How low density metros become vulnerable to collapse

There’s a fascinating article in Atlantic Cities about the theory of “low density metropolitan collapse,” using the decline of once-powerful Angkor Wat, Cambodia in the 17th century as a main example. After centuries of prosperity, that city expanded quickly in a sprawling way in a spell of mild weather but crumbled when weather grew more extreme.

One doesn’t have to look too far to find a correlation in Atlanta, with both weather and other stressors showing our vulnerability. Atlanta’s suburban sprawl boomed when rainfall was plentiful and our water supply seemed certain, land was plentiful and cheap, and surging economic growth — the kind that paid for new infrastructure easily — seemed unstoppable.

The fix for this kind of vulnerability, obviously, is to undo sprawl damage. A quote from the article:

The lesson for American and similar land use pattern nations like Canada and Australia is to build compact, flexible settlements. One direction already underway is urban consolidation, in cities such as Miami, Indianapolis, and Louisville. Another is containment of sprawl, similar to Portland and Seattle and now Los Angeles. Finally, Denver, Phoenix, and Dallas are trying to re-knit the suburbs with the cities using light rail to generate development along corridors rather than continuous outward development.

Image of Atlanta sprawl from Discovering Urbanism