Smart motorways are (not) more dangerous

[Fishnut]

Has anyone been able to find the report that the Guardian said should be published today? I've looked but can't find anything. PoliticsHome also says that should be published today but the Campaign for Safer Roadside Rescue and Recovery which is, I think, the organisation that should be publishing the report, has nothing but and I can't see any tweets about it.

I can't find it. I just ended up watching the Panorama episode the BBC article links to but, other than confirming you found the right organisation, it doesn't add much information.

Thanks for that

Smart motorways sound like an inherently dangerous idea to me and always have done, but I am really interested in seeing the data and how they've analysed it as feels a bit too much like a group that's made up its mind before it's done the research for my liking.

[Sciolus]

It seems to be generally accepted that Dynamic Hard Shoulder Running is sh.t and confusing (I certainly find it both), and there won't be any more of them. It's full steam ahead for All Lane Running (no hard shoulder, just occasional short refuges) though.

It's perhaps worth remembering that the function of "smart motorways", of either form, is to increase road capacity without the unfortunate need for detailed and high-profile planning inquiries which might ask difficult questions about climate impact, predict-and-provide policies and so on.

Of course, even in those terms, there is a fundamental design blunder, in that they have added the extra lane on the left, where it is invisible to drivers, instead of on the right, where they might actually use it.

[sTeamTraen]

Of course, even in those terms, there is a fundamental design blunder, in that they have added the extra lane on the left, where it is invisible to drivers, instead of on the right, where they might actually use it.

The A38(M) "Aston Expressway" in Birmingham was opened in 1972. It has 2x3 normal lanes and a 7th lane (with red tarmac) between them. The original idea was to have 4 lanes in one direction and 3 in the other during rush hours, with the direction of the middle lane depending on the time of day (i.e., with the extra lane very visible to drivers_. For (as far as I know) at least 20 years after it opened nobody dared to actually try this, as it would have meant cars driving a couple of feet from each other at a closing speed of 100mph. I think it now operates with 4 lanes one way and 2 the other, with lane 3 of the "quiet" direction being kept empty. If a truck ever jackknifes across the non-existent central reservation it's going to be a busy day at A&E.

[dyqik]

Of course, even in those terms, there is a fundamental design blunder, in that they have added the extra lane on the left, where it is invisible to drivers, instead of on the right, where they might actually use it.

The A38(M) "Aston Expressway" in Birmingham was opened in 1972. It has 2x3 normal lanes and a 7th lane (with red tarmac) between them. The original idea was to have 4 lanes in one direction and 3 in the other during rush hours, with the direction of the middle lane depending on the time of day (i.e., with the extra lane very visible to drivers_. For (as far as I know) at least 20 years after it opened nobody dared to actually try this, as it would have meant cars driving a couple of feet from each other at a closing speed of 100mph. I think it now operates with 4 lanes one way and 2 the other, with lane 3 of the "quiet" direction being kept empty. If a truck ever jackknifes across the non-existent central reservation it's going to be a busy day at A&E.

The US highways that do this do it by having a string of concrete barriers that a special equipped vehicle can move from one side of the shared lanes to the other in the middle of the day/night.

The other method is to have HOV/express lanes that are separated from the main lanes in both sides, and which are only open to toll-paying/vehicles with 2 or more passengers, and which can be closed for each direction as appropriate.

[Fishnut]

Has anyone been able to find the report that the Guardian said should be published today? I've looked but can't find anything. PoliticsHome also says that should be published today but the Campaign for Safer Roadside Rescue and Recovery which is, I think, the organisation that should be publishing the report, has nothing but and I can't see any tweets about it.

I can't find it. I just ended up watching the Panorama episode the BBC article links to but, other than confirming you found the right organisation, it doesn't add much information.

I've just tweeted the Campaign for Safer Roadside Rescue and Recovery asking about the report. I shall report back if I get a response.

[El Pollo Diablo]

I note that the quoted text in the OP appears to have disappeared from the article now?

[Fishnut]

I note that the quoted text in the OP appears to have disappeared from the article now?

That's interesting. I got a reply to my tweet and have just been emailed the report. I need to ask whether it's publicly shareable before doing anything else.

[Fishnut]

The report is shareable, they just haven't worked out how to put it on their website yet ( ) so I've uploaded it here for now. Any problems with the link, let me know as it's a file sharing site I've not used before.

I've only skimmed the report so don't have any comments yet.

[Grumble]

The report is shareable, they just haven't worked out how to put it on their website yet ( ) so I've uploaded it here for now. Any problems with the link, let me know as it's a file sharing site I've not used before.

I've only skimmed the report so don't have any comments yet.

Link didn’t work for me.

[Fishnut]

What are you using? It seems to work on firefox (I've had someone else check it)

[Martin Y]

Works for me on Edge. Thanks for posting it.

Just starting to read it now. First stat that jumps out is live lane breakdowns (where the driver is not able to get to the hard shoulder on a traditional motorway or not able get to a refuge/layby in an all lane running one). About 20% for trad motorway, about 38% for smart motorways. Not good.

[shpalman]

Thanks, works here too, chrome on linux.

[Grumble]

What are you using? It seems to work on firefox (I've had someone else check it)

Safari on my iPhone

[Bugs]

Statement today from Grant Shapps
https://www.thetimes.co.uk/edition/news ... -6w0b9grch

The stretch of the M20 and all other stretches that are currently being worked on will not be opened until we have the outcome of the stocktake.”

Is common Sense prevailing?

[Martin Y]

Somewhat exasperated that the report uses acronyms it doesn't explain.

There's a table on page 12 of "FWI rates". I'm guessing the F is for Fatal, but have no real idea. It shows rates of <whatever it is> declining over 3 years following conversion from traditional motorway to ALR smart motorway. It doesn't unpack such details as whether the figure for traditional motorway is for all motorways or specifically the stretches converted (which presumably were converted due to their high volume of traffic). Nor does it hint at any confidence intervals for the stats it provides, which might be significant if we're talking about small numbers.

But it does claim that the "FWI rate" has declined from 0.41 to 0.31 averaged across all of the All Lane Running sections and that the casualty rate has similarly declined from 16.76 to 12.08 (per hundred million vehicle miles). So it looks like Highways England data shows the smart motorways are safer. I have a suspicion that if we were able to see all of the data it might become clear that some changes (variable speed limits?) reduce accidents while others (removing hard shoulders?) do the opposite.

[El Pollo Diablo]

FWI is Fatality Weighted Injuries, we use it on the railway. It's a way of summing up the number of deaths and injuries into a single number, with (I think) 200 minor injuries and 10 serious injuries each being equal to one fatality. It's the principal measure of safety risk.

[stańczyk]

I think FWI means Fatalities and Weighted Injuries

Some information here (second paragraph)

Ninja'd by an expert

[Gentleman Jim]

Statement today from Grant Shapps
https://www.thetimes.co.uk/edition/news ... -6w0b9grch

The stretch of the M20 and all other stretches that are currently being worked on will not be opened until we have the outcome of the stocktake.”

Is common Sense prevailing?

Doesn't matter what happens with the M20 - remember, it's just a large car park if/'when customs delays cause havoc down here

[Fishnut]

Somewhat exasperated that the report uses acronyms it doesn't explain.

There's a table on page 12 of "FWI rates". I'm guessing the F is for Fatal, but have no real idea. It shows rates of <whatever it is> declining over 3 years following conversion from traditional motorway to ALR smart motorway. It doesn't unpack such details as whether the figure for traditional motorway is for all motorways or specifically the stretches converted (which presumably were converted due to their high volume of traffic). Nor does it hint at any confidence intervals for the stats it provides, which might be significant if we're talking about small numbers.

But it does claim that the "FWI rate" has declined from 0.41 to 0.31 averaged across all of the All Lane Running sections and that the casualty rate has similarly declined from 16.76 to 12.08 (per hundred million vehicle miles). So it looks like Highways England data shows the smart motorways are safer. I have a suspicion that if we were able to see all of the data it might become clear that some changes (variable speed limits?) reduce accidents while others (removing hard shoulders?) do the opposite.

I had the same complaint when skimming. Define your terms people!!

[Martin Y]

FWI is Fatality Weighted Injuries...

I think FWI means Fatalities and Weighted Injuries...

Ta. And ta.

[Sciolus]

Statement today from Grant Shapps
https://www.thetimes.co.uk/edition/news ... -6w0b9grch

The stretch of the M20 and all other stretches that are currently being worked on will not be opened until we have the outcome of the stocktake.”

Is common Sense prevailing?

Looking for a non-paywalled version of that story, I had to type "Shapps" and "smart" next to each other, possibly the first time history this has happened.

[sTeamTraen]

But it does claim that the "FWI rate" has declined from 0.41 to 0.31 averaged across all of the All Lane Running sections and that the casualty rate has similarly declined from 16.76 to 12.08 (per hundred million vehicle miles). So it looks like Highways England data shows the smart motorways are safer. I have a suspicion that if we were able to see all of the data it might become clear that some changes (variable speed limits?) reduce accidents while others (removing hard shoulders?) do the opposite.

Does it show what happened to the FWI rate on non-smart motorways over the same period? That would seem to be necessary to establish an effect.

[El Pollo Diablo]

Problem is with these things, going off actual events unfortunately isn't sufficient. Need to look at the precursors as well. Not sure if Highways have a precursor model for the motorways. But you'd think that live lane breakdowns are a pretty important precursor.

[Boustrophedon]

Looking for a non-paywalled version of that story, I had to type "Shapps" and "smart" next to each other, possibly the first time history this has happened.

Grant one-GCSE⁴-from-a-Grammar*-school Shapps.

* My Alma mater**
** I taught there too.***
*** No I didn't know Mr Shapps.
4 Woodwork.

[Martin Y]

Does it show what happened to the FWI rate on non-smart motorways over the same period? That would seem to be necessary to establish an effect.

No. The report does complain that Highways England didn't respond to their requests for a more detailed breakdown of the figures they supplied but doesn't mention figures for non-smart motorways.

It does give a table for live lane breakdowns on non-smart motorways by year, copied from here: https://www.parliament.uk/business/publ ... 1-14/3155/ It shows around 20% with no obvious trend, compared to 38% average on smart motorways.

<edit> When I followed the link to what Highways England actually submitted: https://www.parliament.uk/documents/com ... 092019.pdf it was a bit more forthcoming. In the text of the letter it says:

"These results [for 9 ALR sections operating over 1-3 years] show a 25% reduction in the FWI rate, which is a 23% improvement over the national motorway trend [and] a 28% reduction in the casualty rate, outperforming the national trend by 10%."