Dartford Loop / Bexleyheath Line

[Daz28]

I have noticed that whenever there is disruption on the Dartford Loop line (via Sidcup) or the Bexleyheath line, the standard response is to close the line. If during peaks, trains will be diverted down one of the other two lines to Dartford, sometimes stopping, sometimes running fast. At least when they stop, there is the bonus of additional trains at the unaffected lines, and we are fortunate to have good bus links that cross the three lines, so it is possible to get to roughly where you want.

My question is are there any technical reasons why services cannot still run on the affected line? For example, today there are no trains on the Bexleyheath line, whilst they repair the landslip at Barnehurst. There is a replacement bus from Lewisham to Dartford. Why can't they run Charing Cross to Bexleyheath and reverse there?

There are regular services in the peak that reverse at Sidcup (there is a siding there), but when there was disruption at Crayford recently, there was no service on the whole line.

If there are problems closer to London, it should be possible to run trains the long way round, but they never do.

Is there a signalling reason, or an electrical isolation limitation that prevents such flexibility, or is it just more convenient to close the line when things go wrong?

 

[yorkie]

Why can't they run Charing Cross to Bexleyheath and reverse there?

No reversal facilities there.

There is a crossover east of Barnehurst but if the works are at Barnehurst that won't help

 

[MidnightFlyer]

Where's the next one westward? Single line working might be an option but it's not brilliant if you want an intensive service.

 

[yorkie]

Kidbrooke - which only serves one station that isn't served by alternative routes!

 

[OxtedL]

There are regular services in the peak that reverse at Sidcup (there is a siding there), but when there was disruption at Crayford recently, there was no service on the whole line.

If there are problems closer to London, it should be possible to run trains the long way round, but they never do.

Is there a signalling reason, or an electrical isolation limitation that prevents such flexibility, or is it just more convenient to close the line when things go wrong?

As Yorkie mentions, the Dartford lines generally lack reversing facilities. You can see where there are crossovers on this map. There is nothing on the Bexleyheath line between Kidbrooke and Barnehurst, while on the Loop line the only reversal point west of Crayford is the one you note at Sidcup.

I think more or less answers all your points, but it's also worth bearing in mind that Southeastern routes are heavily interlinked and very complicated, so in short term disruption simply diverting services is actually quite sensible as it keeps trains moving to where they need to be ready for when normal service resumes.

Turning trains round at short notice and doing other exciting things can get them in the wrong place and if not done carefully might make it extremely difficult to eventually return to normal service - we've all seen days when something has gone wrong and delays still linger hours after it's fixed. When disruption might only last for a short time it perhaps isn't worth doing, in the overall balance of things.

 

[ChiefPlanner]

Most services loop round (e.g out via Greenwich , back via say Sidcup) - SLW , if it were possible (previous comments -would spread disruption far and wide - bearing in mind the standard turnround at Charing Cross is 7 mins)

Besides - the bankslip brought down a lot of trees and chalk / slurry - and the engineers need(ed) a safe space to work , and to clear away. Not forgetting the 3d rail isolation needed.

 

[Bald Rick]

I think more or less answers all your points, but it's also worth bearing in mind that Southeastern routes are heavily interlinked and very complicated, so in short term disruption simply diverting services is actually quite sensible as it keeps trains moving to where they need to be ready for when normal service resumes.

Turning trains round at short notice and doing other exciting things can get them in the wrong place and if not done carefully might make it extremely difficult to eventually return to normal service - we've all seen days when something has gone wrong and delays still linger hours after it's fixed. When disruption might only last for a short time it perhaps isn't worth doing, in the overall balance of things.

Exactly this reason. It is much easier to keep a track of crews etc, and this limits the spread of disruption and enables a much quicker restoration of normal service.

Also the fact that the lines are so close and have half decent bus links between them means that passengers are not as badly inconvenienced as is the case elsewhere. I have a number of friends who live between two of the lines, and if there is a problem on one they take the other.

 

[dysonsphere]

Thats a very nice map but it looks rather like the Quail map for London wonder if its been copied.

 

[Mintona]

I believe the crossover at Kidbrooke has now been removed as well, so that's no good either.

 

[Carlisle]

I believe the crossover at Kidbrooke has now been removed as well, so that's no good either.

Does not sound like a good idea from network rail or whoever to decrease operating flexibility like that when the future if anything will surely be more trains not less on those routes

 

[Bald Rick]

Does not sound like a good idea from network rail or whoever to decrease operating flexibility like that when the future if anything will surely be more trains not less on those routes

When there are more trains, the last thing you want is them blocking a running line waiting to turn back.

 

[Carlisle]

When there are more trains, the last thing you want is them blocking a running line waiting to turn back.

Ok cheers for clarifying the thinking these days ,I was aware quite a few crossovers had been removed from the uk network in recent years but was unsure why

 

[Tomnick]

Perhaps not the case here, but the gradual removal of crossovers on longer routes, carrying longer-distance passenger and freight traffic does make it much more difficult to either work around an obstruction or at least keep the 'bustituted' section as short as possible. The usual frequency of trains doesn't matter as the majority, if it's a really frequent service as in this example, will be diverted, cancelled or turned back elsewhere anyway. The relative infrequently of use of such crossovers, though, presumably doesn't justify the cost of retaining them all.