20 mph speed limits

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vbsydenham
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Location: Edinburgh

Re: 20 mph speed limits

Post by vbsydenham »

A timely study of the 20mph zone introduced in Bristol:

http://www.bbc.co.uk/news/uk-england-bristol-43050841

There is a debate to be had about which streets and roads are appropriate as 20mph zones. And I'm definitely not in favour of a blanket approach. But on any street on which people live and work in any serious numbers, I can't believe there are still people out there resisting.

And, as Stuart has pointed out earlier, in a city like London where the average speed is 13mph, all a 20mph zone is doing is 1) Ensuring that you spend less time sitting in queues at junctions and 2) Making the environment safer for everyone else around you.
stuart
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Re: 20 mph speed limits

Post by stuart »

se23.life wrote:
Your other stuff is mostly wrong too.
Which bits are wrong?
How about your claim that that limiting speed to 20mph increases the danger to the most vulnerable road users when the evidence is the other way. Not just that KSI is reduced > 40% but they are reduced more than the average reduction ~ 40%.

That's a peer reviewed widespread study of matched London residential streets with limits of 20 and 30 mph. The 20 mph was enforced by passive measures aka road humps. This study appears to have disappeared behind a paywall and/or DoT/TRL reorganisation but there are plenty of others in support. Here are a few: https://trl.co.uk/sites/default/files/TRL215.pdf

You also referred to the Bath study which contradicts your assertion as they didn't appear to have any enforcement, hence no significant reduction in speed or KSIs yet. It instead emphasises the current need for enforced limits or a change in social attitudes to speeding. So we have a three way choice - make speeding socially unacceptable as we have done for drink driving and smoking, put in sleeping or none sleeping policemen for enforcement or continue to accept tens of thousand needless KSIs per year?

What choices would you make?

Stuart
The Clown
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Re: 20 mph speed limits

Post by The Clown »

Obviously an emotive subject for some who are very fixed in their opinions.

I understand what Gillyp was trying to say before she was pounced on.
i.e. the psychology of positive / engaged driving as opposed to the disengaged dawdling at low speed.
Each driving style may suit one individual, but not another.

Speed is just one factor of good driving - Good drivers know to adjust their speed according to the road and circumstances.

If somebody doesn't think they can drive safely at 30 mph, then I agree they shouldn't.

I would like pedestrians to use the designated crossings. They often don't.

What I have noticed is that I prefer to head Bromley way now to avoid the 20mph zone, so in that sense it is working. Bell Green shops get less custom.

Statistics are just, statistics. They are used as guidance, not mantra.
vbsydenham
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Location: Edinburgh

Re: 20 mph speed limits

Post by vbsydenham »

Is there some common ground that we can find here?

For example, do we agree that London has a problem with road safety? And do we agree that a major component of that problem is excessive speed? There is plenty of evidence to back up both of those positions.

So if speed restrictions are not the answer, then what is? Or is it just the specific type of speed restrictions that have been implemented locally that is the issue?
robbieduncan
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Location: Trewsbury Road

Re: 20 mph speed limits

Post by robbieduncan »

I can anecdotally support the enraged driving from something I witnessed this morning. An idiot in a blue VW golf or maybe polo was driving down Trewsbury road at just before 8am this morning inches off the bumper of a Tesco delivery truck. I would visually estimate the truck was keeping to the speed limit. This was obviously causing the VW driver significant distress as he was as far on to the wrong side of the road as he could be beeping his horn and waving his arms around.

However be was not able to pass. Until he reached the end of the road where he accelerated round the right of the truck and cut left across the front of the truck bwfore accelerating up Sydenham Road.

By the time I walked to the end of the road he had gained nothing from his aggressive and somewhat dangerous driving. He was waiting to turn right at the lights. Which he did immediately when the lights turned green in front of the traffic accelerating towards him away from the lights.

Now as much as I think the 20 limits are a complete waste of money and achieve little they are not the cause of this driving. The driver is the one who chooses how to drive
JRobinson
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Re: 20 mph speed limits

Post by JRobinson »

jrobinson wrote: - email to Abellio
Good afternoon,

As part of my research into driver behaviour, please could you tell me the number of bus drivers who have been given speeding tickets or fines, within the London boroughs that have become whole borough 20mph zones, since becoming 20 mph zones?

Broken down by year please, where available, and also any other speeding tickets, in 20 mph zones outside of those boroughs, also broken down by year, as far back as you’ve got data for, if possible, or at least the last 5 years.

Please treat this as an FOI request if necessary.

Many Thanks in advance for any help with this.
Reply
customer.care@abellio.co.uk wrote: Dear J....

Thank you for your email, unfortunately we can’t provide this data.

Regards
Janet
I shall reply, and ask specifically why they can't, but this is a poor response.
vbsydenham
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Re: 20 mph speed limits

Post by vbsydenham »

You should look up and contact Tom Kearney @comadad - He may have the info you're looking for. If not he'll certainly have already tried and have been through all the arguments why it hasn't been released (spoiler alert: Abellio will be hiding behind DPA legislation).
JRobinson
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Re: 20 mph speed limits

Post by JRobinson »

yes, Data Protection Act might be relevant, however, they could anonymise the data, and I didn't ask for anything that would identify anyone, I just wanted numbers per year, and the reply was way below (what I suspect is a legal minimum for) what is expected as a response for an FOI request. I deal with FOI requests at work, and the amount of red tape we have to go through to ensure that we're responding properly is ridiculous, and to see this one line response of 'sorry, we can't provide that data' is just a bit crap really.
Andyb
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Re: 20 mph speed limits

Post by Andyb »

Living off lawrie park road which is 30/20 speed limits I very rarely see any sticking to below 30 let alone 20 and with many parked cars espically along by hospice it’s an acccident waiting to happen!
stuart
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Re: 20 mph speed limits

Post by stuart »

Andyb wrote:Living off lawrie park road which is 30/20 speed limits I very rarely see any sticking to below 30 let alone 20 and with many parked cars espically along by hospice it’s an acccident waiting to happen!
Its already happened! In the time I have lived here at least six people have been killed in speed related crashes on LPR. So what do we do about all this blow back when trying to limit speed for safety's sake?

Its not as though we are gaining anything as we usually have to queue either end.

Stuart
JRobinson
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Re: 20 mph speed limits

Post by JRobinson »

lobby your local council(s) for some passive speed reduction measures. chicanes, road narrowings, humps, etc.
stuart
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Re: 20 mph speed limits

Post by stuart »

JRobinson wrote:lobby your local council(s) for some passive speed reduction measures. chicanes, road narrowings, humps, etc.
It would probably be resisted by TfL as a busy double decker route. Plus the complication of two councils with little/no money to spend on discretionary schemes. A camera would only cover a 100 yards - so speed reduction here (and most of Sydenham), has, I would have thought, to be successful been primarily a change in driver attitude.

But we have some hereand more out on the road unhappy to slow a little and seemingly impervious to the evidence or the physics. I guess my frustration is showing a little at the lack of will to accept and deal with the problem a couple of magnitudes greater than domestic terrorism.

But we did it with smoking. It took 50 years which was a shocking waste of lives. Is this going to take another 50 or when robots eventually takeover the wheel and are programmed to drive within the rules?

Stuart
vbsydenham
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Re: 20 mph speed limits

Post by vbsydenham »

Lawrie Park Rd shouldn't even be a thru route. Instead it is allowed to be a magnet for rat runners with no regard to those actually living in the surrounding streets. It wouldn't cost the boroughs any serious money to put a couple of bus sensitive bollards in halfway down. A Heretic writes...
JRobinson
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Re: 20 mph speed limits

Post by JRobinson »

lol - just received a reply from customer care at Abellio - they misunderstood. When I said 'number of drivers' they thought I meant the individual identification numbers of those bus drivers who'd had tickets - not, as I intended, an anonymous count of the number of tickets.
syenhamboy
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Joined: 26 Aug 2016 03:33

Re: 20 mph speed limits

Post by syenhamboy »

stuart wrote:
Andyb wrote:Living off lawrie park road which is 30/20 speed limits I very rarely see any sticking to below 30 let alone 20 and with many parked cars espically along by hospice it’s an acccident waiting to happen!
Its already happened! In the time I have lived here at least six people have been killed in speed related crashes on LPR. So what do we do about all this blow back when trying to limit speed for safety's sake?

Its not as though we are gaining anything as we usually have to queue either end.

Stuart
Speed related? or pedestrians not paying attention when crossing the road?
I cannot see how anyone can be hit by a car if they're paying attention when crossing a road.
stuart
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Re: 20 mph speed limits

Post by stuart »

syenhamboy wrote:
stuart wrote:
Andyb wrote:Living off lawrie park road which is 30/20 speed limits I very rarely see any sticking to below 30 let alone 20 and with many parked cars espically along by hospice it’s an acccident waiting to happen!
Its already happened! In the time I have lived here at least six people have been killed in speed related crashes on LPR.
Speed related? or pedestrians not paying attention when crossing the road?
I cannot see how anyone can be hit by a car if they're paying attention when crossing a road.
No. There were no pedestrians involved. They were all in or on vehicles. That's the point - if they had been around they would be dead too. Try bicycling along that road - the parked cars and the excess speed make it a very uncomfortable experience for confident riders. New riders would likely never do it again.

Driving at 20 or 30 mph along there means you get overtaken and the supposedly restrictive keep left bollards just get taken on the wrong side. All to no real benefit to anyone. So what do we do with the 80% (which appears to include some pundits here) who just don't obey any speed limits? Or recognise that even 30 is fatal where 20 mph is survivable for vulnerable road users.

Frankly your suggestion of victim blaming pedestrians is a very worrying abnegation of responsibility. Its the two tons of metal that kills. Isn't it the drivers responsibility to be in charge of it and anticipate the actions of others? At 20 mph they are far more able to avoid contact or mitigate it when impossible. Remember that when your kid runs out into the road without looking. Which all kids do - as well even adults do occasionally. Or are you a strict Darwinian?

Stuart
vbsydenham
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Re: 20 mph speed limits

Post by vbsydenham »

TFL's own analysis shows that there are many, many KSIs every year in London where the person walking across the road is not at fault. So not only is the statement pretty appalling victim blaming, it is also just fundamentally incorrect.
Pally
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Re: 20 mph speed limits

Post by Pally »

Well the desperately sad incident with two young children might be an example of someone being hit even though paying attention ...if reports are correct
alywin
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Re: 20 mph speed limits

Post by alywin »

stuart wrote:Studies show that reducing speeds to 20 mph DECREASES pollution because of the reduction in wasted accelerations/deaccelerations in urban areas. Do you really think you know better than NICE: https://www.nice.org.uk/guidance/ng70/c ... -reduction
Actually, having had a family member on the wrong side of one of NICE's guidelines for the past decade or so, and battled tooth and nail to get them appropriate treatment, rather than the treatment NICE claimed would work but only made things far worse, I don't automatically assume that NICE is the authority in anything, so in that particular case at least I know better than NICE. There is always the possibility they are wrong, although perhaps not in the case you quote.
JayB
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Location: bell green

Re: 20 mph speed limits

Post by JayB »

alywin wrote:
stuart wrote:Studies show that reducing speeds to 20 mph DECREASES pollution because of the reduction in wasted accelerations/deaccelerations in urban areas. Do you really think you know better than NICE: https://www.nice.org.uk/guidance/ng70/c ... -reduction
Actually, having had a family member on the wrong side of one of NICE's guidelines for the past decade or so, and battled tooth and nail to get them appropriate treatment, rather than the treatment NICE claimed would work but only made things far worse, I don't automatically assume that NICE is the authority in anything, so in that particular case at least I know better than NICE. There is always the possibility they are wrong, although perhaps not in the case you quote.
Alywin, I totally agree with your reservations about NICE always being right. Thye can only go on the best available evidence at the time and scientists agree that the behaviour of NOX emissions has not been factored into many previous pollution studies.

Regardless, NICE still advise avoiding speed humps altogether even if physical means to reduce speed are needed- which they still suggest circumventing precisely because the driving patterns they create categorically do increase fuel consumption and air pollution It's there in the link to their study posted above.
So, it is perhaps not quite as black and white as some make out. But then how would we all tell everyone else what they should think if we go down that road? :roll:
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