Atlanta, Ga., has the worst sprawl in the nation, according to a preliminary study by the Fannie Mae Foundation. Miami, Detroit, Denver, and Dallas round out the top five cities with the most serious sprawl problems. Although Southern and Western metropolitan areas absorbed roughly equal numbers of new residents between 1982 and 1997, the South sprawled out over more than three times as much land as the West, 15.1 million acres versus 4.8 million, said Cornell University professor Rolf Pendall. In Colorado, anti-sprawl activists used Denver’s No. 4 ranking to argue that the state’s voters should approve Amendment 24, a ballot measure that aims to curb sprawl by allowing residents to vote on development proposed for their communities.