Goblin Electrification info

I wonder if its simply that installing masts on platforms requires different equipment/tools/processes/something than installing them trackside? If so then it might be that doing all the trackside bits in one go first and then coming back and doing all the platform bits in one go afterwards is the most efficient method of working.

Stations' tendency to be done later is really down to how the design is progressed. Programme pressure means that the project cannot wait until all the OLE design is done and dusted before physical work starts. As you chaps have alluded to, open railway is generally less physically restricted than stations, which means the preferred and easiest to install OLE foundation solution can be used. Piles for OLE can generally be quickly sized by looking them up in "allocation" tables and diagrams provided in the Overhead Line Equipment Master Index (OLEMI) whereas other foundation solutions require bespoke structural design, which need more detailed surveys and more design time. This is why you generally see the piles along the stretches of open railway going in earliest in the piece.

Where the new OLE interfaces with existing OLE and other users of the track, there will be other programme (possession) constraints meaning the more difficult foundations have to be prioritised. This was the case with Barking.

The bridge lifting works will start early next year. This survey is to trace the water main that is to be temporarily diverted. There's quite a lot of enabling works to do before the actual jacking up of the deck. The two side arches are to be concrete filled to ensure the bridge load capacity is maintained post lift.

No, it will be a separate job. The bridge jacking will be done in a long weekend possession. The aim is to do much of the prep work behind hoardings to separate the work from the railway.

Looks like the next blockade is confirmed for 5 weeks commencing 17 September 2017. Network Rail have announced some public comms sessions over the next couple of weeks.

www.networkrailmediacentre.co.uk/news/public-invited-to-learn-more-about-gospel-oak-to-barking-line-closures

The second blockade's precise dates are yet to be confirmed but pencilled in for Nov to Jan.

No different to today - 4 tph daily. I suspect the PIXC extras in the peak including the Woodgrange Park to Willesden Junc working will cease because the new trains will be twice as long and more spacious inside (for more standees). TfL will no doubt be watching to see if suppressed demand suddenly surges forth making the EMUs very busy in the peaks.

The line will be extended to Barking Riverside in 2021. Again no planned service improvements on day one other than extra trains added to the fleet to run the longer service.

There are contract options to add a Boxing Day service (won't be happening this year) and also the possibility of an earlier morning start time and running the 4 pth service until close of service. Whether TfL has the cash to activate these enhancements is questionable and it's not known if Network Rail are keen to relinquish engineering hours for an earlier AM start. There may also be freight issues but that's guesswork on my part.

Beyond that there are three possibilities whirring round in the ether.

- lengthening the trains to 5 cars. Would need more platform works and possibly signalling changes (for sighting issues if stopping positions change). Probable depot changes to accommodate longer trains.
- increasing the service to 5 trains per hour. Obviously more trains needed for this and probably signalling changes to handle the higher frequency and depot changes for more sidings.
- a possible supplemental peak service which would involve a planned extra 2 tph from Enfield Town to Seven Sisters being run down the curve at South Tottenham and then on to Barking to add more peak time capacity between Blackhorse Road and Barking. This is an idea that has only recently reached the public domain but there is no time frame for this. It has long been known that TfL are very keen to add more peak capacity between Enfield Town and Seven Sisters where huge numbers change for the Vic Line. Any extra trains can't reach Liv St as there are no paths in the peaks.

The train supply contract with Bombardier has a number of pre-determined options in it to allow TfL to order more trains or carriages if it requires them. Once the 42 day objection period to the granting of the Transport and Works Act Order for the Barking Riverside line expires (hopefully without challenge) I would expect TfL to announce it is ordering more trains for the GOBLIN route to run the extended service.

Currently in the peak-hours, trains also use platform 7 and either reverse back from there or go into the siding to the east of the station and come back into platform 8.

Historically what were the average platform lengths on the line, and how different in terms of length would 5 car modern stock be to that? Once upon a time there was a suggestion that the WLL could move to 8 car trains; what would the 'hard' limit on length be for the Goblin, in distance and location?

Principally from air photos, my take on station lengths is:
Barking - this has the capacity for 12-car C2C units so it's unlikely to be a constraint.
Woodgrange Park - the old platforms look pretty much unobstructed so extending to circa 8-car platforms here looks simple. Beyond that and a couple of signals will need resiting. Extending northwest is not possible.
Wanstead Park - up to about 2 cars more on top of the present extensions is going to be relatively simple, another ~½ a car at the west end will be possible with minor signal adjustment. More than that and you are going to need to widen the bridges over one or both ends. Based solely on air photos, I'd say that extending the westbound platform east and the eastbound platform west is going to be the easiest. I'd be very surprised if the eastbound platform could be extended eastwards without demolition of one house.
Leytonstone High Road - the old platforms will get you about 3-4 additional cars westwards. Beyond that the eastbound platform could be extended another ~2-3 cars west without too much difficulty but it looks like a signal cabinet will need moving to do that. If you go this far, you really ought to look at a direct walkway alongside the Central line to Leystonstone. Extending the westbound platform westwards will likely require demolition of a single house, it might be possible to get away without it. More than that west on either platform and you need to widen the bridge over the Central line and A12 which will not come cheap. Extending eastwards is possible for about 3-4 cars on both platforms, but this will necessitate replacing the existing stairs to the platforms which are in the way.
Leyton Midland Road - both old platforms look to be unemcumbered enough to extend another ~4 cars eastwards with relatively little difficulty. More than that will require replacement of the bridge over Hainault Road, but after that there is another ~2-3 cars before anything looks to need relocating. Extending westwards is not possible.
Walthamstow Queen's Road - extending 1-2 northwest and 2-3 cars southeast looks like it will be relatively simple, depending on signalling positions. After that another ~2-3 cars northwest wont pose major problems, but will require more earthworks. That is the limit though without replacing road and/or rail overbridges.
Blackhorse Road - there should be little problem doubling the platform length by extending westwards here. A small amount of land take may be required from the college garden for the westbound platform, but that's about it unless there are small signalling cabinets in the way I've not spotted. Even 16 car platforms could probably be built here without too much complexity.
South Tottenham - extending eastwards there is space for about 1-2 cars more platform on the eastbound and 2-3 on the westbound before the junction. Another 1-1½ cars can be found for the eastbound platform at the west end I think, if you don't mind trains sat over the points while at the station but as eastbound trains don't need to use those points I think that would be acceptable. If you don't mind longer eastbound passenger trains only being able to use the Goblin route then you can extend along side the junction at the eastern end by as many cars as you want (although signalling changes will likely be needed). If you want more than that you will need to remodel the junctions at one or both ends, which will be expensive, although the land is there to do it - 12 car or longer platforms can be had here I reckon if you are willing to pay.
Harringay Green Lanes - 8 or maybe 12 car platforms could be possible here I think by extending north eastwards. If what look like piles on the air photo actually are, its possible that these platforms could just use those and so construction shouldn't be too expensive either.
Crouch Hill - it's difficult to see through the vegetation, but I don't think extending northeastwards here to 8 or 12 cars long will be either too difficult or too expensive.
Upper Holloway - the eastbound platform here can be extended with relative ease as far as you want, although trains coming from the "Up reception line" could only use about 1-2 cars more than the current extended platform. Westbound, there is about 3 cars without apparent difficulty (although a tiny bit of land take may be necessary), then another 1-1½ if there is space between the track and signal box. After that you will need to shorten the up reception line a bit to get more platform space.
Gospel Oak - assuming the train on the air photo is at the stopping mark, there is about 1 car of platform between there and the buffers, and maybe 1 car at the east end. More than 4 or, at a pinch, 5 cars here though will require track remodelling, a new bridge over the road and a small amount of land take from an adjacent business (although that doesn't look to be particularly high value land) - very expensive. An alternative would be to convert the current bay road into the westbound through road, the current westbound through into the eastbound through and the current eastbound through into a bay road with a platform on the north side with 12 cars easily provided for here, although at the expense of connecting it to the rest of the station and loss of cross-platform interchange. Depending where the railway boundary is it may require a narrow strip of Hampstead Heath. All in all this wouldn't be cheap either, but if I were I planner I'd want a ballpark BCR of both options before committing to either.

Gospel Oak wont take 6 cars in its current format I don't think, but 5 should be doable (just), and Wanstead Park might be tight with 6, but probably nothing SDO at a single door wouldn't cope with.
Beyond 6 though and your definitely talking serious money in several places.

I'm basing my estimates on Class 172 cars which are just under 24 metres according to Wikipedia, so 5 Mk 1 coaches are about the same as 4¼ Class 172 cars.

Others have covered the technical detail. Here is a little reminder of old times on the GOBLIN.

www.flickr.com/photos/28083135@N06/5818806001/in/faves-24759744@N02/ Photo Copyright - K Lane.

The contrast with today's view at Upper Holloway is stark to say the least.

Current TfL planning is that GOB will go to 5tph as soon as possible, but certainly after Riverside extension is open.  But only 4tph will operate through to Riverside.  The 5th train will use P1 at Barking.