Ask whether it's time to re-think Britain's green belts, as we often do in these parts, and you're likely to get a mixed response. Part of your audience – the younger, more urban, more-likely-to-be-private-tenants part – will cheer you on. But a significant minority will call you all sorts of names, accuse you of being in the pocket of the construction industry, and probably at some point blame immigration.
Such is life. But since this debate isn't going to go away any time soon, we thought it might be worth injecting some figures into it. Let’s consider the Metropolitan Green Belt which has restricted London’s growth since 1938.
There are 33 boroughs in London, of which no fewer than 19 have at least some protected Green Belt land within them. This chart shows the size of those 19 by area (total bar length), and the proportion of each which is designated as Green Belt (the bit that's, well, green). We’ve taken our data from government figures, hosted here.
The first thing that you notice is that Bromley is enormous. At around 150 km2, it takes up very nearly a tenth of the entire capital, and it's larger than the eight smallest boroughs put together. (These are all in inner London, so don't feature on the graph.)
The next thing you notice is that more than half of that vast south eastern borough is green belt land (to be exact, 52 per cent of it).
In all, there’s around 77 km2 of Green Belt in Bromley: enough to swallow the City, Kensington, Islington, Hammersmith and Hackney whole, and still have room for most of Tower Hamlets. That's an area that houses nearly 1m people.
We're not seriously suggesting putting that many people in the green fields of Bromley. We're just pointing out that you could. Look:
Bromley isn't the only large outer borough that is, quite literally, half empty. Up in the north east, Havering is actually even roomier, with nearly 54 per cent of its land classified as Green Belt. Again, you can see this on the map, which shows that huge swathes of the borough are effectively empty.
To the west, Hillingdon is 43 per cent empty, while another four boroughs are more than a quarter Green Belt.
The point we're getting at here is that there is a lot of land classified as Green Belt even within London. In all, it's more than a fifth of the capital's land area (22.4 per cent).
As you might expect, the neighbouring areas are often even more in the grip of the Green Belt. Here's the same chart, but this time showing counties:
Now, “green belt" is actually at times a misleading label. The name evokes beautiful rolling fields, and some of this land will live up to that image. But it also includes quarries, and scrubland, and golf courses, and pony clubs. Some of this land is of value to the community; some of it isn't.
Nonetheless, there are those who see it as inviolable – who squeal at any suggestion we should re-label it as anything other than green belt, or develop it to meet London's housing needs. People who imagine that giving up even one blade of grass will turn the entirety of England into Houston within weeks.
But what it is that terrifies them so remains a complete mystery to me, because they are winning, hands down. Between 2007 and 2010, London lost approximately 140 hectares of green belt land, but gained another 100 elsewhere. In total, then, it lost 40. For those who are keeping score, that's just over 0.1 per cent of all its green belt land.
And this, remember, is not 0.1 per cent of the entire green belt – it’s 0.1 per cent of the portion of the green belt which is contained within the official boundaries of the city. The green belt as a whole is approximately 15 times larger, and that isn’t going anywhere either.
It'd probably be foolish to scrap the green belt altogether, and simply let the construction industry let rip. But it's equally naive to imagine that this land is, and must always remain, inviolable.
London can build the extra homes that its population needs. We've more than enough space.