427 replies to this topic

[hyposmurf]

Have to agree with Bengley... this is just plain silly. Its just opposition for the sake of opposing it. Trying to use such tenuous arguments just undermines genuine efforts to improve the final plan.

A plane might crash on Amersham and the local services might struggle to cope until reinforcements arrived. Does that mean we should shut all the airports and stop planes flying overhead ? Do you fly on your holidays putting Amersham at risk from a plane crash ?

As I replied to Bengley's post I didnt post that to oppose the proposal, just that it needs to be considered and an effective plan proposed.Closing airport's is a bit of an over reaction . I'd like to think airports arent built without a care in the world, having no emergency contingency plan.I still havent decided either way whether Im in favour or not of this proposal.

[Fran]

After reading some of the ludicrously alarmist reasons against this proposal (terrorist bombs etc), I am speechless.

Whatever one's view on the proposal in general and this route in particular, arguments surely need to be based in reality if the debate is worth having at all.

[Bengley]

As I replied to Bengley's post I didnt post that to oppose the proposal, just that it needs to be considered and an effective plan proposed.Closing airport's is a bit of an over reaction . I'd like to think airports arent built without a care in the world, having no emergency contingency plan.I still havent decided either way whether Im in favour or not of this proposal.

I understand that it needs to be thought out, but the very low likelihood of an accident or terrorist attack in a tunnel makes it non-cost effective to have a new series of emergency service stations at every tunnel along the route, considering there will be lots of tunnels, and no other main line has dedicated police for long tunnels.

[hyposmurf]

After reading some of the ludicrously alarmist reasons against this proposal (terrorist bombs etc), I am speechless.

Im neither for or against the proposed development at this stage.Its not that ludicrous.Its a possible scenario, as has been sadly demonstrated in the past.There are other possibilities that need to be considered with the proposal,such as tunnel collapse,fire,condensation problems etc that could happen inside the tunnel and need to have a contingency plan drawn up for them.Why have emergency access shafts if the developers havent considered that there maybe times that emergency access could be required?Im interested in the emergency measures and response they are proposing.How it will be implemented.Once again I am not against this proposal at this time.Unless the proposal is questioned, then we might as well not even be consulted on the proposal.

I understand that it needs to be thought out, but the very low likelihood of an accident or terrorist attack in a tunnel makes it non-cost effective to have a new series of emergency service stations at every tunnel along the route, considering there will be lots of tunnels, and no other main line has dedicated police for long tunnels.

I cant imagine that either, but it would be interesting to find out how they propose to cater for emergencies within the tunnels.

[Fran]

Im neither for or against the proposed development at this stage.Its not that ludicrous.Its a possible scenario, as has been sadly demonstrated in the past.There are other possibilities that need to be considered with the proposal,such as tunnel collapse,fire,condensation problems etc that could happen inside the tunnel and need to have a contingency plan drawn up for them.Why have emergency access shafts if the developers havent considered that there maybe times that emergency access could be required?Im interested in the emergency measures and response they are proposing.How it will be implemented.Once again I am not against this proposal at this time.Unless the proposal is questioned, then we might as well not even be consulted on the proposal.

I too am still undecided about the proposal.

However, I do think the scare stories are ludicrous. All the issues of tunnel collapse and fire etc will be part of the standard design of ANY tunnel (do you ever travel on the tube?) and whilst it could be bombed, so could anything else. I doubt it would be a high risk target. As for emergency access, that is planned every few hundred yards, with one point being near the bottom of Stanley Hill.

[hyposmurf]

I too am still undecided about the proposal.

However, I do think the scare stories are ludicrous. All the issues of tunnel collapse and fire etc will be part of the standard design of ANY tunnel (do you ever travel on the tube?) and whilst it could be bombed, so could anything else. I doubt it would be a high risk target. As for emergency access, that is planned every few hundred yards, with one point being near the bottom of Stanley Hill.

Its a worst case scenario and hopefully would never happen.Its not intended to scare people off the proposal.Im not saying that theres possibility of a terrorist bomb on the proposed line therefore it shouldnt be built, that would be daft.I'm merely asking how they intend to evacuate 1000 passengers 50 metres down in tunnel situated in a rural location,should there be an emergency?Will the emergency services wthin certain locations be given aditional training/equipment?
Take a look at Buncefield, the fire crews struggled tackling the fires. They didnt have the training required to tackle these particular fires and had to transport equipment down from the North. Eurotunnel have already had complete breakdowns from condensation and also experienced fire within the tunnels before. Even with a breakdown of a train within a tunnel, how do they intend to evacuate in that situation?
They are sensible questions that need to be asked I wouldnt like to take for granted that as a part of a standard design they have been adequately designed for.

[ianbartlett]

After reading some of the ludicrously alarmist reasons against this proposal (terrorist bombs etc), I am speechless.

Whatever one's view on the proposal in general and this route in particular, arguments surely need to be based in reality if the debate is worth having at all.

Well said Fran. Having registered on the 'Save the Chilterns etc.' Facebook group, I'm amazed at the lack of understanding about planning decisions - there's a general belief that the whole thing has been dreamt up to upset Amersham residents and without any care for the environmental impact. I'm also quite shocked at the aggressive nature of some of the comments posted there..demands to 'see my picture or F off' and an accusation that because I don't agree with the 'scrap the railway' viewpoint, I'm there simply to stir everyone up or I work for the Government. I've found it to be quite an education!

As they can't be civil to people with opposing views, I've decided to keep away from that particular group...they'll bury themselves with their own 'frothing-at-the-mouth' outrage anyway when the campaiging gets serious.

I genuinely believe this has to be built. We are at a pivotal moment in UK transport planning and trains are far and away the least environmentally damaging mode of domestic transport - say 'no' to this and we risk more motorways and bigger airports and that will definitely ruin the Chilterns.

[hyposmurf]

We are at a pivotal moment in UK transport planning and trains are far and away the least environmentally damaging mode of domestic transport - say 'no' to this and we risk more motorways and bigger airports and that will definitely ruin the Chilterns.

Yes thats true

[PaulEden]

As they can't be civil to people with opposing views, I've decided to keep away from that particular group...they'll bury themselves with their own 'frothing-at-the-mouth' outrage anyway when the campaiging gets serious.

Indeed. As internet nutters go, this lot are pretty extreme!

I genuinely believe this has to be built. We are at a pivotal moment in UK transport planning and trains are far and away the least environmentally damaging mode of domestic transport - say 'no' to this and we risk more motorways and bigger airports and that will definitely ruin the Chilterns.

Absolutely right.

[Zoom]

having no emergency contingency plan.

Of course they'll have an emergency contingency plan... unless you have evidence that they aren't ? Do you ? If not then it's just silly scare-mongering.

Im interested in the emergency measures and response they are proposing

You're getting ahead of yourself... at this stage they are proposing a route.... the consultation is about the proposed route... not about its operational and management plans.

There are many tunnels in Britain, including some of similar length such as the Severn tunnel which was built between 1873 and 1886 and has carried inter-city traffic between England and Wales for over a hundred years (for more info see http://en.wikipedia....i/Severn_Tunnel) !! There are also longer tunnels on the HS1 line through East London and under the Thames.

All tunnels are subject to engineering regulations, security, health and safety rules, inspection, and control over which there is no choice... these are requirements which the tunnel has to meet. That's it, end of story.... that's why the public won't be consulted on that.

Or do you think the public should be consulted about what materials the tunnel should be made of, how thick the walls should be ? how many emergency access shafts there should be ? how thick the fire proofing materials should be ? what fire supression system should be installed ? what surveillance system should be installed, how it should be secured against sabateurs ?

If you're really interested you might want to look at this...
http://www.hs1-staging.co.uk/NSRA0609/Network%20Statement/HS1%20Network%20Statement%20-%20June%202009.pdf

This is the HS1 network statement.... in due course a similar network statement will be developed for HS2.

[hyposmurf]

You're getting ahead of yourself... at this stage they are proposing a route.... the consultation is about the proposed route... not about its operational and management plans.

Yes its something that could be asked at a later date.

All tunnels are subject to engineering regulations, security, health and safety rules, inspection, and control over which there is no choice... these are requirements which the tunnel has to meet. That's it, end of story.... that's why the public won't be consulted on that.

Or do you think the public should be consulted about what materials the tunnel should be made of, how thick the walls should be ? how many emergency access shafts there should be ? how thick the fire proofing materials should be ? what fire supression system should be installed ? what surveillance system should be installed, how it should be secured against sabateurs ?
.

Thats stretching what I questioned a bit far, bit like closing all airports and over head flights.
I just asked how they intend to rescue up to 1000 passengers in a tunnel 50m down from a rural location.Its a logical question to ask.There have been plenty of incidents in the Eurotunnel.Some of which had 2000 passengers in five tains, sitting in the dark for a number of hours, with little information,due to some condensation.I doubt I'll be the only person to ask such a question.
I take it youre in favour of this proposal Zoom.

[hyposmurf]

Of course they'll have an emergency contingency plan... unless you have evidence that they aren't ? Do you ? If not then it's just silly scare-mongering.

In case it gets confused,that was in response to your "close all airports" suggeston, not this proposal.

[roob_the_doob]

I just asked how they intend to rescue up to 1000 passengers in a tunnel 50m down from a rural location.Its a logical question to ask.There have been plenty of incidents in the Eurotunnel.Some of which had 2000 passengers in five tains, sitting in the dark for a number of hours, with little information,due to some condensation.I doubt I'll be the only person to ask such a question.

I had presumed that this was at least part of the reason for emergency access shafts every 2.5km - train breaks down, everyone gets out and walks to the nearest tunnel and up a 50m staircase. OK maybe not everyone, just the young fit and healthy. Perhaps there will be lifts in (some of) these shafts. Or maybe everyone will just walk to the nearest tunnel entrance (less than 3 miles).

Or maybe that is why the long tunnel is twin bore, so that when one bore is blocked the emergency services can get up the other bore.

[hyposmurf]

I had presumed that this was at least part of the reason for emergency access shafts every 2.5km - train breaks down, everyone gets out and walks to the nearest tunnel and up a 50m staircase. OK maybe not everyone, just the young fit and healthy. Perhaps there will be lifts in (some of) these shafts. Or maybe everyone will just walk to the nearest tunnel entrance (less than 3 miles).

Or maybe that is why the long tunnel is twin bore, so that when one bore is blocked the emergency services can get up the other bore.

I can imagine that passengers could be evacuated via stairs that maybe in the escape access shafts, after the power is isolated.If they had a lift I guess they would also have stairs, as lifts arent that safe to travel within in the event of fire.You could be right that the twin bore could for emergency staff to use in the event of a incident.

[hyposmurf]

Just found this on the Bucks Advertiser site:

For most of this time it would be at least 30 metres under ground. But the route would be visible from above, because emergency access and egress tunnels would be built every two kilometers, with some new access roads constructed.

So does that mean these egress tunnels are specifically for exiting passengers and emergency tunnels wouldnt be used for this.Also where would these tunnels be visible from above and to what height?I cant find a height anywhere.
The papers seem to have more info then is in the proposal.Cant get Frans link to work any more.
Government consultation document
Has it moved?

[Zoom]

I doubt the emergency shafts are for passenger escape purposes... they are most likely for access by maintenance workers. I would imagine that they will have a small building at ground level. The tunnel is twin bore, presumably evacuation would be from either end or via the other tunnel.

I should point out that the Severn Tunnel is 7km long (nearly as long as the M25-Amersham tunnel would be) and it has no emergency access shafts at all because it is under the Severn Estuary. Thousands use this tunnel daily on inter-city services without thinking or worrying about the emergency plans.

It is another silly piece of scaremongering to say that the route would be visible because of a small emergency access building every 2km... that's just nuts. That's like saying that you can see the route of the sewers because there is a pumping station every 2km. The ground installations above the tunnel are NOT going to have any noticeable impact on the environment, likelihood is that once built you wouldn't even know they were there.

BTW you can access the detailed plans from the BBC web site (a little easier to navigate than the HS2 web site)...
http://news.bbc.co.u.../uk/8564154.stm

All the data is shown on the plans, for instance you can see on the plan that the tunnel is at a depth of ~40m under Chalfont St Giles, ~30m deep under Amersham... which is very deep (deeper than virtually the whole of the deepest parts of the London Undergound).

[hyposmurf]

It is another silly piece of scaremongering to say that the route would be visible because of a small emergency access building every 2km... that's just nuts. That's like saying that you can see the route of the sewers because there is a pumping station every 2km. The ground installations above the tunnel are NOT going to have any noticeable impact on the environment, likelihood is that once built you wouldn't even know they were there.

BTW you can access the detailed plans from the BBC web site (a little easier to navigate than the HS2 web site)...
http://news.bbc.co.uk/1/hi/uk/8564154.stm

All the data is shown on the plans, for instance you can see on the plan that the tunnel is at a depth of ~40m under Chalfont St Giles, ~30m deep under Amersham... which is very deep (deeper than virtually the whole of the deepest parts of the London Undergound).

Yes it could be scare mongering by the paper, but I cant find a height anywhere on that map for the emergency tunnels.I can access the maps from that site thanks,it is easier to use but I still havent been able to access the "Government consultation document" for the last couple of days, has it moved or been taken down?

[Zoom]

Yes it could be scare mongering by the paper, but I cant find a height anywhere on that map for the emergency tunnels.I can access the maps from that site thanks,it is easier to use but I still havent been able to access the "Government consultation document" for the last couple of days, has it moved or been taken down?

There isn't an emergency tunnel... its a twin bore tunnel. There are emergency access shafts (a vertical shaft) and they are marked on the map, if you scroll to the bottom you can read off how deep the tunnel is at that point... eg the one in Amersham near the bottom of Stanley Hill is 32.5m deep.... the very bottom row of black figures are the depth of the tunnel or height of the line relative to the ground level at that point.

[hyposmurf]

Sorry used wrong terminology.I looked at that to and thats why I was asking about the height of the shaft above ground.It does show a black line but its pretty hard to guess where it comes above ground level on the section view of the map,inst noted either.It possibly wont be that high or obtrusive but Im sure the residents on the London Road with it opposite their property would be interested.

[Rob]

Have been following the discussion but still haven't decided how I feel about this proposal even though I live in Old Amersham - our household is actually divided on this issue! I appreciate all the healthy debate here about various issues relating to the proposal and most people's tolerance of varying views.

Regarding the 'nasty' internet posters on the facebook site, they maybe related to some who post on local newspaper comment pages - some of them are just plain rude and very nasty and I'm sure wouldn't be game to say the same things in public with names attached.

[David P]

The new rail line will be no more of a blight on the Chilterns than the M40. In fact. the M40 is probably a lot worse - visually it is all above ground with only one cutting and acoustically it produces a continuous roar for 60 minutes an hour.
How many of the people that oppose the rail line refuse to use the M40 on principle?

[Bengley]

Sorry used wrong terminology.I looked at that to and thats why I was asking about the height of the shaft above ground.It does show a black line but its pretty hard to guess where it comes above ground level on the section view of the map,inst noted either.It possibly wont be that high or obtrusive but Im sure the residents on the London Road with it opposite their property would be interested.

If they have something to say about a structure barely larger than a medium sized garden shed, then they're just stupid.

[Zoom]

If they have something to say about a structure barely larger than a medium sized garden shed, then they're just stupid.

Yep that's about the size I was guessing for the emergency access shaft buildings would be at ground level.

David... I'm not against the line at all... I agree about the M40... I think HS2 is a good idea and should be built and it has to go somewhere.... my comments are only about how the plan could be improved.

[hyposmurf]

I know we've only been provided with the proposal at this stage, but does anyone know if there is likely to be some kind of air management in the tunnel,with air shafts,to disperse air as the train runs through the tunnel, like a piston?Would that mean there would be points where there is noise break out above the tunnels?It could be attenuated but then that would restrict the air flow and reduce the effectivenes of the wind tunnel.I could of course be talking rubbish, as Im not a tunnel expert.

[David P]

I could of course be talking rubbish, as Im not a tunnel expert.

You said it

[Bengley]

I know we've only been provided with the proposal at this stage, but does anyone know if there is likely to be some kind of air management in the tunnel,with air shafts,to disperse air as the train runs through the tunnel, like a piston?Would that mean there would be points where there is noise break out above the tunnels?It could be attenuated but then that would restrict the air flow and reduce the effectivenes of the wind tunnel.I could of course be talking rubbish, as Im not a tunnel expert.

It's a possibility, but there would be no pistons or anything, just a vent. It would either be incorporated into the access shafts or it would just be like a drain cover in the middle of a field. They might not even bother with air vents.

[roob_the_doob]

I know we've only been provided with the proposal at this stage, but does anyone know if there is likely to be some kind of air management in the tunnel,with air shafts,to disperse air as the train runs through the tunnel, like a piston?Would that mean there would be points where there is noise break out above the tunnels?It could be attenuated but then that would restrict the air flow and reduce the effectivenes of the wind tunnel.I could of course be talking rubbish, as Im not a tunnel expert.

Presumably such things are managed quite happily in longer tunnels (e.g. under the Channel) without the need to vent air.

[hyposmurf]

It's a possibility, but there would be no pistons or anything, just a vent.

Didnt actually mean pistons in the tunnel , just that it was like a piston effect.

[ianbartlett]

It's a possibility, but there would be no pistons or anything, just a vent. It would either be incorporated into the access shafts or it would just be like a drain cover in the middle of a field. They might not even bother with air vents.

Like you, I'm not a tunnel expert (a mole..?) but I don't think this sort of thing is necessary. Certainly on London Underground (which has some very long tunnels - the one from Morden to Chalk Farm on the Northern line is one continuous tunnel which includes the stations), the trains act as the air circulation system, effectively being pistons themselves. Pressure wouldn't build up as the tunnel would be open at both ends (well, hopefully..), so I can't see there'd be a need for pressure vents anywhere.

Also, keep in mind that most existing railway tunnels, which do have vents, were built in the steam era, so it was about letting the steam out.

[Zoom]

Again... I reiterate.... the Severn Railway Tunnel is >7km long (nearly as long as the proposed HS2 tunnel).... it was built in the 1880s under the Severn Estuary and is still in use today for inter-city services between England and Wales.... clearly it has no vent because it is under water.