After Fort McMurray: Where are the World's Most Fire-Prone Cities?

May 16, 2016
Images of the devastated Canadian city show just how destructive fire can be to urban populations. But the risk is greatest in informal settlements, where high population density and low-grade construction can be a deadly combination

With patches of lawn on fire in the front yards of his neighbourhood’s suburban homes and flames rising up the trees at the back, Jared Sabovitch frantically got into his car and began driving away from his home in Fort McMurray, Alberta, the Canadian city recently overtaken by wildfires.

“Hasty exit,” he said as he drove, the phone in his hand recording a video he would later post to Instagram. “That might have been the last time I ever saw my house, right there.”

Sabovitch fled along with roughly 90,000 other residents, making this the largest evacuation on record in Canada. Red smoke and flames filled the sky behind him as he drove away.

The wildfire has now burned more than half a million acres, and continues to spread. Most of Fort McMurray was spared destruction, but 2,400 homes fell to the fire, Sabovitch’s included.

That a wildfire would roll through this northern, boreal forest-shrouded oil boomtown was not inevitable, but it was not surprising either. “When you look at satellite images of Fort McMurray from before and after the fire, you can see that because of the urbanisation that went on there, the city has encroached into the surrounding forestland,” says Heiko Balzter, director of the Centre for Landscape and Climate Research at the University of Leicester.

Where there are forests, there are fires. In 1950, this same part of Canada was engulfed in a wildfire that burned for five months straight, putting nearly 4 million acres of forest up in smoke. “So this fire is not even huge by historic standards,” says Stephen J Pyne, a fire expert and professor at Arizona State University. “The reason it’s significant is that, unlike 1950, there’s a relatively modern community right in the middle of it.”

There’s no definitive list of the world’s most fire-prone cities, mostly because of the many and often compounding factors that can increase the likelihood of fires. As well as the growing vulnerability caused by climate change and poor urban management, other factors range from the prevalence of dry vegetation and use of flammable building materials to widespread open-flame cooking and, all too frequently, arson.

But there is one relatively straightforward indicator of fire risk that can be tracked and mapped. It’s what researchers and foresters call the wildland-urban interface: areas where naturally fire-prone wilderness areas such as forests and shrublands are close to, or even intermingled with, housing developments, neighbourhoods or even – as in the case of Fort McMurray – entire cities. ...