Halifax Tree Project

Wildfires and Risk to Infrastructure 

Shauna Doll, Raincoast Conservation Foundation

2021-07-27

Links between wildfire and climate change

As I write this, a fire the size of Los Angeles is raging in Oregon; smoke from the Quebec fires that have collectively burned over 60,000 hectares of forest is blanketing Nova Scotia; and a state of emergency has been declared in British Columbia due to a fire season triggered a month early by the now infamous heat-dome that trapped western Canada in an inescapable hot cooker of 45+ degree temperatures in late June. As a result, towns across the country are under evacuation orders or alerts, with 4,300 properties evacuated, and an additional 18,000 on alert in BC alone as of July 22 (CBC News, 2021). Tune into the CBC, CTV, or Global News and coverage is never far away from the unseasonable droughts and hundreds of fires burning across the country—and running through all these news stories is an unsettling theme: this is the “new normal”.

Across the planet, these sorts of natural disasters are occurring at a frequency and severity most people have never seen before. While Canada battles one of its worst wildfire seasons in history, a week of torrential rain in China’s Henan province, described by Chinese State Media as a “once in a thousand years” rainfall, has caused devastating flooding that displaced hundreds of thousands of people and claimed the lives of at least 33 (Gan & Wang 2021). Similarly severe flooding occurred in western Germany and parts of Belgium in mid-July after 15 cm of rain fell in less than 24 hours (Cornwall, 2021). These events are just the most recent in a barrage of increasingly severe and unpredictable weather events over the past several years from Storm Imelda in 2019 to the Australia bushfires between 2019 and 2020.

According to World Weather Attribution (WWA), an international climate science initiative dedicated to quickly but thoroughly assessing risks and causes of extreme weather events, these global natural disasters are inextricably linked to climate change. For example, in their most recent publication analyzing the abovementioned heat-dome, the WWA concluded that reaching those extreme temperatures in western North America would be virtually “impossible without human-caused climate change” (WWA, 2021). After decades of science warning us of the dangers of climate change, its consequences are arriving at a pace that humanity does not seem ready for. With studies predicting the area affected by wildfire to increase by up to 118% in Canada by 2100 (Flannigan et al. 2005), how do we prepare for this new “new normal”?

Professional and cultural management and mitigation of wildfire

In the words of Natural Resources Canada: “Fire is a vital ecological component of Canadian forests and will always be present” (2020). However, climate change has led to conditions that cause earlier-catching, longer-lasting, bigger-burning, and ultimately more-devastating fires than ever before. However, like most other natural disasters, there is a complex intersection of factors at play exacerbating climate consequences, including: land clearing for agriculture; industrial-scale logging (including the subsequent planting of single-species plantations of trees which tend to be considerably more flammable than diverse natural forest ecosystems); fire suppression in fire-dependent ecosystems; and increasing human settlement in the wildland-urban interface (i.e. neighbourhoods bordering heavily wooded/forested areas, such as suburban bedroom communities). While we have the power to influence many of these factors to reduce the likelihood of out-of-control wildfires, to be truly effective, management prescriptions must strike a balance between maintaining local ecology and biodiversity while also protecting the built environment and human life.  

In Canada, a national educational program called FireSmart has been devised to educate homeowners on fire safety and mitigation, particularly in those wildland-urban interface neighbourhoods (FireSmart Canada, 2021). Due to ongoing fire suppression, many forests across Canada are carrying uncharacteristic “fuel loads” (i.e. a build-up of woody and other plant debris on the forest floor) that would otherwise have been reduced by natural fire regimes. In some forest types, this natural fire cycle means fires occur as frequently as once a decade, while in others they can occur as infrequently as once every few centuries (Noss et al., 2006). In addition to controlling fuel build-up, these natural fire regimes tend to play a significant role in: rejuvenating soils; adding complexity to the age and structure of a forest; influencing the movement of water and sediment across the landscape; and performing numerous other vital functions (Noss et al., 2006). Human disruption of these regimes has necessitated the initiation of such programs as FireSmart which focus on the removal of built-up fuel to prevent inevitable ground fires from becoming fast-spreading, high-intensity, and out-of-control crown fires. FireSmart has also developed protocols to guide other land-use management decisions, such as replacing fire susceptible plant species with fire-resistant ones and tree thinning, and pruning as shown in Figure 1. In some places, these protocols have been extended for use in protected areas and national parks.

Despite the growing adoption of FireSmart applications across Canada, its national scope tends to provide a very broad view of fire management and thus often fails to encompass local best practices for maintaining ecological integrity, resilience, biodiversity, and, in some cases, natural fire breaks. According to one American study, the complex ecology of many fire-dependent forest types defies this kind of “one-size-fits-all management prescription” (Noss et al., 2006, p. 481). These authors go on to say that “generalized [policies] of fire suppression [are] inappropriate given the documented negative ecological impacts of fire suppression during the 20th century” (p. 484). For example, many conifer stands in the boreal forest—which stretches across the country from Yukon to Labrador—have co-evolved with wildfire and are “characterized by high-intensity, crown [fires]” (Beverly et al., 2020, p. 1). As such, fire is an essential contributor to the maintenance of ecological balance in this forest type making the imposition of conventional fire management techniques a highly disruptive process. Further, although FireSmart and other alike management regimes, like FireWise in the USA, do tend to be effective in moderate weather conditions, some studies have found they make little difference when winds are high or conditions are exceptionally dry (Beverly et al., 2020).

As an alternative—or in some cases, an addition—to management regimes that reply on manicuring trees and understories, some studies suggest prescribed or controlled burns which are meant to get rid of built-up fuel to reduce uncontrolled wildfire risk (Vose, 2006). This practice has been undertaken by many Indigenous communities across what is now known as North America, and indeed across the planet, since time immemorial (Carroll, Cohn, & Blatner, 2004; Christianson, Mcgee, & L'Hirondelle, 2014). In addition to reducing damage by wildfires, these cultural burns also aim to promote the growth of traditional food and medicines and maintain the landscape for all species (Boutsalis, 2020). For example, many Coast Salish Nations used low-intensity ground fires to maintain Garry oak savannahs on Vancouver Island and the Gulf Islands in British Columbia to prevent catastrophic fire and encourage the growth of thick fields of purple camas flowers and other groundcover plant species.

What can you do?

Despite ample evidence that prescribed and cultural burns are an effective pathway to maintaining ecological health in fire-dependent ecosystems, this approach to fire management is generally ill-advised near communities where damage to infrastructure or risk to human safety is a factor. Though Indigenous Knowledge Holders generally have the experience and expertise to prevent these burns from becoming dangerous, climate change has irrevocably altered the way fires behave on most landscapes. So where does that leave us? FireSmart has been designed to protect the built environment and human safety, but often fails to enhance biodiversity, ecological integrity, or resilience. Alternatively, prescribed or cultural burns can protect ecosystem and cultural values, but climate change has made these practices less predictable—and further should only be implemented by Indigenous Knowledge Holders and other experts like fire ecologists. So, what are the options for people to protect their homes while also protecting the nearby ecosystems that make their homes beautiful and healthy places to spend time?

One of the most important things anyone can do to prevent damage from wildfire is to know and understand the ecosystem around their home to inform the best fire management strategy. For example, the Acadian Forest characteristic to the province of Nova Scotia and its surrounding perimeter is not a fire-dependent forest type. Wildfires are rare, with windthrow and insect infestation being much more common disturbances (Simpson, 2014). That said, Acadian forests have been heavily fragmented and converted, with the World Wildlife Fund calling it one of the most threatened forest types in Canada (Davis et al., 2001). As such, restoration of foundational species with low risk of pest infestation or disease like sugar maple, eastern white pine, or red spruce, to encourage old-growth characteristics is likely to reduce an already low fire risk.

Another approach to preventing fire from damaging infrastructure or becoming a danger to people is a lesson we have become very familiar with over the past two years: protection through herd immunity. In extreme fire risk areas like California, individual actions tend to be largely ineffective in preventing fire damage. According to American fire expert, Jack Cohen: ““If we don’t mitigate together, we will surely burn together” (Serna, 2019). Cohen suggests community-based solutions including neighbourhood-wide installations of sprinkler systems; widespread use of fire-resistant building materials; adoption of rainwater catchment on properties; and neighbourhood management of flammable debris. An added benefit of this approach is that new infrastructure like sprinklers and rain barrels can often be purchased and installed through bulk-buys, making it much more affordable than if purchased on an individual basis.

Undoubtedly, we are approaching a new era during which ecosystem management decisions are rife with uncertainty. When managing for fire, experts cannot simply rely on historic fire regimes as these have been disrupted by climate change. Further, understanding of ecological functionality has shifted with shifting climate conditions, and both fire and intensive management regimes (e.g. through forest thinning and understorey removal) may exacerbate climate change by releasing additional carbon into the atmosphere and altering ecosystem-wide carbon capture potential. Finally, in addition to considering human safety and infrastructure stability, consideration must be given to economic values, as fire can result in losses of woodlots and other lands managed for harvest. We are indeed entering a new normal, and as we do it will be essential to move away from business as usual, and toward a future based on community collaboration and holistic approaches to climate change mitigation and ecological protection.

The way forward is certainly together.

Resources & Additional Reading

Beverly, J.L., Leverkus, S.E.R., Cameron, H., Schroeder, D. (2020). Stand-level fuel reduction treatments and fire behaviour in Canadian boreal conifer forests. Fire, 3 (3), 35. DOI: 10.3390/fire3030035

Boutsalis, K. (2020, Sept 20). The art of fire: reviving the Indigenous craft of cultural burning. The Narwhal. https://thenarwhal.ca/indigenous-cultural-burning/

Carroll, M. S., Cohn, P, J., Blatner, K. A. (2004). Private and tribal forest landowners and fire risk: a two-county case study in Washington State. Canadian Journal of Forest Research, 34 (10), 2148-2158. DOI: 10.1139/x04-085

Christianson, A. Mcgee, T. K., & L'Hirondelle, L. (2014). The influence of culture on wildfire mitigation at Peavine Métis settlement, Alberta, Canada. Society & Natural Resources, 27 (9), 931-947. DOI: 10.1080/08941920.2014.905886

CBC News. (2021, July 22). Strong gusts forecast in B.C. and wind set to change direction, creating new challenges for wildfire crews. CBC News. https://www.cbc.ca/news/canada/british-columbia/bc-wildfires-july22-1.6112576

Davis, M., Gratton, L., Adams, J., Goltz, J., Stewart, C., Buttrick, S., Zinger, N., Kavanagh, K., Sims, M., & Mann, G. (2001). New England – Acadian forests. In T. H. Ricketts, E. Dinerstein, D. M. Olson, & C. J. Loucks (Eds.), Terrestrial Ecosystems of North America: A Conservation Assessment. Washington, DC: Island Press.

FireSmart Canada. (2021). What is FireSmart?. https://www.firesmartcanada.ca/what-is-firesmart/

Flannigan, M.D., Logan, K.A., Amiro, B. D., Skinner, W.R., Stocks, B.J. (2005) Future area burned in Canada. Climatic Change, 72 (1), 1-16. DOI: 10.1007/s10584-005-5935-y

Gan, N & Wang, X. (2021, July 22). Death toll rises as passengers recount horror of China subway floods. CNN. https://www.cnn.com/2021/07/22/china/zhengzhou-henan-china-flooding-update-intl-hnk/index.html

Natural Resources Canada. (2020). Fire ecology. https://www.nrcan.gc.ca/our-natural-resources/forests-forestry/wildland-fires-insects-disturban/forest-fires/fire-ecology/13149

Noss, R.F. Franklin, J.F., Baker, W.L., Schoennagel, T., & Moyle, P.B. (2006).  Managing fire-prone forests in the western United States. Frontiers in Ecology and the Environment, 4(9): 481-487. DOI:10.1890/1540-9295

Serna, J. (2019, Oct 3). Want to fireproof your home? It takes a village. Los Angeles Times. https://www.latimes.com/environment/story/2019-10-03/wildfire-defense-fire-proof-home-hardening-sprinklers

Simpson, J. (2014). Restoring the Acadian Forest: A Guide to Forest Stewardship for Woodlot Owners in the Maritimes. Halifax, NS: Nimbus Publishing.

Vose, J.M. (2000). Perspectives on using prescribed fire to achieve desired ecosystem conditions. Forest Ecology. https://www.srs.fs.usda.gov/pubs/ja/ja_vose011.pdf

World Weather Attribution. (2021, July 7). Western North American extreme heat virtually impossible without human-caused climate change. https://www.worldweatherattribution.org/western-north-american-extreme-heat-virtually-impossible-without-human-caused-climate-change/