Wildfires that destroy communities as well as wilderness are becoming increasingly common across North America.
While the forest fire season in Canada and the U.S. traditionally peaks in late summer and early fall, climate change is thought to be creating a longer fire season in many parts of the continent. In May 2011, for example, there were more than 100 forest fires across Alberta, and a large portion of the town of Slave Lake was destroyed by flames. The previous month, wildfires burned more than 150 buildings in towns near Fort Worth, Texas. A wildfire in Halifax in May 2009 forced 1,200 from their homes.
Adding to the problem is the fact that more communities and industrial operations are expanding into what were once remote, sparsely populated regions. The trend of building deeper and deeper into the woodland is increasing the risk of fire damage, said Michael Feller, associate professor at the University of British Columbia's forest sciences department.
"No matter what province you're in, more and more people are building more and more houses stretching out into the adjacent forests, in smaller communities and even in the larger communities," he said.
"Like Vancouver for example, houses are spreading out up onto the forested areas of the edge of the current settlement. Even in big cities, it's an issue.... it's only a matter of time before more houses go up."
The science of wildfires
A wildfire is one of the most powerful forces in nature, as anyone who has watched its frightening fury up close can attest. When experts explain fire, they often talk about something called the "fire triangle" and its three equal sides, representing heat, fuel and oxygen. All three must interact for a fire to get started and to keep going. Take away any one of these ingredients and the fire is suppressed.
Canada has already seen what can happen when they do.
In the summer of 2003, people in Kelowna and the Okanagan Valley in southeastern B.C. watched helplessly from the sidelines as their houses went up in smoke. About 50,000 people were evacuated from their homes. The firefighting costs alone reached upwards of $400 million, and insurance payouts reached $200 million.
It didn't have to be this bad.
Reducing the risk
A provincial inquiry into the Kelowna fires later ruled that one of the reasons they were so severe was because very little was done to reduce the amount of dead wood and brush on the forest floor.
As well, many of the homes were made of flammable materials. Some roofs were covered in untreated cedar wood shakes — ideal fuel for a roaring fire. Had they been made of more fire-repellent materials such as metal, clay tile or asphalt, several of the homes might have been saved, Feller said.
"I'm sure there would have been a lot less property damage," he said.
These common-sense tips are the principles behind the FireSmart Manual, a guide to help homeowners reduce the risk of losing their houses to forest fires. It was produced by the Partners in Protection organization based in Edmonton.
Its recommendations include ensuring that the immediate vicinity around the house is free of items that would fuel a fire, such as dry shrubs or a woodpile. Trees that are more combustible, such as pine and spruce, should be removed, or spaced at least 3 to 6 metres apart so flames can't spread as easily.
These adjustments can't fire-proof a home, but can cut the risk of damage significantly, said Kelly O'Shea of Partners in Protection.
Some communities, such as Langford, B.C., have factored these principles into their municipal bylaws. Rob Buchan, Langford's clerk-administrator, said that after 2002, each new home had to meet FireSmart guidelines.
In the aftermath of the Kelowna and Okanagan Valley blazes, more communities adopted the fire-prevention strategies. But they are the minority in Canada, said Feller.
Because the responsibility lies at the municipal government level, there isn't consistent forest-fire risk management legislation in place, he said.
"Some jurisdictions have good regulations and others have none... So people build wooden houses in fire-prone areas. And obviously, they are very threatened. It's highly variable," Feller said.
Awareness is key
Although the FireSmart guidelines have been promoted countrywide, people need to be more aware of them, he said.
"I was visiting some of the 2003 fire areas in B.C. within a few months of the houses being burned," he said. "And they had rebuilt using flammable materials and it was as though the fires had never occurred."
'I was visiting some of the 2003 fire areas in B.C. within a few months of the houses being burned. And they had rebuilt using flammable materials and it was as though the fires had never occurred.' —Michael Feller, associate professor at the University of British Columbia
The forest fire risk to homes in Canada is being compounded by two factors: global warming and the pine beetle, said Feller, who specializes in forest fire ecology.
He said studies have shown that the likelihood of a severe fire season has increased due to warmer, drier and windier summers.
"Heat dries out fuels [twigs and branches] on the ground, which makes them more susceptible to being burnt in the first place. And once they do catch fire, they spread more quickly. And if you have strong winds, that fans the flames and increases fire activities," he said.
And the voracious pine beetle is eating its way through Canada's forests, leaving behind brittle trees that could serve as kindling to any potential fire.
"Climate change is allowing certain insects, such as the mountain pine beetle in B.C. and Alberta in particular, to destroy or kill millions of hectares of trees …" Feller said. "And as long as the foliage remains on them, they're going to be much more prone to fires."
Feller said homeowners should remove potential sources of fires from around their properties and also encourage local government and forestry officials to reduce dry forest brush in the area.