Climate change is exacerbating forest fires, including—perhaps especially—where the wild meets suburbia.
FOR TERRIFYING SPECTACLE, few events match the full-throated fury of a crowning forest fire. Such a fire moves fast. Sheets of flame flash through the canopy under a seething orange wall as high as a 30-storey skyscraper, with pillars of smoke that can tower 50 times that height.
I live in Greater Victoria’s forested fringe—the “wildland-urban interface” in Fire Boss lingo. Like many, I’m watching trees around me die from climate warming. I confess, there is now seldom a day during the still, tinder-dry afternoons of high summer when the leaves suddenly rustle in an abrupt breeze, that I don’t step outside to nervously sniff the air for that smudgy whiff of woodsmoke.
Forest fires menacing Williams Lake residential district in July 2017 (Photo: courtesy Ministry of Lands, Forest and Natural Resources)
Big fires make their own weather. They suck moisture out of the atmosphere, drying and heating to a flashpoint what’s already dry and hot. They create windstorms to feed their appetite for oxygen. Tornadoes of superheated flame spin away. Trees shriek as they vaporize at 1,200°C—although physics says the noise is sap transforming instantly to steam.
Should this holocaust scenario concern most of us in our comfortable, tree-shaded city homes? Increasingly, warn scientists and emergency measures specialists, the uncomfortable conclusion is “Yes.”
Chris Bone, an expert on the role of climate change and forest policies in driving wildfires and other events, contemplates wildfire from above a native plant garden at the University of Victoria. He thinks that like the great earthquake which may happen tomorrow—or a hundred years from now—the visitation of urban wildfire is not a question of “if,” but “when.”
We generally live as though catastrophe weren’t imminent. In truth, conditions already exist here that make fires like those in California or Alberta possible. “A lot of people think we live in the rainforest and that’s exacerbating the problem,” says Bone, an assistant professor in geography. “We don’t live in the rainforest. We have more of a ‘coastal California’ climate. The south island does not get a lot of rain in the summers.” If climate models are right—so far, they’ve been accurate—climate warming will make this region even more susceptible to wildfire.
He’s careful to point out that while people crave certainty in the face of uncertainty, and simplicity rather than complexity, the impact of our looming climate emergency won’t be linear in progression. There’ll be variability in seasonal weather. Trends are the concern—frequency, length, and intensity of extreme weather episodes, whether wet or dry, cold or hot.
One consistency in those urban wildfires devastating communities in the United States for the past few decades is this: they occur during dry spells after three to four days of very hot temperatures and then, as winds tick up, they overwhelm firefighters. Since 2014, almost 50 firefighters have been killed trying to contain wildfires in the US, 19 of them one entire crew of “hotshot” specialists. They perished together in a conflagration threatening the town of Yarnell, Arizona in 2013.
Crowning fires first flash through the dry canopy and then incinerate what’s beneath, fed by ground cover and debris. The speed with which they can accelerate is mind-boggling.
Artist Frank Ebermann built his house and studio in a pristine, tranquil forest landscape about a 20-minute drive south of Houston on the Yellowhead Highway, midway between Prince George and Prince Rupert. At the end of May, 1983, he heard heavy equipment thundering past his studio. The trucks carried fire suppression specialists. But they weren’t going to a fire; they were running from one. Ebermann scooped up his little daughter Amai, his wife Sophia, and fled, too.
That blaze, dubbed “Swiss Burn,” was a monster, set loose by an angler’s campfire. Eight minutes later the fire covered a square kilometre. Two hours later it was 10 square kilometres. It expanded by one square kilometre per hour. Smoke eclipsed the sun. Flaming embers showered out of the darkness. After seven hours, smouldering ash and charred snags covered an area the size of Victoria, Oak Bay, Esquimalt, View Royal and Colwood combined.
“It was like Dante’s Inferno,” Ebermann told me. “Valleys boiling with flames. The burn made its own firestorm, uprooting the trees as it went.” In minutes, he and seven other families were homeless. The experience had one other big effect. “This fire tore me away from any materialism,” he said. “We want to own the beautiful scenery. But we never really own anything.”
Aerial drop of fire retardant near an Ashcroft home (Photo: courtesy Ministry of Lands, Forest and Natural Resources)
In 2018, similar fires swept through Paradise, California. They burned so hot, car tires melted. So did the sneakers of those trying to flee on foot through the streets. Images from that fire, in which people burned to death in their escape vehicles, haunt Bone—especially when he considers them in the context of new residential developments in Greater Victoria’s wildland-urban interface.
“I think about Paradise and how trapped those people were. Those people had no way to escape. I look at an area like that [wildland-urban interface development in Langford, for example] and I have real concern. How strategic are we being?” Not very, according to a 2018 study for the B.C. government. Addressing the New Normal: 21st Century Disaster Management in British Columbia by George Abbott and Chief Maureen Chapman is a disturbing restatement of warnings provided by successive provincial auditors-general over almost 20 years. “Despite earnest efforts,” it said, “BC has made disappointingly little progress on the goal of enhanced community safety since 2003.” It said at least 80 communities have completed wildfire protection plans but half of them still haven’t done anything to actually mitigate risk by reducing on-the-ground-fuel, clearing underbrush, or thinning forest stands adjacent to residential districts.
A 2015 study by the Institute for Catastrophic Loss Reduction, a think tank for Canada’s insurance industry, concluded that in Kelowna, where 239 homes were burned during a wildland-urban interface fire in 2003, present conditions could result in a repeat disaster. Reasons for inaction given by municipal politicians, the BC government report said, are that tax dollars are committed to building and maintaining water, sewer, roads, street lights, parks, recreation, and solid waste disposal. The infrastructure supports residential growth and thus an expanded tax base. Forests adjacent to residential development are deemed somebody else’s problem and responsibility. But whose problem does it become if a crowning wildfire rips through a city’s residential fringe?
THAT'S A QUESTION WE SHOULD ALL ASK our municipal governments. In Slave Lake, Alberta in 2011, planners said that the city’s evacuation seemed unthinkable. The next day thousands bolted through flames and smoke so thick they couldn’t see where they were driving. In Fort McMurray, in 2016, thousands were again forced to run a gauntlet of fire, escaping while fire destroyed 2,400 buildings and insured losses approached $4 billion. In Portugal, in 2017, 30 people burned in their vehicles while trying to escape a blaze; 17 more died trying to flee abandoned vehicles on foot. Scores of tourists in Greece died when they were trapped by wildfire.
And the risk here grows, it does not diminish. Research published last year in the International Journal of Wildland Fire estimates more than 55,000 square kilometres in B.C. now lie in the wildfire-urban interface. The authors of Mapping Canadian Wildland Fire Interface Areas, Lynn Johnston of Natural Resources Canada and Mike Flannigan of the University of Alberta, conclude that this danger zone both expands and becomes more hazardous with climate warming.
In Greater Victoria, for example, expect the frequency of very hot days to reach an average of 36 per summer. Hottest day temperatures are projected to rise to 36°C. And while we’ll get more precipitation overall, summer rainfall will dwindle by at least 20 percent while days of drought will lengthen by 20 percent.
Vancouver Island was already rated at a Level Three drought—one notch below the driest tier—before the end of May this year. In the Comox Valley, only 34 per cent of normal rainfall arrived. In Kelowna, the rainfall was 50 percent less. And it’s been hot. More than 30 daytime high temperature records were broken across the province on a single day in March.
Furthermore, as it gets hotter and dryer, lightning storms will become more frequent. Right now, Canada gets about 2.25 million lightning strikes per year. They are responsible for almost half our wildfires—humans start slightly more than 50 percent. There will be 12 percent more strikes for every degree of global temperature rise. For every two lightning strikes today, there will soon be three.
In BC, Addressing the New Normal found that more than 16,000 square kilometres of forest pose high to moderate risk of wildfires expanding rapidly into major residential areas. Worse, it warns that such wildfires—which are now bigger, burn hotter and move faster because of global warming—are becoming the norm.
“The wildfire zone is not only getting closer to people, but people are getting closer to the wildfire zone,” the study points out, citing BC Auditor General Wayne Strelioff’s 2001 report Managing Interface Fire Risks; former Manitoba Premier Gary Filmon’s report Firestorm, triggered by events in 2003; and present Auditor General Carol Bellringer’s 2018 assessment of subsequent foot-dragging and inaction. This too is a concern, considering that people caused more than half the wildfires that cost BC taxpayers $3 billion between 2003 and 2017.
“British Columbia has the highest risk of interface fires in Canada because of its climate and topography,” the report by Abbott and Chapman reiterates. The risks are increasing as a result of two key factors—the continuing growth in the number of people choosing to live in or near the forests and grassland areas and the significant buildup of forest fuels resulting from years of successful fire suppression activities. “Fire experts fear that, if actions are not taken soon to reduce the risks associated with interface fires, it is only a matter of time before these fires will exceed firefighters’ ability to contain them and that this might lead to significant loss of life and property,” the report warns.
Clearly, it’s time we had a vigorous, engaged, adult conversation at the community level about the danger zone at the fringes of Greater Victoria, where residential districts bleed into forest land and forest intrudes into the built landscape. Often, these fringes are among the most desirable neighbourhoods. They offer shady, countrified respite from the noise, heat, traffic and pavement of downtown. Developers like them because they sell quickly. And, in the short term, revenue-hungry municipal politicians appear to discount long-term hazards against short-term revenue gains.
The wildland-urban interface on the Saanich Peninsula north of Victoria, as seen from the top of PKOLS/Mount Douglas (Photo: Stephen Hume)
Wildfire science calls it “the expanding bull’s-eye effect.” As a city expands from its centre, the fire-exposed perimeter lengthens, placing larger areas within the danger zone. Visit Greater Victoria’s tony, up-market neighbourhoods at Broadmead, Dean Park or some of the newer subdivisions in Langford, for example, and houses and gardens are deeply integrated into heavily forested slopes. Yet housing developments zoned on forested hillsides are also at highest risk. Fire moves fastest (in California they moved with explosive speed) while burning up-slope, where canopy and underbrush are close to structures.
This forest-city interface is where risk is greatest for conflagrations like those which forced evacuations of 200,000 people in BC and Alberta alone over the last 15 years. More than 36,000 wild-land-urban interface homes and businesses have now been razed across California, BC and Alberta.
As environmental writer Glen Martin recently observed in California Magazine: “From a firefighter’s perspective, wildland-urban interface combines the worst of both realms (suburb and forest): interface areas are not only cheek-to-jowl with fuel-rich forests, they’re also often characterized by dense housing tracts landscaped with lush, highly flammable vegetation. Today’s wildfires, in short, are not your grandpa’s wildfires; they’re usually hybrid-human started fires, involving both structures and forests, which greatly complicates the task for wildfire fighters and escalates the cost in life and property.”
GREATER VICTORIA might serve as a textbook model of wildland-urban interface fire hazard. The city expanded from a 75-kilometre bull’s eye to one with a 1,650-kilometre circumference of wildland-urban interface. In addition, an urban forest covers much of its footprint. A Habitat Acquisition Trust study published in 2008 calculated that about 40 percent of Greater Victoria’s 696.2 square kilometre land area was then under tree canopy. Considering that the urban core of Victoria has 150,000 trees in a scant 19.5 square kilometres, similar density would mean perhaps five million trees over the rest of the capital region, even with declines in forested area.
This forest is highly valued by residents—for good reason. It’s a central element in regional identity. It provides shade and greenery to offset pavement. It lessens runoff. It adds to biodiversity by offering habitat to urban wildlife. It produces oxygen, stores carbon and absorbs both air and water pollutants. Yet there’s a tradeoff. Many trees are non-native and drought-intolerant. They contribute to the deepening fire hazard. This alone warrants frank public discussion about what faces the City as summer rains diminish, temperatures rise, and very hot days and very dry spells become more frequent and last much longer.
“We need to rethink our approach to urban landscape and start planning it in a much more holistic way,” says Johan Feddema, who studies the consequences of human actions on the environment and the effects of climate change upon society. The UVic scientist has examined the impacts of climate conditions upon severe crown fires.
Everybody loves the urban forest, he notes, but it has a downside. During transpiration, trees extract water from the ground and transfer it to dry air. US Geological Survey scientists calculate that one large deciduous tree can extract 150,000 litres a year from surface soil—most during summer months when foliage is heaviest. And the hotter it gets, the greater the rate. Our beloved shade trees may actually be helping to dry out their surroundings faster during extended droughts.
Does that mean we should mow down the urban forest? Of course not. Trees are important for sequestering carbon, and deciduous hardwoods like native oak and maple are among the top carbon-storers.
Feddema says we should be aware of these natural processes and think about different kinds and mixes of vegetation—drought and fire-resistant native plants—and how to design urban infrastructure for cooling rather than for convenience or architectural aesthetic. Plan for more open green space, but with warming-appropriate vegetation. Even the shape and placement of green space and tall buildings in the urban core can enhance or inhibit circulation patterns that might be cooling other parts of the city.
“Yes,” muses Feddema, “we need to think creatively about advocating for a holistic way of planning, designing and building our city.” Bone echoes that idea. If municipalities continue with zoning that permits residential dwellings in the wildland-urban interface hazard zone, he says, they have an obligation to engage in vigorous proactive education of residents about the dangers.
An example of the education needed is warning people that one of the biggest risks that their house will burn down during a wildfire is as simple as needles collecting in rain gutters. And how many of us actually know our urban evacuation routes, have mapped alternative routes, or have even thought about what we will do if those carefully planned evacuation routes are blocked?
The Capital Regional District voted unanimously last February to declare a climate emergency. It’s a worthy initiative. But, like many such programs, it seems heavy on mission statements and global plans for reducing greenhouse gas emissions, and less emphatic about practical but painful local decisions like reforming building codes or enacting stringent zoning bylaws which address the threat of urban wildfire.
Emergency measures planners provide clear directions about what needs to be done: reduce ground fuel; increase the allowable margin between houses and forest cover; mandate flame-resistant building materials; regulate garden shrubbery and landscaping.
One 2010 study found that by treating 10 percent of the adjacent forest landscape as a buffer zone in which ground fuel is removed, trees thinned and limbed, and underbrush cleared, risk of wildfire loss is reduced 70 percent. Considering that between 2014 and 2017, wildfires in western Canada and the US cost insurers almost $60 billion (CAD) in structural losses, this is something to think seriously about.
IN CANADA AND BC, the danger trend is relentlessly upward. Wildfire scientists don’t doubt this is a direct consequence of our developing climate emergency. Right now, on average, 70,000 people and 20 communities a year in Canada are directly affected by wildfire events. That’s a 40 percent increase since 1980. BC tops the national list. And the trend will accelerate, not slow, as climate warms and summers get hotter and dryer. Ottawa expects the annual cost of fire protection to double by 2040.
Some experts now argue that the former worst-case looks more like a future best-case as human beings pour planet-warming carbon dioxide into the atmosphere faster than at any time in human history. Fires of once-unimaginable intensity that happened every 20 years now occur every year. And the risks today are greater because wildfire-urban interface areas are vastly larger.
By mid-May, half a month early, the 2019 fire season was already in full swing. Almost 14,000 fire refugees had already been evacuated from a vast arc through northern BC and Alberta and culminating in northern Ontario.
Last year, 2018, was the worst on record for wildfires, dislocated populations, secondary health effects—emergency admissions for respiratory ailments doubled in BC as smoke became pervasive—and soaring fire suppression costs. In California, 81 people were dead, 870 were missing and almost 19,000 buildings had been destroyed in four hours. The year before that, 2017, had been the worst until 2018. In 2016, more than 88,000 people were evacuated as wildfire ripped through Fort McMurray in Alberta and destroyed 2,400 buildings. The year before that, 2015, was the worst-ever fire season for the US, representing a 133 percent increase over the long-term 50-year average in wildfire burn.
No one welcomes a bearer of bad news, but it’s obvious that some version of the fire demon is waiting to visit itself upon Greater Victoria. We can’t prevent wildfire, it’s part of our environment, but we can adapt intelligently. Time to start thinking and talking seriously about that.
Stephen Hume has spent half a century as a journalist writing about Western Canada, the North, BC and the Island. His byline has appeared in most major Canadian newspapers.
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