APPARENTLY, 84 per cent of people want to save the green belt and keep if safe from urban sprawl. Can it be true? Can 16 per cent of the country really believe that it’s right to pave over our pleasant land? I thought it was just me who reckoned the green belt was a colossally misguided scheme to inflate house prices, cripple the economy and do absolutely nil for the environment.

Try telling people that you think the green belt should be scrapped — worse still, that you think the entire system of Government planning should be done away with — and you won’t win many friends. To argue against the belt, which surrounds London, Birmingham and other big cities and which celebrates its 50th anniversary this month, is to most people like calling for clean drinking water to be abolished, or campaigning to bring back witch-ducking.

Never mind that nobody seems to know what it looks like, or whether any of it is very nice. I’ve lived in London all my life and I’ve never hear anyone saying that they’re off to spend a weekend in the green belt, what with it being so close by and everything. Maybe the BBC’s new hit series Coast only narrowly beat a rival show called Disused Gravel Pits in Tilbury, but I doubt it.

The point is, for every Chiltern hill or slope of the North Downs that the scheme protects, massive chunks of land that are downright foul are kept at bay from the potentially cheering extension of the suburbs.

Green belts do not create parkland within easy reach. Their real point is to prevent sprawl — although why London or Newcastle should be equally stopped from sprawling is hard to explain: they can’t both be the ideal size, surely. Green belts increase pollution by encouraging development farther from the city, so adding to the number of miles commuters have to drive. Mark Pennington, an economics lecturer at Queen Mary College, points out that the new towns will often end up being built on much more environmentally valuable land than the belt itself. All that green belts do is to halt city growth, regardless of the economic benefits of new construction.

Ah. That word — economic — gets you in trouble. The complaint comes that letting the market run loose would cause havoc, because “land is a finite resource”: once we’ve paved over Britain, we can never get it back. But economics is all about managing scarce resources — oil, labour or anything else. And economists will tell you that to manage resources effectively, you need information about their relative values. There is a word for such information: prices. Some of the green belt is lovely, some of it is awful — but greenbelt policy sucks because by shutting down the system of prices it fails to distinguish one from the other. If green belt land were traded freely, and could be developed without constraint, the magic of the price mechanism would get to work. Beautiful land would come at a higher price than ugly land, and developers would be guided to build in cheaper areas.

But alarm has been the sole response to Government plans, unveiled last month, to make planning more responsive to housing demand. Frankly, it would be hard to dream up a system less responsive to housing demand than the current planning laws.

Anyone who has tried to get a building project approved will know how slow, expensive and often corrupt the set-up is. Planning is the legacy of the postwar Town and Country Planning Act, which tried to do to home building what the Attlee Government was also trying with coal, steel and other industries: control them from above. But, unlike those dinosaurs, planning has never been reformed, and it remains more like a vast, sclerotic, nationalised industry than anything else. Even John Prescott has been unable to break the logjam. Despite his threatening year after year to swamp the Thames Gateway and Bedfordshire with Barratt homes, the big build remains stubbornly unbuilt.

People think that if you got rid of government planning you would have anarchy. But that’s not how things work in other parts of the economy. Prices allow a much more sophisticated level of co-ordination, in which demand for houses, offices and open spaces are all stirred into the mix. Do you live in an area with lots of attractive Victorian homes, where buildings that are out of character would damage the appeal? So club together with your neighbours, sign a restrictive covenant that bans everyone in the group from making changes, and watch the market response. Everyone in the group should see their house price rise, because each house becomes more valuable in an area guaranteed to stay attractive.

Having said all of that, I’m not against planning. Planning a town, working out how to mix homes, infrastructure and open spaces, is difficult, but not impossible. The problem is that there is only ever one planner — the Government. To scrap state planning would bring about a renaissance in a forgotten world from a century ago, when private corporations bought land speculatively and created garden cities and suburbs, many with restrictive covenants to keep them from decline. Competition between planners — something the current system lacks — drove up standards of design.

Thanks to the efforts of private planners, we now have picturesque suburbs and towns such as Highgate, Summertown and Letchworth. It could happen again. Tesco towns? They’d certainly beat a weekend for two in a gravel pit.

Gabriel Rozenberg is economics reporter for The Times

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