If the Tory member is going to argue that this will cost £millions to the economy, perhaps he could elucidate us with that evidence. I am a ROSPA and IAM trained driver, this speed limit change will not hinder progress in built up areas. It will definitely save lives and reduce pollution. In heavier traffic, ruzh hour, it will make not difference.
It's still not the right way to go about it. If you want to make a 20 mph road, then build a 20 mph road - complete with traffic calming measures, as per the official recommendations. Just slapping a 20 sign on a road that feels like a 30 is only going to increase noncompliance (currently measured at ~85% for 20 roads). That's not to mention traffic light systems that have been timed to 30 mph roads, these are never updated when the speed limit changes.
If you want people to change how they drive, then they need training, not altered roads. Hell, even just doing your ROSPA and IAM isn't perfect, because if you don't keep up your training you'll develop bad habits over time.
this speed limit change will not hinder progress in built up areas.
Big assumption, one that doesn't hold up. Travelling at 20 mph takes 50% longer than travelling at 30 mph.
It will definitely save lives
Possibly, in a select few areas. These areas should be identified and addressed properly, which may well save more lives.
and reduce pollution
The difference in fuel consumption between driving at 20 and 30 is negligible. The main economy difference is acceleration, and slowing down and accelerating for 20 areas increases fuel consumption. Hell, the government white paper on speed bumps mentions higher fuel consumption leading to fuel tax revenue as a benefit.
In heavier traffic, ruzh hour, it will make not difference.
Probably not, but that's not the concern here. The concern is about impeding progression when there is no traffic and no good reason, ie an empty road through town in quiet times with few cars or people about.
I'm sure there are some areas that will benefit from a reduction to 20 limits, but a blanket change from 30 to 20 is just poorly thought out political pandering.
The concern is about impeding progression when there is no traffic and no good reason, ie an empty road through town in quiet times with few cars or people about.
The thing is, nobody plans to crash their car into a pedestrian. So how does it keep happening? One reason is from people driving faster than they should because they wrongly believe a road is empty. Slower limits help with this, because when drivers are going around with incorrect beliefs about whether roads are empty or not, there is more time to react and less energy to cause injury
I can't disagree with anything that you're saying here. All I can say is that there is always a balance to be struck between road users - pedestrians, cyclists, cars, everyone (even animals).
So how does it keep happening?
It happens because road users aren't properly segregated. If you look at large construction sites, they have barriers everywhere and it's generally extremely safe. They still have fatal accidents between vehicles/plant and people. The only way to be completely safe is to be separate - but that isn't reasonably practicable everywhere.
My issue here isn't with 20 mph roads. My issue is with a blanket change of all 30 mph roads to 20 mph, without making those roads suitable for 20 mph. Maybe some of these roads already should be 20 mph, but many aren't and shouldn't be, and the ones that aren't will encourage further noncompliance everywhere else.
You can do the maths to work out percentages of a small number. Perhaps check the killed and seriously injured specs, and whilst online, the other technical assessments. Give me more than uninformed view to consider.
I can do the maths, but apparently you refuse to. You're going by what you've been taught about speeding on the motorway, how 80 mph is really very close to 70 mph in terms of time. That doesn't hold true between 20 and 30.
You're not considering anything, you're not arguing the points I've presented, you're just trying to fight me. It isn't working.
If you have evidence that backs up your side of the argument then please present it, like I have with the government's compliance statistics. Don't try to pass off the work for making your argument onto me.
So their key points:
- Drivers cut their spacing as braking distances contract. Shorter gaps mean more vehicles can use the available road space, reducing standing traffic.
- Filtering at junctions becomes easier too. It is far easier for motorists to pull into traffic travelling at 20mph than at 30mph. So junctions work more efficiently and queues reduce.
- Motor traffic volumes decrease since slower speeds encourage active, sustainable and shared travel. Walking and cycling levels rose by up to 12% after Bristol’s 20mph limit[i].
- Buses operate more efficiently. The reduced length of queues means that bus journey times decrease, and become more reliable. Buses become a more attractive alternative to the car.
Don't really relate to 20 all that much.
- The space in distance between moving traffic is irrelevant, the following distance expressed as time will always be the same (~2 seconds). The space between stationary traffic is the same in both 20 and 30 zones.
- Filtering isn't about speed, filtering is about technique. It's about restraining your acceleration and leaving a bigger gap in front. It can be done at any speed - it's what you do when entering a motorway at 70 mph. Reducing the speed limit does not teach people how to filter.
- Bristol is a city, this post is about Wales as a country adopting 20 mph limits. I live near Bristol, and many Bristol roads need to be 20 - they're too narrow and there's too much going on (and that's not to mention the potholes..). That isn't true elsewhere in the UK, and certainly not throughout the countryside, even the countryside immediately outside of Bristol. However, even with the 20 limit, many of the roads in Bristol are not built suitable as 20 mph roads, and compliance in these areas is very low. Even buses do 30 in these places.
- The efficiency improvement for buses is negligible. Drivers let buses out. Again, this incorrectly attributes reducing speed limits to training drivers how to filter and how to drive in traffic.
If you want 20 mph roads, then build 20 mph roads. If you want drivers to drive better, train them.
Just in general, can I ask what you're hoping to get from this thread? I mean, you're in the Fuck Cars community asking everyone to agree with you that today's driving is okay, that there aren't benefits from slowing down motor traffic and that we shouldn't expect people to act legally. It seems a strange battle to choose.
I'm just calling out bullshit political pandering in a blanket speed limit reduction as what it is: bullshit political pandering that doesn't even really achieve the goals it sets out to do.
I'm not against 20 limits, I'm not against increasing safety of vulnerable road users, I'm not against reducing the use of cars. I want those things to be done appropriately and effectively. This is not that.
That whole study is specifically aimed at 20mph. It does reduce speed but not exactly by 10mph. It’s going to reduce traffic time, casualities, pollution and increase walking and public transport use.
There is a lot to like and for the places that it doesn’t apply people can always put up a sign for 30. Ideally this is supported by traffic calming measures but that’s a longer more costly.
Also, if you want to refer to that blog post as a "study", we should look only at its sourced claims.
- Motor traffic volumes decrease since slower speeds encourage active, sustainable and shared travel. Walking and cycling levels rose by up to 12% after Bristol’s 20mph limit [^1]
This is specifically about Bristol, a city with narrow roads.
- Smoother driving with less wasteful braking and acceleration cut fuel use by 12% in Germany after 30kmph (18.6 mph) limits were implemented [^2]
I'm sure Germany have implemented speed limits efficiently, but the UK has a history of compelling local councils to implement traffic measures that increase fuel consumption and thereby increase fuel tax revenue. Regardless, Germany have not changed all of their 50 kph zones to 30 kph, like this law proposes.
- The Department for Transport’s speed / flow plots are in the COBA (Cost Benefit Analysis) manual - Vol 13 of the Design Manual for Roads and Bridges. This computer programme shows that urban traffic flow improves at lower speeds [^3]
Urban traffic flow. This law covers everywhere.
- The FREEFLOW project by the University of York, City of York Council and others... Slough experimented with this successfully in the 1950s on a single arterial road. [^4]
This experiment was from 1950.
- Shared Space also enjoys claims of shorter tailbacks and congestion. The concept relies on cutting traffic speeds to around 20mph or less for ‘eye contact’. Traffic experts Ben Hamilton Baillie and Phil Jones state "tailbacks of traffic during peak periods have also reduced. It seems that the ambiguous junction provides improved capacity for traffic and fewer delays than traffic signal control systems." [^5]
Urban design, referring to handling specific zones of congestion.
None of these points apply to changing the national speed limit for Wales from 30 to 20.
[^1]: Cycling City project and Active Bristol / Monitoring by Bristol City Council http://www.betterbybike.info/sites/default/files/attachments/Cycling%20City%20end%20of%20project%20report.pdf [^2]: An illustrated guide to traffic calming. by Dr Carmen Hass-Klau (1990) [^3]: Link to a copy of the COBA 2002 manual – Traffic Flow plots are in Chapter 9: http://www.leics.gov.uk/part_5.pdf [^4]: http://www.freeflowuk.net/index.php?option=com_content&view=article&id=73&Itemid=59 [^5]: Improving traffic behaviour and safety through urban design. Proceedings of Institute of Civil Engineering. Ben Hamilton Baillie, Phil Jones May 2005 http://www.icevirtuallibrary.com/content/article/10.1680/cien.2005.158.5.39
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If they put up a ton of 30 signs then it probably would be alright. Eg, the main road through a village or town could stay 30, while the main high street and side roads would all be default 20. But that requires more than just a change in law to say "what was 30 is now 20", and they don't seem to be doing this. They're expecting financially strapped local councils to go through a process of assessing and assigning 30 limits themselves, at their own expense. It likely won't happen in most places, they simply can't afford it.
But the UK just released that 85% of drivers exceed 20 limits - particularly in roads that were not designed and don't "feel" like 20 mph roads.
These reductions in speed limits are primarily political, while corruptly funneling money to overpriced contractors and police running deceptive speed traps. They serve to give brownie points to the people patting themselves on the back for doing it, meanwhile they do nothing to actually make the road work properly. They'll just slap a new sign on and paint some lines which flow worse than a 6 year old's scribble.
Yes, they exceed the 20mph rule - by driving at 25. As opposed to exceeding a 30mph rule by driving at 33mph.
It still means fewer pedestrians crippled.
That's completely wrong. Compliance is much better for 30 mph roads, it's pretty much the other way around with 50% exceeding the speed limit but 82% driving less than 35. Meanwhile only 15% of drivers on measured roads follow 20 limits, with 50% of drivers going above 25. Source
It should be noted that the "measured 20 roads" are primarily roads that don't have traffic calming measures, which were designed and built for 30 but have had 20 signs slapped on them - but that's exactly what this proposal is about. When roads are built with the official recommended traffic calming measures, when the roads actually feel like 20 roads, then there's compliance. But that's not what they're doing here.
It still means fewer pedestrians crippled.
That's an issue in specific areas, not in every single part of every single 30 limit.
If you want 20 mph roads, then build 20 mph roads. Provide ongoing training for drivers. Don't just slap a sign up and jerk yourself off over it.
From your own source:
"For the 20mph sites (which are not thought to be representative of all 20mph roads), the average speeds were above the speed limit for all vehicle types, ranging from 22mph to 28mph but below the average speeds seen on the 30mph roads."
So the average speed does decrease, increasing safety. Just because the effect isn't a perfect 10 mph reduction doesn't mean that it does nothing.
This means the proposal is effective, but it could be improved with traffic calming measures.
This means the proposal is effective, but it could be improved with traffic calming measures.
The report goes into even more detail on this, the roads measured were primarily those without traffic calming measures. The overall subtext is that 20 mph roads should be built as 20 mph roads, including traffic calming as per the official recommendations. You shouldn't just slap a 20 limit on a road built for 30 - which is what this post is about for Wales.
What they're doing will increase noncompliance, not only in the areas where the road should be 30 but also in areas where it should be 20. It's a cheap blanket change that's more about political brownie points than actually achieving positive benefits.
Can we start with the 20 legal limit and then work out the infrastructure modifications needed?
Why not start with an assessment of which roads should be immediately reduced, which roads should be modified and then reduced and which roads should be left alone? Why not do that instead of a blanket change that pushes responsibility onto poorly funded local councils?
One measure is very effective and cheap. Every city, town and village in Wales becomes safer very soon by just reducing the speed limit.
Your proposal takes years to implement and incurs a massive cost and inconvenience to shut down many roads for weeks at a time. Just to make sure you reap the entire benefit of the changed speed limit. The extra benefit has a disproportionate cost to the proposed solution.
One measure is very effective and cheap.
It's certainly very cheap, but only very effective in certain places. It's questionable whether it would be cheaper to target those places exclusively.
I mean it sounds like from the figures that you are providing that changing the speed limit from 30 to 20 DOES reduce the average speed of motorists. It doesn't change it from 30 to 20 seems to be your main point, which, yeah, duh.
But if the goal is to reduce it to 25, they should set the speed limit to 25 and work with drivers. The goal should be to encourage and increase compliance overall, not encourange noncompliance with excessive measures in many prominent zones, which will lead to noncompliance elsewhere where it's actually needed.
The fact is, safety isn't the goal here. The goal here is to make a cheap manuever for political brownie points. Whether or not it's effective overall is an unlikely byproduct. Meanwhile, councils have to spend money to untangle the mess of roads that will now have the wrong speed limit assigned, as per road design specifications and recommendations.
But the limits are assigned so that pedestrians don't have to feel what it's like to be ran over
No, they're not. The limits are assigned so politicians can pat themselves on the back and maybe score some votes. Sometimes also so some new speed trap locations can be created, catching people out in areas where the road feels like it has a higher speed limit (although this is perhaps less true for 20 zones).
If the goal was safety for pedestrians then a hell of a lot more should be done than just messing with the speed limit. Like, actually altering the road and including traffic calming measures - like the official recommendations for 20 limits state - and also providing ongoing training for drivers.
Speed limit reductions are often unpopular.
This policy is clearly evidence based. Not playing politics. It's why the conservatives oppose it. They take contrarian positions to fuel outrage, that keeps people voting against their best interest.
It's clearly not evidenced based, because the most recent evidence says that just slapping a 20 sign on a road built for 30 isn't good enough and leads to massive noncompliance.
It does reduce speed.
It's far better and I think far more effective to train competence in drivers.
You are right in the sense that they are popular, but only when compared to the idea of altering infrastructure because speedlimits cost less than building stuff
Increasing the speedlimit is way more popular, hell more people would probably want them removed altogether than decreased
police running deceptive speed traps.
Here's the thing with speed traps.
Turns out that after people have been fined a few times, they suddenly do feel that 20mph roads are 20mph roads.
Almost as if they knew the road was 20mph all along, but decided to ignore the clearly marked speed limit (and often the speed limit warning on their satnav) because they hadn't faced any consequences for it before.
I have seen documented evidence many times that enforcement does NOT alter people's behaviour in a way that persists after enforcement ceases. They simply adapt to the enforcement level, whatever that happens to be. I don't think that enforcement is a reasonable component of street safety. We can't have street daddies on every corner keeping us safe.
The UK Department for Transport estimated that cameras had led to a 22% reduction in personal injury collisions and 42% fewer people being killed or seriously injured at camera sites. The British Medical Journal recently reported that speed cameras were effective at reducing accidents and injuries in their vicinity and recommended wider deployment. An LSE study in 2017 found that "adding another 1,000 cameras to British roads could save up to 190 lives annually, reduce up to 1,130 collisions and mitigate 330 serious injuries."
https://en.wikipedia.org/wiki/Traffic_enforcement_camera
“Our research suggests the growing use of average speed cameras in motorway roadworks and increasingly on sections of A-road is reinforcing the road safety message as they are extremely effective at slowing down drivers. ... “For instance, on the A9 in Scotland the number of deaths has halved since average speed cameras were introduced between Dunblane and Inverness in October 2014.
https://roadsafetygb.org.uk/news/average-speed-cameras-more-effective-study-finds/
All but one of the studies showed effectiveness of cameras up to three years or less after their introduction; one study showed sustained longer term effects (4.6 years after introduction). Reductions in outcomes across studies ranged from 5% to 69% for collisions, 12% to 65% for injuries, and 17% to 71% for deaths in the immediate vicinity of camera sites. The reductions over wider geographical areas were of a similar order of magnitude.
https://www.bmj.com/content/330/7487/331
We can’t have street daddies on every corner keeping us safe.
You can and thanks to the revenue cameras generate, it generates enough revenue to save the tax payer money, and free up the police for other duties.
I have seen documented evidence many times that enforcement does NOT alter people’s behaviour in a way that persists
Given I found plenty of evidence with a 5 second search, is it possible you didn't want to find evidence because you had already come to a conclusion about the effectiveness of speed enforcement?
The UK Department for Transport estimated that cameras had led to a 22% reduction in personal injury collisions and 42% fewer people being killed or seriously injured at camera sites. The British Medical Journal recently reported that speed cameras were effective at reducing accidents and injuries in their vicinity and recommended wider deployment. An LSE study in 2017 found that “adding another 1,000 cameras to British roads could save up to 190 lives annually, reduce up to 1,130 collisions and mitigate 330 serious injuries.”
"Enforcing speed limits in areas that matter leads to better compliance in those areas and a reduction in deaths"
That doesn't mean we should reduce speed limits everywhere, just that we need to enforce safety where it matters.
“Our research suggests the growing use of average speed cameras in motorway roadworks and increasingly on sections of A-road is reinforcing the road safety message as they are extremely effective at slowing down drivers. … “For instance, on the A9 in Scotland the number of deaths has halved since average speed cameras were introduced between Dunblane and Inverness in October 2014.
Mate, the A9 is a beast in and of itself. It's the one road that connects mainland Scotland (Glasgow & Edinburgh) with the rest of the country, if you exclude Aberdeen. When the A9 has a major accident (which happens far too frequently) then you often have to detour 50 miles, easily more if you don't pick the right route first time.
The A9 single carriageway average speed cameras are pretty reasonable, though, more or less. What would be more reasonable would be dualling it all the way, or at least dualling the key accident hot spots, the bottlenecks. Then if they had a crash they could divert to the other carriageway, rather than queueing up traffic for half a day and expecting people to turn around and navigate across the lower highlands.
Suffice it to say, horses for courses. We can have speed regulation and enforcement where it matters, and we can have national speed limits that leave drivers to driver to the conditions. All of these measures of changing the rules are nothing but bullshit though, not when we have no formal system of teaching the new rules to existing drivers.
Ongoing training for drivers is needed. Not necessarily ongoing pass/fail tests, but at least a CBT course every couple years, to brush up on the latest rules if nothing else. This avenue would offer far better safety improvement than anything else.
10mph it is then.
The severity of the punishment does not matter, as long as it meets the bare minimum threshold of being significant enough that it cannot be dismissed (a small fine is meaningless to someone who is wealthy). The only effective deterrent is the certainty of being caught.
Arguably, we should have more enforcement, with far, far less punishment.
Here's the thing about your comment: police don't run speed traps on 20 roads. You're talking bollocks.
Here's the thing about absolute statements: they only need a single counter-example to be falsified. There's a 20mph road about 200m from my front door. There's a police speed trap there roughly once a month. You are talking bollocks.
Interesting, that's the first I've heard of it - at least, aside from temporary 20 zones around schools and the like. I think most forces are avoiding 20 limits because it's legally not that well tested, there's a slightly higher potential for someone to come up with a novel defense. I guess that doesn't stop revenue coming in from people who just take the fines without challenging them.
Could you please tell me, which country are you in? England/Wales/Scotland.
What the heck? In your other comment you say they make these 20 zones to fund corrupt police running speed traps on them... Which is it?
These reductions in speed limits are primarily political, while corruptly funneling money to overpriced contractors and police running deceptive speed traps.
These reductions in speed limits are primarily political, while corruptly funneling money to overpriced contractors and police running deceptive speed traps.
I'm talking generally about speed limit reductions here. Not just 30 to 20, but 60 to 50, 40 to 50 or 40 to 30. Sometimes it's done with valid safety intentions, backed up by data. More often than not it's done as part of some bullshit political project.
From another of my comments:
The limits are assigned so politicians can pat themselves on the back and maybe score some votes. Sometimes also so some new speed trap locations can be created, catching people out in areas where the road feels like it has a higher speed limit (although this is perhaps less true for 20 zones).
I'm not aware of police extensively enforcing 20 zones, but I am aware of police enforcing speed limits in areas where it has been reduced for arbitrary reasons. Quite often these involve civil works that are ludicrously overpriced and under-delivered, which reeks of corruption.
I get your point about drivers exceeding the limit anyway. They trialed the 20mph in our area and on some roads it doesn’t feel like anything has changed.
Hopefully with this put in place first, they can then target areas where people are over and have the legal “backing” to add traffic calming.
I detailed it more in one of my other comments and the government data and graphs can be found here, but yeah the real non-compliance happens when roads are reduced without traffic calming measures. Which basically shows that reducing the speed limit on its own does nothing but criminalise road users.
I doubt that noncompliance can effectively be used to deliver further measures beyond speed limit reductions. Rather, people are going to say "See, your blanket 20 limit doesn't work, you should undo it".
Ultimately I see this as a very cheap but ineffective method at achieving its purported goals, but it's very visual and very cheap so politically it's fantastic.
No, only criminals would be criminalised. These speed changes would be sign posted. A lack of traffic calming doesn't justify speeding.
These changes will bring down the average speed of cars. This difference has a big impact on reducing the likelihood a child dies from an impact. It also reduces the likelihood of an impact occuring.
Your argument of the change won't reap the most benefit so we might as well do nothing is shortsighted. I could be your not shortsighted, rather you don't care and do want any change that might inconvenience cars.
They actually wouldn't be sign posted, the whole point of the change is that the un-posted speed limit will now be 20 instead of 30. So you may see a 20 sign on the entry to the area, but there will be no requirement for repeater signs.
A lack of traffic calming doesn't justify speeding, no. But the official recommendations for 20 limit areas recommend installing traffic calming measures and generally making the road feel like a 20 road. You're supposed to design a road with a speed limit in mind, changing the limit should involve more than just changing one or two signs.
It's not that I don't care, I don't recognise the significance of the effect, and I don't think they're putting in the effort they should be. 20 zones are good and can be effective in a lot of places, but they don't belong everywhere Wales has a 30 limit. Furthermore, this change by the Welsh Senedd puts all the responsibility onto councils to correct the new 20 zones that should have remained 30, at their own expense, with no further funding. What the Welsh Senedd should be doing is giving more authority to councils to create 20 zones where appropriate. Let them reduce the speed limits where it's needed.
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