Chris Leinberger’s new Footloose and Fancy Free “Field Survey of Walkable Urban Places” study isn’t exactly of the highest scientific caliber: I won’t begin listing his omissions, since that’d be tiring; and I personally prize a “streetcar urbanism” of continuously enjoyable expanses of urban fabric rather than periodic episodes of frenzied activity focused around rapid-transit nodes. However, it does try to put some background behind one curious observation about LA: “there are 10 million people who have, between them, maybe five places to go for a Sunday walk.” Therefore, those five places (now up to 15, by Leinberger’s rather more lenient definition) are absolutely thronged with crowds (1.13 million Southern Californians apiece, by his calculation).

His most interesting conclusion:

If the bottom 10 metropolitan areas developed as many walkable urban places on a per capita basis as the top 10 have done to date, there would be approximately 40 additional walkable urban places developed in these metro areas, probably representing tens of billions of dollars of real estate development.

Some worry that such developments appeal only to a small slice of the population — and that the market for retail of this variety is especially thin — and therefore that cannibalization will inevitably occur when new developments attempt to create walkable places. However, the demand is apparently quite a bit deeper than skeptics suspect; if demand warrants at least one walkable place per 500,000 residents (and the D.C. area apparently supports twice that level), then, say, the Twin Cities could support six or seven such places — far above the three in existence today.