Snow, and what happens if it comes?

[philthetube]

Where third/fourth rails are concerned the worst weather is when it snows, washes off the de-icing fluid, settles on tracks and the freezes. Can only be removed by scraping or melting.

 

[Jim Jehosofat]

I can remember walking in front of 8EPB with a shoepaddle removing nthe snow from the third rail between Barnehurst and Bexleyheath in the winter of 86/87. No Hi-vis, just a BR management overcoat over the BR issue suit. Can also remember a driver volunteering to driver a train from Charing Cross to Ramsgate and back, out via Tonbridge, Ashford and Dover and back via Faversham and Dartford via the North Kent line. All sorts of loco hauled EMUs out of Charing Cross, one famously via the middle road which was banned to locos!

 

[ChiefPlanner]

I can remember walking in front of 8EPB with a shoepaddle removing nthe snow from the third rail between Barnehurst and Bexleyheath in the winter of 86/87. No Hi-vis, just a BR management overcoat over the BR issue suit. Can also remember a driver volunteering to driver a train from Charing Cross to Ramsgate and back, out via Tonbridge, Ashford and Dover and back via Faversham and Dartford via the North Kent line. All sorts of loco hauled EMUs out of Charing Cross, one famously via the middle road which was banned to locos!

All hands to the pumps in BR days - we cleared the blocked points at Motspur Park with 2 domestic brooms and some dustpans ....(see previous messages) - the BR shoe paddles were far superior to the LT ones as they were much firmer / solider - so you could belt the con rail to loosen it , then scrape off. Akin to a cricket bat.

We acquired some garden water / mist spray pumps - which were excellent for pro-active local point clearing - money taken out of the booking office and a taxi to B+Q to buy their entire stock . Great also for spraying door wells on sliding door stock (455) , something I used much more widespreadedly on North London Lines when we used to treat the 313 / 321 outberthed stock overnight , (+ heaters left on full) , with copious amounts of equipment at key stations. Any driver who so wanted , could take a fully charged de-icing pump in the cab. By this time - 199x onwards though - we did have some concern for PPE (goggles available) -

 

[bramling]

However it isnt just snow that causes the problems, especially in the south. Frost on the con rail is just as bad - that needs to be mitigated

We have de-icing fluid on conductor rails and point heating to take care of that, which providing both measures are fully operational should be effective at most normal conditions. As such it’s rare for a train to get stuck just due to frost- except perhaps if starting up after a possession or whatever.

Snow is a different ball game entirely, simply because of the scale. It throws much more of the problem, often in a much more concentrated period of time, and throws up all manner of other operational issues which all added together means operating staff are heavily stretched.

 

[HSTFan57]

I've seen a few winters with substantial snow and ice in Bristol in the last 10 years, and the trains seem largely unaffected, even when road transport was severely impacted. The various HSTs, Pacers, 150s and 158 don't really seem to notice snow and ice, apart from the HSTs which sometimes seemed to accelerate more slowly than normal. It might be relevant that all the stock is currently diesel, maybe 3rd rail and OHLE is more vulnerable to snow and ice.

 

[Chris M]

Top-contact third rail is I believe the most vulnerable to snow and ice as it settles on the contact surface and freezes, which acts as an electrical insulator.
Bottom-contact third rail (as used on the DLR) is significantly better, as gravity keeps the contact surface clear. That is until the volume of snow, or drifts, reach the contact surface height (I think it's about 75cm on the DLR, but I can't immediately verify this), but this takes longer, giving more time to clear it.
OHLE is vulnerable, but not to the same extent, as the cross-sectional area is much smaller and contact is made with the bottom surface. I think the main problems come from weight of snow and from high winds - electrical problems are more likely to be on the train than the OHLE. Freezing rain is a problem, but I don't think that is especially common in the UK.

 

[DarloRich]

Top-contact third rail is I believe the most vulnerable to snow and ice as it settles on the contact surface and freezes, which acts as an electrical insulator.
Bottom-contact third rail (as used on the DLR) is significantly better, as gravity keeps the contact surface clear. That is until the volume of snow, or drifts, reach the contact surface height (I think it's about 75cm on the DLR, but I can't immediately verify this), but this takes longer, giving more time to clear it.
OHLE is vulnerable, but not to the same extent, as the cross-sectional area is much smaller and contact is made with the bottom surface. I think the main problems come from weight of snow and from high winds - electrical problems are more likely to be on the train than the OHLE. Freezing rain is a problem, but I don't think that is especially common in the UK.

You do have to run trains overnight to keep the contact wire free from ice.

 

[gsnedders]

OHLE is vulnerable, but not to the same extent, as the cross-sectional area is much smaller and contact is made with the bottom surface. I think the main problems come from weight of snow and from high winds - electrical problems are more likely to be on the train than the OHLE. Freezing rain is a problem, but I don't think that is especially common in the UK.

My memories of when I lived in Sweden was the big problem there with OHLE was when there was freezing fog; some trains, like the X2 had no problem with the rime on the OHLE, but others like their partial replacement X55s couldn't go anywhere. The X2's were, admittedly, rather expensive and over-specified and built specifically for the Swedish market.

 

[notverydeep]

Significant snow is infrequent in lowland England and Wales more or less all the way up to the Southern Uplands, whereas it is fairly common on the uplands down as far as the Peak District and the Brecon Beacons. Lowland snow is often characterised by a light fall that persists for a short time. When it is, the equipment and procedures used for icy weather in general, will work fairly well for snow – gritting surfaces, de-icing, point heaters etc.

These procedures have been refined and some weaknesses dealt with, although often after painful lessons such as the need to shield air intakes from snow ingress, such as the infamous ‘wrong kind of snow’ and the more recent Eurostar snow ingress issue. Weather forecasts are much more accurate and helpful to the industry than twenty years ago and (as others have noted) they are used throughout the industry to aid planning and preparation. There will still be problems, but they won’t generally amount to network paralysis.

It is more substantial snow falls that are the more troublesome. At the altitude of most railway lines, nowhere in the UK are such heavy falls a frequent occurrence. Sure, as you go north the risk does increase, hence the concentration of the specific resources further north, where they are more likely to be put to good use there. However, even around Inverness, the snow-ploughs can easily go a whole winter with just training runs.

In order to cope with heavy falls comprehensively, expensive equipment must be purchased and additional procedures added. These would require costly maintenance and continuous training to maintain competence but with little actual application. As any train driver will tell you, keeping skilled with many different fault finding routines that you may only require once in five years is a demanding requirement. When finally called upon, such processes won't benefit from any learning curve of repeated experience and staff will inevitably take more time to do the task than they would if familiar. As others have noted, even countries with regular heavy snow find that the first such events of the year are quite disruptive as everyone relearns how to cope. The number of trains per year delayed by snow in Norway and Sweden is certainly not zero! Being well prepared for heavy snow would therefore have a significant ongoing cost which is unlikely to be justified by occasional application. In short, it is rational to just have a day with little or no service once every five years. This fact is rarely stated as it isn’t an easy sell...

Then there are the emergency services. Over the last few decades, it has become apparent to them, that road accidents, deaths and injuries spike during heavy snow episodes, the additional hazards and unfamiliar population make that inevitable. This of course drives up their workload at a time when they (like everyone else) find working more difficult. They are incentivised to minimise accidents such and injuries, while they are not accountable for the loss of productivity or disruption to the economy. This means that they have a strong incentive to ‘advise against travel’, even when holistic consideration of other considerations might suggest a higher threshold.

This advice then sets off a chain reaction. School children may mostly have short walkable journeys, but a teacher coming 10 miles can legitimately take account of such advice. Faced with a likelihood of either too few staff members and possible last minute closure, schools are then incentivised to make a decision on closing quite early to avoid unnecessary journeys where other members of staff and parents discover that a school is closed on arrival. At this stage all sorts of people (including railway staff) face both advice not to travel and in many cases a need to provide unplanned child care and thus the working day grinds rapidly to a halt.

Railway companies have also discovered that making a huge effort to operate immediately after heavy snow fall only succeeds in turning an abandoned day into a very disrupted one. They can be forgiven for asking, “why take the risks involved when heroic effort to keep things going will still look rubbish to the media?” All of this means that the disruption we see following heavy snow is an entirely rational outcome. Unless the frequency of these conditions increase significantly in the coming decades, I cannot see this changing. In an ideal world this rationale would be understood by the population at large, media and stakeholders.

For those who say we used to do better in BR days, I would acknowledge that this is probably true, but at least a bit easier with one controlling organisation directing all staff (all hands to the pumps as others have said). The downside is that the people travelling or working to enabling travel were clearly put at a greater level of risk (taking account of the road journeys to / from the station) than is now accepted, while the incentives working on the multiple organisations involved in today’s rail industry give them little reason to make a huge effort

 

[6Gman]

There are MML stories later on - but should save them for my book , if I ever get to write it....

Write it! Write it!

 

[furnessvale]

Then there are the emergency services. Over the last few decades, it has become apparent to them, that road accidents, deaths and injuries spike during heavy snow episodes, the additional hazards and unfamiliar population make that inevitable.

Of course, on the railway such an attitude would be totally unacceptable. If the railway cannot run safely, it stops running, end of.

Just look at the classic example of high HGVs in windy weather. Other than the major bridges, they are allowed to continue running but the car driver is advised to stay indoors because there is a danger of a high HGV being blown over and killing him.

 

[EAD]

Depends on the type of skiing. Downhillers prefer it hard to icy, as that is quicker. Slalom is best with a little recent snow as it is then grippy. The worst snow for recreational skiers is icy, particularly in mornings in spring when there is a lot of freeze /thaw.

Re the "wrong type of snow" comment - it was actually the journalist who said it. The BR man on the other end of it was Terry Worrall, who agreed (with a smile).

Just on the skiing question, a lot of work goes into course preparation. At FIS Wold Cup level this includes specifically ensuring it is not too snowy and courses will indeed be "iced" as needed at the direction of the course setter. As Bald Rick points out downhill is prepared to be the hardest packed and so iciest. One function of the ski edges in the turn is that they "cut" the snow through their pressure and it essentially refreezes afterwards, so a function of skiers passing the gates on the racing line is that it gets rutted and icier/potentially faster as more pass.

While bad conditions can call off a race, there is also the issue of a change in conditions which means it is not a level field - indeed often a heavy snowfall will see lots of work to clear the course back to hard pack for a race as that is what a race needs and it ensures a more even playing field. Of course there is only so much you can do with mother nature, but there is no substitute for people being up early and preparing the course.

 

[Bald Rick]

Significant snow is infrequent in lowland England and Wales more or less all the way up to the Southern Uplands, whereas it is fairly common on the uplands down as far as the Peak District and the Brecon Beacons. Lowland snow is often characterised by a light fall that persists for a short time. When it is, the equipment and procedures used for icy weather in general, will work fairly well for snow – gritting surfaces, de-icing, point heaters etc.

These procedures have been refined and some weaknesses dealt with, although often after painful lessons such as the need to shield air intakes from snow ingress, such as the infamous ‘wrong kind of snow’ and the more recent Eurostar snow ingress issue. Weather forecasts are much more accurate and helpful to the industry than twenty years ago and (as others have noted) they are used throughout the industry to aid planning and preparation. There will still be problems, but they won’t generally amount to network paralysis.

It is more substantial snow falls that are the more troublesome. At the altitude of most railway lines, nowhere in the UK are such heavy falls a frequent occurrence. Sure, as you go north the risk does increase, hence the concentration of the specific resources further north, where they are more likely to be put to good use there. However, even around Inverness, the snow-ploughs can easily go a whole winter with just training runs.

In order to cope with heavy falls comprehensively, expensive equipment must be purchased and additional procedures added. These would require costly maintenance and continuous training to maintain competence but with little actual application. As any train driver will tell you, keeping skilled with many different fault finding routines that you may only require once in five years is a demanding requirement. When finally called upon, such processes won't benefit from any learning curve of repeated experience and staff will inevitably take more time to do the task than they would if familiar. As others have noted, even countries with regular heavy snow find that the first such events of the year are quite disruptive as everyone relearns how to cope. The number of trains per year delayed by snow in Norway and Sweden is certainly not zero! Being well prepared for heavy snow would therefore have a significant ongoing cost which is unlikely to be justified by occasional application. In short, it is rational to just have a day with little or no service once every five years. This fact is rarely stated as it isn’t an easy sell...

Then there are the emergency services. Over the last few decades, it has become apparent to them, that road accidents, deaths and injuries spike during heavy snow episodes, the additional hazards and unfamiliar population make that inevitable. This of course drives up their workload at a time when they (like everyone else) find working more difficult. They are incentivised to minimise accidents such and injuries, while they are not accountable for the loss of productivity or disruption to the economy. This means that they have a strong incentive to ‘advise against travel’, even when holistic consideration of other considerations might suggest a higher threshold.

This advice then sets off a chain reaction. School children may mostly have short walkable journeys, but a teacher coming 10 miles can legitimately take account of such advice. Faced with a likelihood of either too few staff members and possible last minute closure, schools are then incentivised to make a decision on closing quite early to avoid unnecessary journeys where other members of staff and parents discover that a school is closed on arrival. At this stage all sorts of people (including railway staff) face both advice not to travel and in many cases a need to provide unplanned child care and thus the working day grinds rapidly to a halt.

Railway companies have also discovered that making a huge effort to operate immediately after heavy snow fall only succeeds in turning an abandoned day into a very disrupted one. They can be forgiven for asking, “why take the risks involved when heroic effort to keep things going will still look rubbish to the media?” All of this means that the disruption we see following heavy snow is an entirely rational outcome. Unless the frequency of these conditions increase significantly in the coming decades, I cannot see this changing. In an ideal world this rationale would be understood by the population at large, media and stakeholders.

For those who say we used to do better in BR days, I would acknowledge that this is probably true, but at least a bit easier with one controlling organisation directing all staff (all hands to the pumps as others have said). The downside is that the people travelling or working to enabling travel were clearly put at a greater level of risk (taking account of the road journeys to / from the station) than is now accepted, while the incentives working on the multiple organisations involved in today’s rail industry give them little reason to make a huge effort

What an excellent post, thank you for taking the time to write it.

 

[Wivenswold]

This keen weather forecaster is becoming increasingly concerned about the forecast for the next week. Heavy snow expected over much of Scotland and down the North East Coast by the end of the week. Snow could also settle on any high ground in the UK too. The main problem (in my opinion) will be the freezing overnight temperatures with areas of the midlands likely to see -4, possibly as low as -6.

Beyond Friday there's much too uncertainty to make any predictions, the computer models varying between "Snowmageddon" and a slow, murky return to milder conditions.

Worth keeping a close eye on the forecast as there's likely to be some signal issues, closed rural lines, frozen points etc. I thought it would be useful to have a thread for general discussion on it.

BTW, If you read or hear that it's going to be the coldest, hottest, windiest, wettest winter on record, ignore it. Not even the experts can reliably forecast beyond 7-10 days.

 

[Wivenswold]

After our little taste of winter we're set for round 2 from Thursday and this one is more organised.

If you're travelling Thursday to Monday be aware that there's a chance of some disruptive snow and freezing overnight temperatures. Further updates to follow.

 

[tsr]

Slippery platform announcement is on speed dial...

(Actually it always is...)

 

[DarloRich]

That last photo reminds me of a report from the driver of a snowplough duty during a much more recent winter on the Buxton branch, who elected to call it a day and turn back because the drifts were above the level of the cab windows.

There's a dramatic aerial photo on the wall of the Bridge of Orchy hotel, taken sometime in the early eighties, of a class 37 hauled passenger train thoroughly embedded in drifts on the nearby West Highland line.

I will give him that one

 

[al78]

Of course, on the railway such an attitude would be totally unacceptable. If the railway cannot run safely, it stops running, end of.

Just look at the classic example of high HGVs in windy weather. Other than the major bridges, they are allowed to continue running but the car driver is advised to stay indoors because there is a danger of a high HGV being blown over and killing him.

Yes it has always been the case that safety attitudes on the roads are far more lax than would be in any industry where heavy, potentially dangerous machinery is involved. As far as high winds are concerned, the danger to car drivers is not just from HGV's, that is probably one of the lower risks. More likely to be issues are falling trees and flying debris, plus if the winds are very strong, keeping control of the car can become an issue.

 

[Wivenswold]

I agree with the point about safety attitudes on roads. In modern times were we are conditioned to think in binary terms (i.e. Socialist/Capitalist, Left/Right, Remain/Leave, Good/Bad, Deal/No Deal etc) in the minds of some drivers it's either heavy snow or it's all clear.

I've seen some pretty horrific accidents when there's been a tiny covering of snow or none at all. Even if there's no visible trigger and the dew point is below 0, then any unmodified (eg unsalted) surface moisture is freezing and therefore a threat.

The attitude of some customers can be summarised by a young lady's twitter feed that I saw a few years ago "Big night out tonight", "Better not snow like they said", "Yeah, they said disruption likely, that'll be typical" "Snowing! Trains better be running", "WTF, my trains cancelled. Didn't Abellio see the forecast? #shambles".

 

[EssexGonzo]

You do have to run trains overnight to keep the contact wire free from ice.

I remember in the prolonged snow in 2010, hearing the EMUs running all night through the Shenfield cutting. This must have been the reason. I live 300m from the cutting and generally tend not to hear many trains so the sound of electric trains beyond 0130-ish is unusual.

 

[philthetube]

Apart from snow above the rail the worst weather for third rail systems is snow which washes off the de-icing fluid followed by more snow which settles then a hard frost which freezes the later snow onto the rail.

 

[al78]

Apart from snow above the rail the worst weather for third rail systems is snow which washes off the de-icing fluid followed by more snow which settles then a hard frost which freezes the later snow onto the rail.

This is the problem with snow in the UK, it tends to fall in marginal conditions near the freezing point, so when it falls, it thaws a bit during the day then re-freezes overnight. This leads to black ice on the roads and icing on the third rail acting as an insulator. It might be easier if we had proper continental winters with temperatures 10-20C colder, the snow would be dry and powdery and would not stick to surfaces, rather than the heavy wet flakes that settle then thaw/refreeze into ice.

 

[al78]

Out of interest, what measures are taken to try and keep the line open over the Drumochter pass? That climbs up to 450m asl and must occasionally suffer from heavy snow and drifting. Similarly, the line over Rannoch moor is over 300m asl and must similarly get hit with heavy snow occasionally.

 

[Highlandspring]

MSP patrolling when required.