DLR double tracking Stratford to Bow Church

[Ronnie268]

There are various references to this supposedly happening by 2019 (see for instance https://www.london.gov.uk/transport/rail-and-underground/improving-londons-railways), but I'm struggling to find anything concrete.

All remaining single-track sections between Stratford and Bow Church will also be doubled, enabling a further increase in capacity between Stratford and Canary Wharf. This work is due for completion in 2019. The whole project will improve reliability and is essential to serving the growth and regeneration of the area.

Does anyone know if this is actually happening?

 

[Class 170101]

I don't think there is any space between Bow Church and the extended Pudding Mill Lane loop to the south. There looks to be space to the north towards Stratford.

 

[moogal]

I can only see this happening in the Bow Church - Pudding Mill Lane section if there's some modification to the mainline railway track alignments next to it so that everything moves northwards slightly.

There's certainly no room to the south of the line to build an extra track (and I say this with confidence because a few metres to that side of the current single track is my kitchen window!)

Pudding Mill Lane to Stratford looks more plausible but would require some bridge reconstruction which I imagine to be expensive - there's at least one bridge where each track is its own span.

 

[Blindtraveler]

Lucky sodd having that outside your window, jellus.

 

[plcd1]

There are various references to this supposedly happening by 2019 (see for instance https://www.london.gov.uk/transport/rail-and-underground/improving-londons-railways), but I'm struggling to find anything concrete.

Does anyone know if this is actually happening?

I can't recall seeing any funding paper going to a relevant TfL meeting. This is unlikely to be a cheap piece of work so it would probably need to go to the TfL Board. I wonder if there is a dependency on Crossrail being linked to the NR network at Stratford which might then allow track realignment to occur to the west of the XR portal. I think, but am not sure, that the Crossrail tracks will be linked in at Stratford over Christmas / New Year 2017. There is a week long blockade in the area (according to the TfL closures list, not yet on NR website).

 

[greatkingrat]

The last reference I can find to the scheme was in Jan 2016 (page 6) where they approved £3m for design work with an estimated completion date of May 2021.

 

[Tobbes]

I use this section every day, and I've often pondered this. At the Bow end, the tight climbing turn to the level of the GEML runs along a single track trace next to the link between the GEML and Limehouse on LT&SR. Presumably the gradient reflects that the DLR's predecessor passed north under the GEML heading for Old Ford(?) (https://www.google.co.uk/maps/place...9bafdae50f09e50!8m2!3d51.5340081!4d-0.0133586)

Doubling the DLR would mean building a second track south/east of the existing alignment, which would appear to require land take from gardens in Hartfield Terrace and Fairfield Road. Given the grass growing through the rails, I wonder how often this link is used? If it isn't used very much, would it be feasible to have a short section where it dual electrified (like Thameslink), minimising the additional land required.

 

[Chris M]

I use this section every day, and I've often pondered this. At the Bow end, the tight climbing turn to the level of the GEML runs along a single track trace next to the link between the GEML and Limehouse on LT&SR. Presumably the gradient reflects that the DLR's predecessor passed north under the GEML heading for Old Ford(?) (https://www.google.co.uk/maps/place...9bafdae50f09e50!8m2!3d51.5340081!4d-0.0133586)

Doubling the DLR would mean building a second track south/east of the existing alignment, which would appear to require land take from gardens in Hartfield Terrace and Fairfield Road. Given the grass growing through the rails, I wonder how often this link is used? If it isn't used very much, would it be feasible to have a short section where it dual electrified (like Thameslink), minimising the additional land required.

The link is used by a handful of ECS moves, some Christmas specials, and most significantly as a diversionary route, so simply handing it over to the DLR completely is not realistic.
Dual electrification is typically cited as expensive because things need to be double insulated, signalling needs to be immunised, etc. I don't know if this line is a track circuit area, but if so they would also be complicated.

The DLR does not currently share track with any other network, and there are three key things that would need to be sorted before it could:
1. Electrical compatibility
2. Gauging and infrastructure
3. Signalling

Looking at them in a bit more detail in turn:
Electrical compatibility - see above about complexities of dual electrified sections, but 25kv AC and 750v DC occur on the same stretches of railway in several places around the country so electrically I don't see any issues other than cost (but see next section).

Gauging and infrastructure - DLR stock is squarer that mainline stock, but similarly sized, and happily reuses old mainline infrastructure and runs parallel to NR metals, so the main bit of the train body is unlikely to cause significant problems, particularly as there are no tight tunnels or overbridges on this section AFAICR. However, the DLR uses a raised, bottom-contact third rail that stands about 2ft above rail level and the trains have a corresponding projecting pickup-shoe at this height. You would need to ensure that these do not foul the gauge of mainline trains - my guess would be that AC only units might be OK but units with conventional third rail gear would very likely not be.

Signalling - this is likely to be the biggest problem. DLR uses the SelTrac moving-block TBTC (Transmission Based Train Control) system. This is likely incompatible with the signalling system used on the rest of c2c.
Also, the DLR is driverless and fully automated in normal operation. I suspect that this is also incompatible with NR's present operations.

 

[Class 170101]

I use this section every day, and I've often pondered this. At the Bow end, the tight climbing turn to the level of the GEML runs along a single track trace next to the link between the GEML and Limehouse on LT&SR. Presumably the gradient reflects that the DLR's predecessor passed north under the GEML heading for Old Ford(?) (https://www.google.co.uk/maps/place...9bafdae50f09e50!8m2!3d51.5340081!4d-0.0133586)

Until the DLR was built the curve between Stratford and Bow Church did not exist and the link between Stratford and Limehouse was double track throughout. The DLR route at Bow Church headed north in (pre) BR days to Old Ford and Victoria Park. To enable the DLR to reach Stratford the link between Stratford and Limehouse was singled, removing what would have been the Up Line and using what was the Down line as a Bi-Directional Line, the Up formation was modified to allow the curve DLR now uses between Bow Church and Pudding Mill Lane.

 

[Tobbes]

Until the DLR was built the curve between Stratford and Bow Church did not exist and the link between Stratford and Limehouse was double track throughout. The DLR route at Bow Church headed north in (pre) BR days to Old Ford and Victoria Park. To enable the DLR to reach Stratford the link between Stratford and Limehouse was singled, removing what would have been the Up Line and using what was the Down line as a Bi-Directional Line, the Up formation was modified to allow the curve DLR now uses between Bow Church and Pudding Mill Lane.

Thanks, that's very interesting.