20 mph limits

[Nimrod103]

I don't wish to start a discussion on the merits of these limits, but I am interested to know just how assiduously they will be policed and enforced. My town has now designated all the residential neighbourhoods as 20 mph zones, and they are putting up the signs in my street now. AIUI there are no fixed cameras which can measure drivers over the 20 limit. There are 5x 30 mph cameras on the 5x main roads into the town, but I am told few of them actually work, though I always obey them as if they did. I have never seen a mobile speed camera in this county.

There is a single borough council midget camera car which is employed to combat illegal parking and use of bus lanes etc, but I don't suppose that it measures speeds. So it is only the police to enforce it, and we never see them. From observation nobody obeys these 20 mph limits, and mostly people drive in the 25-30 bracket, which is perhaps better than the 35-40.

[DrFfybes]

Is it a 20 limit or a 20 zone?

The reason I ask is that 20 zones are supposed to be self enforcing, by the use of humps/street furniture/parked cars and so tended to only be enforced if there was still an accident issue or a lot of complaints, and these days a "Community Enforcement" regime is usually yher first step.

20 Limits are the same as any other speed limit, except I've never heard of a fixed camera being installed in one, although existing cameras are usually left in place.

There should be some automated monitoring kit to measure before and after speeds, I know initial results in Plymouth showed when the limit dropped from 30 to 20 the average speed on the road dropped from about 28 to 24mph, and compliance with the limit dropped from 80+% to about 15%.

Bristol is somewhat keen on their 20s and do have mobile cameras in them, however they don't seem to prosecute cyclists despite their extended stopping distances compared to a car

Paul

[richlist]

I always obey the 20mph limits.
It's not that difficult, you just ease your foot off the accelerator until the speed drops to 20mph or less.

At 20mph anyone hit by a car has a much better chance of survival.

[Nimrod103]

I always obey the 20mph limits.
It's not that difficult, you just ease your foot off the accelerator until the speed drops to 20mph or less.

At 20mph anyone hit by a car has a much better chance of survival.

That was not the question. But according to the post above, 85% of drivers don't. And with what chance of being caught?

[88V8]

20 Limits are the same as any other speed limit, except I've never heard of a fixed camera being installed in one, although existing cameras are usually left in place.

In a village near me, en route to our usual shopping destination, there is a 20mph limit supposedly put in because of the school, but in force at all times.
Two new cameras were put in to enforce it.
There are also speed humps and a chicane.

I suppose it is effective. Certainly it is effective in increasing pollution, as one can no longer drive through in top gear. Not that I do drive through very often, as I tend to avoid speed humps even at the expense of a long drive round. No doubt reduced traffic is also a measure of success.

V8

[Arborbridge]

I don't wish to start a discussion on the merits of these limits, but I am interested to know just how assiduously they will be policed and enforced. My town has now designated all the residential neighbourhoods as 20 mph zones, and they are putting up the signs in my street now. AIUI there are no fixed cameras which can measure drivers over the 20 limit. There are 5x 30 mph cameras on the 5x main roads into the town, but I am told few of them actually work, though I always obey them as if they did. I have never seen a mobile speed camera in this county.

There is a single borough council midget camera car which is employed to combat illegal parking and use of bus lanes etc, but I don't suppose that it measures speeds. So it is only the police to enforce it, and we never see them. From observation nobody obeys these 20 mph limits, and mostly people drive in the 25-30 bracket, which is perhaps better than the 35-40.

I used to live on a road which was 30mph but deceptively fast. They then made the whole area 20mph which was occasionally patrolled by volunteers with speed guns. The Bobby who acted as their "minder" told me that average speeds had dropped by 10%. However, my own observations based on frequent walks and back to Waitrose on that road suggested that there was a very high lack of compliance (almost 100%) and that many people were still doing of the order of 35-40 mph.
The police weren't interested which is regrettable and they only had speed indicators which drivers knew wouldn't "book" them for speeding. I think the only way to get people to obey would have been a blitz every month or two and handing out tickets, otherwise people know nothing will happen. Hit 'em where it hurts!

Arb.

[DrFfybes]

I suppose it is effective. Certainly it is effective in increasing pollution, as one can no longer drive through in top gear.
V8

2 of our cars change down at 50mph, let alone 30. This does make me wonder about the efficiency of the 50 limit on the A5 at Wrexham installed to reduce pollution. 60 might have been better.

Paul

[didds]

Its not different to many laws that are in effect unploiceable and unenforceable. And reliant on a mixture of people accepting the restrictions and following them "voluntarily" mixed with the fear that once in a blue moon you might get caught and that might be today.

[Lootman]

The Bobby who acted as their "minder" told me that average speeds had dropped by 10%. However, my own observations based on frequent walks and back to Waitrose on that road suggested that there was a very high lack of compliance (almost 100%) and that many people were still doing of the order of 35-40 mph.

If a 20 limit is imposed on a road where the natural speed is double that, then the limit will routinely be ignored. In fact if you drive at 20 on a road like that you will be a obstruction and a hazard to other traffic. So in practice it is impossible to drive that slow unless conditions warrant it.

In fact in almost any situation, I notice that if I drive at the limit then vehicles routinely overtake me and there is a queue of vehicles behind me. I end up feeling like a menace to others.

The "twenty is plenty" mob do not seem to grasp this.

[Arborbridge]

The Bobby who acted as their "minder" told me that average speeds had dropped by 10%. However, my own observations based on frequent walks and back to Waitrose on that road suggested that there was a very high lack of compliance (almost 100%) and that many people were still doing of the order of 35-40 mph.

If a 20 limit is imposed on a road where the natural speed is double that, then the limit will routinely be ignored. In fact if you drive at 20 on a road like that you will be a obstruction and a hazard to other traffic. So in practice it is impossible to drive that slow unless conditions warrant it.

In fact in almost any situation, I notice that if I drive at the limit then vehicles routinely overtake me and there is a queue of vehicles behind me. I end up feeling like a menace to others.

The "twenty is plenty" mob do not seem to grasp this.

People who cannot keep at or reasonably near the speed limit are the menace, you and the people obeying the limit are no menace at all so don't be pressured into going faster because of law breakers. The dynamic hazard comes entirely from those flouting the law and they should be punished, in my view. I resent being pressured into breaking the law myself, just because someone behind thinks I should.
Having said that, I find it is (contrary to a remark by richlist) quite hard NOT to exceed 20 accidentally in a modern car, espescially on a roll downhill. On any road, I will keep to the speed limit, whether 20 or 30 using my cruise control if necessary. As for the people behind, it's their lookout whether they choose to drive recklessly or follow my lead - I have no sympathy for road yobs. If I get a queue of seven cars behind me, what of it - one could argue I am fulfilling a public duty by slowing them down.

On your point about the "natural" speed, there is no such thing. Even on the stretch I mention, although one could easily do 50 for a while, and there's a golf course on one side which makes it seem safe, on the other side there are roads coming in and housing, and there are pedestrians (like me) walking along the pavement. I used to get really peed off at yobs charging along and forgetting that this is making walking both less pleasant and more hazardous.

What I do find puzzling is the case near me where a 40mph limit turns to 50 just on the stretch where there is a double bend which obliges one to slow down! How they decided on that placement is a cause of wonder.

Arb.

[Ma1co1m]

The answer to your question about how well it will be enforced is "it depends". I was quite surprised recently to read that the 20mph estate road that's 30 seconds walk from my house was number 2 in the list of most speeding tickets issued in my council area in 2020 ( as, no doubt, were all of those caught ).

ma1co1m

[AF62]

If a 20 limit is imposed on a road where the natural speed is double that, then the limit will routinely be ignored. In fact if you drive at 20 on a road like that you will be a obstruction and a hazard to other traffic. So in practice it is impossible to drive that slow unless conditions warrant it.

In fact in almost any situation, I notice that if I drive at the limit then vehicles routinely overtake me and there is a queue of vehicles behind me. I end up feeling like a menace to others.

The "twenty is plenty" mob do not seem to grasp this.

A few years back my commute took me through a village with a 30mph limit where the council had installed speed cushions. The council had deliberately installed humps that were on the absolute limit of being legal to encourage the slowest speeds possible (the marvellous FOI Act revealed this).

As I had a car I cared about, this meant that taking the winding mile long route through the village at 15mph in second gear and slowing down further as you approached each hump if you were not going to do any damage.

Unsurprisingly the SUV drivers who inhabited this bit of countryside and the 'white van man' delivery drivers did not appreciate this as their wider track spanned the cushions so they didn't understand the problem. Getting frustrated they usually ended up overtaking on blind bends, and then zooming off into the distance to make up for lost time..

The council didn't see the irony that their actions had made the road less safe.

More recently I had occasion to drive into London and around Regents Park the whole area is a 20mph zone. So not knowing the area and what enforcement there is, I simply set the speed limiter on my car to 20mph and kept my foot on the floor. A lot of cars and vans overtook, and not in the safest way.

[richlist]

I always obey the 20mph limits.
It's not that difficult, you just ease your foot off the accelerator until the speed drops to 20mph or less.

At 20mph anyone hit by a car has a much better chance of survival.

That was not the question. But according to the post above, 85% of drivers don't. And with what chance of being caught?

You posted that nobody obeys those speed limits.
I corrected you to show that some of us do.

[Lanark]

In 2016, Bath and North East Somerset Council spent over £870,000 rolling out 20 mph limits across 13 zones. Only 12 months later, Council chiefs had to admit that the areas had experienced a rise in the number of deaths and serious injuries amongst pedestrians and cyclists in particular, in the districts where the reduced limits were in force. However, the Council had refused to reverse the schemes because the cost of doing so was too expensive!
https://www.mooneerams.com/blog/does-re ... accidents/

The whole thing a is great example of officials not understanding statistics:

> accidents at lower speeds have lower fatality rate.
> thus we reduce the speed limit and we will get fewer accidents.

Not so fast, human behaviour is much more complex, not everyone follows the rules and the biggest risk for accidents is not speed but differences in speed.
A bunch of cars all doing 60 is safer than some doing 60 and some doing 30 and that in turn is safer than some doing 40 and some 10.

My theory is that driving at 20 mph make it much easier (and more tempting) to check your Facebook page while driving along.

[AF62]

Not so fast, human behaviour is much more complex, not everyone follows the rules and the biggest risk for accidents is not speed but differences in speed.
A bunch of cars all doing 60 is safer than some doing 60 and some doing 30 and that in turn is safer than some doing 40 and some 10.

Not always. Not related to 20mph limits, but near where I live there is a major A road which is a dual carriageway and so was a 70mph limit.

The issue is that there is a junction used by a dozen houses, both to cross the dual carriageway and to turn in and out. Aside from the crossing issue, the 'run out' of the junction is insufficient to allow drivers joining to build up speed.

The 'solution', rather than redesigning the 'run out' was to implement a 60mph limit enforced by average speed cameras.

Now in the past you had some traffic doing 70, some doing 60, some doing 80, etc. resulting in lots of gaps in the traffic for the people to pull out of the junction into. Sure you needed some confidence, but it was achievable.

Now you have a constant stream of traffic all doing exactly 60mph with no gaps; and the 'run out' of the junction is still insufficient to allow drivers joining to build up speed, so they sit there, and sit there, and then get fed up and pull out at 10mph in front of a truck doing 60.

[richlist]

The Bobby who acted as their "minder" told me that average speeds had dropped by 10%. However, my own observations based on frequent walks and back to Waitrose on that road suggested that there was a very high lack of compliance (almost 100%) and that many people were still doing of the order of 35-40 mph.

If a 20 limit is imposed on a road where the natural speed is double that, then the limit will routinely be ignored. In fact if you drive at 20 on a road like that you will be a obstruction and a hazard to other traffic. So in practice it is impossible to drive that slow unless conditions warrant it.

In fact in almost any situation, I notice that if I drive at the limit then vehicles routinely overtake me and there is a queue of vehicles behind me. I end up feeling like a menace to others.

The "twenty is plenty" mob do not seem to grasp this.

Having said that, I find it is (contrary to a remark by richlist) quite hard NOT to exceed 20 accidentally in a modern car, espescially on a roll downhill.

Arb.

There are cars available that have a better cruise control system.
I have a Mercedes that has cruise control that maintains the set speed, even downhill.

[airbus330]

I my neck of the woods, I'm quite lucky in that 20 zones or limits are rare and where they are in action they are generally respected. I have never seen any enforcement in a 20 area, but some particularly vicious speed humps make it a no brainer anyway. The other end of the spectrum is London which has a lot of them and enforcement cameras, but seems to me to be largely ignored, especially by cyclists who often undertake the motor vehicles!
These two extremes seem to illustrate the problem of letting local authorities do their own thing, rather than having a national policy. It served us well enough for years and I can understand the old rules for speeds. If I do a trip from one end of Wales to the other I'm faced with constant changes of limit, often illogical, distracting changes, which after a while I tend to ignore and drive to the road conditions. Not legally in many cases, but I'd rather concentrate on the road than the signage. But, you can be sure, if I go through a village, I'll be doing 30 even if it says 40 and passing a school even slower still. Bad law making (lord knows there is enough of that in 21st century Britain, breeds contempt for the law. Nothing new in that.

[Mike4]

If a 20 limit is imposed on a road where the natural speed is double that, then the limit will routinely be ignored. In fact if you drive at 20 on a road like that you will be a obstruction and a hazard to other traffic. So in practice it is impossible to drive that slow unless conditions warrant it.

In fact in almost any situation, I notice that if I drive at the limit then vehicles routinely overtake me and there is a queue of vehicles behind me. I end up feeling like a menace to others.

The "twenty is plenty" mob do not seem to grasp this.

Having said that, I find it is (contrary to a remark by richlist) quite hard NOT to exceed 20 accidentally in a modern car, espescially on a roll downhill.

Arb.

There are cars available that have a better cruise control system.
I have a Mercedes that has cruise control that maintains the set speed, even downhill.

Interesting. My Mercedes does this too but the cruise doesn't work under 20mph. And it's real difficult to engage it bang on 20mph.

[Arborbridge]

Having said that, I find it is (contrary to a remark by richlist) quite hard NOT to exceed 20 accidentally in a modern car, espescially on a roll downhill.

Arb.

There are cars available that have a better cruise control system.
I have a Mercedes that has cruise control that maintains the set speed, even downhill.

Interesting. My Mercedes does this too but the cruise doesn't work under 20mph. And it's real difficult to engage it bang on 20mph.

Mine will go on at 20mph, but in fact I use it at 21. Why? Because I've tested it against several speed cameras and believe it undereads by 1pmh, so I've happy to up the apparent speed to appease the road rage mob.

If I don't use the control, there's no way I could keep the speed down for certain. BTW, I forgot to engage it once coming out of my turning on to the road I'm talking about and without thinking my speed went rapidly up to 25 or more but even so it didn't trigger the speed camera. So, naturally being curious about this, I did a couple or dummy runs at the camera, set supposedly at 20mph - it does not trigger until until 26-27 mph on my speedo. So even the authorities find they have to appease the road hogs. No wonder people are still charging down this road, which includes overtaking unsafely.

Arb.

[swill453]

If I don't use the control, there's no way I could keep the speed down for certain. BTW, I forgot to engage it once coming out of my turning on to the road I'm talking about and without thinking my speed went rapidly up to 25 or more but even so it didn't trigger the speed camera. So, naturally being curious about this, I did a couple or dummy runs at the camera, set supposedly at 20mph - it does not trigger until until 26-27 mph on my speedo. So even the authorities find they have to appease the road hogs. No wonder people are still charging down this road, which includes overtaking unsafely.

I'm puzzled. Are you talking about these displays that tell you your own speed, or tell you to slow down? They're not cameras, and they're not calibrated to the same level as cameras.

Scott.