Smart Motorways, is it time to end them?

[Peter Sarf]

You are definitely right with the technology not quite being there. Our new car (new model that came out last year) can pick up road signs, but thankfully requires you to press a button to set the cruise to that speed. I was going down a National speed country lane recently, and there were some road works on a farm access road adjacent with a 5 mph speed sign, which my car picked up. Very thankful it didn’t just slam on!

Ours also has “lane assist”, but someone had the grand idea of having it active at all speeds. So trying to overtake parked cars on a 30 road can be quite suicidal when it tries to turn you back into them… Then it has the audacity to tell you to brake as you are about to crash!

I had a VW Golf rental car with lane assist which I didnt know it had. Driving along a dual carriageway and overtaking something provided a weird sensation that I was going over some kind of camber or high spot where the lane lines were. Eventually worked out it was lane assist thanks to the rude messages about keep in lane or hold the steering wheel (or something like that) that appeared on the dash. So what was happening was as I was about to cross the lane lines the car tried to steer back into lane hence the weird sensation. Provided you held the steering wheel fairly tightly you just got the weird rolling sensation but if held lightly it was very disconcerting as it tried to pull you back and towards the car you were passing. No crash detection fortunately otherwise the brakes would presumably come on as it pulled back towards the car I was passing.

My mothers car had this lane assist. She asked me to drive it as she was so nervous. I spent a while trying to figure out where the noises were coming from and then why. VERY DISTRACTING.

Does that mean you were overtaking something without indicating? The description on VW's website implies lane assist only kicks in when you're crossing lines and the indicators aren't on.

I wonder if the indicators were being used. I tend to use the indicators a lot but I recall it got challenging where I wanted the left divergence of one lane. I was not indicating because there was also a left turn just before with someone waiting to come out of it !. At that point I had just realised what was happening. We then crossed some worn out markings from some old road works that were not really any more worn than the correct road markings. No one was near so I indicated to overcome the cars panic. That gave me the proof I needed that some intelligence was competing with me.

My new(ish) car has slightly intelligent indicators that cancel on me quite often. For instance when going round a stationary bus - really annoys me when I want to indicate. So I keep one hand holding the indicator stalk left or right if I can. Or other times I cancel them only to turn them the opposite way. I cannot detect whether the indicators are on by feel as the stalk always stays central. So I have to look down at the dashboard. This gets bad when I can hear the clicking but have to look at the dash to see if the car is indicating left or right before trying to cancel. Worse still the two arrows are on opposite sides of all the guages so it takes a longer look. I am now regularly dropping my eyes to check the indicators. Another distraction.

I have been thinking a quick swerve might be a batter way of cancelling the indicators !.

These features, like smart motorways, feel to me like too much complication leading to distraction and confusion.

 

[Jamesrob637]

The M6 J15-J13 was still 60 southbound by the overhead gantries a fortnight ago but all four lanes are now in operation. Northbound it's still only 3 lanes however things look just about to open all four. Again, the speed was 60.

 

[swt_passenger]

The M6 J15-J13 was still 60 southbound by the overhead gantries a fortnight ago but all four lanes are now in operation. Northbound it's still only 3 lanes however things look just about to open all four. Again, the speed was 60.

The M27 Southampton to Fareham is running with 4 lanes fully open for the last month or so, but the gantries appear stuck on 60 whenever I use it. I wonder if this is now a permanent feature?

 

[LSWR Cavalier]

Apparently 'smart' motorways are quite safe. Not surprising, they are so hazardous that one takes even more care than usual, or avoids them altogether if possible.

 

[Bletchleyite]

Apparently 'smart' motorways are quite safe. Not surprising, they are so hazardous that one takes even more care than usual, or avoids them altogether if possible.

They are basically the same as a dual carriageway A-road. These are less safe than motorways, but people don't actively avoid them.

 

[Jamesrob637]

The M27 Southampton to Fareham is running with 4 lanes fully open for the last month or so, but the gantries appear stuck on 60 whenever I use it. I wonder if this is now a permanent feature?

I'd say not because J19-J16 of the M6 is national speed limit (although those works were completed pre-COVID: 2019 I believe).

 

[gg1]

I had a VW Golf rental car with lane assist which I didnt know it had. Driving along a dual carriageway and overtaking something provided a weird sensation that I was going over some kind of camber or high spot where the lane lines were. Eventually worked out it was lane assist thanks to the rude messages about keep in lane or hold the steering wheel (or something like that) that appeared on the dash. So what was happening was as I was about to cross the lane lines the car tried to steer back into lane hence the weird sensation. Provided you held the steering wheel fairly tightly you just got the weird rolling sensation but if held lightly it was very disconcerting as it tried to pull you back and towards the car you were passing. No crash detection fortunately otherwise the brakes would presumably come on as it pulled back towards the car I was passing.

My Kia Niro has lane assist too, when overtaking it's not a problem as indicating disables it but there is one specific circumstance when it's downright dangerous.

When driving along a relatively narrow 2 lane road with white lines painted along the edge, it tries to nudge you back towards the centre of the road if you get too close to the edge, directly into the path of the oncoming vehicle you've just moved over to pass. It can at least be turned off by a button on the dashboard (though annoyingly you have to do it every time you start the car), I believe that on some cars you have to go into the settings menus to deactivate it.

 

[Starmill]

They are basically the same as a dual carriageway A-road. These are less safe than motorways, but people don't actively avoid them.

As people keep saying, the risks involved on a new "smart" motorway are actually lower than on a typical grade separated modern dual carriageway (sometimes known as an expressway), because the former must have the new generation of variable message signs and CCTV with the radar equipment and stopped vehicle detection.

 

[LSWR Cavalier]

What about getting vehicle and/or people off the road if the vehicle breaks down? On a smart motorway the barriers often prevent this, people may or may not be able to climb over them.

On an old dual-carriageway people and vehicle can often get onto the grass verge.

 

[deep south]

I drove down the M1 earlier this week, and on a long 4 lane stretch of smart motorway there was a section with a 50 limit and the overhead signs said "reports of lane closure".

I thought that there was complete CCTV coverage as part of the smart bit, so why didn't the control room staff simply look at their monitors to see what was going on? Or send one of the highways agency patrols...?

And there wasn't a blockage to be seen.

 

[Lampshade]

The M27 Southampton to Fareham is running with 4 lanes fully open for the last month or so, but the gantries appear stuck on 60 whenever I use it. I wonder if this is now a permanent feature?

I drove down there a couple of weeks ago at 4am and they were all set to 60.

 

[Bletchleyite]

I drove down there a couple of weeks ago at 4am and they were all set to 60.

Parts of the M6 have semi-permanent 60s due to breaches of air quality regulations in those areas, e.g. up near Wednesbury. It says why on the displays, though.

 

[swt_passenger]

I drove down there a couple of weeks ago at 4am and they were all set to 60.

Yes, however I’ve since looked at the Highways website and they mention at least a month of testing within a 60 limit, I think it’ll be most of this month.

 

[domcoop7]

Since the "pause" to new Smart Motorways was announced, it was decided that existing schemes can carry on, new ones won't be planned, but schemes in progress can't open until they have radar detectors to identify stopped vehicles.

So what they've done on, e.g. the M6 around Staffordshire, is open all four lanes of the road, but still declare it as under roadworks and not completed (pending the radar being installed). Because it isn't completed and it's a roadwork zone, they put a temporary 60MPH limit.

Whereas, the M62 from Croft to Eccles, which was completed a few months earlier, but still also needed the radar detectors (which are being installed), is not under roadworks, and is open at 70MPH. Even though in both cases the actual work is going on at night and there's literally no difference between the two sections of road other than one finished a few months earlier than the other one!

 

[warwickshire]

Yes they should. M6 Junction 6 to Junction 7 has 60 due to air pollution restrictions strange but true. However M42 between Junction 3A and Junction 7 when speed restriction 40 comes on for no apparent reason. Causes constant accidents.
Especially around Junction 5 at Solihull for example . Ie on one gantry only causes havoc due to cars suddenly having to slow down and heavy delays resulting in behind due to serious accidents occurring due to above location and cars ramming into each other.

 

[camerar1]

The M27 Southampton to Fareham is running with 4 lanes fully open for the last month or so, but the gantries appear stuck on 60 whenever I use it. I wonder if this is now a permanent feature?

I hear that the M27 is stuck at 60 for lack of a safety approval. I drive the full length once or twice a week.

 

[Bletchleyite]

Permanent 60 might not be a bad plan, will improve safety and reduce fuel consumption.

 

[PeterY]

Permanent 60 might not be a bad plan, will improve safety and reduce fuel consumption.

I agree with you. The harsh reality is 60 MPH will the minimum speed. Drivers mostly drive over the speed limit.

 

[zwk500]

Permanent 60 might not be a bad plan, will improve safety and reduce fuel consumption.

It will only improve safety if drivers leave the correct gap. My experience is that under restrictions drivers tend to close up from what was already and unsafe distance to one that requires a professional racing reaction time and setup.

 

[DelW]

The M1 between junctions 13 and 14 has been converted to all lane running with four lanes, completed a few weeks ago, but every time I've used it the overhead speed limit signs have been set at 60. There are signs on the verges saying something like "speed limit set for system test", but I wonder if it will actually be a permanent feature because of the safety concerns regarding all lane running?

Answering my earlier question, on my last couple of journeys, M1 J13 to J14 has been running using all four lanes at 70mph (when clear enough) with no signage on the gantries.

 

[maniacmartin]

I hate smart motorways and don't feel safe on them. Given many drivers ignore the dynamic speed limits, it can feel like you're going to be rear ended if you slow to the sometimes stupidly slow limits. There's also the problem of getting trapped in a "fast" lane doing bang on the limit after a limit reduction, with everyone undertaking and not letting you move into lanes to the left despite indicating. When there is a speed limit enforced by cameras on a motorway or other high quality dual carriageway, it sometimes encourages traffic in multiple lanes to be driving at very similar speeds and do lots of slow undertakes, spending lots of time in your left mirror blind spot. These issues seem to happen all the time to me on the southern M25.

I've also noticed that the operators leave restrictions in place long after the obstruction or congestion has cleared, and reduce speeds for miles in advance of any obstruction, which leads to people not taking the limits seriously when they are actually needed.

 

[zwk500]

I hate smart motorways and don't feel safe on them. Given many drivers ignore the dynamic speed limits, it can feel like you're going to be rear ended if you slow to the sometimes stupidly slow limits. There's also the problem of getting trapped in a "fast" lane doing bang on the limit after a limit reduction, with everyone undertaking and not letting you move into lanes to the left despite indicating. When there is a speed limit enforced by cameras on a motorway or other high quality dual carriageway, it sometimes encourages traffic in multiple lanes to be driving at very similar speeds and do lots of slow undertakes, spending lots of time in your left mirror blind spot. These issues seem to happen all the time to me on the southern M25.

I agree with all of this, I've had many similar experiences when driving M1-M25-M23 quite regularly.

I've also noticed that the operators leave restrictions in place long after the obstruction or congestion has cleared, and reduce speeds for miles in advance of any obstruction, which leads to people not taking the limits seriously when they are actually needed.

The limits are designed to be set miles in advance so that people take longer to get to the point of obstruction. This gives people clearing up the accident more time to try and clear it (or at least reopen a bit more road), and gives the traffic a better chance of sifting itself into the open lanes when the arrows and red Xs start appearing. As you say, this theory is ruined by a) a fair amount of false alarms and b) people being too self-important and ignoring the limits.

 

[Starmill]

I hate smart motorways and don't feel safe on them. Given many drivers ignore the dynamic speed limits, it can feel like you're going to be rear ended if you slow to the sometimes stupidly slow limits. There's also the problem of getting trapped in a "fast" lane doing bang on the limit after a limit reduction, with everyone undertaking and not letting you move into lanes to the left despite indicating. When there is a speed limit enforced by cameras on a motorway or other high quality dual carriageway, it sometimes encourages traffic in multiple lanes to be driving at very similar speeds and do lots of slow undertakes, spending lots of time in your left mirror blind spot. These issues seem to happen all the time to me on the southern M25.

I've also noticed that the operators leave restrictions in place long after the obstruction or congestion has cleared, and reduce speeds for miles in advance of any obstruction, which leads to people not taking the limits seriously when they are actually needed.

While I quite agree with the point and I've witnessed similar issues myself, it also strikes me that the root cause of these problems is actually other people's bad driving, and not the dynamic traffic management itself. Obviously that's not much consolation to you, or to anyone trying to mitigate risk arising from the irresponsible driving of others.

 

[AM9]

I hate smart motorways and don't feel safe on them. Given many drivers ignore the dynamic speed limits, it can feel like you're going to be rear ended if you slow to the sometimes stupidly slow limits. There's also the problem of getting trapped in a "fast" lane doing bang on the limit after a limit reduction, with everyone undertaking and not letting you move into lanes to the left despite indicating. When there is a speed limit enforced by cameras on a motorway or other high quality dual carriageway, it sometimes encourages traffic in multiple lanes to be driving at very similar speeds and do lots of slow undertakes, spending lots of time in your left mirror blind spot. These issues seem to happen all the time to me on the southern M25.

I've also noticed that the operators leave restrictions in place long after the obstruction or congestion has cleared, and reduce speeds for miles in advance of any obstruction, which leads to people not taking the limits seriously when they are actually needed.

There's a slight irony in your comment: "Given many drivers ignore the dynamic speed limits, it can feel like you're going to be rear ended if you slow to the sometimes stupidly slow limits." Either

the limits are appropriate, but drivers don't have enough information to make a valid judgement - a common cause of many traffic incidents​

or​

they are inappropriate but drivers think therefore they don't apply to them - an equally common cause of traffic incidents​

I don't like smart motorways primarily because they trade established safety measures for appeasing impatient drivers. One can only hope that the future switch to non-polluting vehicles (EVs) will blow away the specious argument that traffic queues cause more carbon/pollution than roads with most vehicles travelling at (or even exceeding) the 70mph speed limit. In reality vehicles need more energy to overcome aerodynamic losses at high speed than when stationary or at low speeds, so a slow-moving queue of EVs uses less energy per mile energy which means this desperate urge to travel faster gains nothing but creates many safety and environmental issues.

 

[PeterC]

There's a slight irony in your comment: "Given many drivers ignore the dynamic speed limits, it can feel like you're going to be rear ended if you slow to the sometimes stupidly slow limits." Either

the limits are appropriate, but drivers don't have enough information to make a valid judgement - a common cause of many traffic incidents​

or​

they are inappropriate but drivers think therefore they don't apply to them - an equally common cause of traffic incidents​

I don't like smart motorways primarily because they trade established safety measures for appeasing impatient drivers. One can only hope that the future switch to non-polluting vehicles (EVs) will blow away the specious argument that traffic queues cause more carbon/pollution than roads with most vehicles travelling at (or even exceeding) the 70mph speed limit. In reality vehicles need more energy to overcome aerodynamic losses at high speed than when stationary or at low speeds, so a slow-moving queue of EVs uses less energy per mile energy which means this desperate urge to travel faster gains nothing but creates many safety and environmental issues.

I agree about aerodynamic resistance. I get my best petrol consumption on a busy but steadily moving M25 with a pretty solid 50 limit.

 

[AM9]

I agree about aerodynamic resistance. I get my best petrol consumption on a busy but steadily moving M25 with a pretty solid 50 limit.

If you are getting lower consumption that means lower CO2, lower pollution and less chance of traffic incidents.

... and EVs observing lower speed limits do even better by virtue of range extension meaning that they need to recharge less often.

 

[skyhigh]

Had an interesting experience on Saturday on the M1. With no previous warning, the limit on lane 1 (next to the hardshoulder) went straight to 20MPH, with the limit on all other lanes showing as 40MPH. I didn't think it was permitted to have differing speed limits on different lanes of the same section - I also wasn't aware that the limit could be as low as 20MPH! I'm presuming it was an error rather than intentional?

 

[Nova1]

I also wasn't aware that the limit could be as low as 20MPH! I'm presuming it was an error rather than intentional?

from https://assets.publishing.service.g.../1008823/Variable_Signs_and_Signal_Policy.pdf

 

[Snow1964]

The section of M4 between M32 and M5 junctions had one of these cheap widenings with smart motorway.

When hard shoulder is open there are no speed restrictions, but they always seem to have a 60mph limit on all lanes when the hard shoulder is open.

There are some gantries beyond where the dashed white lines start (as opposed to lane divider white lines), so lanes are separate for each motorway, but they always show same restrictions on all lanes even if one route is virtually deserted. It is only next sign well beyond the diverging junction that shows all clear

 

[ABB125]

The section of M4 between M32 and M5 junctions had one of these cheap widenings with smart motorway.

When hard shoulder is open there are no speed restrictions, but they always seem to have a 60mph limit on all lanes when the hard shoulder is open.

There are some gantries beyond where the dashed white lines start (as opposed to lane divider white lines), so lanes are separate for each motorway, but they always show same restrictions on all lanes even if one route is virtually deserted. It is only next sign well beyond the diverging junction that shows all clear

That's because that bit is dynamic hard shoulder (ie: the worst of both worlds). The hard shoulder can only be used as a running lane if the speed limit is 60mph or less.

I believe that the "Bristol area" (locations unspecified) is planned to be upgraded at some point by National Highways. What this will involve is currently unknown. And given National Highways' record, it won't work anyway!