Sprawl is primarily caused by natural population growth and immigration, said Anthony Downs, a senior fellow at the Washington DC-based Brookings Institute, and there isn't a whole lot that local governments can do to prevent those actions. Growing populations in areas have caused the building of low-density housing on large plots of land, the loss of farmland and major traffic congestion.

So far, most metropolitan areas, with the exception of Portland, OR, have been successful in combating sprawl, Downs said, and there may be little they can do. "Unfortunately I don't think there's any cure for traffic congestion," he said. "It's getting worse everywhere, and there's nothing we can do to stop it."

But a few projects with large retail components have worked, pointed out Rick Peiser, a professor of real estate development at Harvard University. He mentioned the downtowns of Pasadena, CA; and Waltham, MA; as good examples of mixed-use retail working with high density housing, as well as the Mockingbird Station development in Dallas, just north of downtown.