Urban planners and other academic researchers have attempted to define urban sprawl, but few of the definitions have gained general acceptance.
Florida planner Reid Ewing, one of the architects of Florida’s statewide growth management plan, believes that sprawl can be characterized by four factors:
Low-density development, usually consisting of single-family homes on large lots;
Strip commercial development;
Scattered development, where commercial, residential, and retail developments are not integrated or close together;
Leapfrog development where drivers view long stretches of vacant land between developments.
Yet, even this is an incomplete list and an unsatisfactory characterization of the development process. For example, objections to scattered or leapfrog development are often rooted in static concepts of urban development. Scattered sites are eventually connected through the "in-fill" process — usually commercial and higher density residential development. The pattern of development in and of itself is not a primary concern of planners.
Concerns over sprawl, writes Ewing, center on the effects of land uses, not the specific characteristics of urban development. "It is the impacts of development that render development patterns undesirable," he says, "not the patterns themselves." So the problem with suburbanization is not the mere existence of single family houses on large lots. Rather, the effects on infrastructure, congestion, "balanced" economic development, and the environment motivate concerns about continuous low-density development. However, these effects are difficult to quantify and provide little justification for public policy.
Definitions of sprawl in the popular press and public debates have tended to take on more general meanings than the specific ones found in academic journals and research monographs. Urban economist John F. McDonald probably captures the spirit of most definitions of urban sprawl when he characterizes it as
Low-density development that is dispersed and uses a lot of land;
Geographic separation of essential places such as work, homes, schools, and shopping areas; and
An almost complete dependence on automobiles for travel.
The first two elements of this definition are probably closer to how policy analysts characterize the problem of urban sprawl in Michigan. Automobile dependence does not appear to be as important a concern as in other states such as Oregon, Florida, California, Colorado, or Arizona except to the extent it affects traffic congestion.
Even this definition is more technical than most media accounts use. Many, including some urban planners, tend to define urban sprawl as simply the process of moving out of congested central cities. In most cases, popular criticism of sprawl is a reaction to the recent suburbanization and decentralization of people. People are leaving congested, dense cities for less dense suburban locations, making suburban locations more crowded and congested.