They appear like molehills. They madden drivers. But they save lives and all over Britain people are demanding - and getting - more of them. David Nicholson-Lord reports on the ...
Four striking black-and-white photographs decorate the Leicester offices of the community arts consultancy Soft Touch. They were taken around 40 years ago: in one, a girl skips down a street; in another, a boy, surrounded by smaller siblings, pushes a pram. The streets are empty apart from people; the only car in view is a toy one, being pedalled furiously across the cobbles by a toddler.

The photographs are of Salford, but they could have been taken in any British town or city in the Fifties. Since then, a tidal wave of traffic has engulfed such scenes, driving toddlers, prams and toy cars indoors and killing off many of those with the temerity to stay outside.

Soft Touch uses these photographs to show what cities were once like and, more important, how they might be again. Five years ago that might have seemed little more than idle fantasy; now, thanks in large part to grassroots protest, the tide of traffic is being turned back.

The chief instrument of this reversal is the road hump, that reptilian bulge in the tarmac also known as a sleeping policeman. No one knows exactly how many road humps there are in Britain, but their numbers run into tens, possibly hundreds, of thousands. A decade ago you could probably have counted the number of humps on public roads in the hundreds.

This explosion in numbers, and the dramatic metamorphosis of flat urban roadscapes into hummocks and hillocks, carries an important message about our relationship with the car. Since the 18th century, the aim of planners and civil engineers has been to make roads straighter, flatter and quicker. By building a hump, we are doing the opposite - and, by implication, questioning the right of motorists to drive where they want at the speed they please.

All over Britain, people are clamouring for "traffic calming": the slowing and removal of traffic from residential areas. Lynn Sloman, of the leading transport and environment pressure group Transport 2000, says there has been a "huge groundswell" of agitation. In cities such as Sheffield, campaign groups, many led by women, have blocked roads, held up traffic and erected their own speed limit signs. Last year, only three years after the first official 20mph zones were introduced in the UK, the 100th was opened, with the enthusiastic backing of the notoriously car-friendly Department of Transport.

As well as humps, a 20mph zone may have "pinch points" - posts that narrow the road - chicanes, gates or a combination of these. The Transport and Road Research Laboratory says that traffic calming is now "almost universal" - and yet it can't be because there is still a vast unmet demand.

Sheffield, for example, was one of the first authorities to introduce a 20mph zone in January 1991 and now has three, covering perhaps 90 streets; another 15 streets have been calmed without the 20mph speed limit. But residents in a further 400 streets are asking for humps and have been told they can't have them yet. Rebecca Higman, of the local branch of Friends of the Earth, says Sheffield City Council has been "overwhelmed" by demand; Kevin Platt, its road safety engineer, is fed up with writing letters saying there is no money for them.

British attitudes to traffic calming are riven with paradox. Our belated conversion, in the late Eighties, had much to do with the Government's realisation that road humps save money - specifically, the £40,000 cost of a typical accident (£863,000 for a death). Local authorities compete for a slice of the DoT's £50m road safety fund on the basis of cost-benefit analysis: will it cost less to stop people being killed than it does to clear up the mess? Many schemes achieve a remarkable, if macabre, 30-40 per cent return on investment. Yet hundreds more fail to qualify because there are not enough "dead bodies". In fact, says MrPlatt, "danger and accidents are often opposites". Accidents happen when people feel safe: where the dangers are obvious, pedestrians get off the streets.

Lynn Sloman believes that agitation in favour of traffic calming is a local echo of the national battle against the car and the roads programme. "We have heard a lot about the negative effects of roads, but until now people have just thought there was nothing they could do. Now they are saying maybe there is. There is beginning to be a recognition that streets are not only for cars. They are for people, too."

"Streets for people" sounds like a slogan, but in a peculiarly precise way it describes reality. Since those photographs of Salford were taken, Britain's population has increased by a tenth, but its vehicle population has grown five-fold. The result is that people not in cars - walkers, cyclists, children, the elderly - have been frightened off the streets. In 1971, 90 per cent of junior school children walked to school; two decades later this had dropped to 9 per cent. The Government's much-vaunted "success" in reducing traffic deaths is probably due in large part to the fact that cars nowadays simply have far fewer unprotected humans to hit.

The costs in children's health and independence, in parental time spent ferrying them about, in the freedom of the elderly and the conviviality of neighbourhoods, all have been enormous. In Leicester, where they are attempting to rescue streets for play and create "safe trails" for children to walk to school, Vince Attwood, of Soft Touch, speaks of the difficulty of persuading parents that children should be allowed to play in the street. Hence the pictures of Salford. "We want to show them - to remind them - what the streets were like when they were kids. They may have forgotten it, but these were the sorts of places where they used to play."

With the creeping domination of the car came a new ethic. Read through most modern research on traffic accidents and you are struck, first, by the pervasive concept of pedestrian "guilt" and, second, by the sheer ordinariness of pedestrian road deaths, particularly among the young: one survey found that a third of all casualties under the age of nine are killed directly outside their own homes.

Nowhere has this new psychology of blame been more evident than in our acceptance of the culture of speed: nearly a quarter of motorists - about 5 million - see nothing wrong in breaking the speed limit in towns (the figure is almost double for motorways). Yet even if you are sticking to the 30mph limit when you hit a pedestrian, there is a 37 per cent chance you will kill him. At 45mph, this probability rises to 83 per cent. At 20mph it drops to 5 per cent.

A 100mm hump - the tallest now permissible - can reduce vehicle speeds down to 13mph. Pound for pound - an asphalt sleeping policeman costs about £500 - it is probably the most effective speed reduction measure in use. In 20mph zones around the country, casualties are down by 70 per cent. Among children the figure is even higher - 80 per cent. If every street in Britain had a 20mph zone, something like 25,000 children would be spared death or injury every year.

A lot of people, however, do not like them. Humps, it is said, wreck suspensions, increase pollution - some drivers tend to accelerate then brake between them - slow ambulances and fire engines, and give bus passengers a bumpy ride.

In some areas - Brighton, Hertfordshire, Kent - traffic calming has run into opposition. In the Northamptonshire village of Croughton, a scheme had to be taken out because locals claimed the slatted wooden entrance gates made it look like a safari park. The county council has declared a moratorium, at least in rural areas.

Some of the criticisms may be justified. Calming schemes tend to be designed by traffic engineers, people not known for their aesthetic skills. Carmen Hass-Klau, a leading transport consultant, says that traffic-calming in Britain has been distinguished by its "excruciating ugliness". And the hump, per se, is a blunt instrument. Hence it is being redesigned, its shape changed, to meet different circumstances: the "speed cushion", for instance, is a narrow hump that can be straddled by wide-bodied buses or fire engines. But the complaints also signify a less appetising phenomenon: the revolt of the roadhog.

When Soft Touch set up street stalls in Leicester to gauge public opinion on traffic calming, there were loud noises of complaint. Then they analysed the questionnaires from the less voluble majority and found that people were "wildly in favour". According to Vince Attwood, "the people making the noise were a vocal minority of mainly middle-aged men with cars. They wanted the right to drive their cars without damaging them. They still have that right - all the traffic calming does is reduce their ability to drive so quickly." Many traffic experts also include young males - and, increasingly, young women - in that vocal minority.

By common consent, Britain is about 15 years behind the rest of Europe in car restraint: in Bremen and Amsterdam they are already talking of car-free cities. But don't underestimate the sleeping policeman. Thousands of people are starting to question what Clare Draffin, one of the Sheffield traffic calming campaigners, calls "the idea that people who live somewhere else have the licence to drive past your home and completely limit the life you lead - to turn it into a prison." In its small and sometimes ugly way, the road hump is a revolution in the making.