Wales becomes Trumpton

[Brigadier]

We are discussing the 20mph limits in Wales.

So, you consider the Welsh 20 limit still to be too high?

 

[carmanmemoranda]

So, you consider the Welsh 20 limit still to be too high?

Strawman

 

[Brigadier]

read what mbk has claimed

As I don't claim that he said anything of the sort, I won't be going back to dig out anything.
The burden is on you.

 

[Brigadier]

Strawman

It is a question.

 

[carmanmemoranda]

As I don't claim that he said anything of the sort, I won't be going back to dig out anything.
The burden is on you.

Well we stand where we stand then

 

[carmanmemoranda]

It is a question.

It's a strawman. It's not what he said

 

[denso13]

So, you consider the Welsh 20 limit still to be too high?

I've never claimed that.

 

[motorbiking]

There seem to be two camps here:

1 Its all about impact speed, the best way to reduce impact speed is to reduce free travelling speed. Accidents will always happen, so if we can reduce the speed before the accident, all things being equal we reduce the speed at impact.
2. It's about setting the right speed for every segment of the road, based on what you can see is clear. Speed limits are helpful to set acceptable maximum speeds. i.e. the speed that the majority of drivers would not exceed. A careful balance has to be made between the speed limit and the cognitive engagement of not only the driver but all road users.

 

[ajohn]

Ruddy annoying those 20mph limits on loads of roads where it’s simply not necessary. I experienced queues of cars backed up behind the single car doing 15-20mph regardless of if it was 20, 30 or 40mph stretch of road.

No doubt reducing the speed limit will lower the number of accidents and injuries overall, as would a blanket 10mph speed limit, but there’s a trade off of risk vs rewards (in terms of accidents vs journey time/fuel used). Wales have turned the dial too far to the left in my opinion.

I drive there fairly often and notice the same The reason is pretty simple - they have used a very simple approach but have still had to add 20mph speed limit signs in some cases. The reason for that is signs that were already there. A previous 30 has to go to 20. There are no thoughts about accident rates in the areas that have changed or the current speed variations in the roads concerned. They mention various reasons for doing it but the over riding one is none specific "accident" reduction. Some have posted links that indicate the relationship between pedestrians and 20mph limits. The main gain. One mentions why 30mph was chosen and mentions complications relating to age. One mentions 3 types of drivers and degree of speeding. It really needs breaking down more but the nut cases are a relatively low proportion and other factors will figure anyway.

There is long term data around. This one is finalised

Reported road casualties Great Britain, annual report: 2022

www.gov.uk

It shows signs of covid's effect but in other cases various sections may need to be compared with each other as well.

 

[motorbiking]

Historically we had Restricted roads, National speed limit roads and other roads. In 1991 Guidelines were produced saying that if a road was to be changed from Restricted or National it should be done according to the 85th percentile of speed. That is the speed that 85% of drivers using the road choose to drive. In around 2003 this guidance was reduced to Mean speed thus placing almost half of the road user above the limit. There was an argument that mean spead and 85th%ile are usually the same. Where they weren't, guess what there was an argument for lowering the limit. Over the last 20 years or so, the vast majority of roads have had speed limits reduced and prosecutions have increased dramatically over the same period.

Of course there will be 100s of National Speed limit country roads where the max safe speed would probably be 40-50mph due to the visibility and shape. But looking at casualty data, it vert much looks like every benefit that could be achieved, was done over 10 years ago. Most of the big cuts to speed limits 30-20 and 60-40-30 have occurred more recently. They simply don't seem to make much difference. At the same time primary safety in vehicles has developed massively. ABS, Cameras, brake assist. air bags etc. etc.

This particular approach in Wales was largely political. Local government largely set speed limits not the National government, so the Welsh government had no power to impose 20mph. The only option was to change the definition of a restricted road which is how they achieved their blanket reduction from 30-20mph. I suspect, because there is an election looming, they are keen to show flexibility and success.

If you strip away the lobby groups, the casualty stats long term show these approaches don't seem to work.

 

[ajohn]

A careful balance has to be made between the speed limit and the cognitive engagement of not only the driver but all road users.

True but conditions matter as well. 2 parties are needed for an accident even if the one for a car is a tree, Or simply out of control and leaves the road.

It all gets rather complicated to we finish up with speed limits that actually are fairly well thought out and in some cases need some thought eg bends. There will usually be warnings in more extreme cases. Cars - side impacts are unfortunate not helped by seat belts. Usage is a compromise based on statistics. The speed limits are as well.

20mph - what is the objective and if some one did come up with a sensible definition of a residential road or street how would it be enforced? A lot of speeding tickets would be needed on rather a lot of roads. In some areas actual speed indicating signs have helped. The new idea rather than loads of hidden portable speed detection systems. They are around were i live and they help but not for some drivers if conditions allow. The gov asked the police to back off on the cameras. My brother had an interesting experience. Went out on a Sunday morning decent roads and little traffic. He collected enough points to be banned in one trip for marginal infringements. It wasn't a long trip. He was awarded 1 point less than a ban. This caused him to notice that loads of people travel at an indicated 70 on motorways. He might have exceeded that but not by a lot if conditions allowed.

Actually at one point the police may not have been bothered about 90mph on motorways when changing speed limits were being looked at. Then Blair said this 90mph must stop and out came the cameras especially in Wales. I've had direct experience of that as I usually drove in England. The police were happy but 90 needed relating to conditions and drivers. The Tory thought about 80 but ditched the idea. Labour wondered about a blanket 50 but decided it would upset too many people. They may have also wondered what it would achieve. More congested motorways would figure. Effect on 60mph roads? Like 20 it would need to be tried large scale to find out.

 

[motorbiking]

The more we rely on speed limits to tell us the safe speed for the conditions, the less we can rely on road users to concentrate.

You only have to look at the standard of driving on German motorways vs UK motorways.

 

[ajohn]

From the finalised gov report I posted a link to.

It clearly shows that changes can have an effect but doesn't split up the fatality types at all. Where that is done it's over a much shorter period and doesn't really split those enough. The graph is a too simplistic view.

 

[motorbiking]

The data is there if you want it. The last 10-15 years of speed limit reductions have done bugger all against a backdrop of huge improvements to vehicles.

 

[carmanmemoranda]

The more we rely on speed limits to tell us the safe speed for the conditions, the less we can rely on road users to concentrate.

You only have to look at the standard of driving on German motorways vs UK motorways.

And that's the real issue

Until driving standards, and implementation of rules against bad driving happen, you are stuck with speed limits being the only real issue policed/anpr'd on the roads.

And the limits go lower