On June 26, 2012, a fire in the Waldo Canyon region of El Paso County, Colo., jumped its containment line and burst into the western edge of Colorado Springs. By the time firefighters had controlled its spread, 346 homes had burned to the ground. Having forced the evacuation of 32,000 residents and resulted in more than $350 million in insurance claims, the Waldo Canyon Fire was labeled the most destructive in Colorado's history.
It proved to be a fragile record. Less than a year later, it was broken less than 30 miles to the northeast. The Black Forest Fire, which broke out a week ago under record heat, dryness and strong winds, had already claimed more than 360 structures as of yesterday and two deaths. Firefighters had the blaze largely contained yesterday evening, but residents were encouraged to remain out of the area.
The destructive power of these fires stems not so much from their size or intensity as from their proximity to people and the structures and infrastructure they build. Contrary to its name, Black Forest, Colo., is not a true forest at all but a thickly wooded neighborhood on the northeastern edge of Colorado Springs. It is part of what forest managers describe as the "wildland-urban interface" (WUI), a buffer zone between the wilderness and human development containing elements of both.
When wildfire moves out of pure wilderness and into the WUI, it changes the choices facing firefighters, in a big way, said Steve Gage, assistant director of operations and longtime firefighter with the Forest Service.
"Without the WUI, we have more options, more decision space," he said. "We don't need to worry about private property being a value at risk. In many cases, we can take the fire on our own ground, in our own way."
He added, "If you're dealing with a fire in the WUI, your decision space gets a lot smaller."
In the priorities facing firefighters, protection of private property ranks right at the top, second only to the defense and protection of human life, he said. Protection of infrastructure, watersheds and cultural sites must take third place.
An expensive proposition
Development in the WUI doesn't just pose a challenge after a fire has started. It can also increase the likelihood of an ignition event, Gage said.
"It can be power lines, vehicle fires or children with matches," he said. "In pure nature, there are very few causal agents aside from lightning" capable of starting a fire.
The presence of humans also limits forest managers' options in treating areas against future burns. Proximity to houses and people means the Forest Service can't conduct controlled burns, or allow small fires to burn themselves out. Over time, brush accumulates in forests and can result in hotter, more widespread fires if not manually thinned.
More importantly, perhaps, it forces firefighters into a defensive position. Rather than letting a fire burn available fuels and exhaust itself, they must hold lines fast wherever private property is present. This can draw resources and personnel away from other areas and can ultimately add significantly to the cost of fighting the fire.
According to research from the Montana-based nonprofit research group Headwaters Economics, in some areas of the rugged Sierra Nevadas in California, the cost of defending a single home can rise to more than $500,000.
"We're talking about situations where it'd be less expensive to let the home burn down and rebuild it from scratch," said Ray Rasker, executive director of Headwaters Economics.
Those costs rise with temperature, as is expected in coming decades due to climate change. Three studies carried out by Headwaters Economics found that the cost of defending homes from wildfire doubles with a summer temperature increase of 1 degree Fahrenheit.
More people move to the WUI. Who pays?
The problem is compounded by another trend -- despite fire risks, Americans appear to be migrating steadily from developed areas into the WUI. Of all the states, Washington has the largest concentration of heavily developed WUI, and according to Forest Service researchers, the trend is toward still more dispersed rural communities like Black Forest.
Why, at a historical moment when most of the world is moving toward rapid urbanization, would people look to the woods as a place to build a home? Part of the reason seems to be that, even as the population of the United States increases, many cities and towns are trying to limit growth, said Andy Gray, a research ecologist at the Forest Service's Pacific Northwest Research Station.
"Both Washington and Oregon have put in place land-use development operations to limit urban sprawl, to limit the spread of towns," he said. "At the same time, the number of dispersed houses continues along its same trajectory" of expansion.
In some cases, dispersed houses are second homes for urban dwellers looking to get away from the bustle and hum of the city.
"It's largely people moving out for the amenities," Gray said. "In some cases, people want to be closer to a national park or a geographic feature like a lake. There's a desire among folks to move into these more rural settings, if they can afford it."
There is a fundamental disconnect between people's desire to move into the WUI and the increasing cost of protecting those properties, said Headwaters Economics' Rasker.
"The fundamental problem is, who pays?" he said. The answer, he said, is the Forest Service, Interior Department, Bureau of Land Management and Federal Emergency Management Agency.
"State firefighting agencies pay for it also, but they can seek reimbursement" from their federal partners, he said. "At the end of the line, it's really the federal taxpayer who's footing this bill."
Tomorrow: How insurance, state policy and education can reshape our approach to living in the wildland-urban interface.
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