Does a growing population contribute to urban sprawl? The relationship between population growth and sprawl appears obvious to some but is denied or minimized by just as many. What has been lacking is a systematic, comprehensive, consistent means of quantifying the role of population growth in sprawl in recent decades. A national study by NumbersUSA, “Weighing Sprawl Factors in Large U.S. Cities” does just that. The Chesapeake Bay Watershed is home to more than 3,000 species of plants and animals, and nearly 15 million people today. The restoration and long-term protection of the Bay depends on halting the urban sprawl that is threatening the biodiversity and water quality of the area.