Dear Richard Davies

The main issue is that speed humps work: they save lives. That is not in dispute. The evidence is overwhelming. Please do not lose sight of that as you explore other more trivial effects of speed humps.

The Mayor has rightly set what he sees as tough road safety targets. I'd like to see an approach her similar to Sweden's "Vision Zero" which targets zero road deaths. As a patron of RoadPeace, our Mayor should perhaps set such an exemplary target?

For the time being, road humps are our most effective tool against urban speeding which causes over 1000 deaths per year in UK. Until we have more effective tools, such as satellite controlled speed limiters in all cars (the technology is currently being tested) speed humps must remain in place, even though as a cyclist I find them an uncomfortable nuisance! In answer to your specific questions.

No doubt you are asking them. Note that speed humps = fewer call outs for the emergency services! Note also that slower traffic = safer streets which can induce people to walk or cycle more and thus help to improve general health and fitness levels. Underlying principle: prevention is better than cure.

No they do not - they are inanimate and stationary objects. This point is not made out of pure pedantry, it is made because the question indicates woolly thinking. If any damage to property arises, its cause is the car or lorry going over the hump, probably too fast. Therefore any resultant costs should be borne by the motorists who are doing the damage. This would be another external cost of motoring that should be internalised, i.e. make the polluter pay.

Not if they are set the right distance apart to encourage steady smooth driving at 20mph. Note that car manufacturers are likely to become interested in producing vehicles with small engines and appropriate gearing for slow urban driving, once 20mph becomes the norm.

No: slower more constant speeds improve traffic flows, and there are fewer crashes which in themselves are a frequent cause of congestion.

Likely: this is a strong case for making most of London a 20mph zone, as we are delighted to note, the Mayor has pledged. This will be in his next manifesto, he said, at a cycling conference in London on May 10th2003.

No. See pedantic point above. Car drivers may damage their cars by driving over speed humps too fast, much in the same way as they are likely to damage their cars by driving them into other cars, brick walls, etc...

We need a combination of all these measures, depending on type of road, it is a matter of horses for courses. I favour all of the above. Speed limiters are on their way in, but slowly, and there will be huge resistance from the mighty motor lobby, which will intimidate most politicians. Thankfully, our Mayor is not most politicians. He should do all he can to lobby for the introduction of speed limiters on all cars sooner rather than later. This technology will save thousands of lives every year. Once cars no longer have the ability to exceed speed limits, softer transport modes will become much more attractive alternatives, there will be massive modal shift, and we will be able to design our streets for people instead of for cars.

The evidence shows that speed humps cut deaths and injuries by up to 67%for children. They work. Barnet's policy of removing them is scandalous, and should be legally challenged.

Yours sincerely, Richard Evans, Merton Cycling Campaign http://www.mertoncyclists.org.uk