Projecting Incidence and Costs of Sprawl in the United States

The purpose of this research is to project historical national development patterns (sprawl, or uncontrolled growth) into the future and measure the impacts of this development compared with a more controlled development future. The costs of sprawl are calculated from 25-year growth projections in which resulting impacts are recorded in each of 3,100 counties nationwide. Unique regional definitions of urban, suburban, rural, and undeveloped counties are formulated according to density and prior levels of development. Then sprawl is defined as significant residential and nonresidential development in rural and undeveloped counties. Sprawl is subsequently controlled both within a region and within a county to contain growth in the most developed portions of each, using the equivalent of urban growth boundaries at the regional level and urban service areas at the county level. A future with and without controls generates the differences in development in particular locations. Differences in counties with respect to land conversion rates, road development requirements, housing unit mix and costs, and public-service availability and costs determine growth impacts under the two scenarios. The difference between the two analyses provides empirical evidence of the likely impact of a future with sprawl as opposed to one in which it is reduced.