Tonbridge to implement town-wide 20mph speed limit to encourage more cycling

Enforcement definitely needed.  In the short term this includes Community Speedwatch, which is effective.  In the longer term, mandatory ISA and black boxes in new cars from 2022 will mean greater compliance.  It's even more reason to implement lower speed limits now, so that ISA helps people to drive at an appropriate speed where people and motor vehicles mix.      

Adrian Berendt wrote:

Enforcement definitely needed.  In the short term this includes Community Speedwatch, which is effective.  In the longer term, mandatory ISA and black boxes in new cars from 2022 will mean greater compliance.  It's even more reason to implement lower speed limits now, so that ISA helps people to drive at an appropriate speed where people and motor vehicles mix.      

Great, so now we'll have to listen to "Ride on Time" blaring out of all the car windows. Personally, I prefer the original Love Sensation.

Take care with the RoSPA report - there are lots of errors.  I have pointed these out to RoSPA on more than one occasion and they produced a new briefing in February 2020, but it's still wrong 

E.g., it quotes an old report highlighting the  fatality risk of "2.5% at 20mph and 20% at 30mph (8x)", but the latest studies generally quote 10% and 50% (5x).  Either way, the risk of a pedestrian dying in a collision at 30mph is a multiple of the risk at 20mph. 

It's also completely wrong about the difference between 20mph speed limits and 20ph zones.  In practice, there's almost no difference these days

The passage you quote refers to the 1999 law change.  The current consensus from public health and road safety organisations is that 20mph is the right speed where people and motor vehicles mix (e.g. the Stockholm Declaration signed by the UK Government, amongst other in February 2020).  The current speed on a particular road doesn't determine the appropriate speed limit, but rather shows the amount of intervention needed to bring speeds down to appropriate levels.

The RoSPA statement about which streets should be 20mph does NOT mean excluding major through routes.  The DfT guidance is that 20mph should be implemented on residential streets, town and village centres etc AND on major roads, where there are (or could be) lots of pedestrians and cyclists.

The quote from the DfT guidance is:

1) major streets where there are – or could be - significant numbers of journeys on foot, and/or where pedal cycle movements are an important consideration, and this outweighs the disadvantage of longer journey times for motorised traffic.

This is in addition to:

2) residential streets in cities, towns and villages, particularly where the streets are being used by people on foot and on bicycles, there is community support and the characteristics of the street are suitable.

Hope that helps...

Luckily the A21 bypasses Tonbridge High St nowadays, so that is a good start

You'd need to ask the local police about that. The good news is that even without enforcement, experience of other towns shows that lowering the speed limit does reduce traffic speeds.

If you Google 'Vehicle Speed Compliance Statistics, Great Britain: 2017' you will find UK.Gov statistics showng speed limit compliance is poor.

Maybe they should go for a 10mph limit then ( to achieve compliance to 20mph )  

Still 10mph over a 20 limit is way better than 10mph over a 30 limit.
It would be great if people were penalised more regularly for speeding as people seem incapable of policing themselves. Is it selfishness or stupidity?

Small caveat.  For 20mph, as there are only 9 sites, none of which are typical of 20mph streets, the data is not very reliable. Places that have introduced 20mph speed limits do see lower speeds and the reductions are greatest on roads which were previously faster.  E.g. where average speeds were previously near 20mph, speeds reduce by 1 to 2 mph - not huge, but still significant.  On faster roads average speeds fall more.  E.g. in Bristol and Portsmouth, they fell by more 6-7mph        

The scheme is not costing Tonbridge council tax payers anything.  It's being funded from the Government's Emergency Active Travel Fund.  Although speed limits are policed, reduced funding for police forces has meant less enforcement, and more funding for enforcement is needed.    Having said that, even without active enforcement, average speed do reduce when 20mph speed limits are introduced.