Severn Tunnel safety

[PHILIPE]

LOL. Only want to cross the bridge not buy it.

You'd think you were buying the bridge with the cost of the tolls.

 

[PermitToTravel]

 

[Scott M]

So if you were on a train in the severn tunnel, would it look like it was raining? Except the 'rain' is the water flooding in.

 

[HSTfan!!!]

So if you were on a train in the severn tunnel, would it look like it was raining? Except the 'rain' is the water flooding in.

It's not quite that bad, you get a few drips on the windscreen and can see it running down the walls in places buts that's about it, it's not like driving through rain.

 

[Flamingo]

My one experience of walking in the tunnel it was quite dry, and going through it in the rear can of units I've never noticed anything wet.

 

[Hyphen]

So if you were on a train in the severn tunnel, would it look like it was raining? Except the 'rain' is the water flooding in.

As a passenger you can (for now at least!) test this out yourself by sticking your bonce out the 'offside' droplight (being careful not to collide with oncoming trains). You get a few drops of water on your specs but not much more.

The usual warnings about not doing that (and not admitting it) apply, of course

I don't know how much room there is between the 'nearside' window and the tunnel, and don't fancy trying it.

 

[Taunton]

I believe that Sodbury tunnel, on the other side of Bristol Parkway on this route, is immensely wet, always has been, and although I recall a big project (in fact more than one) on it to sort it out some years ago, there are still periodic diversions via Bath due to "flooding in Sodbury Tunnel". I do recall that one drainage proposal for it was rejected by the area water authority who refused to put the drainage into any of the local watercourses and said that the railway should drain Sodbury right through into the Severn estuary, must be about 10-15 miles. Not sure if that was done.

 

[Llama]

Most tunnels need the wipers on, I sign umpteen miles of Pennine tunnels and the majority are wet, and some have flood alarms, despite not being under bodies of water.

The comment about diesel fumes corroding the rails is well wide of the mark too, if that was an issue then in Morley and Standedge tunnels we would be running on the sleepers by now. If anything diesel fumes could possibly lengthen the life of the rails, as negligible as their effect would be either way, as traces of unburnt diesel oil tend to end up coating every surface. The issue is likely to be the saltwater which really doesn't like rails, and perhaps reacts with other compounds in the diesel deposits.

 

[DY444]

Maybe these changes you describe to the signalling block sections were made in the aftermath of the 1991 Severn tunnel accident

Nope. It was a single section before that collision

 

[Taunton]

As I understand the signal section, it is about 5 miles long, and was back at the time of the accident, which simplistically was the result of one train being handsignalled in following a signal failure and so going through very cautiously, whereupon the handsignalman was withdrawn and the following train somehow got a green signal (S&T were working on the axle counters at the time) and thus went through at normal speed, and in the darkness and low visibility caught up with the one ahead. However, there is an emergency signal halfway through which can be set to red either by the signalman or by breaking the "tell tale" wires which have always been run through the tunnel, back to GWR days. There is no track circuiting, apparently due to unreliability, although the accident report seemed to show the axle counters suffered considerable unreliability of their own.

Regarding the life of the rails, as I described earlier it was like this back in steam locomotive days, they were replaced after about 6 years, so not diesel fumes. They were then apparently used elsewhere so were not unserviceable. Someone from the PW side can maybe explain the actual reason for this. Certainly in steam days the tunnel was closed on winter Sundays as there was so much work done inside, the passenger diversion was via the Severn Bridge until that was destroyed in the ship collision in 1960, when a further diversion through Gloucester was needed.

 

[kjhskj75]

Coal often contains sulphur, so the smoke would react with the water to make suphuric acid, which would not be kind to the rails.

 

[Clip]

Not only that ^^ but surely with drips coming down in the same place day after day then they would start to get pitted in these areas surely?

 

[jon0844]

it was probably going to be slower than the tunnel, by the time the train driver stopped at the toll booth, got out his money, got his change and receipt, waited for the barrier to raise and pulled off again there was no speed advantage...

At least it's only in one direction! The question is how the driver gets all the passengers to chip in. Or is that your job to sort?

 

[Flamingo]

At least it's only in one direction! The question is how the driver gets all the passengers to chip in. Or is that your job to sort?

Easily done - just pass the hat around with a cry of "How much is it worth to get out of England!"

I'd probably run at a profit!