Many environmentalists believe that denser cities are better for the environment, as they use up less land and also require less energy for activities such as commuting. There’s also a perception that sprawl results from a lack of “planning”. But is this necessarily the case?

Wendell Cox has some surprising data on this topic:

The smallest lot sizes are one-half smaller than the national median of 0.26 acres. The major California metropolitan areas have among the smallest median lot sizes for existing 1-unit houses. This is not surprising, since California has the densest urbanization in the nation, as well as the first, second and third most densely populated major urban areas (Los Angeles, San Francisco and San Jose, in that order and ahead of fourth place New York). . . .

Houston’s small lot size (0.18 acres) is particularly surprising, given the general contempt of many planners who characterize it as excessively sprawling (Figure 2). In fact, Houston has smaller lot sizes than urban planning favorite Portland and has an urban density only a little less dense (Note 2). . . .

In fact, the four largest Texas metropolitan areas, Dallas-Fort Worth, Houston, San Antonio, and Austin each have median lot sizes of from 0.18 acres to 0.25 acres, small or smaller than Philadelphia, Boston or Washington. The market orientation of Texas land and residential development have not resulted in less efficient use of land.

All of this is a yet another reminder that the data does not always support pre-conceived perceptions.

This is not to say there aren’t cases where cities are both denser than Houston and more highly regulated.  But keep in mind that the density you see in places like Manhattan was created during a period where land use was much less strictly regulated than today.  If San Francisco were to make its land use rules more laissez-faire, it would probably be a net plus for the environment.

There is an ongoing battle between what might be called “scientific environmentalism” and “romantic environmentalism”.  The latter favors closing down nuclear power plants, restricting construction in attractive San Francisco and West LA neighborhoods, and banning GMO foods that require less land, pesticides and herbicides.  Can you guess which side I favor?

PS.  Even Houston is not entirely laissez faire, but it does allow a lot of infill townhouses in the closer in neighborhoods: