Heavy rain in Devon - flooding on the railways

[Gwiwer]

It would also require a total rebuild of the railway in order to achieve this. Either on an all-new alignment (where does that go at Cowley Bridge?) or involving lengthy closures while the old is converted. I don't know the detailed geology of the Exe Valley despite having trained as a geologist but I suspect the "soft muck" will go down at least 10 metres from surface making each and every pile or support hugely expensive as has been said. Whether slab track would be any better in the medium-term perhaps someone such as the good Captain might be able to comment upon. There would be no more traditional ballast to wash out but what then if the footings were undermined?

 

The Exe carries huge volumes of water when in flood and does so through a relatively narrow valley as it approaches Exeter. Any volume of liquid expected to flow through a narrowing gap will tend to accelerate as it does so. To test that hypothesis pour water into a funnel and compare the apparent rates of flow at the wide brim and the narrow outlet. The faster the water moves the greater is the "carrying power" of the river meaning it can pick up and transport larger and larger items. Such as ballast. In its normal state the Exe carries fine mud in suspension but in flood as we have seen carries not only ballast but larger objects as well. Gravity sees to it that these items cannot be shifted under more normal conditions otherwise the ballast would wash away every time it rained!

 

Channeling the Exe into a narrower path is therefore not a solution and the realistic way ahead is to raise the entire railway farther above the flood plain at huge cost but probably on embankments with wide culverts rather than on an extended raft. The river, after all, was there first and has had its natural environment interrupted and altered by the railway.

[10800]

Infrastructure nowadays is generally designed (in flooding terms) to cope with certain flood events, usually defined by a duration (6 or 24 hours for example) and a 'return period' (50, 100, 200 years or whatever). Victorian infrastructure may not have been built consciously to those standards but often is because, well, that's what the Victorians did. Bear in mind that a so-called 100-year event doesn't just mean it is likely to happen once every 100 years, it means there is a 1% chance of it happening any (or every) year. Traditionally it isn't considered justifiable to design and build structures for events more extreme than the defined standards because of the cost and likelihood of it actually being needed. Risk assessment is the name of the game. Nobody is going to spend billions on something that has a low hazard rating (in terms of human life anyway) and is very unlikely to happen. You just deal with the consequences if it does.

 

A factor now though with climate change/weird weather is that the basis of the weather statistics used for defining extreme events is moving all the time. This may or may not entirely be due to the climate change itself, although one of the features of climate change that most people agree on is that the system will become more volatile and odd or extreme rain and flood events will become more frequent even if average rainfall decreases.

 

But getting back to the floods of the last couple of weeks, they will also have been exacerbated by the ground still being saturated from all the rain over the last few months so that 'buffer' that is usually available to ameliorate the volumes of runoff is not there.

 

So engineers, designers and planners are going to have increasingly tough times in defining what exactly is needed in practical terms in the future, and how much can be justified in spending on it.

[The Stationmaster]

 

That sounds the sort of thing that would be needed. It all depends on how frequent the floods become. Probably too expensive but how often do we realise the seemly more expensive option would have been cheaper than keep repairing things.

Don

Very true Don and let's not forget that a lot of work has been done in the past to mitigate the effects of the usual seasonal flooding at Cowley Bridge Jcn and generally that work has paid off. Nowadays bad flooding there only seems to happen when we get exceptional weather and - as Rod has noted - the latest spell of heavy rain fell on saturated ground making its impact far worse than normal.

[Glorious NSE]

I would count myself as rather pro-rail, but I can think of better places to spend multiple billions than preventing a weeks closure during freak weather every decade or so.

[southern42]

All this is interesting but it's set the imagination off a bit....

 

When we popped in at Shildon (NRM) after playing trains on Porth Eithin at the Hartlepool exhibition, we saw some action going on along the tracks.

On asking, we were told they were trainees learning how to prevent the ballast turning to concrete - preservation line helping out the mainline. Nice one.

 

The job you're faced with in Devon is a bit more serious than that but it is nice to have some understanding of trackbed construction. It's a long time since we 'did' Roman road building in junior skool, but I guess the pricnciple principle is pretty much the same.

 

Something to think about when we're modelling?

After this season's floods, I wonder if water will be appearing on layouts, now, flowing down embankments, bridges, retaining walls or floods 'up the line' used as an excuse for all those derailments, late arrivals and breakdowns?

 

"Sorry mister, our FGW express passenger train is held up due to last night's floods..."

 

And will there be an increase in Permanent Way flood repair activity before you reach the fiddle yard?

I'll be looking out for them at next year's exhibitions. I'll be counting!

 

[Captain Kernow]

To put things in context, here are some photos of the last serious wash-out at Cowley Bridge Jct - in December 2000:

 

 

 

 

 

[devondynosoar118]

The middle picture is almost identical to this years one. Hope things have been a bit calmer this week. Don't worry, it'll snow soon....

[Captain Kernow]

Hope things have been a bit calmer this week.

 

Negative, Caller!

 

Don't worry, it'll snow soon....

Why, thank you for that positive and motivating thought!!

[devondynosoar118]

Oh dear, sounds like the overtime is racking up already! Let's hope nothing biblical happens to the weather until at least after Christmas for the sake of Tim and his crews.

[petethemole]

" I don't know the detailed geology of the Exe Valley despite having trained as a geologist..."

 

For local geology anywhere in UK try this:

 

http://www.bgs.ac.uk/discoveringGeology/geologyOfBritain/viewer.html?src=topNav

 

Go to "Open Geology of Britain viewer and enter the location. A very useful tool in my job; it saves buying the paper maps.

Pete

[Captain Kernow]

Oh dear, sounds like the overtime is racking up already! Let's hope nothing biblical happens to the weather until at least after Christmas for the sake of Tim and his crews.

Overtime?! What overtime?! Some of us don't get paid that!! (although there are plenty of colleagues working very hard and very long hours to get everything fixed).

 

With the signalling at Cowley Bridge Jct not yet restored, it is the intensity and time-consuming nature of detailed planning of movements and shunts that would normally be simple, but now, with altered methods of working, become complex.

[The Stationmaster]

 

Look at it this way Tim: it dusts off the skills of the staff for basic operations, instead of relying (too heavily) on technology And as a bonus: over time you gain the experience to make it easier

 

While it might dust off some skills I don't necessarily think that 'gaining the experience' makes it any easier - complex operational tasks are always complex operational tasks are always complex tasks and different things have to be tackled in different ways using your knowledge and skills in different ways. Even doing the same thing over and over doesn't mean it will be exactly the same every time in such circumstances, especially as trains can run late or adrift of booked path in umpteen different combinations thus presenting slightly different problems which might require different answers.

 

The experience doesn't necessarily make it easier to deal with but it can - and usually does - give you a wider range of know;edge about how things might have to be dealt with - but you have to know how to do it in the first place.

 

As for overtime payments an increasng number of jobs and grades on the railway have said good bye to such things, especially since privytisation. But as a front line manager in operations I happened to say good-bye to overtime on a particular promotion back in 1974 and plenty of us were prepared to work very long hours in order to keep the job going without even thinking about the fact that we weren't getting anything extra in cash terms for doing so. Bit of an old-fashioned attitude I know and the main reason for going to work is money - but it's not the only one and some of that sense still prevails in parts of the railway industry, fortunately.

[Captain Kernow]

I don't necessarily think that 'gaining the experience' makes it any easier - complex operational tasks are always complex operational tasks are always complex tasks and different things have to be tackled in different ways using your knowledge and skills in different ways. Even doing the same thing over and over doesn't mean it will be exactly the same every time in such circumstances, especially as trains can run late or adrift of booked path in umpteen different combinations thus presenting slightly different problems which might require different answers.

 

 

Bit of an old-fashioned attitude I know and the main reason for going to work is money - but it's not the only one and some of that sense still prevails in parts of the railway industry, fortunately.

 

All very well-said, Mike, very well said indeed.

 

The thing is, Vincent, (and I know you meant well when you wrote it), we have no choice but to rely on the technology on a day-to-day basis. That's how our railway is designed (and your's too!). Whether we like it or not, we rely on the electronics, the machinery, the interlocking - whatever it is that makes the railway a safer operation now as compared with yesteryear. Who can argue that a fully functioning, properly designed and built NX panel is less safe than a Victorian lever box on a busy main line with no track circuits and generally fewer safeguards?

[APOLLO]

Little bit of water - SEND EM THRU - Steam Diesel or Electric - NO PROBLEM !!!!!!!!!!!!!

 

 

[Gwiwer]

"Send 'em thru" might seem reasonable and there is entertainment and curiosity value in those images. Steam could sometimes get through floods provided the water didn't reach up to the boiler. Cold flood water and a hot boiler are not a good mix. Modern traction can only proceed until the point at which electric traction motors (often axle-hung) become engulfed or, if not electrically powered, until water reaches critical parts of the diesel engine.

 

What cannot be determined is how stable the track is beneath the water. There are many pictures of steam locos "wading" through floods to almost platform height. In such situations slow-moving water probably hasn't done too much damage to the formation. But once that water flows as opposed to pooling in a dip it scours the track bed causing washouts. In today's Elfin Safety-managed society (which exists with a lot of good reason) the risk is to great and the job stops.

 

I can offer a comparison with parts of Australia where there is occasional severe flooding. I worked for some years on the city's trams (the largest network in the western World and arguably anywhere) which suffer the same problem. Water over the rails was seldom an issue but once it reached a few inches everything stopped. Our suburban railways also have flooding "hot spots" where water either ponds or uses the railway as an emergency water-course. Again the job often stops entirely although on one occasion we were let through at walking pace with torrents of water flowing over the tracks but only an inch or so above rail height. Nevertheless there were many audible impacts with debris and a few shudders as we struck water-borne tree branches and washed out ballast. While grateful for getting home that's not an experience I would choose to repeat.

[Ozexpatriate]

Little bit of water - SEND EM THRU - Steam Diesel or Electric - NO PROBLEM !!!!!!!!!!!!!

The enormous crowd gathered on the overbridge to watch that tank locomotive plow through the cutting suggest this was not a regular occurence. Guessing by the amount of steam and the wake, this driver was flogging that engine and was probably either terrified or foolhardy.

 

"Send 'em thru" might seem reasonable and there is entertainment and curiosity value in those images. Steam could sometimes get through floods provided the water didn't reach up to the boiler. Cold flood water and a hot boiler are not a good mix.

I would think that water up to the grate or the firebox would be pretty catastrophic too.

[Donw]

Memories of winters long ago have been related to me where the railways were the only means of getting supplies through. On the island there has been flooding along the eastern yar and the only thing getting through were the steam trains. In Shropshire the Wenlock edge was closed for weeks due to heavy snow. At Easthope the farmer got over the hill on horseback to Easthope station to get bread and others supplies for the village. A different world to today.

Don

[Gwiwer]

A different world to today.

 

Different even to a few years ago.

 

It's not that long ago that I was driving buses and coaches around the western extremities of the Good Captain's Land. Often the first landfall of storms we had more than our share of floods, trees down and sometimes icy roads. It seldom snowed but topsoil washed off fields by heavy rains formed dams where it ran out onto the roads and caused water to pool sometimes to substantial depths.

 

Even in the most arduous of conditions we considered that the public were paying for a service and that we had to get through no matter what. My colleagues who went up-country on National Express duties carried empty sacks (for traction) and shovels in the event they met snow. We coped with winds sometimes gusting near 100mph, waves thrust up above cliff tops often carrying seaweed and shingle in the water, we got through floods and even offered shuttles from one side of a flood to another for villagers in need of getting to and from a shop (and for which no fare was charged). If the official route was icy and we didn't like the look of the hills we found another way round. It was all part of the service and we neither sought nor, very often, received thanks for it.

 

That's all changed now. A few spots of water on the roads and buses scurry for the cover of their depot never to be seen again in the interests of safety and woe betide the driver who might be happy to continue their shift and get people where they need to be against the "advice" of management.

[caradoc]

That's all changed now. A few spots of water on the roads and buses scurry for the cover of their depot never to be seen again in the interests of safety and woe betide the driver who might be happy to continue their shift and get people where they need to be against the "advice" of management.

 

All transport operators have a duty to consider the safety of both passengers and staff in adverse conditions. There is currently a court case in Scotland concerning the coach taking schoolchildren to Alton Towers (not exactly an essential journey) which crashed in icy conditions causing the death of a young girl. Would it have been better if that coach had stayed at the depot and the trip cancelled ? With the benefit of hindsight, yes.

[Gwiwer]

I entirely accept that logic. From my point of view however if I were already working a rostered shift with passengers aboard a vehicle and waiting along a line of route my duty was to get them (safely) to where they were going since to abandon them to wild weather was probably the grater risk.

[jamie92208]

Having read most of the previous page of comments there are quite a few suggestions as to whether or not a railway can be built that is designed to flood. The answer is yes. there was an article in 'Trains' magazine a few months ago about a coal carrying branch line in the eastern USA that did just that.It was along a river valley and crossed the stream a few times and suffered from frequent washouts. It solved the problem by building culverts at the crossings and then making a concrete trackbed above the culverts with the rails set in the concrete. They have had problems with scout=r and have had to learn how to design the abutments on the job but they have kept the line going. I will try and find the reference, it's a fascinating read. However the message that i remember is that it isn't easy.

 

 

Jamie

[ess1uk]

Having read most of the previous page of comments there are quite a few suggestions as to whether or not a railway can be built that is designed to flood. The answer is yes. there was an article in 'Trains' magazine a few months ago about a coal carrying branch line in the eastern USA that did just that.It was along a river valley and crossed the stream a few times and suffered from frequent washouts. It solved the problem by building culverts at the crossings and then making a concrete trackbed above the culverts with the rails set in the concrete. They have had problems with scout=r and have had to learn how to design the abutments on the job but they have kept the line going. I will try and find the reference, it's a fascinating read. However the message that i remember is that it isn't easy.

 

Jamie

Were there's a will, there's a way.

It wasn't easy to build the railways in the first place with only man power, but they were built.

[R A Watson]

 

Were there's a will, there's a way.

It wasn't easy to build the railways in the first place with only man power, but they were built.

 

Yes, but , remember that the infrastructure whose damage we are discussing here was built in the early 1850's and has in the main been untouched till now. The same goes for the other areas which have featured in complementary threads recently.

 

The dating of the two sets of pictures which Tim has put on this thread requires attention, the two breaches are several hundred yards apart as the crow flies and twelve years apart on the timeline.

 

Perhaps the design requirement of "hundred year" events is not too far out.

 

Wally

[Captain Kernow]

Iif I were already working a rostered shift with passengers aboard a vehicle and waiting along a line of route my duty was to get them (safely) to where they were going since to abandon them to wild weather was probably the grater risk.

 

Do you know, Rick, I just cannot agree more vehemently with that sentiment if I tried. Of course we have to get the passengers to safety! There was a spate in the early years of privatisation of leaving passengers on a cold, unsheltered and unstaffed station, simply because the door interlock system on a sprinter got into trouble. It was complete and utter bo**ocks, of course, and went against the grain for every time-served railwayman. Fortunately, the TOCs these days tend to deposit their customers at stations that are suitable to deal with stranded passengers under similar circumstances, however temporary their stay there is expected to be.

[APOLLO]

"Send em thru" was tongue in cheek - couldn't resist, especially the video !!.

 

I have nothing but praise for those of all grades at the "sharp end" who have to work long hours and dammed hard usually in hostile environments to get things going again in situations like this. I've been there myself on countless occasions, though in the Gas industry. We were indoctrinated (in the good old "North Western Gas Board" days) that the customer was king, and gave service accordingly. Didn't allways go to plan (sometimes we had no plan !!), but, that's life.

 

Well done indeed to those of you who were involved.

 

Brit15