Acquitting Sprawl.

Suburban sprawl has been blamed for almost every social ill, with the most common accusations damning it for traffic congestion and the decline of the inner city. But according to a recent study, it's getting a bum rap.

In "Some Realities about Sprawl and Urban Decline"--published in the most recent issue of Housing Policy Debate, a journal of the Fannie Mae Foundation, a private (though tax funded) community development group--Anthony Downs of the Brookings Institution distinguishes sprawl from general suburban development by listing 10 characteristics specific to the former, such as low-density "leapfrog" development, reliance on the private automobile, and a political order in which planning power is fragmented across several municipal authorities. According to Downs, most analysts oversimplify the problem--and possible solutions--by focusing on only a few of sprawl's defining traits.

Downs analyzed data from 1980 and 1990 in 162 urbanized areas to measure both sprawl and urban decline, using nine variables for each. Low or diminishing population density, for example, was a marker for sprawl; so was the ratio of central city density to densities on the outlying fringe. Measures of urban decline included increasing crime rates, decreasing come, and decreasing population.

Downs' conclusion, which he found "very surprising": "There is no meaningful and significant statistical relationship between any of the specific traits of sprawl, or a sprawl index, and either measure of urban decline." The "basic traits of the general growth process"--the relatively high standards required of new housing, the concentration of public housing in urban cores, the exclusionary zoning laws adopted by suburban governments, the tax systems that encourage such laws, and racial discrimination in housing markets--"would produce concentrated minority-group poverty in large cities even if sprawl did not exist."