U.S. Sprawl Peaked in 1994 and Has Been Declining Ever Since

We tend to think of urban sprawl in America as a product of the Interstate Highway System built in the 1950s and 1960s. Metro area residents who might have been inclined to live near work in the city took the chance to head up the road, find a parcel of land for a single-family home, and commute into work by car. Others followed and pushed development farther out until we got the sprawled out metros we know today.

Some new work published today in the journal PNAS challenges this timeline—showing evidence of sprawl dating back to the 1920s. Using precise, street-level data at the county level, Christopher Barrington-Leigh of McGill University and Adam Millard-Ball of UC-Santa Cruz report that sprawl was rising well before 1950, then grew steadily through the 1990s. The researchers also conclude that U.S. sprawl peaked around 1994 and has been falling ever since.