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jnty wrote: ↑Tue Oct 03, 2023 15:17
It's not credible to argue that blanket speed limit rules are bad and the design of a road should be taken into account and then, when a council takes the design of the road into account when setting the speed limit, argue that there should be a blanket speed limit based on the road's classification.
That isn't actually what I said. I was arguing that classified roads should be *exempt* from "blanket" 20 limits unless there's a darned good reason for 20 on a particular stretch. And I referred to the *function* of a road, not its design.
You are seeking a blanket exemption for roads based on classification - which can be pretty arbitrary in urban areas - from speed limits determined by road design.
Of course road design should match road function, but in many urban areas physical constraints make this aspirational. Skipping the design part and just whacking up the speed limit only serves to add insult to injury for local residents in these cases.
If anything, the classification of a road is a reason to drop a limit. 60mph limits are fine for many quiet single track roads, but if a single track road actually forms the narrowest part of a busy trunk road it would be reasonable for it to have a limit far lower than that.
Did you read that back after you typed it? In general, roads of higher classification should be expected to have higher speed limits, so that through traffic is encouraged to use them in preference to unclassified roads. The situation that we find in some areas of England where the A road has a 50 limit while all the side roads are NSL is bonkers to my way of thinking. However, what you then go on to describe is an exceptional situation, although perhaps less so in Scotland. If you have a single-track section of a busy A road then I would suggest traffic light control rather than just a low speed limit. But such situations in England and Wales tend to be limited to narrow bridges and occasional tunnels.
We do suffer from too much micromanagement of speed limits; the principle used to be to sign the hazard up ahead and expect motorists to deal with it, but that's apparently out of fashion these days. But I guess if you take away the responsibilities of local government and just leave them with speed limits to play with, that will be what they do.
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That has a great deal less to do with local authority powers than with incompetent drivers, and also with the fact that resources are never going to allow local authorities to risk assess all (or any) of the NSL minor roads which connect to 50mph A roads for a safe speed limit. Add to that that in reality many minor roads have stretches fit for 50-60mph between oncoming vehicles and bends, without the roadside development now common on rural A roads.
Even in the days when local authority funding could cover wholesale realignment to reduce risks, at many times the cost of a vandalised LTN, there was always a reality gap between what funding was available and what was desirable.
Chris Bertram wrote: ↑Tue Oct 03, 2023 19:40
The situation that we find in some areas of England where the A road has a 50 limit while all the side roads are NSL is bonkers to my way of thinking.
It's only bonkers if you subscribe to a "painting by numbers" approach to speed limit setting. Speed limits should match the risk at a given location, and - as I've pointed out several times in these various speed limit-related threads - risk is a combination of likelihood and consequence, not just the latter.
The likelihood of a given outcome in terms of deaths, injuries, damage and disruption on a road with very little traffic is very small. Moreover, the vast majority of that very small number of users are likely to have a reasonably functional sense of self-preservation, which prevents them from hooning along an S1 with zero visibility at 60 if they think they'll die. So even if you did risk-assess all the goat tracks leading off 50-limited A roads, you'd probably arrive at the same result as we have now.
Whether any given 50 limit on a rural A road is sensible and the product of a proper risk assessment is of course open to question. But in principle it's entirely possible for such a road to receive a 50 limit as a result of impartial, scientifically rigorous analysis, where the same standard of analysis on the side roads would suggest NFA.
It seems that both sides of this culture war want to paint by numbers. You've got one lot who say because a road is within some definition of urban settlement it absolutely must be 20 in defiance of any logic, and another saying roads can't possibly be limited to anything other than 60 because they're classified. By all means use these kind of criteria as a starting point for more detailed planning, but we should all avoid slavishly following any of these characteristics - at the end of the day, none of them is a substitute for actual evidence-based assessment.
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rhyds wrote: ↑Mon Oct 02, 2023 13:06
This morning I finally kicked my grumpy old man mode in to gear and sent out some emails to both the local council and the trunk roads authority to try and get the mess that is our local VSL signage sorted
In short, the B-road through the village T's off the Trunk road next to the school. Therefore the east/west arms of the T are trunk and are 40mph normally and 20mph at school start/finish times, and the southern arm was 30/20 for about 100 yards or so before a pair of terminal VSL signs showed either 30mph (if the 20 limit was active) or were blank (if it was 30, because no repeaters in a 30 zone).
Now with the rule changes the southern arm is now 20mph constantly, however the VSL signage still shows 30MPH outside of school times, and then shows 20 in the old 20 zone before showing a pair of terminal 30s. Therfore you would think the village still had a 30mph limit. Problem is, at the other end of the village (About a mile) there's a pair of standard fixed 20 signs, so the limit is definitely 20 and the VSLs either need to show a permanent 20 or be removed and replaced with proper signage.
What doesn't help is the VSLs on the trunk road seem to randomly decide when and what they'll show, and you get the odd sign showing 20mph rather than 40/blank at 6pm on a sunday, forcing traffic to slow down, or like this morning at 9am when the western arm of the T showed a 20 limit but the eastern was at 40.
The other issue is that despite the system being an integrated set, the signs themselves are controlled by two different authorities. The trunk road signage is controlled by NMWTRA while the B-road is a Gwynedd CC road, so its their signage. We know this because for about a year there were VSLs on the trunk road slowing you to 20, but none past the school so you'd be allowed to speed up to 30 past there!
Good work, these sorts of problems should've been ironed out before the switch-over!
I noticed this morning that at least one part of the VSL setup had been turned off and a pair of temporary "Sandwich Board" 20 signs put up. Personally I'd have just locked the installed VSLs to permanent 20, but I'm glad to see something has been done.
FosseWay wrote: ↑Tue Oct 03, 2023 17:15
But I expect an honest explanation of what the aim and the actual performance of the scheme is. I object to having my name taken in vain, as it were, by campaigners for lower limits who state as if it were a truth universally acknowledged that all speed limit reductions are good for cyclists.
I would suggest that the chances of an honest explanation of the performance of the scheme are vanishingly small. There is too much political capital bound up in this scheme for an independent analysis to be commissioned. That is if there is anyone capable of carrying out a truly independent analysis - any organisation with the ability is likely to to have a vested ideological interest in the outcome.
This reminds me of a radio interview I heard a few years back following the introduction of strict blood-alcohol limits for drivers in Scotland. One of the driving reasons behind the scheme was that it would clearly lead to a reduction in accident statistics in Scotland and, if that had been the case, I suspect that the interviewee (who was one of the people behind the rule changes) would have claimed it was a direct consequence of the new rules. But - guess what - in the year following the new rules, the accident statistics had actually gotten worse. No problem for the interviewee - they simply glossed over the statistics, claimed it was an anomaly and stated that they were confident things would change in the future. That's as far as accountability goes in this particular world.
Your point about motorists ability to overtake cyclists in 20 zones is a good one, and should surely be given more prominence. It does mean that the figures being banded about in this thread about the time taken to drive x miles in a 20 zone vs a 30 zone are more complex than simply multiplying x by 2 or by 3. It also means that there is a real possibility of accidents occurring in 20 zones that simply would not have happened in 30 zones, as a consequence of driver frustration, or drivers taking their eyes off the road in the middle of an overtaking manoeuvre to check that they were not exceeding 20mph.
ajuk wrote: ↑Tue Oct 03, 2023 00:01
As predicted there is plenty of non-uniformity out there.
In Port Talbot, the A48 has been exempted despite it being a road lined with houses, I think the council have ignored the guidelines to do this, in Newport and Cardiff they have included some very high-standard roads including a few former 40-limits.
There are some parts of the valleys that don't have bypasses and there can be a several-mile urban journey just to get there. Of course it would make sense to make these exceptions but I doubt they have.
In many cases I'm not sure it would make sense, because of the number of tight frontages (lots of mining properties without even front gardens, just opening onto the road) and cars parked along the major routes. But it varies a lot based on the valley and indeed on the mining companies who built the different towns. For example, the road from Bridgend and Maesteg is long and tortuous, mainly because one rarely gets above 20mph due to the constant meeting situations on the main route. It could be argued that the lower speed limit wouldn't have much of an impact at least at busier times in a place like that. On bin day you would rarely get above 10mph.
Why aren't people expected to judge their speed correctly based on these factors?
This also implies speed limits are meant to be used a "traffic calming", they were never intended to be used this way, the fact people assume that's what they are is what leads to them being set artificially low.
I doubt there will be a reversal of this scheme, I think the rules that prohibit taking into account traffic speeds and the inclusion of so many higher-standard and main roads will likely be revised at some point.
There's good reason why you look at traffic speeds as a function as to how you set speed limits, it's simply that no one previously hadn't considered to disregard them.
AAndy wrote: ↑Mon Dec 11, 2023 17:42
Where is an example of a WAG blanket 20mph speed limit?
I put forward Penderyn in Rhondda Cynon Taf.
Visually, I'd judge all but about half a mile of that as being a 40mph (or above) design.
Outside the School a Variable 20/40mph is used in other areas that are more built up. Example: Garth on the A483.
Most of the road is not the village itself , the main road bypasses the roads leading to most houses. Example: Garthmyle nr Welshpool (with a 50mph limit)
Nathan_A_RF wrote: ↑Mon Dec 11, 2023 18:24
So change the design of the road. Get rid of the hatchings, widen the footways, add more trees etc.
And it's not a blanket limit.
The road has excellent visiblity, why change?
The blanket limit refers to the 20mph being imposed without consideration for a specific location. Perhaps its not, just an example of of somebody in power who prefers to slow down vehicles a lot.
Big L wrote: ↑Mon Dec 11, 2023 18:44
Maybe 3-D speed bumps might be an idea rather than this painted nonsense. IMG_1087.jpeg
If I remember correctly were installed when it was a 40mph speed limit.
The example in the video seems consistent with WAG policy:
Pre 20mph limit the road is a restricted road so falls within the policy of being subject to a 20mph speed.
For the road not to fall within the policy an exception has to be considered for which there is a WAG policy:
<<
2.1.3 Two principal questions, A and B below, should be considered by highway authorities when deciding whether a 30mph exception should be made:
Question A: Are there significant numbers (or potential numbers, if speeds were lower) of pedestrians and cyclists travelling along or across the road?
If the answer to A is ‘no’ then an exception for a 30mph speed limit may be appropriate.
Question B: If the answer to A is ‘yes’, are the pedestrians and cyclists mixing with motor traffic?
If the answer to B is ‘no’ then a 30mph speed limit exception may be appropriate.
If the answer to B is ‘yes’ then a 20mph speed limit will be appropriate unless the robust and evidenced application of local factors indicates otherwise.
2.2.1 Decisions on exceptions should not be influenced by existing traffic speeds.
>>
I suspect that the officers more local may have a better assessment of the pedestrian and cycling numbers but there appears to be a school within the limit to which active travel would be encouraged.
If there is a road which encourages driving at 40mph by a school, then I would agree that the design of the road is at fault rather than the legal limit. I would question the judgement of drivers who choose to exploit this poor design and break the law while in the obvious vicinity of a school however.
AAndy wrote: ↑Tue Dec 12, 2023 07:54
The road has excellent visiblity, why change?
The blanket limit refers to the 20mph being imposed without consideration for a specific location. Perhaps its not, just an example of of somebody in power who prefers to slow down vehicles a lot.
Because the design encourages faster speeds? Reduce visibility and drivers will slow down.
It will be interesting if you think this is a well thought out 20mph limit or it it was created by the default (blanket) .
I will put up an example in Wales soon where there is no 20mph limit to compare .
Reasonable for the tight section at the beginning, up to about 1'15". Unreasonable thereafter, should be 30/40
I wonder if there is a certain amount of grubby politics going on, where local councils who don't like the idea of the 20 limits are not applying for derogations so as to cause more opposition?
It will be interesting if you think this is a well thought out 20mph limit or it it was created by the default (blanket) .
I will put up an example in Wales soon where there is no 20mph limit to compare .
Reasonable for the tight section at the beginning, up to about 1'15". Unreasonable thereafter, should be 30/40
I wonder if there is a certain amount of grubby politics going on, where local councils who don't like the idea of the 20 limits are not applying for derogations so as to cause more opposition?
"Pulling a Chris Christie" would be tantamount to misconduct in public office, squandering public money on political spite like that should be extremely frowned upon.
Bryn Terminally cynical, unimpressed, and nearly Middle Age already. She said life was like a motorway; dull, grey, and long.
Driving through Penderyn at quiet times at 30 mph seemed too slow. After the first cluster of houses in the video, there's a section from the quarry entrance to the distillery with no properties and 20 mph here is totally unreasonable. There is often a camera van in the layby covering this section, so if it continues to monitor speeds along here, it'll be rich pickings.
If Penderyn is 20 mph, why is it OK for the B4601 out of Brecon to be 40 mph when there are houses along one side of the road? https://maps.app.goo.gl/mvmLnpF8MZAWhMpp8
