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We want propose to introduce a 20mph speed limit on restricted roads across Wales.
Restricted roads include street lights placed no more than 200 yards apart. They are usually located in residential and built-up areas with high pedestrian activity.
This definition appears to suggest that anywhere that is currently a 30-zone.
Again, I can fully support 20-zones in residential areas, but through routes (and especially A, B and C roads) should not be included. IMHO.
We want propose to introduce a 20mph speed limit on restricted roads across Wales.
Restricted roads include street lights placed no more than 200 yards apart. They are usually located in residential and built-up areas with high pedestrian activity.
This definition appears to suggest that anywhere that is currently a 30-zone.
Again, I can fully support 20-zones in residential areas, but through routes (and especially A, B and C roads) should not be included. IMHO.
I think it has been mentioned, but as with any area that introduces blanket 20 limits, they're setting themselves up for mass non-compliance with the limit resulting in contempt for speed limits generally. It's not been fully thought through.
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Blanket rules are easier to follow and don't result in an expense of explanatory signs, but blanket rules don't take account of individual circumstances.
Residential roads that are not routes across town should probably be 20. I usually don't drive faster than that anyway. One important question is who or what the roads are for.
I would think 20mph limits are likely to be less accepted in larger built-up areas where some people could be driving for several miles on roads affected by them. In small towns, you can usually be out of the built-up area after 5 or 10 minutes even at 20.
gchree wrote: ↑Sun Dec 26, 2021 15:22
Scotland has largely done this without much controversy
Are there stats on compliance? Or are the limits quietly ignored and unenforced?
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I agree that it's more appropriate to save 20mph limits for medium-high risk areas (residential, commercial streets, nightlife areas and areas with a lot of gig delivery traffic are all more than justified 20s in Bristol) but high capacity 30mph through routes should remain as such. There are interesting modern problems created by blanket speed limits, including encouraging rat running. Sat nav users and some clued in locals may be more likely to use or be directed to side roads that are also 20mph. This isn't just supposition - it happens often in Bristol where old roads like the A38 have parallel residential roads, all now at exactly the same speed limit despite having hugely different uses and journey profiles.
This policy is well meaning, but I think it will create too many really dumb situations where roads are inappropriately limited, and of course, compliance with 20mph limits is both too low and currently difficult to enforce. The existing policy of rolling out 20mph limits in appropriate locations, for example by estate/district as has long been happening in many cities, was working fine. The only minor issue was with poor signage standards, but then, where is that not an issue right now?
Last edited by DB617 on Sun Dec 26, 2021 16:16, edited 1 time in total.
I wouldn't mind a presumption of 20 for unclassified urban roads, with an easy ability for local authorities to set 30 limits or zones without difficult planning hurdles. I'm sure we've all been on wide, good quality through route 20s (hello Jedburgh A68!) and I don't think that helps broader compliance of these limits.
gchree wrote: ↑Sun Dec 26, 2021 15:22
Scotland has largely done this without much controversy
This has been done de facto in some parts of Scotland, yes, but an attempt to do the same thing as here - set the urban default to 20mph - failed a few years ago.
trickstat wrote: ↑Sun Dec 26, 2021 15:53
I would think 20mph limits are likely to be less accepted in larger built-up areas where some people could be driving for several miles on roads affected by them. In small towns, you can usually be out of the built-up area after 5 or 10 minutes even at 20.
London is an example of how not to do it, with little in the way of consistency, limits changing arbitrarily at local authority boundaries, and without taking into account the build quality of the road or whether it has separated cycle provision etc. etc.
trickstat wrote: ↑Sun Dec 26, 2021 15:53
I would think 20mph limits are likely to be less accepted in larger built-up areas where some people could be driving for several miles on roads affected by them. In small towns, you can usually be out of the built-up area after 5 or 10 minutes even at 20.
London is an example of how not to do it, with little in the way of consistency, limits changing arbitrarily at local authority boundaries, and without taking into account the build quality of the road or whether it has separated cycle provision etc. etc.
Hans Monderman (of 'shared space' fame) also devised something called the 'Staircase of Monderman', which relates how long a driver is willing to drive at a certain speed. E.g. drivers are happy to drive on roads with a speed limit of 30km/h (access roads) for approximately 6 minutes, after which they want to put their foot down. The actual steps are; 6 minutes for access roads (30-60km/h), 9 minutes for distributor roads (50-80km/h) and an unlimited time for through roads with a speed limit of 100km/h or more. This suggests that drivers on a through journey should be on 100km/h roads after 15 minutes otherwise they're tempted to go faster despite the speed limit.
trickstat wrote: ↑Sun Dec 26, 2021 15:53
I would think 20mph limits are likely to be less accepted in larger built-up areas where some people could be driving for several miles on roads affected by them. In small towns, you can usually be out of the built-up area after 5 or 10 minutes even at 20.
London is an example of how not to do it, with little in the way of consistency, limits changing arbitrarily at local authority boundaries, and without taking into account the build quality of the road or whether it has separated cycle provision etc. etc.
Hans Monderman (of 'shared space' fame) also devised something called the 'Staircase of Monderman', which relates how long a driver is willing to drive at a certain speed. E.g. drivers are happy to drive on roads with a speed limit of 30km/h (access roads) for approximately 6 minutes, after which they want to put their foot down. The actual steps are; 6 minutes for access roads (30-60km/h), 9 minutes for distributor roads (50-80km/h) and an unlimited time for through roads with a speed limit of 100km/h or more. This suggests that drivers on a through journey should be on 100km/h roads after 15 minutes otherwise they're tempted to go faster despite the speed limit.
It's almost laughably childish, isn't it? An illustration of the myth of "driving to conditions" - really, the average driver drives to their own impatience.
So, what should you do? Do you take account of real-life human behaviour, or do you try to bully them into submission with oppressive enforcement of unrealistic limits?
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This is actually worse than you think, normally with 20mph schemes there's a network of higher standard roads left out, often there's non-uniformity that ensues, such as in Bristol there's 30 limit roads that are a lower standard than many 20 limit roads and vice versa.
Cardiff, unlike most cities with 20mph schemes, have not gone about creating a network of higher standard and main roads that are exempt, they have just gone and made the whole network 20 with little to no regard for differing road standards, even including some roads that seemed under-posted as a 30 limit. I've know this to get the back up of 20mph advocates.
I was in Caldicot the other day and they have done the same, even including the Caldicot bypass. I filled a FOI request and it turned out the level of non-compliance with the 30 limit there had been 97% before they dropped the speed limit.
jnty wrote: ↑Mon Dec 27, 2021 12:31
It's almost laughably childish, isn't it? An illustration of the myth of "driving to conditions" - really, the average driver drives to their own impatience.
OK, let's say that's true, what difference does dropping the speed limit make?
From my own point of view, I once had my GF measure what sort of speed I drove around the side streets of Shirehampton in Bristol. These are not main roads, just ordinary residential streets. Apparently I mostly hovered at about 23 going down to 18 and maxing at 25.
If I sit on Stockwood Road on the other side of Bristol, a road that genuinely has an issue with speeding, so the council lowered it to 20 to "do something about speeding".
I see so many people fly past me at speeds close to 40. They way the council have tried to deal with it is not to target them, but to prohibit my normal driving behaviour.
Abergavenny was one of the towns selected to try out the 20 mph zones before their widespread introduction and I noticed for the first time I went to the town recently its almost a blanket 20 mph everywhere, such as this street on the A4143, which used to be the former railway line and has no residential properties, a few industrial units and only the occasional pedestrian. https://goo.gl/maps/MYUUu6BuMCmviJNB7
30 mph used to feel slow if it was quiet and at 20 mph you feel like jumping out of the car and running quicker!
I live in Wales and near a pair of flat-top-three 30mph signs. If this goes ahead I might have to go down there with a spanner to save them before they're scrapped.