of a DLR train in time for it to close down and clear the platform ahead of the one behind it?

Isn't it still the same reasoning as for off-peak? I'm guessing at Bank, those frequencies translate into a train from Lewisham every 4 minutes and a train from Woolwich every 8 minutes. So the additional trains (from Beckton) would simply slot into the 4-minute gaps where there is no Woolwich train. If the station can cope with 2-minute gaps between Woolwich and Lewisham trains, than presumably it can equally cope with 2-minute gaps between Beckton and Lewisham trains. There'd also be some smoothing out of flows - particularly for boarding at Bank - since people heading for stations between Poplar and Canning Town would be looking at a train every 4 minutes rather than every 8 minutes. You would however lose any operational flexibility to deal with delays that the current 4-minute gaps provide - maybe that's significant?

One other factor is that once Crossrail opens, that a lot of the people currently on the DLR - particularly the Woolwich and Beckton routes - will be on Crossrail instead.

== Doublepost prevention - post automatically merged: 9 Sep 2020 ==

Having trains to Bank call at a Tower Hill station en-route would at least lose some of the passenger load before reaching Bank.

Is it possible to build a station at Tower Hill on the DLR Bank branch? When I've been on the DLR, the impression I've had is that as soon as the line diverges from the Tower Gateway line, it descends continuously and steeply. You'd need a level bit to build platforms on.

 

[stuu]

Is it possible to build a station at Tower Hill on the DLR Bank branch? When I've been on the DLR, the impression I've had is that as soon as the line diverges from the Tower Gateway line, it descends continuously and steeply. You'd need a level bit to build platforms on.

There is a flat section of the tunnel intentionally for a station at Tower Hill/Gateway

 

[ashkeba]

You wouldn't keep both platforms, you would keep one or the other. I think you would be best keeping the DLR platforms and by the time you have got rid of the W&C line stuff, you would be boring a tunnel from the DLR eastern end to roughly the same place as the scissor points on the W&C line (with the curve basically intersecting across where the platform is currently.

It looks like it would be better to diverge from the current tunnels near Monument station and run through new platforms to join the W&C under the junction of Cannon Street and Queen Victoria Street: less curve, more distance to change height and would allow the current platforms to be used for operational issues.

But the W&C tunnels size remains an expensive problem.

 

[ijmad]

To put it into perspective, DLR tunnels to Bank are 5.3m diameter, whereas tube tunnels are around 3.6m. This is 22.0 sq metres vs 10.2 sq metres, so if you re-bore to widen them to DLR standard, you're going to have to still remove more than half of the material compared to just boring new tunnels, plus remove the existing tunnel rings, cables, rails, and anything else down there after all this time, including possibly hazardous particulate build-up that hasn't been disturbed in a century or more.

One wonders if that would ever be cost effective vs abandoning the existing tunnels and building brand new.

 

[DynamicSpirit]

Thinking more about this, if you want to extend the DLR, I wonder if Moorgate would be the best option. Much cheaper than almost anything else because you don't need to change the alignment or build new platforms at Bank. Relieves the Northern line over a short but (in my experience) exceptionally busy section. Provides interchange with Crossrail, and the northern part of the Circle/etc. lines for people heading further West and (less usefully) with Great Northern. I don't think there are any obstacles in the way. And you have the option of further extension to Euston if more money becomes available.

 

[ijmad]

Thinking more about this, if you want to extend the DLR, I wonder if Moorgate would be the best option. Much cheaper than almost anything else because you don't need to change the alignment or build new platforms at Bank. Relieves the Northern line over a short but (in my experience) exceptionally busy section. Provides interchange with Crossrail, and the northern part of the Circle/etc. lines for people heading further West and (less usefully) with Great Northern. I don't think there are any obstacles in the way. And you have the option of further extension to Euston if more money becomes available.

An extension from Bank to Moorgate and Farringdon was considered in the DLR Horizons 2020 Study. Some of the possibility there has now been lost now by Barbican's Crossrail ticket office blocking the widened lines, but even taking the extension just to Barbican would provide more interchange options, including the Northern Line, Great Northern train services, the Circle, Met, H&C, and Crossrail.

 

[markymark2000]

But the W&C tunnels size remains an expensive problem.

Oh, I fully agree. It's more a case of if you can solve the other problems as cheaply as possible, it means the project is more likely to make sense cost wise. IF you have a pot of £30m, you don't want to spend £10m on some things which could have been sorted a lot cheaper and vastly brought down the time of completion. This then leaves less money for the main project which in this case is the tunnel size.

To put it into perspective, DLR tunnels to Bank are 5.3m diameter, whereas tube tunnels are around 3.6m. This is 22.0 sq metres vs 10.2 sq metres, so if you re-bore to widen them to DLR standard, you're going to have to still remove more than half of the material compared to just boring new tunnels, plus remove the existing tunnel rings, cables, rails, and anything else down there after all this time, including possibly hazardous particulate build-up that hasn't been disturbed in a century or more.

One wonders if that would ever be cost effective vs abandoning the existing tunnels and building brand new.

Do you need 5.3m diameter as the DLR does have emergency evacuation via the front and rear of the rain so it could surely just act as a tube line in that respect where any incident would have passengers walk along the track. DLR runs off 3rd rail so the four foot is actually safer on the DLR than tube in terms of emergency evacuation. This then would mean you are just boxing off the tunnel from the widest point, upwards (until you hit the desired height)




I would like to say that I know there are lots of possibilities for DLR extensions, I just wanted to make this thread specifically about the service replacing the W&C line rather than extensions which would be much bigger projects.

 

[stuu]

I would like to say that I know there are lots of possibilities for DLR extensions, I just wanted to make this thread specifically about the service replacing the W&C line rather than extensions which would be much bigger projects.

The fact is that spending hundreds of millions of pounds replacing one service with a very similar service is not the best use of money. If funding is available then extend the DLR somewhere else, then there is new link somewhere and the W&C still exists - so the network is improved

 

[Bald Rick]

Do you need 5.3m diameter as the DLR does have emergency evacuation via the front and rear of the rain so it could surely just act as a tube line in that respect where any incident would have passengers walk along the track.

Yes, because not everyone can walk.

 

[ijmad]

Do you need 5.3m diameter as the DLR does have emergency evacuation via the front and rear of the rain so it could surely just act as a tube line in that respect where any incident would have passengers walk along the track. DLR runs off 3rd rail so the four foot is actually safer on the DLR than tube in terms of emergency evacuation. This then would mean you are just boxing off the tunnel from the widest point, upwards (until you hit the desired height)

Even if you could somehow convince the regulators to waive the escape walkway for this project, drawing a circle around a DLR train's loading gauge diagram suggests you'd need a tunnel at least 4.4m in diameter, which is still considerably bigger than your 3.6m W&C. So you'd still need to re-bore.

i did a diagram, red is the 3.6m size, orange is 4.4m, and green is 5.3m:

 

[markymark2000]

Yes, because not everyone can walk.

The tube doesn't have walkways, nor does Merseyrail or plenty of other underground areas of railway. I'd say it's a 50/50 split between areas with and areas without a walkway.

 

[Bald Rick]

The tube doesn't have walkways, nor does Merseyrail or plenty of other underground areas of railway. I'd say it's a 50/50 split between areas with and areas without a walkway.

None of which were built after 1990, and none of which are fully accessible from street to train, which the DLR is.