20mph: wisdom or waste of money?


By - Wednesday 1st February, 2017

The dispute rumbles on, but are speed limits on residential roads the right focus for safety efforts?


Sometimes you just can’t win. My previous article on the proposal for a 20mph limit, questioning its efficacy in the first area identified in North Croydon, resulted in more comments than anything that I have written in the Citizen. They were mostly negative.

Yet when I spoke from the floor at a recent meeting in Coulsdon called to protest the imposition in the south of the borough, I was not exactly applauded. Perhaps I shouldn’t have started with the line that if you’re going to get hit by a car I’d go for one travelling at 20 rather than one travelling at 30mph.

It seems that you must be for or against. ‘It depends’ is no-man’s-land, and to tread there is to be assumed a scoundrel. But that is where most decisions are. Having accepted that cars are part of our lives, the decision is how best to reduce their adverse impact.

‘It depends’ means in this case that there are roads where a properly supported 20mph speed limit makes sense, and others where it doesn’t. ‘Properly supported’ means more than just putting up speed limit signs, which is all that the council plans to do.

Data shows that deaths and serious injuries haven’t been occurring on the roads whose speed limit is changing

If you live in one of the affected areas, you should by now have received a leaflet from the council explaining the proposal. You are being ‘consulted’, but not like people in the previous two areas were. The fairness and democracy of that has been dealt with elsewhere.

In your leaflet you will see that A and B roads have already been excluded, so will remain as 30mph roads. The rest, it is proposed, will become 20mph zones. This may seem perverse when data from the Crashmap website shows that deaths and serious injuries over the last fifteen years have occurred almost exclusively on the roads whose speed limit is not being changed.

Before digging into the detail, let’s ponder the question that we are being asked. In the first two zones the residents were surveyed as to whether they did or did not want the 20mph zoning as outlined. This passed narrowly. They were then consulted, one presumes primarily on how it would be implemented. The principle was by then agreed, but fine-tuning modifications might be made.

There are clearly streets where a 20mph limit is entirely sensible

We in the rest of Croydon are only being ‘consulted’ without a survey. So are we being asked both whether and how, or just how? The realist in me says probably neither but let’s be charitable, let’s assume both.

Starting close to home, I live in a cul-de-sac. I doubt that anyone has ever gone more than 20mph in the decades that the street has existed. If they did, they would be sufficiently crazy that planting two street signs at the end of the road is unlikely to stop them. For streets like mine it does not matter whether the limit is 20 or 30, it will make not one jot of difference to the traffic speed. I am happy with either, but concerned at the expense of the ineffective street furniture.

Many of the residential streets in the neighbourhood are similar, but some are not. There are cut-throughs and streets close to schools. All have speed bumps already in place. Thus fortified, these are clearly streets where a 20mph limit is entirely sensible.

Parked cars turn a wide road with good visibility into something entirely different

This leaves a few streets where speeds might routinely exceed 20mph. Are they safe, and if not will imposing a 20mph limit make them safer?

One is Croham Manor Road, a wide street where both cars and pedestrians are few and where few cars are ever parked. Except, that is, at the northern end when there is a rugby game at the Old Whitgiftians. Then it becomes a much more dangerous place. Parked cars turn a wide road with good visibility into something entirely different.

In the absence of the council’s proposal, I would be inclined to put speed bumps or parking restrictions at the dangerous end. Given the proposal, this is a candidate for a 20mph limit, but one where I expect routine law-breaking at the southern end.

I can see better ways to improve safety than to impose a blanket 20mph limit

Another is the Carlton Road/Mayfield road section of the 403 bus route. (If you want a quick way to look for anomalies look for the sections of bus routes that do not follow the A and B roads.) This road has some traffic, and is one that, for me, is safe at 30mph. Safety that would be improved by some limited additional parking restrictions.

So if I were looking to improve safety, I can see better ways than to impose a blanket 20mph limit. But given my expectation that this will be imposed anyway, then the Carlton Road/Mayfield Road section is my suggested modification.

In the meantime, I’m taking a mental note to watch out for future speed traps on the Croham Manor Road.

Robert Ward

Robert Ward

Engineer and project manager specialised in helping businesses make better strategic decisions and improve safety, quality and effectiveness. Conservative Party Councillor representing Selsdon and Addington Village on Croydon Council. He tweets as @moguloilman.

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  • Ian Marvin

    It’s a start and if nothing else it’s bringing attention to the issue. We have a head start here in Thornton Heath and already there are discussions over how danger spots can be improved. It never occurred to me to write an article about it but perhaps I should. Incidentally Grange Road is an A road where the 20 limit has been added. It didn’t prevent a car overturning and burning out last month though.

    • Robert Ward

      Do go ahead and write an article Ian. Citizen readers are always interested about what is going on in Croydon.

      Regarding the burned out car, crazy drivers will likely not be stopped by a sign with a 20 on it rather than a 30. Speed bumps might help, but we should be designing for the vast majority not the mercifully rare reckless speeder.

      • Ian Marvin

        I’m having a rare moment where I don’t owe the Citizen an article I’ve promised but I’ll write something when the time is right.

  • blath8@googlemail.com

    Interesting that the speed limit is not being lowered on the roads where more accidents occur, particularly as issues regarding making a road one-way for safety reasons won’t be considered until fatalities occur (which used to be a certain number within a given period). It would seem eminently sensible to consider the situation/conditions on each road before simply reducing the speed limit en masse and adding to the street clutter (aren’t the Council trying to reduce that? Removal of safety barriers on dual carriageway anyone?) which is useless without some sort of policing. Would be nice if pedestrians took a little more care too – as a cyclist, they are more dangerous to me than the traffic!

  • Anne Giles

    I am very much in favour of a 20 mph speed limit in the winding streets of Selsdon Vale. Quite often it is difficult to drive any faster anyway. With cars parked on both sides of each street and being tailgated by impatient drivers and buses that come zooming round and forcing car drivers on to the pavements, 30mph is not safe at all.

  • Michael Swadling

    The whole 20mph debate should also consider the impact of reduced speed limits. The opportunity cost of the time of 30 people spent on the bus taking longer to get to their destination, the extra vans and lorries needed to make the same number of deliveries etc. There is also the cost of implementing this change, could more lives be saved putting the funding into social care? Could more lives be improved with this being used as further funding to our schools? We can make roads safer at 20mph but at what impact? If the only side of the debate is slower=safer then why not make the roads 10mph or 5mph. My main concern with this has been the lack of a vote offered in the current consultation. That vote would allow a further debate. I believe it could call out that greatly enhanced measures in accident hot spots or high risk areas (for instance around schools) would be both more effective and cheaper but also without the level of opportunity cost of a blanket change.

  • L Richard Patrick

    I think when it’s roads on estates, yes that is good, as the roads are narrow, cars are parked everywhere, so that is understandable. Other roads, such as Bridle Road, Shirley Church Road, are usually very quite, so really stupid to have it here. These roads should be only 20mph when it’s school times, so 3-4 pm, then it should revert back to 30mph as it just causes more congestion and annoyance. If this is an attempt to stop people speeding, it’s very silly, as people who speed, don’t care if it’s meant to be 20, 30, 40, they’ll do what they like, so as per usual it’s the law abiding citizens who end up suffering! Almost everywhere in Croydon is 20mph, guess the labour run croydon council have got to find ways to waste money again. They just did all the pathways near where I live, they were fine as they were, pity they didn’t do all the pot holes that are in the roads, such as Laurel Crescent, they never cease to amaze me!