District and Hammersmith & City line part closures

[sawb]

Does anyone know why the District and Hammersmith & City lines always (seemingly) have to close through the affected section when there is engineering work on the adjoining c2c tracks, but when the underground tracks are closed, c2c can get away with just a 40mph speed restriction, or does it just depend on what work is being done?

[Colin]

We don't automatically suspend for c2c works. They often have Monday to Thursday evening closures between Fenchurch St & Barking or Barking & Upminster and we happily carry on running, no bother at all

A couple of area's where you might see us (LU) suspending would be if they had work specifically in platform 7 at Barking or platform 8 at West Ham (both adjacent to our westbound track).

Sometimes you'll get joined up working though, like this coming weekend. We're both suspended Upminster to Barking - LU is having Hornchurch crossover taken out and plain lined whilst c2c (actually Network Rail are also replacing some of their track.

[superteacher]

It's been discussed elsewhere, but I don't see the logic of removing crossovers such as that at Hornchurch.

[Colin]

That makes two of us!

[North End]

Jan 10, 2016 11:32:41 GMT superteacher said:

It's been discussed elsewhere, but I don't see the logic of removing crossovers such as that at Hornchurch.

Cost.

To be fair Hornchurch is very rarely useful, it's too near Upminster to be any use for engineering work, and likewise not much use for late-running - and in any case some trains will have a crew relief at Upminster so reversing short wouldn't be an option. So the main value is if there's a problem at Upminster - it's a balance between the cost of maintaining it versus the value it provides. Evidently it wasn't felt worthwhile.

I'm less convinced about the removal of Bromley, that seemed to get used from time to time.

[Deleted]

Jan 10, 2016 11:32:41 GMT superteacher said:

It's been discussed elsewhere, but I don't see the logic of removing crossovers such as that at Hornchurch.

I'm very preservationist in this regard, too, and I think it's a shame to lose emergency crossovers and, arguably, quite short sighted.

However, another point is that trailing crossovers, such as at Hornchurch, make less sense with high frequency train services. This is because, if you want to reverse east to west at Hornchurch (to take the example), you have to change ends in the platform (which takes time, especially if platforms are busy), wait for a gap on the westbound and head over the crossover. All the while this is being carried out, the eastbound is blocked by the reversing train and other trains are likely to be held up. Even with TBTC, depending on the location of the crossover, it may - additionally - not be possible to bring a train into the westbound platform, which can hold up the westbound as well. On top of this, you now have the issue of a trainload of passengers being dumped on the eastbound platform, and passenger confusion, with people wanting to go east ending up heading off in the wrong direction. Now, obviously, the clogged up platform is gonna further delay following eastbound trains, as it will increase dwell times, which will likely ripple back if you're running very high frequencies.

In fairness, all of this is less true at Hornchurch, but if you think of places like South Ken and Bromley-by-Bow, the scheduled services are very frequent and it's often better to let a late running train carry on (say to Barking, in the case of Bromley-by-Bow), than to try to recover time using an emergency crossover, because you just end up delaying following trains instead/as well.

So with resignalling set to increase frequencies, it's not unreasonable to predict that crossovers like these will become even less useful, primarily being relegated to planned engineering works. But you simply can't run a respectable number of trains if all trains are terminating somewhere like Hornchurch, because you've just got the one platform. Which is why scissors crossovers are being brought in in places like KCSP and Westminster, because then you've got two platforms to play with.