All Lane Running - Smart Motorways ?

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jackal
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Re: All Lane Running - Smart Motorways ?

Post by jackal »

Bryn666 wrote: Tue Jun 22, 2021 12:27
jackal wrote: Tue Jun 22, 2021 12:22
Bryn666 wrote: Tue Jun 22, 2021 11:45

I take the view that we already had a series of lines and signs in the Highway Code that apply to tidal flow roads and other forms of lane control (e.g. in tunnels), no-one would have been inherently confused by things that already existed being made more widespread. DHSR decided to ignore this existing set-up in favour of something they could write glossy brochures about instead.

Even the biggest moron on the planet can work out what a green arrow means.
As far as I know tidal flow roads either don't have merges/diverges or they handle them in the same way as a normal road does, i.e. with permanent road markings that never change their meaning. Dashed line tells you there's a merge/diverge, etc. Here are a couple of examples:

https://www.google.co.uk/maps/@52.50584 ... 384!8i8192
https://www.google.co.uk/maps/@50.40862 ... 384!8i8192

DHS do not have that luxury as, by their very nature, their merges and diverges move laterally depending on whether the hard shoulder is open. For instance the nose of the merge/diverge moves 3.5m or so to the left when a hard shoulder is open and then 3.5m back to the right when it closes. It is impossible to mark such dynamic geometry with paint. Nor is the basic binary communication of a green arrow able to communicate the necessary spatial information.

If you have an example of a tidal flow or tunnel that has a similarly dynamic merge or diverge then by all means, share it, so we can see how that would work - I genuinely do not know of any.
DHSR doesn't have the hatched/chevron area change position though - they knew immediately that it wasn't workable so that is why through junction running was trialled on the M42 after a few months; before this the M42 was just gaining a weaving lane. This set up could still be marked simply with red X, green arrows, and white move over arrows when the merge lane ends. You'd only need a hazard warning line (1004.1) in lieu of the hard shoulder line. The MS4s on DHSRs already show this in a roundabout fashion.

DHSR has diluted the meaning of solid white lines. This is where the danger has come from.
Exactly - HE's solution was to make DHS effectively into ALR at the merges and diverges. They are not dynamic at all at these points, so the paint has a fixed meaning, the nose stays where it is, etc. I think this is the best they could have done.

But I was responding to your proposal, which seemed to be that they should have kept conventional-style markings, i.e., the nose chevrons would be painted on the road in the conventional location, but when the HS was open, the nose would move 3.5m to the left (but be unmarked except by a green arrow). This seems much more dangerous in my view as it would be ambiguous what traffic is supposed to do. For instance, traffic in the (open) hard shoulder that wants to carry straight on (not exit) would have to drive OVER the solid white chevrons to continue forward, which is contrary to everything you know as a driver, and putting a green arrow over it doesn't make it any less counterintuitive and (for some drivers) panic inducing.

It seems that isn't actually what you were proposing so I guess I'm a bit stuck as to what it was. You now seem to be describing getting rid of the hard shoulder marking, which basically just makes it ALR. If so, I absolutely agree - ALR is superior to any configuration of DHS.
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Re: All Lane Running - Smart Motorways ?

Post by jackal »

Herned wrote: Tue Jun 22, 2021 12:28
jackal wrote: Tue Jun 22, 2021 12:22 If you have an example of a tidal flow or tunnel that has a similarly dynamic merge or diverge then by all means, share it, so we can see how that would work - I genuinely do not know of any.
The tidal lane through the tunnel and bridge at Saltash on the A38 uses lit catseyes to show when the lane is open or not - they show red here when the lane is closed.
Sure, it's a standard tidal flow lane indicator. But we're discussing merges/diverges within a tidal flow system, which are not (to my knowledge) dynamic. Indeed above I posted the diverge at Saltash, which is not dynamic.
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Re: All Lane Running - Smart Motorways ?

Post by Bryn666 »

jackal wrote: Tue Jun 22, 2021 12:42
Bryn666 wrote: Tue Jun 22, 2021 12:27
jackal wrote: Tue Jun 22, 2021 12:22
As far as I know tidal flow roads either don't have merges/diverges or they handle them in the same way as a normal road does, i.e. with permanent road markings that never change their meaning. Dashed line tells you there's a merge/diverge, etc. Here are a couple of examples:

https://www.google.co.uk/maps/@52.50584 ... 384!8i8192
https://www.google.co.uk/maps/@50.40862 ... 384!8i8192

DHS do not have that luxury as, by their very nature, their merges and diverges move laterally depending on whether the hard shoulder is open. For instance the nose of the merge/diverge moves 3.5m or so to the left when a hard shoulder is open and then 3.5m back to the right when it closes. It is impossible to mark such dynamic geometry with paint. Nor is the basic binary communication of a green arrow able to communicate the necessary spatial information.

If you have an example of a tidal flow or tunnel that has a similarly dynamic merge or diverge then by all means, share it, so we can see how that would work - I genuinely do not know of any.
DHSR doesn't have the hatched/chevron area change position though - they knew immediately that it wasn't workable so that is why through junction running was trialled on the M42 after a few months; before this the M42 was just gaining a weaving lane. This set up could still be marked simply with red X, green arrows, and white move over arrows when the merge lane ends. You'd only need a hazard warning line (1004.1) in lieu of the hard shoulder line. The MS4s on DHSRs already show this in a roundabout fashion.

DHSR has diluted the meaning of solid white lines. This is where the danger has come from.
Exactly - HE's solution was to make DHS effectively into ALR at the merges and diverges. They are not dynamic at all at these points, so the paint has a fixed meaning, the nose stays where it is, etc. I think this is the best they could have done.

But I was responding to your proposal, which seemed to be that they should have kept conventional-style markings, i.e., the nose chevrons would be painted on the road in the conventional location, but when the HS was open, the nose would move 3.5m to the left (but be unmarked except by a green arrow). This seems much more dangerous in my view as it would be ambiguous what traffic is supposed to do. For instance, traffic in the (open) hard shoulder that wants to carry straight on (not exit) would have to drive OVER the solid white chevrons to continue forward, which is contrary to everything you know as a driver, and putting a green arrow over it doesn't make it any less counterintuitive and (for some drivers) panic inducing.

It seems that isn't actually what you were proposing so I guess I'm a bit stuck as to what it was. You now seem to be describing getting rid of the hard shoulder marking, which basically just makes it ALR. If so, I absolutely agree - ALR is superior to any configuration of DHS.
Yes, probably not explained very well but if you want a lane you can close and open in response to traffic volume changes, you should be using conventional lane control signs and markings - not a fudge of a hard shoulder line that doesn't vibrate when you drive over it. You can't run DHSR through junctions as you point out so this works, signals tell you when to move out of the left hand lane.

It's easier to just have ALR, but the cock-ups caused by reinventing the DHSR wheel have sullied that too.
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Re: All Lane Running - Smart Motorways ?

Post by jackal »

^ Fair enough.

My short history of DHS and ALR in England would be:

1. Let's try DHS
2. Turns out the best kind of DHS is semi-ALR (i.e. ALR-style markings at merges and diverges)
3. Turns out full ALR is better than semi-ALR

It would have saved everyone a lot of trouble if they skipped straight to 3.
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Re: All Lane Running - Smart Motorways ?

Post by KeithW »

Justin Smith wrote: Tue Jun 22, 2021 12:23
KeithW wrote: Tue Jun 22, 2021 10:49
All lane running is obvious, you have 3 or more lanes all marked with dashed lines and refuges

DHSR has the hard shoulder marked with a solid line, sometimes it works like a conventional hard shoulder but other times its open to live running. The potential for confusion is obvious and they were found to be considerably LESS safe than ALR which is why they are being phased out.
Was that with a strictly enforced 50mph limit ?
Given that the photo of the M62 I appended shows the speed limit being set at 60 that would be a no. As I recall when I went through the M42 in 2008 there was a 50 showing but it was very congested at the time. The M42 is not in my opinion a good example of the motorway builders art especially the section to the M1 where it was built as D2M, of course it gets worse as they ran out of money at the end and built the last 15 miles as the All Purpose A42 - D2 and no hard shoulder.
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Re: All Lane Running - Smart Motorways ?

Post by Bryn666 »

jackal wrote: Tue Jun 22, 2021 12:57 ^ Fair enough.

My short history of DHS and ALR in England would be:

1. Let's try DHS
2. Turns out the best kind of DHS is semi-ALR (i.e. ALR-style markings at merges and diverges)
3. Turns out full ALR is better than semi-ALR

It would have saved everyone a lot of trouble if they skipped straight to 3.
Fully agree - they had already realised this with the M62 between J25 and J26 due to "you can't have DHSR through a service area, it's just silly", so why was this realisation not extended across?

I can only conclude a form of greenwash was in play - "it's not a capacity increase because we can turn it off", oh right, so it's OK as a safety decrease instead whereas if they were just honest in the first place they'd have got away with ALR from day one.
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Re: All Lane Running - Smart Motorways ?

Post by RichardA35 »

jackal wrote: Tue Jun 22, 2021 12:57 ^ Fair enough.

My short history of DHS and ALR in England would be:

1. Let's try DHS
2. Turns out the best kind of DHS is semi-ALR (i.e. ALR-style markings at merges and diverges)
3. Turns out full ALR is better than semi-ALR

It would have saved everyone a lot of trouble if they skipped straight to 3.
To be fair though when "they" embarked on 1 on the M42, 2 and 3 hadn't been thought of or trialled (or at least not in the UK) so getting past the safety cautious SSD, or whatever they were called, was going to be a long hard slog.
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Re: All Lane Running - Smart Motorways ?

Post by Big L »

M42 was originally maximum 50 if the hard shoulder is in use. Later increased to 60.
Make poetry history.

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Re: All Lane Running - Smart Motorways ?

Post by Justin Smith »

Big L wrote: Tue Jun 22, 2021 13:37 M42 was originally maximum 50 if the hard shoulder is in use. Later increased to 60.
Thanks, I thought that was the case. If there is an outcry over accidents on Smart motorways then increasing the limit seems a perverse thing to do. 50mph may be significantly slower than 70mph, but it's a lot faster than zero, which is the possible alternative traffic keep increasing and if public opinion continues to be against all lane running smart motorways. It is highly doubtful the government will be building many more motorways so squeezing more capacity out of our existing ones is probably the only game in town.
Last edited by Justin Smith on Tue Jun 22, 2021 14:08, edited 1 time in total.
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Re: All Lane Running - Smart Motorways ?

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Justin Smith wrote: Tue Jun 22, 2021 13:58
Big L wrote: Tue Jun 22, 2021 13:37 M42 was originally maximum 50 if the hard shoulder is in use. Later increased to 60.
Thanks, I thought that was the case. If there is an outcry over accidents on Smart motorways then increasing the limit seems a perverse thing to do. 50mph may be significantly slower than 70mph, but it's a lot faster than zero, which is the possible alternative if public opinion continues to be against all lane running smart motorways.
The majority of incidents people are worried over occur on ALR sections running at 70 mph - the problem is HE's supposed slow reaction times to stranded vehicles.
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Re: All Lane Running - Smart Motorways ?

Post by Justin Smith »

Bryn666 wrote: Tue Jun 22, 2021 14:05
Justin Smith wrote: Tue Jun 22, 2021 13:58
Big L wrote: Tue Jun 22, 2021 13:37 M42 was originally maximum 50 if the hard shoulder is in use. Later increased to 60.
Thanks, I thought that was the case. If there is an outcry over accidents on Smart motorways then increasing the limit seems a perverse thing to do. 50mph may be significantly slower than 70mph, but it's a lot faster than zero, which is the possible alternative if public opinion continues to be against all lane running smart motorways.
The majority of incidents people are worried over occur on ALR sections running at 70 mph - the problem is HE's supposed slow reaction times to stranded vehicles.
But the point is there wouldn't be all lane running at 70mph any more. 70mph would only be the limit if the hard shoulder was in use as a hard shoulder. Whether this is reasonable or not (the argument is that A road DCs have a 70mph limit) is not really the point, the public are against ALR at 70mph on motorways.
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Re: All Lane Running - Smart Motorways ?

Post by Bryn666 »

Justin Smith wrote: Tue Jun 22, 2021 14:11
Bryn666 wrote: Tue Jun 22, 2021 14:05
Justin Smith wrote: Tue Jun 22, 2021 13:58

Thanks, I thought that was the case. If there is an outcry over accidents on Smart motorways then increasing the limit seems a perverse thing to do. 50mph may be significantly slower than 70mph, but it's a lot faster than zero, which is the possible alternative if public opinion continues to be against all lane running smart motorways.
The majority of incidents people are worried over occur on ALR sections running at 70 mph - the problem is HE's supposed slow reaction times to stranded vehicles.
But the point is there wouldn't be all lane running at 70mph any more. 70mph would only be the limit if the hard shoulder was in use as a hard shoulder. Whether this is reasonable or not (the argument is that A road DCs have a 70mph limit) is not really the point, the public are against ALR at 70mph on motorways.
With due respect that isn't the case, the public are more likely to find themselves against 100+ miles of 50 mph on the M6 when it becomes heavily enforced and the fines rack up. The very real safety problems of ALR are not resolved by speed limit tinkering, it requires better response times and more resourcing to patrol motorways pending the invention of this all singing all dancing stopped vehicle detection that doesn't exist yet.
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Re: All Lane Running - Smart Motorways ?

Post by jervi »

Justin Smith wrote: Tue Jun 22, 2021 14:11
Bryn666 wrote: Tue Jun 22, 2021 14:05
Justin Smith wrote: Tue Jun 22, 2021 13:58

Thanks, I thought that was the case. If there is an outcry over accidents on Smart motorways then increasing the limit seems a perverse thing to do. 50mph may be significantly slower than 70mph, but it's a lot faster than zero, which is the possible alternative if public opinion continues to be against all lane running smart motorways.
The majority of incidents people are worried over occur on ALR sections running at 70 mph - the problem is HE's supposed slow reaction times to stranded vehicles.
But the point is there wouldn't be all lane running at 70mph any more. 70mph would only be the limit if the hard shoulder was in use as a hard shoulder. Whether this is reasonable or not (the argument is that A road DCs have a 70mph limit) is not really the point, the public are against ALR at 70mph on motorways.
Some people suggest lower speed limits to mitigate no hard shoulder, however... most normal people are just fine with 70, if not suggesting faster speeds of 80 or 90 mph during off-peak times.
And that all sorts of dual carriageways run at 70mph with at-grade junctions, poor alignment, lack of refuge or parking areas and congested with no safety issues crying out for a lower speed limit.
Take the A1 through Lincolnshire for example, no one is demanding that to have a lower speed limit.
Or what about the A23 at Handcross hill with barriers either side of the carriageway with no place to pull over in an event of a breakdown, which is 2 miles long and mostly uphill on a D3, I don't see anyone suggesting that has a lower limit.
The fact that a D2 or D3 with lack of any active safety features can run at 70mph without a hitch does prove that a D4ALR can work at 70mph, especially once you put tons of mitigation technology in place. Drivers are the issue, not the road.
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Re: All Lane Running - Smart Motorways ?

Post by JRN »

Bryn666 wrote: Tue Jun 22, 2021 12:27
jackal wrote: Tue Jun 22, 2021 12:22
Bryn666 wrote: Tue Jun 22, 2021 11:45

I take the view that we already had a series of lines and signs in the Highway Code that apply to tidal flow roads and other forms of lane control (e.g. in tunnels), no-one would have been inherently confused by things that already existed being made more widespread. DHSR decided to ignore this existing set-up in favour of something they could write glossy brochures about instead.

Even the biggest moron on the planet can work out what a green arrow means.
As far as I know tidal flow roads either don't have merges/diverges or they handle them in the same way as a normal road does, i.e. with permanent road markings that never change their meaning. Dashed line tells you there's a merge/diverge, etc. Here are a couple of examples:

https://www.google.co.uk/maps/@52.50584 ... 384!8i8192
https://www.google.co.uk/maps/@50.40862 ... 384!8i8192

DHS do not have that luxury as, by their very nature, their merges and diverges move laterally depending on whether the hard shoulder is open. For instance the nose of the merge/diverge moves 3.5m or so to the left when a hard shoulder is open and then 3.5m back to the right when it closes. It is impossible to mark such dynamic geometry with paint. Nor is the basic binary communication of a green arrow able to communicate the necessary spatial information.

If you have an example of a tidal flow or tunnel that has a similarly dynamic merge or diverge then by all means, share it, so we can see how that would work - I genuinely do not know of any.
DHSR doesn't have the hatched/chevron area change position though - they knew immediately that it wasn't workable so that is why through junction running was trialled on the M42 after a few months; before this the M42 was just gaining a weaving lane. This set up could still be marked simply with red X, green arrows, and white move over arrows when the merge lane ends. You'd only need a hazard warning line (1004.1) in lieu of the hard shoulder line. The MS4s on DHSRs already show this in a roundabout fashion.

DHSR has diluted the meaning of solid white lines. This is where the danger has come from.
I believe they actually tried more than 1 way of implementing through junction running on DHSR smart motorways.
For instance the M1 (J10-13) scheme features through junction running at every intermediate junction, and uses ALR style markings:
https://www.google.co.uk/maps/@51.88884 ... 6656?hl=en
The motorway "opens" to ALR before the junction, then in effect "closes" back to DHSR after it.

Whereas the M6 junction 5 westbound has a layout where the diverge at the hard shoulder / left running lane is marked with a solid white line but no chevrons (on the leading part of it), so that it can be either driven over or not, depending on how the signs are set:
https://www.google.co.uk/maps/@52.50923 ... 6656?hl=en
I think this layout is especially hard for drivers to comprehend.
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Re: All Lane Running - Smart Motorways ?

Post by Justin Smith »

Bryn666 wrote: Tue Jun 22, 2021 14:22
Justin Smith wrote: Tue Jun 22, 2021 14:11
Bryn666 wrote: Tue Jun 22, 2021 14:05

The majority of incidents people are worried over occur on ALR sections running at 70 mph - the problem is HE's supposed slow reaction times to stranded vehicles.
But the point is there wouldn't be all lane running at 70mph any more. 70mph would only be the limit if the hard shoulder was in use as a hard shoulder. Whether this is reasonable or not (the argument is that A road DCs have a 70mph limit) is not really the point, the public are against ALR at 70mph on motorways.
With due respect that isn't the case, the public are more likely to find themselves against 100+ miles of 50 mph on the M6 when it becomes heavily enforced and the fines rack up. The very real safety problems of ALR are not resolved by speed limit tinkering, it requires better response times and more resourcing to patrol motorways pending the invention of this all singing all dancing stopped vehicle detection that doesn't exist yet.
The direction of travel for Smart motorways, public opinion wise, is they will be abolished. Thus the choice is not between doing 70mph or 50mph all the way from B/ham to Manchester, it will be doing 30mph (average speed) unless something significant happens.
We drove up from Reading to Sheff a few weeks ago and the traffic was the worst I have ever known, possibly due to hardly anyone on public transport and everyone taking holidays in the UK. We ended up going via Burton and onto the A38, it took over 5 hours (nett)..... Forget 70mph, I would have been delighted to have been able to do that journey at 50mph !

It does not matter what technology exists, if you break down they cannot immediately stop the traffic behind you, it is impossible. That is why people want the reassurance of seeing a hard shoulder to the left of them. They might not be quite so worried if there was a 50mph limit in force, but I cannot see any other way of reassuring them.
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Re: All Lane Running - Smart Motorways ?

Post by KeithW »

jervi wrote: Tue Jun 22, 2021 16:43
Some people suggest lower speed limits to mitigate no hard shoulder, however... most normal people are just fine with 70, if not suggesting faster speeds of 80 or 90 mph during off-peak times.
And that all sorts of dual carriageways run at 70mph with at-grade junctions, poor alignment, lack of refuge or parking areas and congested with no safety issues crying out for a lower speed limit.
Take the A1 through Lincolnshire for example, no one is demanding that to have a lower speed limit.
Well now lower speed limits was considered through the Pontons, instead they installed average speed cameras and there are of course sections of the A1 with lower speed limits, Elkesley, Buckden, Southoe and Sandy all come to mind.
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Re: All Lane Running - Smart Motorways ?

Post by Chris5156 »

Justin Smith wrote: Tue Jun 22, 2021 14:11Whether this is reasonable or not (the argument is that A road DCs have a 70mph limit) is not really the point, the public are against ALR at 70mph on motorways.
As someone who drives the ALR section of the M3 in the rush hour most days, I have to say that there’s a gulf here. On the one hand I see the campaigns that say Smart Motorways are dangerous, and that “the public” don’t feel safe on a motorway running at 70mph without a hard shoulder. And on the other hand I have my extensive experience of the M3 daily, and frequent journeys on the M25 and M1 ALR sections, where all around me everybody is driving at 70mph and above on a motorway without a hard shoulder.

If there really is a groundswell of public fear about these roads, why is nobody driving on them at the reduced speed they feel to be safe? Shouldn’t we be seeing platoons of people dead set against Smart Motorways trundling up the M3 at a steady 50? After all, a good driver drives at the speed they judge to be safe.

I realise that there’s a lot more at play in the speed at which people choose to drive, but it’s hard not to conclude that virtually everyone who actually drives on these roads feels safe driving them at 70. As with many things a vocal publicity campaign shouldn’t be mistaken for widespread support. It might be. But it might equally just be a very well organised and effective campaign.
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Re: All Lane Running - Smart Motorways ?

Post by Bryn666 »

JRN wrote: Tue Jun 22, 2021 16:48
Bryn666 wrote: Tue Jun 22, 2021 12:27
jackal wrote: Tue Jun 22, 2021 12:22
As far as I know tidal flow roads either don't have merges/diverges or they handle them in the same way as a normal road does, i.e. with permanent road markings that never change their meaning. Dashed line tells you there's a merge/diverge, etc. Here are a couple of examples:

https://www.google.co.uk/maps/@52.50584 ... 384!8i8192
https://www.google.co.uk/maps/@50.40862 ... 384!8i8192

DHS do not have that luxury as, by their very nature, their merges and diverges move laterally depending on whether the hard shoulder is open. For instance the nose of the merge/diverge moves 3.5m or so to the left when a hard shoulder is open and then 3.5m back to the right when it closes. It is impossible to mark such dynamic geometry with paint. Nor is the basic binary communication of a green arrow able to communicate the necessary spatial information.

If you have an example of a tidal flow or tunnel that has a similarly dynamic merge or diverge then by all means, share it, so we can see how that would work - I genuinely do not know of any.
DHSR doesn't have the hatched/chevron area change position though - they knew immediately that it wasn't workable so that is why through junction running was trialled on the M42 after a few months; before this the M42 was just gaining a weaving lane. This set up could still be marked simply with red X, green arrows, and white move over arrows when the merge lane ends. You'd only need a hazard warning line (1004.1) in lieu of the hard shoulder line. The MS4s on DHSRs already show this in a roundabout fashion.

DHSR has diluted the meaning of solid white lines. This is where the danger has come from.
I believe they actually tried more than 1 way of implementing through junction running on DHSR smart motorways.
For instance the M1 (J10-13) scheme features through junction running at every intermediate junction, and uses ALR style markings:
https://www.google.co.uk/maps/@51.88884 ... 6656?hl=en
The motorway "opens" to ALR before the junction, then in effect "closes" back to DHSR after it.

Whereas the M6 junction 5 westbound has a layout where the diverge at the hard shoulder / left running lane is marked with a solid white line but no chevrons (on the leading part of it), so that it can be either driven over or not, depending on how the signs are set:
https://www.google.co.uk/maps/@52.50923 ... 6656?hl=en
I think this layout is especially hard for drivers to comprehend.
That M6 J5 example is abysmal - they presumably would argue they can't do through junction running because of the lack of entry slips beyond but that's easily solved by just having the space beyond as a merge area back in. Scottish lane drops used to be designed like this.
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Re: All Lane Running - Smart Motorways ?

Post by jackal »

Chris5156 wrote: Tue Jun 22, 2021 18:33As with many things a vocal publicity campaign shouldn’t be mistaken for widespread support. It might be. But it might equally just be a very well organised and effective campaign.
The main thing is they have several national newspapers and, seemingly, the national broadcaster behind them. Any cause could be given the appearance of a 'groundswell' with that kind of support.
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Justin Smith
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Re: All Lane Running - Smart Motorways ?

Post by Justin Smith »

Chris5156 wrote: Tue Jun 22, 2021 18:33
Justin Smith wrote: Tue Jun 22, 2021 14:11Whether this is reasonable or not (the argument is that A road DCs have a 70mph limit) is not really the point, the public are against ALR at 70mph on motorways.
As someone who drives the ALR section of the M3 in the rush hour most days, I have to say that there’s a gulf here. On the one hand I see the campaigns that say Smart Motorways are dangerous, and that “the public” don’t feel safe on a motorway running at 70mph without a hard shoulder. And on the other hand I have my extensive experience of the M3 daily, and frequent journeys on the M25 and M1 ALR sections, where all around me everybody is driving at 70mph and above on a motorway without a hard shoulder.

If there really is a groundswell of public fear about these roads, why is nobody driving on them at the reduced speed they feel to be safe? Shouldn’t we be seeing platoons of people dead set against Smart Motorways trundling up the M3 at a steady 50? After all, a good driver drives at the speed they judge to be safe.

I realise that there’s a lot more at play in the speed at which people choose to drive, but it’s hard not to conclude that virtually everyone who actually drives on these roads feels safe driving them at 70. As with many things a vocal publicity campaign shouldn’t be mistaken for widespread support. It might be. But it might equally just be a very well organised and effective campaign.
It's not about what speed people drive at, it's about the worry they have (quite legitimately in my view) what will happen if they breakdown and someone hits them, so the fact people drive at 70 on a motorway with ALR is no indication as to whether they're happy about the fact there is no hard shoulder. They think, and rationally they must be right, that if they broke down and the other traffic was doing 50 rather than 70 there would be a lower chance they'd get hit and if they did there would be less chance they'd get killed. The only slight problem is a 50 limit would not slow the trucks down much, have people ever noticed that when 50 av speed cameras are in use the trucks are going faster then most cars, I have always assumed it's because their speedos are more accurate ? But if a truck hits you it will do you far more damage than even a car.
Bear in mind that however perfect the monitoring it would take minutes for the traffic to slow down.
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