Beckton Park to Cyprus

[Chris M]

Why does the track between Beckton Park and Cyprus return to surface level only to descend back below the road again?
Surely this uses more energy in accelerating and more wear and tear on the brakes, etc?

[Deleted]

Hmm, an interesting one. I'm sure the answer might be in the DLR Official Handbook, published by Capital Transport.

[Deleted]

Probably to avoid having to dig a cutting for it.

[Deleted]

It's sort of on a hump. Maybe its to do with the water table, as the Royal Albert Dock is very close. Maybe there are outfall pipes below at that very location.

[suncloud]

Probably to do with cost in that building road and rail at ground level is cheaper than having one above or below the other, but at the road junctions/stations they have to be. Just as the rail dips down to the stations the road goes up to the roundabouts. I don't think it's anything more complicated than that. I doubt the effect of gradient on energy/wear & tear is very significant, at least not in comparison to some of the other gradients on the network.

[Chris M]

Pipes could be the reason I suppose. They had to dig a cutting for the stations at either end, and then the ramps out from each of them, so I don't think having the cutting the entire length would have been significantly more expensive or difficult than what they did. Particularly when you take into account long-term costs.

I've not been able to find a gradient profile for the DLR online, other than the maximum gradient down to the Bank tunnel is 6% and the maximum on the Island Gardens-Cutty Sark tunnel is the same figure.

[Deleted]

there is a roundabout ontop of both beckton park and cyprus stations so i am guessing that the road was there first??

[Chris M]

I've always assumed that the road and railway were built at the same time, or at least if the road was built earlier it was built with provision for the DLR to come later. The Cyprus "roundabout" isn't actually a roundabout as there is no junction. There is the stub where a road to the south would connect, but building one now would require the demolition of at least one university building and the destruction of the campus' main square.

[Deleted]

Mar 18, 2011 20:00:48 GMT Chris M said:

I've always assumed that the road and railway were built at the same time, or at least if the road was built earlier it was built with provision for the DLR to come later.

Spoke with a neighbour who was here at the time this was built, he recalled that the building of the DLR and the main road was all done as one project - he recalls that the rails were put down before the road was opened, although it took a long time after that before the DLR service started.

Regarding the up and down of the line between the stations, our civil engineering expert in the office here, who commutes that way on the road, said he would have done the same - he guesses the two stations under the roundabouts are below the ground water level and will need special drainage or pumping anyway, so you don't want a long level piece where water builds up and is difficult to keep watertight and drain, but just two points, one at each station, where it slopes down to. He said the Channel Tunnel is done the same way, being a very prolonged W shape with the two bottom points near the coast so it is easy to get the water out, rather than having to pump any leakage from the middle of the Channel.

Or at least, that's how I remember it being described. Does it make sense?

[Chris M]

That does make sense. I hadn't thought about water issues at all.