This was an interesting, well-edited video, and the graphics were helpful and appropriate. I'm also impressed that you were willing to do a half-hour walk to the viaduct site. That viaduct is one humungous structure!
Wow your smile when you seen the viaduct being built was priceless. And I am sure you smile will be just as big when you get to travel on it. I so remember this incident at Gerard’s Cross. 😊
Nicely covered Michael. Its good to see a young man enthused by big engineering projects. And they do not come much bigger than HS2. I wish schools would steer more students towards engineering (of all sorts). Well done ...
Glad to hear you enjoyed - and yes, given the engineering industry is facing a major skills shortage, anything that can be done to promote it would be a very good thing in my eyes!
Good summary of the Gerrards Cross tunnel collapse. I came home from London to Seer Green & Jordans (next station north after Gerrards Cross) on that evening, and went through the tunnel around 20 mins before it collapsed - it was raining hard that evening, so the rain would have been applying extra weight to the piled up fill. I remember the days of disruption while they cleared the tracks, and then worked out a safe way of letting trains back through.
@@MikeWillSee yes, that would be good. I know this is super-nerdy on my part but would it be possible to look at the HS2 Vent-shafts and Head-Houses in Greater London, at some point in the future?
@High Voltage Switcher I'm not sure how much I'd be able to see from the street considering they're likely surrounded by hoardings etc, but I definitely wouldn't rule it out either. Likely to be a while before any major future videos as I'm quite busy with schooling stuff at the moment but yes it's definitely something I'd consider doing in the future!
When I first saw the pictures shortly after the collapse I wrote on a railway forum that it looked like not enough fill had been placed at the sides of the arch to support. At the time I was strongly critiqued for saying this, but it looks like I may have been correct. If you catch a grain Northwards from here you will get to Birmingham Moor Street and then Birmingham Snow Hill Stations. Moor Street was not part of the original railway, it was added in the early 20th century, but originally the line into Snow Hill was in open cutting which was later covered over to enable some shops, the Great Western Arcade, to be built on top, a sort of 19th century version of what was done for the Tesco store.
That's really interesting, thank you, I never knew that! At some point I'd like to visit Moor Street/Snow Hill, so if/when I do, I'll be sure to mention that in the video!
I comment as a resident of the Gerrards Cross area, this development was not popular at the time, the tunnel collapse and blocking the rail line into London added insult to injury. The line was closed for several months and the Chiltern line was a major commuter route. The Tesco construction was halted for about 5 years while arguments continued, the white frame of the building shown in your video at 11:13 was left suspended across the cutting, as the spoil used to fill the cutting had to be removed from over the remaining tunnel sections to prevent further collapse. Eventually an alternative contractor was appointed, the framework removed, the tunnel repaired and they stated again. The road in front of Tesco goes over the original Victorian bridge, if you were to look carefully from the end of the platforms into the tunnel you can still see the brick supports of the road bridge.
I've heard that the whole thing was very controversial at the time! If nothing else, it seems unlikely that Tesco is going to try this anywhere else, given how expensive it was! Also in regards to your other point, I always found it surprising that they just sort of 'buried' the road bridge, rather than demolishing it and sending the road over the newly covered area. They probably had their reasons (cost, disruption etc.) but still it did strike me as rather odd. Anyway thank you for your comment! It's great to hear a local's perspective on the matter, and one that is clearly very knowledgeable on the subject!
I drive around the back of Harefield each week and they're doing a ton of HS2 work there, installing at least four new bridges and moving the entire road.
Yep, it's a substantial amount of engineering that's affecting a lot of places for sure. This all makes it a really interesting project to cover but of course massively controversial as well!
I came across this video by accident, and it has solved an interesting question that I have been asking myself for some time. On the M25 between the J16 and J17 there has been a recent "works" junction added and initially I thought it would become a services, lots of buildings in the Colne valley have gone up and a lot of electrical pylons have appeared, its not a quarry as I thought, and I now know what this is all about , the HS2 line construction, presumably there will be a tunnel here to get under the M25.
Correct! The tunnel goes not only under the M25, but under the Chilterns for 16km, which will make it the longest tunnel in GB (excluding maybe the Channel Tunnel but that doesn't really count since half of it is in france) The motorway exit you mentioned is a temporary thing to allow access to a massive compound which is being used to produce the concrete for both the tunnels and the viaduct shown in this video. They're producing the pre-cast concrete segments on-site to minimise carbon footprint from having to transport them long-distance, and once complete, the entire area will be demolished and rewilded.
Nice vid. The viaduct over the North Orbital Road is progressing slowly but surely - Last time I passed that way in November last year I noticed that the first section directly over the road was in place. Its is elegant and impressive as a piece of Civil Engineering. If the Chiltern line had been French it would have been electrified on the occasion of the switch from the DMUs of 1960s vintage to the new stock. After all it does connect two major cities.
Yep the Chiltern line is BADLY in need of some electrification, although there's no denying that being the last major mainline (into London at least) without any form of electrification does give it some character!
a breath of fresh air young man. Your a credit to your generation! keep up the good work! and to those that pick fault might I ask them what were they doing at your age ?
11:00 There's one detail about the mechanism that caused the collapse of that arch that need to be clarified. The weight on top of the arches caused the arch to push out laterally on both sides. As a shape, arches are exceptionally strong when in compression, but they collapse almost immediately when they lose their shape. As the sides pushed out, the amount of weight that the arch could withstand diminished until it reached that critical point.
What a good effort,re the tunnel collapse,I worked in that area at the time and a pal who drove a tipper lorry told me they where dumping wet infill onto the tunnel rings,which was far to heavy.This could just be hearsay though.Either way the Chiltern line was closed for months and I wonder who payed the damages which must have been huge.
Yes I've heard that somewhere as well. I think a lot of the damages were paid for by Tesco but I imagine at least some of the cost was also placed upon the contractor.
Thanks! Really enjoyed this video, which was very nicely produced all round. Lots of new information & an update on Dominique, which I haven't seen in person since last Summer. Despite HS2 closing my favourite walk for some 10 years, I'm also impressed with the engineering. Thanks again.
This reminds me of when I watched the early sections of the M25 being constructed near Chorleywood in the early 70s. I may still have a few pictiures some where - I will look for them!
I remember this happening and had assumed that I had simply missed the relevant follow up reports but um it seems that they'd been buried for 17 years. You can quite clearly see the crown buckling under the weight in the photographs though.
Yep. Although the reports were never formally released until quite recently, it was fairly obvious to most people in the engineering industry what had caused the collapse... Nonetheless, the investigative reports are still important as they help provide the context into what caused the collapse and why it happened, and provide engineers an opportunity to learn from them and not make the same mistakes in future.
Great presentation, Michael. It's interesting to see how much progress has been made on the Viaduct since the Google shot from October last year. I could drive up there in 20 minutes but you've saved me the bother :) At 3:25, where 'the path diverges into some woods', you are walking on the Old Uxbridge Road which connected Rickmansworth with Uxbridge. It is a centuries-old route, some of which is still paved and used to this day. The 'modern' main road to your left is the A412, also known as the North Orbital and was built sometime in the late 1930s or early 1940s. The North Orbital was to be a fast route through Hertfordshire and Essex, linking provincial towns far from the fringes of London and would have brought new opportunities to Hatfield, Hertford and Harlow. For one reason or another, it didn't really happen. There are probably other sections of the North Orbital that were completed and have since been 'repurposed' but this earliest stretch from Denham to Mill End gives you an idea of what they had planned. Forty years later the M25 became the actual 'Road to Hell'.
Ah that's really interesting to hear, so thank you for your comment! Funnily enough the road is still marked as being the North Orbital on Google Maps, along with a couple of other roads I've found in nearby towns such as Watford and St Albans, but they do seem a little disjointed and disconnected from each other, so it's not surprising to learn they were once part of a larger scheme! From some of the recent pictures that have been circulating around the internet, it looks like they've made a lot more progress on the viaduct since my last visit, with at least a third having been added to the length, so it may still be worth a trip out if you feel so inclined!
@@MikeWillSee Yep, I'll definitely take a drive out there next weekend. I know that road very well but haven't been that way for many years. Denham was a film production studio from 1936 to 1952 and thereafter, into the 1970s, was best known for recording film music, including the scores for Alfred Hitchcock's Vertigo, Chitty Chitty Bang Bang, and Star Wars. This all from Wiki :) The studio buildings were demolished in 1981. What's interesting to me is how many British film studios exist, or existed, in a quadrant centred on West London and fanning out into Buckinghamshire and Hertfordshire. I'll list some of them because it's raining and I'm bored: Beaconsfield Film Studios, Bucks.; Bray Studios, Berks.; Bushey Studios, Herts.; Rock Studios, MGM-British Studios, Heyday Films, Gate Studios, Elstree Film Studios, British and Dominions Imperial Studios - all in Borehamwood, Herts.; Cricklewood Studios, London; Ealing Studios, London; Isleworth Studios, London; Lime Grove Studios, London; Marylebone Studios, London; Pinewood Studios, Bucks.; Leavesden Film Studios, Herts.; West London Film Studios, Middx. etc ... You get the drift.
@@DaveFiggley wow yes that is a lot of film studios! Kind of a shame so many are lost now but I have heard there is some grand plan to boost the UK's film industry longer-term so it remains to be seen how that materialises. I am intrigued by your comment Denham's buildings having been demolished in 1981, as that leads me to wonder what the building I showed in this video was. Perhaps a more modern building on the same site? I'll have to do some more reading on the topic! Anyway if you're taking a trip out to the viaduct then I hope you enjoy!
@@MikeWillSee Yeah, the original buildings were very much in the 'Art Deco' style, popular in the 1930s. The building in your video is relatively modern (2007) but was maybe constructed with a nod to the style of the original studios. There is page on Wikipedia about Denham Film Studios which is worth reading.
Not a lot! The only reason I bolted them together is because they're relatively close together, and whilst I was visiting one, I decided to visit the other at the same time!
Excellent video - There was an aphorism that was current fifty years ago that "Geography is best learned through the soles of your boots", Well so is engineering. Can I commend the excellent You Tube videos produced by the Permanent Way Institute on HS2 particularly the one on Old Oak Common.
Crikey, I remember that tunnel collapse. If that had happen a minute later with regard to the train departing the station, this really would have been a brutal incident.
Impressive bridge building gear! It is going to be another fascinating high speed line. And unbelievable that they made such a mistake constructing that tunnel. But it is an interesting thing to create new building ground. Simply cover a rail line with a tunnel!
I've no idea why this came up when I typed youtube, but it was OK. I think you have room to be either more opinionated -- ie, talk more about what interests you -- or more journalistic -- ie, give different people's views of things. But I found it a refreshing watch.
would you know ,how long does take hs2 too put one block onto the viaduct,with that machine i was expecting the bridge to completed earlier than 2025, as below enjoyed your chat look forward to the next
According to an article I found in _New Civil Engineer_ 'The HS2 bridge building team is currently working at a rate of fitting one segment per day, or six per week. With 1,000 pieces to be placed, this would take until 2025, but HS2 has said it aims to finish the structure by the end of 2024. "We’ll go faster as we get used to it,” Ahulwalia assures. “And then it will be there for hundreds of years.”'
hs2 shouldn't be taking this long nor be this over budget, the fact it's deviating from its original brief is saddening, to have the whole of the north connected up could help England so much. at least construction hasn't ceased in its entirety
Yep it's extremely frustrating to see government short-termism messing up what should be a nationally strategic infrastructure project. Hopefully future governments are more competent on the matter!
Has it dawned on any one here that this is at the expense of NHS funding.? I was intiially quite impressed with the idea until it was quickly apparent that the project was wholey mal managed: that is to say, property is not being paid for properly. That is the very tip of the issues with HS2 thugs causing injuries to protesters, hS2 thugs bullying locals, HS2 thugs bothering young girls, harrassment of local people to reduce property values. The listr goes on. The Police are complicit with the corroption that is endemic with this fraud.
You'll be pleased to know that HS2 funding is not actually at expense of funding anything else, and anyone who tries to tell you that probably doesn't have your best interests at heart. In reality, HS2 funding is 'capital expenditure' meaning it's money that has been borrowed based off the future growth that HS2 is expected to bring. Meanwhile, NHS/police money is known as 'operational expenditure' meaning it's money that comes out of 'the pot' aka day-to-day tax revenue. As I said, anyone who tries to pit these against each other probably doesn't have your best interests at heart, and I think you'll find that most if not all HS2 supporters are also supporters of increased NHS funding, but it doesn't have to be one or the other. As for the management of the project, this is where some of your concerns are more legitimate. Unfortunately the deal with compulsory purchases not being paid for properly is not unique to HS2. From my understanding, the Government's systems for compulsory purchases is to pay LESS than a property is worth "in order to bring value to the taxpayer" which is bs as it actually means it gets caught up in legal disputes every time and costs a load more. Other European countries will pay _more_ than a property is worth to avoid this issue, and end up with a much lower overall cost as a result. Again, unfortunately that's a government policy, not a HS2 policy. As for the other points you raised, I think some of these may have been exaggerated somewhat, but they are still legitimate concerns. The only thing I can really say on the matter is that being a supporter of HS2 and being a supporter of the way it's being delivered by HS2Ltd. and government are NOT the same, and quite frankly many of us are appalled by what we're seeing. It's always important to call them out on it, whether you're personally supportive of, or opposed to the project.
Any Civil Engineers out there? I am an electrical power engineer so I have a question you ‘Civils’ may find daft. Why did they no put some props up inside the tunnel (Americans seem to call it ‘False-work’) to make sure it did not collapse from backfill errors. Seems like they assumed an almost perfect re-loading of the tunnel shell. Am I incorrect about that?
My guess would be because it was still an active railway underneath, and I imagine they were aiming to cause as little disruption as possible, but this is of course only a guess. Good question!
@@MikeWillSee Yes, I think you are probably correct. There was a similar constraint on a footbridge over a road in Florida a few years ago. They did not want to close the road as they were post tensioning the reinforcement wires/ bars in the concrete. Unfortunately cracks appeared in a node of the concrete and the bridge collapsed onto the open road tragically killing people (Nine I think). It was being built for Florida International University.
My kids both had birthdays at the H.O.A.C. Boating, abseiling, high wire tree top courses All gone Straight through the middle of the lot Uxbridge golf course Greenford driving range River Colne junction with grand Union totally destroyed all of it So what if they regenerate it It was fine as it was Ridiculous waste of time and money Bet it cost a load more and takes forever
Sorry to hear you've been personally affected by the project. The way I see it, these things are always going to be highly disruptive, but in my eyes worth it because of the huge capacity increase it will bring to the existing rail network which is vital in the fight against climate change. For example, the idea is that building the line can take express trains (that don't benefit locals) off existing lines such as the West Coast Main Line (and in this case, Chiltern Main Line), which means those lines can run more frequent, less crowded stopping services. I realise this is probably not much consolation to you personally, especially given how far off the opening is, I'm just giving you my perspective on the situation, and explaining how it _should_ unltimately benefit you in the future. I hope the attractions you mentioned are able to be reinstated or relocated some time soon.
@@MikeWillSee I get the fact of capacity and infrastructure and its a fantastic project I'm sure it would make a brilliant series on Quest or a TV channel of that nature But with so many people with their own fantastic ideas for what would be best for the country/world/commerce/global warming etc cetera Surely this is going against all the problems that we have created in the past century to save half hour on a journey My point is What's the point in the grand scheme of things It'll take forever to build use ridiculous amounts of resources, power,fuel, electricity also created from fuel Who agreed to this in the beginning cause no one I know was asked
@Richard Lock thank you again for your response, and glad you enjoyed the video! If it's alright I'll try and address some of the concerns you've raised and (again) give my perspective on it, but this may end up being a little long for a youtube comment! 1. If I've understood you correctly, it seems you're (quite rightly) concerned about the amount of resources going towards the project, especially given the climate crisis etc. as well as being concerned that the project appears to be about "growth for growth's sake" and time savings which I can totally understand. I think the important thing to remember is that the project is primarily about capacity, and the time savings are merely a side-benefit which should allow for a reduction in domestic aviation. Transport is the largest source of GHG emissions in the UK, and a report from _I think_ the Green Party (it may have been someone else) showed that even with an overall reduction in travel, and a transition towards electric cars etc, it is still necessary for rail to increase its modal share of transport from 10% to 20%. This would require the UK rail network to double its capacity by 2050, which is what HS2 is designed to do (but I'll talk about that later). On the topic of resources, I thought it's also worth mentioning that the entire carbon footprint for HS2 (both construction and operating once complete) is equivalent to about one month's worth of road emissions, and a trip from London to Edinburgh on HS2 will only have a carbon footprint of 5kg - even lower than the current 8kg for the same journey. This makes it by far the greenest way to be making that journey, and increased speeds should also encourage people out of planes. 2. Your other concern (from my understanding) appears to be the origins of the project, local consultation, and how it got approval etc. It goes back to capacity (as I was talking about earlier). The West Coast Mainline is the busiest mixed-traffic railway in Europe and already more-or-less at capacity. Forecasts are that passenger numbers are expected to continue growing so something needs to be done. A Network Rail report in 2008 was looking into this conundrum, and concluded that the best way to provide the required capacity increase would be a new dedicated high speed line between London and Birmingham initially, then future phases to take it further north. Various different designs for the line were considered and consulted upon over ~10 year period, but it only got serious in the last few years. There were local outreach and feedback programmes, but I'm not sure how successful they were. I know some modifications were made as a result of this (for instance it was decided that the Chiltern tunnel would be extended to be a few km longer to minimise surface impact on the AONB). The line was approved through the standard parliamentary process in which MPs vote on a bill, and had strong cross-party support.
@@MikeWillSee you know your stuff mate that's a fact I'm almost leaning towards agreeing with you shame someone like yourself wasn't leading the PR on this project I'm considering jumping on the Chiltern from West Ruislip and seeing it for myself Dunno if I really want to though
HS2 is definitely worth promoting - line we don't need, brutally cutting through cities and important environmental sites, built for no reason apart from bringing money to those involved. And brutally cut down from original plans to the point it serves no purpose (Old Oak Common end terminal, axing branches in the North etc)
Who said I was promoting it? This video is simply a construction update on the project. In any case it is worth promoting exactly because of comments like this which shows how much falsehood and misinformation surrounds the project. The line is needed because our railways are already at capacity, and need to carry more people in future to cope with the climate crisis The line has been designed to be very sensitive to urban and rural communities alike, and whilst some disruption is inevitable, it is FAR less than alternatives - the Lower Thames Crossing motorway affects roughly the same amount of woodland as HS2 despite being ~2% of the length of HS2 for example. The total area of ancient woodland lost to HS2 is less than 1/10,000th of the ancient woodland in this country. I semi-agree with your last point about the cuts, but Labour (who looks increasingly likely to be the next government) have committed to the full 'Y' shape of HS2, and the idea that Euston was cut from the plans was debunked almost immediately after the news 'broke'.
What a massive waste of money this project and a stain on the countryside and wildlife in this area, it’s actually shameful of this country to build this line it’s just not needed. For the residents of ruislip and Denham and the surrounding area it’s one massive eye sore. Shame on the government.
The idea that we don't need this line comes from the misconception that it's all about speed, when in reality it's about providing much needed capacity to our increasingly strained rail network by taking express trains off existing lines, freeing them up for far more local services. There's no doubt that any project of this scale is going to have some localised environmental impacts, but it is far smaller than comparable schemes (e.g. Lower Thames Crossing Motorway destroys more or less the same amount of woodland despite being approximately 2% of the length of HS2!) and HS2 have committed to massive rewinding projects meaning there will be a net gain in biodiversity along the route. In any case, the biggest threat to woodlands and the wildlife in this country is climate change, which this helps to address by providing an alternative to road and air travel by increasing rail capacity and driving modal shift.
@@MikeWillSee for 20 minutes saving it’s not worth it and after covid with people working online it’s proved it’s not worth it, also you might know the answer to this that the line might not get to Euston now which would be unbelievable and also to save money which it’s up to 120 billion to save 20 minutes wow there also now building the tunnels smaller which means that the trains can’t go through them so quick because of the air displacement which means that 20 minutes is lost, maybe you could clarify them points if you know. Good video btw.
@Craig Davenport first of all glad to hear you enjoyed the video! If it's alright with you I'll try and address some of the concerns you raised, but I do have a nasty habit of writing quite a lot so I apologise in advance! The idea that it's "just to save 20 minutes" is false for two reasons: 1. It's simply not true - the time savings between London and Birmingham are predicted to be 49 minutes! 2. The time savings are nothing but a side-benefit anyway, and the primary justification for the line has always been about capacity. I talked a little about this in my last comment but the problem with the current rail network is that intercity express trains and local stopping trains share the same line. When an Intercity train comes through it eats up loads of capacity since you have to leave a large gap in front of it so that it won't catch up with the slower trains. If you can place the express trains on their own dedicated line, it frees up the existing network for far more local, regional, and freight services. For the lines affected it allows a doubling or tripling of capacity. The idea that we don't need extra capacity due to an increase in home-working is also a bit of a falsehood. In reality, covid has simply accelerated the trend towards home-working, which had already been taken into account when predicting future transport needs. In any case, the latest transport statistics show that we are back to 90-100% of pre-covid ridership levels, which, even if a (slight) reduction from 2019 levels, is still about the same as passenger levels were roughly 10 years ago, when the need for the line was first identified. The idea that the line won't go to Euston is concerning, but thankfully false. The news was debunked almost as quickly as it broke, and Old Oak Common simply doesn't have the capacity to operate as a terminus. With that said, due to some poor decisions from those in government, the opening of Euston has been delayed from the original plan, meaning that it unfortunately won't open until a few years after the rest of the line. I hear the £120bn figure being thrown around a lot, but am yet to see a reliable source for it. Until I do, I'm assuming the figure has just been made up. The cost may well increase further since it is still being calculated, but most cost increases are owing to inflation rather than mismanagement of the project. In any case, the official budget for the whole line is still £88bn, which does sound like a lot, but from my understanding, it is the cost of the _full_ project, including the Eastern branch to Leeds, rather than just the London - Birmingham section. The other thing I think is important to note regarding cost is that it's not like they're spending £88bn a year - the cost is spread over several years if not decades, meaning the yearly budget is only about £3bn. To put that into context, approximately £8bn a year (if not more) is spent by network rail to maintain the existing network, and approximately £7bn a year is spent on subsidising domestic aviation (which is a bonkers policy decision knowing how much pollution that causes). Not sure where you heard that news about the tunnels being made smaller, I would treat that with extreme scepticism if I were you, as many of the tunnels have already started construction, and you can't exactly change the size of a tunnel boring machines half-way through! Those that haven't started construction are due to start soon, and as such the TBMs would have already been made for them. In any case, changing any element of the design this late on would save exactly £0, since there is a huge cost to redesign something last minute, even more so if it's already begun construction! The only way I could imagine you may have heard about the diameter of the tunnels being reduced is because some sections of the line _do_ have smaller diameter tunnels than other sections, but this has always been the case, rather than a last-minute cost-cutting measure. They may have opted for a smaller diameter tunnel if: a) the tunnel is quite short (as is the case with the Itchington Wood tunnel) b) the tunnel is designed for lower speeds (such as the approach into Euston) I realise I've written quite a lot but I hope this addresses some of the concerns you raised, and if you do have any further questions I'll do my best to answer them!
@@MikeWillSee yep fair enough as I say this is what I’ve heard and I’m always ready to listen to someone else’s opinions the only one I wouldn’t agree with you is climate change but that’s another issue, I also agree with the engineering aspect of these works is fantastic let’s hope they don’t have any collapses like the one in the video, will watch your future blogs videos as I’m also interested in the rail network as such and model railways.
HS2 is an environmental disaster of epic proportions & Britain's biggest infrastructure mistake in half a century. Thankfully, the Eastern leg & the Golborne link have now been scrapped & fingers crossed, the rest of this monstrous vanity project will never see the light of day.
Great video, thanks for that Michael! There's going to be a follow-up #RailNatter covering that HSE report soon!
I look forward to it, thanks for dropping by!
I have loved engineering all my life and I am so happy to see a young person like you so enthusiastic about engineering. Well done Michael.
Thanks Ken!
This was an interesting, well-edited video, and the graphics were helpful and appropriate. I'm also impressed that you were willing to do a half-hour walk to the viaduct site. That viaduct is one humungous structure!
Wow your smile when you seen the viaduct being built was priceless. And I am sure you smile will be just as big when you get to travel on it. I so remember this incident at Gerard’s Cross. 😊
I'm not sure there's enough space on my face for the smile that will arise when I get to actually ride it lol - glad to hear you enjoyed the video!
Thanks Michael for going out there and getting the shots. Great work!
Nicely covered Michael. Its good to see a young man enthused by big engineering projects. And they do not come much bigger than HS2. I wish schools would steer more students towards engineering (of all sorts).
Well done ...
Glad to hear you enjoyed - and yes, given the engineering industry is facing a major skills shortage, anything that can be done to promote it would be a very good thing in my eyes!
Good summary of the Gerrards Cross tunnel collapse. I came home from London to Seer Green & Jordans (next station north after Gerrards Cross) on that evening, and went through the tunnel around 20 mins before it collapsed - it was raining hard that evening, so the rain would have been applying extra weight to the piled up fill. I remember the days of disruption while they cleared the tracks, and then worked out a safe way of letting trains back through.
👍👌 Nice. This is the first non drone view of the Colne Valley Viaduct I have come across. Thanks for putting the time and effort in.🙂
Glad to hear you enjoyed! Maybe one day I'll get a drone as well to supplement the ground shots - everyone likes seeing more angles!
@@MikeWillSee yes, that would be good. I know this is super-nerdy on my part but would it be possible to look at the HS2 Vent-shafts and Head-Houses in Greater London, at some point in the future?
@High Voltage Switcher I'm not sure how much I'd be able to see from the street considering they're likely surrounded by hoardings etc, but I definitely wouldn't rule it out either.
Likely to be a while before any major future videos as I'm quite busy with schooling stuff at the moment but yes it's definitely something I'd consider doing in the future!
@@MikeWillSeeThanks. I know it’s a bit obscure but it was worth a try! Keep up the work 🙏
When I first saw the pictures shortly after the collapse I wrote on a railway forum that it looked like not enough fill had been placed at the sides of the arch to support. At the time I was strongly critiqued for saying this, but it looks like I may have been correct.
If you catch a grain Northwards from here you will get to Birmingham Moor Street and then Birmingham Snow Hill Stations. Moor Street was not part of the original railway, it was added in the early 20th century, but originally the line into Snow Hill was in open cutting which was later covered over to enable some shops, the Great Western Arcade, to be built on top, a sort of 19th century version of what was done for the Tesco store.
That's really interesting, thank you, I never knew that! At some point I'd like to visit Moor Street/Snow Hill, so if/when I do, I'll be sure to mention that in the video!
Well done, sir! Excellent post. Cheers.
Very nicely presented and edited! Highly enjoyable! 👍
I comment as a resident of the Gerrards Cross area, this development was not popular at the time, the tunnel collapse and blocking the rail line into London added insult to injury. The line was closed for several months and the Chiltern line was a major commuter route. The Tesco construction was halted for about 5 years while arguments continued, the white frame of the building shown in your video at 11:13 was left suspended across the cutting, as the spoil used to fill the cutting had to be removed from over the remaining tunnel sections to prevent further collapse. Eventually an alternative contractor was appointed, the framework removed, the tunnel repaired and they stated again. The road in front of Tesco goes over the original Victorian bridge, if you were to look carefully from the end of the platforms into the tunnel you can still see the brick supports of the road bridge.
I've heard that the whole thing was very controversial at the time! If nothing else, it seems unlikely that Tesco is going to try this anywhere else, given how expensive it was!
Also in regards to your other point, I always found it surprising that they just sort of 'buried' the road bridge, rather than demolishing it and sending the road over the newly covered area. They probably had their reasons (cost, disruption etc.) but still it did strike me as rather odd.
Anyway thank you for your comment! It's great to hear a local's perspective on the matter, and one that is clearly very knowledgeable on the subject!
A very professional video Michael . Well done.
I drive around the back of Harefield each week and they're doing a ton of HS2 work there, installing at least four new bridges and moving the entire road.
Yep, it's a substantial amount of engineering that's affecting a lot of places for sure. This all makes it a really interesting project to cover but of course massively controversial as well!
What a well presented & interesting video! Well done Michael....
Thanks for showing the progress on the new Railway. Luckily like you said, you will be riding on it one day. Regards 🇿🇦.
Interesting and well-produced video
Thank you very much, I'm glad you enjoyed!
I came across this video by accident, and it has solved an interesting question that I have been asking myself for some time. On the M25 between the J16 and J17 there has been a recent "works" junction added and initially I thought it would become a services, lots of buildings in the Colne valley have gone up and a lot of electrical pylons have appeared, its not a quarry as I thought, and I now know what this is all about , the HS2 line construction, presumably there will be a tunnel here to get under the M25.
Correct! The tunnel goes not only under the M25, but under the Chilterns for 16km, which will make it the longest tunnel in GB (excluding maybe the Channel Tunnel but that doesn't really count since half of it is in france)
The motorway exit you mentioned is a temporary thing to allow access to a massive compound which is being used to produce the concrete for both the tunnels and the viaduct shown in this video. They're producing the pre-cast concrete segments on-site to minimise carbon footprint from having to transport them long-distance, and once complete, the entire area will be demolished and rewilded.
Really enjoyed this vid!! I SO need to get to the viaduct before it's completed!! Keep the vids coming!! I'll watch all of em!!
Very informative and well put together. That's your video and hopefully the viaduct too! Sections of this post are very professional.
Thank you very much, I'm glad to hear you enjoyed!
Nice vid.
The viaduct over the North Orbital Road is progressing slowly but surely - Last time I passed that way in November last year I noticed that the first section directly over the road was in place. Its is elegant and impressive as a piece of Civil Engineering.
If the Chiltern line had been French it would have been electrified on the occasion of the switch from the DMUs of 1960s vintage to the new stock. After all it does connect two major cities.
Yep the Chiltern line is BADLY in need of some electrification, although there's no denying that being the last major mainline (into London at least) without any form of electrification does give it some character!
Well done , I came that way last year to see the construction, it’s impressive
a breath of fresh air young man. Your a credit to your generation! keep up the good work! and to those that pick fault might I ask them what were they doing at your age ?
this was really informative and interesting - thanks! also, excellent choice of crisps
11:00 There's one detail about the mechanism that caused the collapse of that arch that need to be clarified. The weight on top of the arches caused the arch to push out laterally on both sides. As a shape, arches are exceptionally strong when in compression, but they collapse almost immediately when they lose their shape. As the sides pushed out, the amount of weight that the arch could withstand diminished until it reached that critical point.
Yes I possibly should have tried to explain that a little better. Thanks for your comment!
What a good effort,re the tunnel collapse,I worked in that area at the time and a pal who drove a tipper lorry told me they where dumping wet infill onto the tunnel rings,which was far to heavy.This could just be hearsay though.Either way the Chiltern line was closed for months and I wonder who payed the damages which must have been huge.
Yes I've heard that somewhere as well. I think a lot of the damages were paid for by Tesco but I imagine at least some of the cost was also placed upon the contractor.
Thanks! Really enjoyed this video, which was very nicely produced all round. Lots of new information & an update on Dominique, which I haven't seen in person since last Summer. Despite HS2 closing my favourite walk for some 10 years, I'm also impressed with the engineering. Thanks again.
Great video thanks 👍
Great video! Well put together informative vlog!
Very informative, well done.
This reminds me of when I watched the early sections of the M25 being constructed near Chorleywood in the early 70s. I may still have a few pictiures some where - I will look for them!
I remember this happening and had assumed that I had simply missed the relevant follow up reports but um it seems that they'd been buried for 17 years. You can quite clearly see the crown buckling under the weight in the photographs though.
Yep. Although the reports were never formally released until quite recently, it was fairly obvious to most people in the engineering industry what had caused the collapse...
Nonetheless, the investigative reports are still important as they help provide the context into what caused the collapse and why it happened, and provide engineers an opportunity to learn from them and not make the same mistakes in future.
Brilliant video, I work all over HS2, an amazing project to be part of
Great video mate. You are in a very unique time, for you this is your future and it’s history in the making
Great presentation, Michael. It's interesting to see how much progress has been made on the Viaduct since the Google shot from October last year. I could drive up there in 20 minutes but you've saved me the bother :)
At 3:25, where 'the path diverges into some woods', you are walking on the Old Uxbridge Road which connected Rickmansworth with Uxbridge. It is a centuries-old route, some of which is still paved and used to this day.
The 'modern' main road to your left is the A412, also known as the North Orbital and was built sometime in the late 1930s or early 1940s. The North Orbital was to be a fast route through Hertfordshire and Essex, linking provincial towns far from the fringes of London and would have brought new opportunities to Hatfield, Hertford and Harlow. For one reason or another, it didn't really happen.
There are probably other sections of the North Orbital that were completed and have since been 'repurposed' but this earliest stretch from Denham to Mill End gives you an idea of what they had planned. Forty years later the M25 became the actual 'Road to Hell'.
Ah that's really interesting to hear, so thank you for your comment!
Funnily enough the road is still marked as being the North Orbital on Google Maps, along with a couple of other roads I've found in nearby towns such as Watford and St Albans, but they do seem a little disjointed and disconnected from each other, so it's not surprising to learn they were once part of a larger scheme!
From some of the recent pictures that have been circulating around the internet, it looks like they've made a lot more progress on the viaduct since my last visit, with at least a third having been added to the length, so it may still be worth a trip out if you feel so inclined!
@@MikeWillSee Yep, I'll definitely take a drive out there next weekend. I know that road very well but haven't been that way for many years.
Denham was a film production studio from 1936 to 1952 and thereafter, into the 1970s, was best known for recording film music, including the scores for Alfred Hitchcock's Vertigo, Chitty Chitty Bang Bang, and Star Wars. This all from Wiki :) The studio buildings were demolished in 1981.
What's interesting to me is how many British film studios exist, or existed, in a quadrant centred on West London and fanning out into Buckinghamshire and Hertfordshire.
I'll list some of them because it's raining and I'm bored: Beaconsfield Film Studios, Bucks.; Bray Studios, Berks.; Bushey Studios, Herts.; Rock Studios, MGM-British Studios, Heyday Films, Gate Studios, Elstree Film Studios, British and Dominions Imperial Studios - all in Borehamwood, Herts.; Cricklewood Studios, London; Ealing Studios, London; Isleworth Studios, London; Lime Grove Studios, London; Marylebone Studios, London;
Pinewood Studios, Bucks.; Leavesden Film Studios, Herts.; West London Film Studios, Middx. etc ...
You get the drift.
@@DaveFiggley wow yes that is a lot of film studios! Kind of a shame so many are lost now but I have heard there is some grand plan to boost the UK's film industry longer-term so it remains to be seen how that materialises.
I am intrigued by your comment Denham's buildings having been demolished in 1981, as that leads me to wonder what the building I showed in this video was. Perhaps a more modern building on the same site? I'll have to do some more reading on the topic!
Anyway if you're taking a trip out to the viaduct then I hope you enjoy!
@@MikeWillSee Yeah, the original buildings were very much in the 'Art Deco' style, popular in the 1930s. The building in your video is relatively modern (2007) but was maybe constructed with a nod to the style of the original studios.
There is page on Wikipedia about Denham Film Studios which is worth reading.
@@DaveFiggley thanks, I'll be sure to give it a read!
Gerrards cross was years ago !! What have the two got to do with each other?
Not a lot! The only reason I bolted them together is because they're relatively close together, and whilst I was visiting one, I decided to visit the other at the same time!
Great video though mate
Shows just how much destruction it has caused so far
Excellent video - There was an aphorism that was current fifty years ago that "Geography is best learned through the soles of your boots", Well so is engineering. Can I commend the excellent You Tube videos produced by the Permanent Way Institute on HS2 particularly the one on Old Oak Common.
Great narration. And wth were those backfillers thinking
Crikey, I remember that tunnel collapse. If that had happen a minute later with regard to the train departing the station, this really would have been a brutal incident.
Yep, it's amazing (and incredibly lucky) how many near misses occur on the railway!
The shocking thing is that it took 17 years for the info of what happened to be dragged out of them.
Impressive bridge building gear! It is going to be another fascinating high speed line. And unbelievable that they made such a mistake constructing that tunnel. But it is an interesting thing to create new building ground. Simply cover a rail line with a tunnel!
I've no idea why this came up when I typed youtube, but it was OK. I think you have room to be either more opinionated -- ie, talk more about what interests you -- or more journalistic -- ie, give different people's views of things. But I found it a refreshing watch.
Yeah this video seems to have reached a much broader audience than I'm used to with my videos, so your feedback is appreciated!
Brilliant Video Micheal. Camera work at the start was a tad shakey but apart from that 10/10.
Turns out holding a camera steady on the Central line is harder than one would think! Glad to hear you enjoyed the video!
Good video, Michael. It's very well researched and informative. Keep up the good work fella.
Good job, well done.
would you know ,how long does take hs2 too put one block onto the viaduct,with that machine i was expecting the bridge to completed earlier than 2025, as below enjoyed your chat look forward to the next
According to an article I found in _New Civil Engineer_ 'The HS2 bridge building team is currently working at a rate of fitting one segment per day, or six per week. With 1,000 pieces to be placed, this would take until 2025, but HS2 has said it aims to finish the structure by the end of 2024. "We’ll go faster as we get used to it,” Ahulwalia assures. “And then it will be there for hundreds of years.”'
hs2 shouldn't be taking this long nor be this over budget, the fact it's deviating from its original brief is saddening, to have the whole of the north connected up could help England so much. at least construction hasn't ceased in its entirety
Yep it's extremely frustrating to see government short-termism messing up what should be a nationally strategic infrastructure project. Hopefully future governments are more competent on the matter!
Great vid - but it's obvious that the line needs to be electrified - from that ghastly dirty diesel noise alone...
Yep, the line should have been electrified a long time ago!
Has it dawned on any one here that this is at the expense of NHS funding.?
I was intiially quite impressed with the idea until it was quickly apparent that the project was wholey mal managed: that is to say, property is not being paid for properly.
That is the very tip of the issues with HS2 thugs causing injuries to protesters, hS2 thugs bullying locals, HS2 thugs bothering young girls, harrassment of local people to reduce property values. The listr goes on.
The Police are complicit with the corroption that is endemic with this fraud.
You'll be pleased to know that HS2 funding is not actually at expense of funding anything else, and anyone who tries to tell you that probably doesn't have your best interests at heart.
In reality, HS2 funding is 'capital expenditure' meaning it's money that has been borrowed based off the future growth that HS2 is expected to bring. Meanwhile, NHS/police money is known as 'operational expenditure' meaning it's money that comes out of 'the pot' aka day-to-day tax revenue.
As I said, anyone who tries to pit these against each other probably doesn't have your best interests at heart, and I think you'll find that most if not all HS2 supporters are also supporters of increased NHS funding, but it doesn't have to be one or the other.
As for the management of the project, this is where some of your concerns are more legitimate. Unfortunately the deal with compulsory purchases not being paid for properly is not unique to HS2. From my understanding, the Government's systems for compulsory purchases is to pay LESS than a property is worth "in order to bring value to the taxpayer" which is bs as it actually means it gets caught up in legal disputes every time and costs a load more. Other European countries will pay _more_ than a property is worth to avoid this issue, and end up with a much lower overall cost as a result. Again, unfortunately that's a government policy, not a HS2 policy.
As for the other points you raised, I think some of these may have been exaggerated somewhat, but they are still legitimate concerns. The only thing I can really say on the matter is that being a supporter of HS2 and being a supporter of the way it's being delivered by HS2Ltd. and government are NOT the same, and quite frankly many of us are appalled by what we're seeing. It's always important to call them out on it, whether you're personally supportive of, or opposed to the project.
Any Civil Engineers out there? I am an electrical power engineer so I have a question you ‘Civils’ may find daft. Why did they no put some props up inside the tunnel (Americans seem to call it ‘False-work’) to make sure it did not collapse from backfill errors. Seems like they assumed an almost perfect re-loading of the tunnel shell. Am I incorrect about that?
My guess would be because it was still an active railway underneath, and I imagine they were aiming to cause as little disruption as possible, but this is of course only a guess. Good question!
@@MikeWillSee Yes, I think you are probably correct. There was a similar constraint on a footbridge over a road in Florida a few years ago. They did not want to close the road as they were post tensioning the reinforcement wires/ bars in the concrete. Unfortunately cracks appeared in a node of the concrete and the bridge collapsed onto the open road tragically killing people (Nine I think). It was being built for Florida International University.
My kids both had birthdays at the H.O.A.C.
Boating, abseiling, high wire tree top courses
All gone
Straight through the middle of the lot
Uxbridge golf course
Greenford driving range
River Colne junction with grand Union totally destroyed all of it
So what if they regenerate it
It was fine as it was
Ridiculous waste of time and money
Bet it cost a load more and takes forever
Sorry to hear you've been personally affected by the project.
The way I see it, these things are always going to be highly disruptive, but in my eyes worth it because of the huge capacity increase it will bring to the existing rail network which is vital in the fight against climate change. For example, the idea is that building the line can take express trains (that don't benefit locals) off existing lines such as the West Coast Main Line (and in this case, Chiltern Main Line), which means those lines can run more frequent, less crowded stopping services.
I realise this is probably not much consolation to you personally, especially given how far off the opening is, I'm just giving you my perspective on the situation, and explaining how it _should_ unltimately benefit you in the future. I hope the attractions you mentioned are able to be reinstated or relocated some time soon.
@@MikeWillSee I get the fact of capacity and infrastructure and its a fantastic project
I'm sure it would make a brilliant series on Quest or a TV channel of that nature
But with so many people with their own fantastic ideas for what would be best for the country/world/commerce/global warming etc cetera
Surely this is going against all the problems that we have created in the past century to save half hour on a journey
My point is
What's the point
in the grand scheme of things
It'll take forever to build use ridiculous amounts of resources, power,fuel, electricity also created from fuel
Who agreed to this in the beginning cause no one I know was asked
Again love the fact you've put in so much effort it's a great watch
Looking forward to more of your work
@Richard Lock thank you again for your response, and glad you enjoyed the video!
If it's alright I'll try and address some of the concerns you've raised and (again) give my perspective on it, but this may end up being a little long for a youtube comment!
1. If I've understood you correctly, it seems you're (quite rightly) concerned about the amount of resources going towards the project, especially given the climate crisis etc. as well as being concerned that the project appears to be about "growth for growth's sake" and time savings which I can totally understand.
I think the important thing to remember is that the project is primarily about capacity, and the time savings are merely a side-benefit which should allow for a reduction in domestic aviation. Transport is the largest source of GHG emissions in the UK, and a report from _I think_ the Green Party (it may have been someone else) showed that even with an overall reduction in travel, and a transition towards electric cars etc, it is still necessary for rail to increase its modal share of transport from 10% to 20%. This would require the UK rail network to double its capacity by 2050, which is what HS2 is designed to do (but I'll talk about that later).
On the topic of resources, I thought it's also worth mentioning that the entire carbon footprint for HS2 (both construction and operating once complete) is equivalent to about one month's worth of road emissions, and a trip from London to Edinburgh on HS2 will only have a carbon footprint of 5kg - even lower than the current 8kg for the same journey. This makes it by far the greenest way to be making that journey, and increased speeds should also encourage people out of planes.
2. Your other concern (from my understanding) appears to be the origins of the project, local consultation, and how it got approval etc.
It goes back to capacity (as I was talking about earlier). The West Coast Mainline is the busiest mixed-traffic railway in Europe and already more-or-less at capacity. Forecasts are that passenger numbers are expected to continue growing so something needs to be done. A Network Rail report in 2008 was looking into this conundrum, and concluded that the best way to provide the required capacity increase would be a new dedicated high speed line between London and Birmingham initially, then future phases to take it further north.
Various different designs for the line were considered and consulted upon over ~10 year period, but it only got serious in the last few years.
There were local outreach and feedback programmes, but I'm not sure how successful they were. I know some modifications were made as a result of this (for instance it was decided that the Chiltern tunnel would be extended to be a few km longer to minimise surface impact on the AONB).
The line was approved through the standard parliamentary process in which MPs vote on a bill, and had strong cross-party support.
@@MikeWillSee you know your stuff mate that's a fact
I'm almost leaning towards agreeing with you shame someone like yourself wasn't leading the PR on this project
I'm considering jumping on the Chiltern from West Ruislip and seeing it for myself
Dunno if I really want to though
The collapse was the subject of a cover-up! Haha!
they are called piers not pillars
There no interchange Chiltern railway to hs2 at Denham?
That is correct. I went to Denham because I wanted to look at the Colne Valley Viaduct, and that happens to be the closest station to it.
Ok
HS2 is definitely worth promoting - line we don't need, brutally cutting through cities and important environmental sites, built for no reason apart from bringing money to those involved. And brutally cut down from original plans to the point it serves no purpose (Old Oak Common end terminal, axing branches in the North etc)
Who said I was promoting it? This video is simply a construction update on the project. In any case it is worth promoting exactly because of comments like this which shows how much falsehood and misinformation surrounds the project.
The line is needed because our railways are already at capacity, and need to carry more people in future to cope with the climate crisis
The line has been designed to be very sensitive to urban and rural communities alike, and whilst some disruption is inevitable, it is FAR less than alternatives - the Lower Thames Crossing motorway affects roughly the same amount of woodland as HS2 despite being ~2% of the length of HS2 for example. The total area of ancient woodland lost to HS2 is less than 1/10,000th of the ancient woodland in this country.
I semi-agree with your last point about the cuts, but Labour (who looks increasingly likely to be the next government) have committed to the full 'Y' shape of HS2, and the idea that Euston was cut from the plans was debunked almost immediately after the news 'broke'.
What a massive waste of money this project and a stain on the countryside and wildlife in this area, it’s actually shameful of this country to build this line it’s just not needed. For the residents of ruislip and Denham and the surrounding area it’s one massive eye sore. Shame on the government.
The idea that we don't need this line comes from the misconception that it's all about speed, when in reality it's about providing much needed capacity to our increasingly strained rail network by taking express trains off existing lines, freeing them up for far more local services.
There's no doubt that any project of this scale is going to have some localised environmental impacts, but it is far smaller than comparable schemes (e.g. Lower Thames Crossing Motorway destroys more or less the same amount of woodland despite being approximately 2% of the length of HS2!) and HS2 have committed to massive rewinding projects meaning there will be a net gain in biodiversity along the route. In any case, the biggest threat to woodlands and the wildlife in this country is climate change, which this helps to address by providing an alternative to road and air travel by increasing rail capacity and driving modal shift.
@@MikeWillSee for 20 minutes saving it’s not worth it and after covid with people working online it’s proved it’s not worth it, also you might know the answer to this that the line might not get to Euston now which would be unbelievable and also to save money which it’s up to 120 billion to save 20 minutes wow there also now building the tunnels smaller which means that the trains can’t go through them so quick because of the air displacement which means that 20 minutes is lost, maybe you could clarify them points if you know. Good video btw.
@Craig Davenport first of all glad to hear you enjoyed the video!
If it's alright with you I'll try and address some of the concerns you raised, but I do have a nasty habit of writing quite a lot so I apologise in advance!
The idea that it's "just to save 20 minutes" is false for two reasons:
1. It's simply not true - the time savings between London and Birmingham are predicted to be 49 minutes!
2. The time savings are nothing but a side-benefit anyway, and the primary justification for the line has always been about capacity. I talked a little about this in my last comment but the problem with the current rail network is that intercity express trains and local stopping trains share the same line. When an Intercity train comes through it eats up loads of capacity since you have to leave a large gap in front of it so that it won't catch up with the slower trains. If you can place the express trains on their own dedicated line, it frees up the existing network for far more local, regional, and freight services. For the lines affected it allows a doubling or tripling of capacity.
The idea that we don't need extra capacity due to an increase in home-working is also a bit of a falsehood. In reality, covid has simply accelerated the trend towards home-working, which had already been taken into account when predicting future transport needs. In any case, the latest transport statistics show that we are back to 90-100% of pre-covid ridership levels, which, even if a (slight) reduction from 2019 levels, is still about the same as passenger levels were roughly 10 years ago, when the need for the line was first identified.
The idea that the line won't go to Euston is concerning, but thankfully false. The news was debunked almost as quickly as it broke, and Old Oak Common simply doesn't have the capacity to operate as a terminus. With that said, due to some poor decisions from those in government, the opening of Euston has been delayed from the original plan, meaning that it unfortunately won't open until a few years after the rest of the line.
I hear the £120bn figure being thrown around a lot, but am yet to see a reliable source for it. Until I do, I'm assuming the figure has just been made up. The cost may well increase further since it is still being calculated, but most cost increases are owing to inflation rather than mismanagement of the project. In any case, the official budget for the whole line is still £88bn, which does sound like a lot, but from my understanding, it is the cost of the _full_ project, including the Eastern branch to Leeds, rather than just the London - Birmingham section.
The other thing I think is important to note regarding cost is that it's not like they're spending £88bn a year - the cost is spread over several years if not decades, meaning the yearly budget is only about £3bn. To put that into context, approximately £8bn a year (if not more) is spent by network rail to maintain the existing network, and approximately £7bn a year is spent on subsidising domestic aviation (which is a bonkers policy decision knowing how much pollution that causes).
Not sure where you heard that news about the tunnels being made smaller, I would treat that with extreme scepticism if I were you, as many of the tunnels have already started construction, and you can't exactly change the size of a tunnel boring machines half-way through! Those that haven't started construction are due to start soon, and as such the TBMs would have already been made for them. In any case, changing any element of the design this late on would save exactly £0, since there is a huge cost to redesign something last minute, even more so if it's already begun construction!
The only way I could imagine you may have heard about the diameter of the tunnels being reduced is because some sections of the line _do_ have smaller diameter tunnels than other sections, but this has always been the case, rather than a last-minute cost-cutting measure. They may have opted for a smaller diameter tunnel if:
a) the tunnel is quite short (as is the case with the Itchington Wood tunnel)
b) the tunnel is designed for lower speeds (such as the approach into Euston)
I realise I've written quite a lot but I hope this addresses some of the concerns you raised, and if you do have any further questions I'll do my best to answer them!
@@MikeWillSee yep fair enough as I say this is what I’ve heard and I’m always ready to listen to someone else’s opinions the only one I wouldn’t agree with you is climate change but that’s another issue, I also agree with the engineering aspect of these works is fantastic let’s hope they don’t have any collapses like the one in the video, will watch your future blogs videos as I’m also interested in the rail network as such and model railways.
HS2 is an environmental disaster of epic proportions & Britain's biggest infrastructure mistake in half a century.
Thankfully, the Eastern leg & the Golborne link have now been scrapped & fingers crossed, the rest of this monstrous vanity project will never see the light of day.
If I was a cynic, I'd say you paired the two visits in a clickbaity way so people would watch thinking a HS2 tunnel had collapsed.
Hmm yeah I see what you mean, but that was very much not my intention!