Landslips

[40C]

The Scunthorpe landslip appears to be in the cutting just West of the station. There is a T3 showing on Traksy.

 

[Mcr Warrior]

And for natures next performance a landslip between Scunthorpe and Doncaster means that services are currently unable to run between these stations.

As a result, trains will be cancelled or revised.

This caused a little bit of confusion on the west side of the Pennines yesterday. The departure board displays were showing many TPE services (presumably those originating from Cleethorpes?) bound to/from Liverpool Lime Street (via Manchester Piccadilly, then Warrington Central) as "cancelled", whereas they were seemingly still running (reinstated?), but only from/as far as Sheffield.

 

[yoyothehobo]

A lot of earthworks failures are caused by the strain softening of the material that they are made of, this is a seasonal year on year loss in the overall strength of the material, and can be particularly affected by wet weather, particularly the wetter weather we are getting now, with the material the embankment is constructed of eventually getting to a point where the embankment will fail. The problem is we have incredibly old earthworks that were poorly designed due to a limited/non existent understanding of soil mechanics.

Of the nearly 50 earthworks i have visited over the last 2 years, with issues, the number which have issues related to trees is less than 3. The biggest risk from trees is from tree fall and leaf fall. This whole its the tree issue, does seem to stink a bit of people having rose tinted memories of steam trains in the 60s.

By far the biggest impact on earthworks is drainage and rainfall and age.

 

[59CosG95]

Don't believe this made it into the public eye, but the Old Dalby Test Track was also affected by a landslip. Civils works are ongoing and OLE replacement in the affected spans is also planned.

 

[swt_passenger]

Don't believe this made it into the public eye, but the Old Dalby Test Track was also affected by a landslip. Civils works are ongoing and OLE replacement in the affected spans is also planned.

I doubt the public would care about Old Dalby, but it did result in a forum thread at the time:

Old Dalby Test Track

I gather the track has been taken out of use due to subsidence. Does anyone have any further details?

www.railforums.co.uk

 

[Ploughman]

I think there is a piece about it in the May Modern Rail.

 

[YorkshireBear]

Line to Scunthorpe now reopened

 

[JD2168]

Line to Scunthorpe now reopened

Also has a temporary speed restriction with the bank being watched in case of further disruption.

 

[Cletus]

Interesting article about the Dover to Folkestone line (if you can see around all of the adverts)

The huge landslide that pushed railway 50 metres towards the sea – could it happen again?

After months of heavy rain, a Kent railway line running through an active landslide is being watched closely by engineers.

www.kentonline.co.uk

The coastal railway line between Folkestone and Dover is one of the most stunning in Britain, but it is also one of the most challenging to operate – reputed to be the most expensive stretch to maintain in the whole country.

It is built through a landscape that is continually at threat of landslides and ground movement, as Rhys Griffiths discovered when he visited the site with Network Rail to learn more about the challenges of keeping this tricky track open…

We are standing on a small chalk ridge overlooking the Warren, a site of special scientific interest just outside Folkestone, with cliffs to our right and the English Channel to our left.

Birdsong is the only soundtrack until the rhythmic rattle of an approaching train fills the air as it passes along the line below, which bisects this stunning coastal landscape.

It’s hard not to marvel at the feat of engineering which, almost 200 years ago, saw this railway line driven through the chalk cliffs between two port towns. It is also easy to wonder at the wisdom of constructing the line through what is to this day an active landslide.

We have come to meet Derek Butcher, principal geotechnical engineer at Network Rail, who is closely acquainted with this stretch of the county’s rail network. He is open in his acknowledgment that, were a railway between Folkestone and Dover being built today, you would be unlikely to choose this route for your tracks.

“It is 180 years old, which actually only makes it 20 years newer than the Stockton to Darlington railway line, which is the first UK railway line.

“This makes it incredibly difficult to manage. It's an old piece of line, constructed not in the ways that we would construct railway lines today. It's been constructed through a chalk landscape. It runs next door to the sea between Folkestone and Dover, which makes it quite challenging to run and maintain.”

A 3km stretch of the coast at the Warren is formed of what is known by the experts as a rotational landslide, described by the British Geological Survey as one of the largest anywhere on the English coast. Here a layer of chalk sits over a layer of gault clay, with the chalk from the ‘high cliff’ prone to slide down to form the ‘sea cliff’ nearest the water’s edge.

The risk of a landslide grows when the ground absorbs rainwater. And since England has only recently emerged from its wettest 18-month period on record, the potential for further landslides is clearly increased.

To understand the potentially catastrophic consequences of a major landslide on the railway, you only have to look back into the history books for examples of previous cliff collapses on this stretch.

“We’ve seen a number of instances of quite large landslips,” Mr Butcher says.

“There were large landslips in 1877 and 1915. The 1877 landslip killed two people. The 1915 landslip meant that the line was closed for three years. I think some of that was due to the war effort going on at the time.

“But certainly the railway was completely destroyed with the landslip and had to be rebuilt from the base level upwards.”

The 1915 landslide, which became known as the Great Fall, was so severe that it caused the railway line to shift 50m towards the sea as a section of the chalk cliffs collapsed after weeks of heavy rain. The kink in the line caused by the sudden shifting of the ground remains visible to this day, proving the severity of the cliff fall.

Mr Butcher discovered dramatic photographs of the aftermath of the landslide in a filing cabinet while moving offices some years back, and they show just how much damage can be caused to the railway by sudden shifting of the landscape around it.

"We believe the train pictured was alerted to the landslip by the signal box at Folkestone Junction and was slowed down,” Mr Butcher said at the time the photographs were unearthed.

“It found itself part on and part off the landslip. They were able to evacuate passengers who walked through the tunnel to Folkestone Junction station. There was a significant amount of movement following the train stopping. That’s why it looks so horrific."

The challenge posed by the rotational landslide at the Warren is two-fold. Firstly, it is active and ongoing. Secondly, it is of a scale that means a complete engineering solution to prevent the movement is impossible. This leaves Network Rail with a job which focuses on a combination of monitoring and maintenance.

“We've got an extensive monitoring regime for the Warren and the railway line itself,” Mr Butcher explains.

“We use something called Lidar, light detection and ranging, which is a laser scanning system which operates either from the air or from the ground.

“We have some remote systems as well, which were installed into the ground, some inclinometers which monitor vertical movement, and some extensometers at the top of the cliff, which monitor horizontal movement.

“By looking at all those different changes we can determine which areas are moving, by how much, whether it's increasing over time, and what we need to do with that information.”

The recent spell of prolonged wet weather has not only affected the railway line through the Warren, where a speed restriction is in place following ground movement, but also the cliffs further along the coast in Folkestone itself. The town’s Road of Remembrance is set to remain closed all year after sections of the cliff there fell away.

Wetter winters and drier summers, driven in part by climate change, pose a challenge to Network Rail when it comes to maintaining the entire rail system. But while in other locations engineering works can significantly reduce the chances of landslides impacting the railways, things are more tricky here at the Warren.

“One of the issues with this particular landslip is its depth of movement,” Mr Butcher explains.

“The movement that occurs here is about 70 metres below ground level, so that's really different to other locations that we might have stabilised during the winter, which are a very shallow amount of movement, typically two to three metres worth of movement.

“There we will intervene with sheet piles. We can install sheet piles to about 10 metres depth, typically - sometimes beyond that to 20 metres. But we would never be able to install piling down to 70 metres.

“It's just beyond the range at which those conventional techniques are able to be installed.

“So typically at Folkestone we are looking at a different approach. That regular maintenance and monitoring approach seems to have stood the test of time down at the Warren.”

Network Rail plans to address the line between Folkestone and Dover this summer, adding fresh ballast to the track bed to return the tracks to their previous position prior to the most recent ground movement.

This should then allow the existing speed restriction affecting services between the towns to be lifted. However, this work will not be able to be carried out until the chalk and clay have dried out sufficiently and the experts are convinced we have seen the last of the ground movement in the area.

In the event that the worst should happen, and a significant cliff collapse or ground movement is detected, sensors would relay that information to railway controllers in real-time – allowing them to immediately halt trains in the area of the potential danger.

With the Folkestone to Dover line’s 200th anniversary coming 20 years from now, let us hope we do not see a repeat of the terrible drama of the ‘Great Fall’.

This stretch of the railway may be expensive to maintain, but it is a scenic delight and a feat of engineering which should be enjoyed by generations to come.

Edit

Southeastern have just tweeted that the temporary speed restriction between Dover Priory and Folkestone has been withdrawn.

 

[snowball]

Article in the Observer

UK rail faces fight to stay on track as climate crisis erodes routes

Britain’s railways are spending billions on bolstering the tracks against geological movements caused by extreme weather. But technology and new infrastructure will not save every service

www.theguardian.com

Britain’s railways are spending billions on bolstering the tracks against geological movements caused by extreme weather. But technology and new infrastructure will not save every service
Gwyn Topham
Gwyn Topham, Transport Correspondent
Sun 19 May 2024 13.00 BST

Under the chalk cliffs east of Folkestone sits the Warren, a coastal wilderness largely owned by the railway, hosting a nature trail for walkers, as well as the Victorian rail line that runs on to Dover.

It is also, problematically for Network Rail, an active landslide. “Our monitoring here,” says Derek Butcher, principal geotechnical engineer for the southern region, “shows we’re actually moving ever closer to France – despite Brexit.”

The geological combination of permeable chalk above gault clay means this has long been a known risk area: a massive landslide in 1915 moved the tracks about 50 metres towards the sea, and the line stayed closed for nearly four years because manpower had been diverted to the first world war trenches. Although numerous sea defences and drains have been built since, the line has taken a battering again as a run of the wettest winters on record piled up in the past 10 years.

The Warren is just one of many risk sites. Unprecedented rainfall in the last 18 months – hot on the heels of record-breaking summer heat – has in every sense shifted the ground for the railway. Resilience to extreme weather of all kinds is a preoccupation in planning.

The kind of money that not long ago would have electrified a railway line is now going, in large part, down the drains. Network Rail has dedicated £2.8bn in the next five years simply to bolster Britain’s tracks against the changing climate – and its leaders have warned that it may never be enough to save all the routes that exist today.

Recorded landslips on the British railway alone have almost doubled in frequency, from 475 to 848 in the five years either side of 2019. At the Warren, recent movement of the earth is clearly visible on a large fault line that runs from the rail tracks to the sea.

“It’s opened up quite significantly over the last two months or so,” Butcher points out: in the footpath through the shrub, 20cm to 30cm of fresh bare earth is visible against the green of weeds; at sea level, a concrete apron built half a century ago to protect the beachfront from erosion is ruptured again. “And trains don’t need a lot of track movement to derail.”

While the trackside has been reinforced and fresh ballast laid, the undulation is clear on the line emerging between the tunnels here. For safety, a 20mph speed limit has been imposed and high-speed trains that reach 140mph a few miles north on their way to London now crawl along, the ends of the carriages visibly lifting and falling as they pass over the dip.

A 75-metre-deep inclinometer has been sunk into the earth and Network Rail engineers are out walking the tracks, checking for any further movement of the rails. More and more risk sites are now monitored remotely with sensors in the earth, but even large-scale mitigation work can only do so much.

Network Rail’s chief executive, Andrew Haines, says technology can help manage the effects, but adds bluntly: “We cannot infrastructure-build our way out of climate change. The price tag is too expensive and it’s too disruptive.”

Although the buckling rails seen in a sweltering July 2022 might become a more frequent concern as temperatures rise, the primary issue now is abnormally high rainfall. “It’s not a risk for a future – we are living climate change,” Haines says.

I've quoted about half of it.

 

[HSTEd]

Article in the Observer

UK rail faces fight to stay on track as climate crisis erodes routes

Britain’s railways are spending billions on bolstering the tracks against geological movements caused by extreme weather. But technology and new infrastructure will not save every service

www.theguardian.com

Well it increasingly seems that our only option IS to infrastructure build our way out of climate change.

The existing railway infrastructure is disintegrating already and warming is almost certain to breach 2.5 Celsius.

Whether Network Rail is capable of achieving what is needed is, however, another question.

 

[Killingworth]

Well it increasingly seems that our only option IS to infrastructure build our way out of climate change.

The existing railway infrastructure is disintegrating already and warming is almost certain to breach 2.5 Celsius.

Whether Network Rail is capable of achieving what is needed is, however, another question.

Surely more important to conserve resources to reinforce, improve and maintain the existing infrastructure than rebuilding some of the equally aged lines that have been closed for over 50 years.

 

[HSTEd]

Surely more important to conserve resources to reinforce, improve and maintain the existing infrastructure than rebuilding some of the equally aged lines that have been closed for over 50 years.

I wasn't talking about reopenings, I was talking about building new infrastructure. Such construction would be aimed at replacing the old infrastructure which probably can't be depended on long term.

 

[Killingworth]

I wasn't talking about reopenings, I was talking about building new infrastructure. Such construction would be aimed at replacing the old infrastructure which probably can't be depended on long term.

I'd agree.

 

[endecotp]

Article in the Observer

UK rail faces fight to stay on track as climate crisis erodes routes

Britain’s railways are spending billions on bolstering the tracks against geological movements caused by extreme weather. But technology and new infrastructure will not save every service

www.theguardian.com

Something that I spotted in that article was a reference to Holes Bay, which is part of Poole Harbour, a little to the West of Poole station. I wasn't aware of any issues there; does anyone know what they are referring to?

Here is the relevant bit:

Whether the instinct to repair should always be followed everywhere in future is a moot point, Constable suggests, citing routes like the Cambrian and Cumbrian coast lines, or Holes Bay near Poole. “It may be that it’s just not feasible from a technical or a financial perspective to maintain the railway in that area.

 

[swt_passenger]

Something that I spotted in that article was a reference to Holes Bay, which is part of Poole Harbour, a little to the West of Poole station. I wasn't aware of any issues there; does anyone know what they are referring to?

The Holes Bay causeway was repaired sometime within the last 10 years, I think what the article is suggesting is that it’s an example of a route where if it needed major repairs in the future then a diversion might have to be chosen instead.

 

[GRALISTAIR]

Whether Network Rail is capable of achieving what is needed is, however, another question.

They are more than capable. Three things are needed though.

1. Time
2. Money
3. Political will

 

[HSTEd]

They are more than capable. Three things are needed though.

1. Time
2. Money
3. Political will

Well the problem is that, even given these three things, Network Rail has hardly cultivated a reputation for succesful delivery of multi-billion pound projects.
Even the resignalling programme does not, last I checked, appear to actually be going well enough to meet the requirements Network Rail have set out.

They, and the railway industry more broadly, is not in the shape for the wholesale replacement of large quantities of dubious legacy infrastructure.
The necessary capability does not really exist.

 

[GRALISTAIR]

Well the problem is that, even given these three things, Network Rail has hardly cultivated a reputation for succesful delivery of multi-billion pound projects.
Even the resignalling programme does not, last I checked, appear to actually be going well enough to meet the requirements Network Rail have set out.

They, and the railway industry more broadly, is not in the shape for the wholesale replacement of large quantities of dubious legacy infrastructure.
The necessary capability does not really exist.

That is depressing and tragic when I think about it!

 

[FenMan]

Network Rail may not want to trumpet infrastructure works completed on time and within budget for fearing of drawing attention to, erm, the obvious, such as the GWR electrification shambles. And that's taking into account an unfit for purpose structure where Ford Fiesta jobs are priced at more than a fleet of top of the range Ferraris. It's a classic gravy train of bucketloads of taxpayers' money either being squandered or diverted into private hands - Branson and the dynamic duo at Stagecoach know/knew all too well about the latter.

If I was appointed Transport Minister in an incoming government I'd be asking SNCF and DBahn to show me how they do it and then demanding Network Rail puts forward a concrete action plan to achieve the same cost/performance levels within 12 months (I'm being hopelessly optimistic, but it's a starting point). Network Rail has long been addicted to hosing away massive public funding with far too little to show for it. This has to stop. To continue the way we are endangers the very railway itself.

 

[Mordac]

Network Rail may not want to trumpet infrastructure works completed on time and within budget for fearing of drawing attention to, erm, the obvious, such as the GWR electrification shambles. And that's taking into account an unfit for purpose structure where Ford Fiesta jobs are priced at more than a fleet of top of the range Ferraris. It's a classic gravy train of bucketloads of taxpayers' money either being squandered or diverted into private hands - Branson and the dynamic duo at Stagecoach know/knew all too well about the latter.

If I was appointed Transport Minister in an incoming government I'd be asking SNCF and DBahn to show me how they do it and then demanding Network Rail puts forward a concrete action plan to achieve the same cost/performance levels within 12 months (I'm being hopelessly optimistic, but it's a starting point). Network Rail has long been addicted to hosing away massive public funding with far too little to show for it. This has to stop. To continue the way we are endangers the very railway itself.

DB and SNCF don't have to deal with our insane planning system.

 

[30907]

If I was appointed Transport Minister in an incoming government I'd be asking SNCF and DB to show me how they do it and then demanding Network Rail puts forward a concrete action plan to achieve the same cost/performance levels within 12 months

Not the best examples to choose, given the state of their respective networks

 

[railfan99]

I think most people who post about trees on railway land are saying the opposite of that - too many trees have been allowed to grow and not enough are removed.

How likely are native English trees to fall onto tracks (or suddenly block driver visibility of signals and level crossing/speed restriction signs) in the event of heavy rain that saturates embankments and cuttings?

Some Australian eucalypts ('gum trees') tend to fall in such conditions, but I've looked at the root structures of plane and elm trees in my distant city and they seem sturdy, especially the former.

Ultimately we can't expect railways built by engineers with no modern engineering design tools to last forever, especially in the face of extreme weather like the wettest winter ever recorded.

What year do reliable climate records go back to?

Climates have changed through millennia. Trendy claims about so-called 'climate change' ignore this.

 

[HSTEd]

What year do reliable climate records go back to?

Climates have changed through millennia. Trendy claims about so-called 'climate change' ignore this.

Probably the mid nineteenth century.

Why the climate is changing doesn't particularly matter in this instance, the fact is that it is and the railway infrastructure built for the Victorian era cannot withstand it.

 

[snowball]

Climates have changed through millennia. Trendy claims about so-called 'climate change' ignore this.

Of course climates have changed through millennia. Thousands of careful climate scientists know that perfectly well and have devoted their careers to studying the evidence for it, and have come up with their predictions of climate change based on a detailed understanding of physics, chemistry, meterorology etc. Climate science has nothing whatsoever to do with "trendiness". If you think otherwise, you have been reading and believing too much disinformation from people who are either malicious or away with the fairies.

The Central England Temperature Record is one example of a good data set and goes back to 1659, with a day-by day record from 1722:

Central England temperature - Wikipedia

en.wikipedia.org

But there are numerous physical sources of climate information which go back thousands of years, such as tree rings from all over the world, ice cores from Greenland and Antarctica, fossil sea shells etc.

Here is a link to the main international body which produces the reports that politicians are so disgracefully slow to act on:

IPCC — Intergovernmental Panel on Climate Change

www.ipcc.ch