Road Safety News

20 could soon be plenty for Plymouth drivers

Monday 14th September 2015

The speed limit for nearly 80 roads in Plymouth could be reduced to 20mph as part of Plymouth City Council’s long-term plans to improve road safety.

The council has proposed the restrictions as part of a scheme to reduce 30mph limits in residential roads where possible. 
The proposals also include other measures such as speed cushions, with the aim of forcing drivers to stick to the new limits.
Cllr Brian Vincent, cabinet member for streetscene at Plymouth City Council said: “The aim is to reduce the number and severity of road casualties among school pupils in the city, reduce speed in residential areas, and address local concerns that have been raised about traffic and transport issues.
“This is part of a wider scheme that has been in place since 2010 and we have already carried out similar work in other areas in the city. We have already agreed a programme to introduce 20mph limits in residential roads wherever practical to do so, especially near schools, and with appropriate signage.”
According to a report in the Plymouth Herald, the limits will be enforced by Devon and Cornwall Police and have polarised opinion, with fears from the public that the new restrictions will be difficult to enforce.
A Devon and Cornwall Police spokesman told the Plymouth Herald: “If action to curtail speed is to be considered within 20mph limits, a number of options can be considered.
“This may include high visibility patrols in the locality, speed limit indicator devices flashing the limit to traffic, letter drops in the area and Community Speed Watch.
“Enforcement through prosecution is a final resort and where evidence is available of wilful violations by specific offenders at known times of the day, enforcement action should be targeted at those identified times and offending motorists.”
Photo copyright Derek Harper and licensed for reuse under this Creative Commons Licence.


Comment on this story
Report a reader comment

What's your view - comment on this story:

I confirm that I have read and accept the moderation policy and house rules relating to comments posted on this website.
Your comment:
Your name and location:
Your email:

Portsmouth's results showed that average speeds fell by only 1mph or so, but by greater margins on some roads. Though not mentioned (of course) this means that speeds must also have risen on other roads.....

It is important to understand that (like walking along the edge of a cliff) the graph of risk against speed (or distance from cliff edge) is not linear. Reducing speeds below those thought to be safe is likely to cut accidents by smaller margins than increasing speeds above those previously thought safe will increase them.
Idris Francis Fight Back With Facts Petersfield

Agree (2) | Disagree (3)


So, how could you find two communities that are identical in street topology, car usage, cultural consensus, political make up, campaigning profiles, etc and then tell one to stop campaigning or talking about the benefits of reduced speed and limits whilst allowing the other to do engagement which is limited only to one site? How would you have police enforcement in one but not the other? How would you have media reports on censored in the other? How would you include areas big enough for the results to have any statistical significance?

These are all difficult question to answer for any initiative based on community consensus and engagement.
Rod King, 20's Plenty for Us

Agree (6) | Disagree (4)

"...and where evidence is available of wilful violations by specific offenders at known times of the day, enforcement action should be targeted at those identified times and offending motorists.” If the police are going to enforce these limits, then this is the best approach. The road shown in the photograph has the characteristics which make it likely to see excessive speeds on a regular basis and with enough hazards to make enforced speed reduction necessary and justified.
Hugh Jones, Cheshire

Agree (3) | Disagree (3)

Running scientific trials is easy:

1) decide what you want to measure
2) select suitable locations
3) randomly divide those locations into "test" and "control"

When we then compare results from our test and control sites, all factors are automatically accounted for with the exception of any cross-contamination (eg drivers diverting to other routes because of the intervention).

Is there any other field of safety engineering in which scientific trials would be straight-forward, yet those in charge refuse and argue against proper trials? Let's put aside opinions, theories, politics etc and start finding out what effect our interventions are actually having.
Dave Finney, Slough

Agree (8) | Disagree (6)

Very often it is the attempt to design a scientific trial that reveals more than the actual trial itself. In order to design a meaningful trial in any complex socio-technical system it is first neccessary to map all the variables in the system and then understand how those variables interact with each other. The very act of understanding the variables and their interactions is often enough to solve most of the problems within the system as it is the interactions that provide all of the system outcomes.

I would have thought that Mr King would welcome such a process as it could provide him with hard and irrefutable evidence for his claims. On the other hand it could also provide hard evidence that his claims are without any merit and that's probably why he is so against any form of trial.
Duncan MacKillop. No surprise - No accident.

Agree (9) | Disagree (5)

“Long term plans to improve road safety”. Pure politic.

Scientific trials need not be that scientific, merely a way of measuring before and after effects. By such a method (whatever it may be) we can discover just what speeds are being used along such chosen roads for a 20 limit, and thereby conclude whether any such limit is worthy of introduction at all, or whether it is another brain numbing exercise with the result of an accident where there may previously have been none. Judging from previous experiences the ‘results’ of 20 limits are shrouded in other elements, and have as yet to be shown to be of any use in reducing casualties. Currently it is hypothetical guesswork.

Speed humps and cushions create more negative impact than is useful. Greater brake wear, suspension wear, reduced response times in emergencies, vibrations, and extra pollution and noise – not to mention varying degrees of frustration which can lead to anger and a resultant lack of focus.
Derek Reynolds, Salop.

Agree (8) | Disagree (5)

The only practical trials which can be evidenced and will be of any use - and this applies to any new 20 limit - would be to measure the typical speeds of the fastest parts of some of the well-used roads and see by how much, if at all, they reduce. Comparing reductions achieved in the roads with speed cushions and those without would also, perhaps fairly obviously, be useful. I would suggest any enforcement be in the most well-used roads as word soon spreads in a community.
Hugh Jones, Cheshire

Agree (5) | Disagree (5)

Dave keeps on referring to his call for "scientific trials" within the context of 20mph limits as if it was something that was a) possible, and b) meaningful. I am afraid he fails to understand that wide-area 20mph limits are not about the mechanics of a driver reaction to a "sign on a stick" but are a developing social consensus that everyone when driving should be more aware of their impact on others they share the roads with. This cannot be "bottled" or applied to some for real and to others as a placebo. Whilst the endorsement of the establishment in setting a mandatory limit is important its the debate at street, town, county or country level that is where the real change of attitude is taking place.

And with over 20% of the population now living in places where that very process of consensus building is already happening then its difficult for anyone to not be involved. Even David in commenting on this article is part of the "spreading of the message" and the debate on why its important to share the roads in a better manner.
Rod King, 20's Plenty for Us

Agree (7) | Disagree (11)

Plymouth failed to introduce their previous 20mph within scientific trials, as have all other areas, so let's see them be the first to take an evidence-led approach.

I would call on objectors to support 20mph where this is done within scientific trials, and for supporters to insist upon scientific trials. Let's find common ground, and start really saving lives.
Dave Finney, Slough

Agree (9) | Disagree (7)