For all the popular invective and academic arguments about "sprawl," it's almost impossible to get a clear measurement of how much sprawl there actually is. That's largely because it's hard to pin a precise definition onto the word. In Don't Call It Sprawl: Metropolitan Structure in the Twenty-First Century (Cambridge University Press), the economist William T. Bogart offers "a simple test to apply to any purported definition of sprawl. Apply it to Central Park in Manhattan. In most cases, you will find that it implies that Central Park should be developed. For fun, you can point this out to the definer, who will quickly assure you that he or she didn't mean it that way."
As its title suggests, Bogart's book suggests throwing out the pejorative term "sprawl" altogether and approaching our cities and suburbs with a different lens. Borrowing models from the study of international trade, Bogart views metropolitan regions as dynamic systems; he rejects any approach that confuses a static snapshot of a region with the region itself. By no means a libertarian purist -- he is willing, for example, to consider certain subsidies to urban downtowns -- he is nonetheless skeptical of centralized planning and of reformers who would rather impose their will on the landscape than "use the existing momentum but...deflect it in a better direction." He is also a clever writer, always willing to leaven a dry economic passage with a joke or an allusion to speculative fiction.
Bogart is dean of academic affairs at York College in Pennsylvania. I spoke to him by phone on December 11.
reason: If we shouldn't call it sprawl, what should we call it?
Bogart: "Trading places." It's a more accurate description of how metropolitan areas are structured today: Parts interact with each other by trading goods and services, which includes people moving from place to place and consuming and producing goods and services.
It's also an explicitly dynamic term. Over the course of a day the populations of different parts of metropolitan areas change, and over the course of time the populations of metropolitan areas change. Too much of the discussion about metropolitan structure has been too narrowly focused, in both space and time -- it looks at a very small part of a metropolitan area at only one point in time.
There's also a wonderful movie called Trading Places, and one of the themes of that movie is that two people whose lives didn't seem to be connected -- who seemed to be in competition -- in fact had a common interest. That's an excellent metaphor for the position many local governments find themselves in. It seems that they are competing with each other for business, housing, and other resources, but fundamentally they have a shared interest in the metropolitan area succeeding.
reason: How does trade among suburbs and neighborhoods resemble trade among nations?
Bogart: Importing is consuming more than you produce. Exporting is producing more than you consume. So really the difference is over what geographical region are we considering the production and consumption that's going on. We're very familiar with it with countries, because -- (chuckles) this is the sort of thing that reason readers will be familiar with -- there are lots of government regulations and often taxes involved when good and services cross national boundaries. There typically are not those kinds of regulatory or tax barriers when goods and services cross local boundaries. In that sense it's much less visible, because there isn't a government agency collecting information on it. But it is very large and very pervasive.
Zoning is a trade regulation. If you do not allow a certain type of activity to occur within your municipality, you have automatically determined that you will not be exporting it. It can also affect trade indirectly, in that if you allow a particular type of land use but either restrict the way it is engaged in or restrict the total amount of it, you can change the pattern of imports and exports relative to what it otherwise would have been. If a Wal-Mart or some kind of a superstore wants to locate in your town, and you don't allow retail with a large enough footprint or with the type of traffic that a superstore needs, you haven't gotten rid of Wal-Mart. You have made sure that the residents of your town will be importing the services of Wal-Mart from someplace else.
reason: If zoning is a trade regulation, then what's the metropolitan equivalent of a free trade policy?
Bogart: One of the justifications for these sorts of policies is the control of externalities. To economists, the right approach is: If there are spillovers, address them directly. Don't constrain developers from coming up with clever solutions to those problems. So if you're concerned about traffic congestion, don't ban a land use. Require a certain level of traffic flow and let the developers figure out how they can organize themselves, including perhaps contributing the infrastructure, to maintain that type of traffic flow.
For example, Houston is not zoned. It is not true, though, that Houston does not engage in land use control. The municipal government does directly prohibit or restrict certain types of negative externalities. And the municipal government participates in enforcing contractual arrangements. If someone is doing something that is not in conformance with the local covenant, the municipal government will take the lead, legally, in enforcing that covenant. In a sense they've privatized and contracted the services of what in most towns is the job of a planning department.
reason: Why don't you think the Houston model has been imitated?
Bogart: I have two answers for that. One is: I'm completely baffled. (laughs) The other has to do with the political economy of the planning profession and the incentives in governments. The planning profession is not held accountable for bad advice.