Posts Tagged: Wildfire
[This story was originally published Oct. 4, 2021, and updated Dec. 21, 2022]
In 2018, the Camp Fire destroyed nearly 19,000 structures in Northern California, including most of the town of Paradise. The structures left standing by the conflagration provided researchers an opportunity to investigate how housing arrangement – such as the size of the lot, the distance to a neighboring home, and surrounding vegetation – influenced which homes survived. They also looked at whether changes to the California Building Code in 2008, through the addition of Chapter 7A, improved the chances of homes built in the wildland-urban interface to withstand wildfire.
Both housing arrangement and surrounding vegetation likely influenced the survival of homes during an extreme wildfire, according to new research from the USDA Forest Service and the University of California Agriculture and Natural Resources analyzing the Camp Fire aftermath, which will be published Oct. 3 in the journal Fire Ecology.
“Our team found a reason for hope and information that can help Californians, building contractors and policymakers better prepare for future fires,” said co-author Yana Valachovic, University of California Cooperative Extension forest advisor.
The 2008 code, which applied to the city of Paradise, requires the installation of vents that resist flames and embers and other elements that help harden a home to wildfire. This chapter of the California Building Code added requirements for construction materials to California's existing two-zone fuel and vegetation modification guidance, known as “defensible space,” which applies to the vegetation and fuels out to 100 feet from a home.
The researchers found that the age of the home was a significant factor in predicting survival. But the key year wasn't 2008. Improvements in performance happened earlier. Only 11% of single-family homes built in or before 1996 survived, compared with 40% for homes built after 1996. Older homes were, on average, placed closer together and had more overstory tree growth near the home. Overall, the greater the distance between structures, the lower the likelihood of a home being destroyed by the Camp Fire. And the less overstory tree canopy cover, the higher the likelihood of a home surviving.
During a wildfire, structures can be threatened by the flaming front of the fire and by embers that are lofted ahead of the fire and land on fuels such as vegetation or mulch next to the house, igniting new fires. Embers can also enter homes through open windows or vents. Heat radiating from adjacent burning buildings or vegetation can also impact home survival.
In 2022, during a visit to Laguna Niguel after the Coastal Fire, Valachovic saw that defensible space had prevented flames from reaching homes. However, some houses had burned from the inside out after embers penetrated attic vents and ignited combustible materials.
“Despite the unpredictable nature of wildfire, strong associations with home arrangement and overstory vegetation cover indicate home survival is at least somewhat predictable,” said lead author Eric Knapp of the USDA Forest Service. “The silver lining is that this also suggests steps can be taken to substantially improve the odds of homes surviving a wildfire.”
One of the biggest drivers of home loss in the Camp Fire was the heat radiating from the large number of structures that burned. Over 73% of homes destroyed in Paradise had a structure burn within 59 feet. The distance to the nearest destroyed structure or total number of destroyed structures within 328 feet was a primary predictor of home loss.
“Exposure to the heat of a nearby burning structure can break glass in a window, for example. Once the glass is broken, embers or flames can enter the house,” said co-author Steve Quarles, emeritus UC Cooperative Extension advisor and retired chief scientist for the Insurance Institute for Building & Home Safety.
This finding suggests that denser developments, built to the highest standards, may protect subdivisions against radiant heat from a vegetation fire, but density may become a detriment once buildings ignite and radiant heat loads increase as well as the increased potential for direct flame contact.
“This research suggests a strong neighborhood effect, where the condition and proximity of an outbuilding or a neighbor's home can have a significant influence on a building's survival given the radiant heat exposure from a neighboring building burning,” Valachovic said.
Tree canopy cover was also associated with home loss, with a higher probability of home survival where tree cover was moderate or less.
“Trees provide shade, which is important where summers are hot. But to have the amenities trees provide without undue fire hazard, the key is to clean up the leaves and dead wood trees produce,” said Knapp. “This includes keeping roofs, gutters, garden beds adjacent to the structure and spaces under attached decks, free of leaves.”
The researchers detected no significant increase in survival for homes built from 2008 to 2018, under the new building code, compared to homes constructed during an equal time period, 1997 to 2007, immediately preceding the adoption of the new code. Houses built during the last two decades resisted wildfire better than older homes, indicating an overall improvement in common construction standards and the performance of building materials.
“It is important for Californians to understand that homes and immediate surroundings need to be well-maintained to resist embers, survive extended radiant heat exposures and minimize direct flame contact,” Quarles said. “Fortunately, all building codes get better with time and Chapter 7A is no exception – Californians have benefited from it. California's Building Code is reviewed every three years, and it is evolving as new knowledge becomes available based on research and post-fire assessments.”
To enhance wildfire protection at the neighborhood scale, the researchers recommend coordinating efforts with neighbors.
“Because ember ignition of one house can put neighboring houses at risk, it is critical that fuel reduction happens at a community scale. Living with fire means doing all things possible to prevent one's house from catching fire,” said Valachovic.
There are simple actions that homeowners can take to protect their homes.
“From retrofitting with vents that resist ember entry or using tempered glass windows, to the simple things, like not placing bark mulch or woody plants next to homes, and using gutter guards to minimize leaf and needle accumulation in gutters, all will improve the chance of home survival,” Quarles noted. “It is a matter of how we choose to live in this environment.”
“Housing arrangement and vegetation factors associated with single-family home survival in the 2018 Camp Fire, California” by Knapp, Valachovic, Quarles and Nels G. Johnson is published in the journal Fire Ecology at https://fireecology.springeropen.com/articles/10.1186/s42408-021-00117-0.
For more information:
- Steps for hardening houses against wildfire can also be found at the Fire in California website: https://ucanr.edu/sites/fire/Prepare/Building.
- Reducing the vulnerability to buildings to wildfire: vegetation and landscape guidance https://anrcatalog.ucanr.edu/pdf/8695.pdf
Despite recent rains, fire remains a danger across California, as there's still plenty of time this fall for grass, woody debris and other flammable material to become dry and ignite.
“The smaller the fuels – pine needles, grass, and small twigs – the faster they can dry out, meaning they will be ready to burn again a few days or weeks after a large rainstorm,” said Susie Kocher, a UC Cooperative Extension forestry and natural resources advisor for the Central Sierra, urging residents to take steps to prevent or limit potential fire damage.
When it comes to “home hardening” and essential wildfire preparations in this age of drought and climate change, not every project requires a bank-breaking budget and an army of contractors.
There are small – but significant – home and landscaping improvements that most people can complete by themselves during a single weekend, with a quick run to the hardware store and some basic planning and safety precautions.
“There are a lot of factors that play into your home's vulnerability to ignition; small changes and upgrades can help reduce some of that risk for people living in high wildfire risk areas,” Kocher explained. “The bigger projects like replacing windows and roofs are very important, but there are definitely smaller projects that people can tackle right away at lower cost that also reduce risk. The main goal of these actions is to reduce the risk that wildfire embers can ignite your home.”
Kocher recommends these five measures as simple but crucial ways to bolster your home's wildfire resiliency.
Clean debris from your roof. Because of its expansive surface, the roof is the most susceptible area of your house to embers. Removing accumulated leaves and needles is especially important if you have a “complex roof” with dormers or other elements – that's where embers gather, too, and could come in contact with flammable siding. (And while you're up there, give those gutters a good swabbing.) Learn more about protecting your roof and gutters.
Install metal flashing in vulnerable spots. Replacing all your siding with noncombustible material can be pricey, but a more manageable task would be adding corrosion-resistant metal flashing to select areas: roof-to-wall intersections, the place where the chimney comes out of the roof, and the edge where the deck meets the house. Learn other ways to shore up your siding.
Remove debris from between the boards of your deck and fence. Embers can ignite leaves and needles stuck between the boards, so be sure to keep those gaps clean and clear. Learn additional steps to harden your deck and prepare your fence.
Take out all vegetation (alive or dead) within five feet of your home. Creating defensible space immediately next to your home is a top priority, so be sure there's nothing combustible within this “Zone Zero.” Plants, mulch, woodpiles, wicker furniture or anything that can catch fire should be removed. Learn what to do in the other “zones” as you move farther from your home.
Inspect vents and upgrade to finer mesh screens. Install or swap in noncombustible, corrosion-resistant metal mesh screening that is at least 1/8” (1/16” would be even better but requires more frequent maintenance). These screens help prevent embers from entering your attic and crawl space. In addition, put together some vent covers that can be deployed if you have time before a wildfire arrives. Learn other ways to reduce vulnerability of vents.
For more in-depth explanations and next steps, Kocher suggests visiting the UC ANR wildfire website (https://ucanr.edu/sites/fire/Prepare) and reviewing this home retrofit guide (https://bit.ly/3RaL54u).
UC ANR hires more fire advisors to address growing threat to California communities
Bringing more expertise to more places across the state, University of California Agriculture and Natural Resources continues to hire fire advisors to help communities prepare for one of the most devastating climate-fueled threats.
With wildfires a constant danger as drought grips California, five highly skilled UC Cooperative Extension experts have joined the organization since early May:
- Katie Low, statewide fire coordinator (and also serving Nevada and Placer counties)
- Alison Deak, fire advisor serving Mariposa, Fresno and Madera counties
- Tori Norville, fire advisor serving Sonoma, Napa and Marin counties
- Barb Satink Wolfson, fire advisor serving Monterey, San Benito, Santa Clara and Santa Cruz counties
- Luca Carmignani, fire advisor serving Los Angeles and Orange counties
These positions – as well as other recent additions in agriculture and natural resources fields – are made possible by California's commitment, as reflected in the state budget, to improve the lives of residents in the face of a changing climate.
This robust team of fire experts provide broad knowledge and practical advice on a wide range of topics, including fire hazard mitigation, fire ecology, prescribed fire, wildland fire research, forest and wildlife management, and climate change effects.
Although their specific areas of expertise vary, all the new fire advisors are dedicated to helping residents and community groups across California become more fire-aware, adapted and resilient. They share vital information on how Californians can prepare homes, landscapes and property for wildfire.
First, she will coordinate and partner with UCCE fire advisors throughout California to develop and deliver wildfire-related science and outreach materials for a wide range of communities across the state. Low said encouraging diversity in the network of fire experts and engaged communities will be crucial.
“One of my goals is to help build and maintain a diverse and inclusive community of fire and natural resource professionals,” she said.
Based at the UCCE office in Auburn, Low also will collaborate with local natural resource professionals and residents in Nevada and Placer counties on projects that bolster community and ecosystem resilience to wildfire and climate change.
“I look forward to working with community groups, land managers and scientists to implement viable fire-resilient management strategies for ecosystems in the region and statewide,” Low said.
Equipped with bachelor's degrees in geography and ecosystems management and forestry, as well as a master's in forestry, all from UC Berkeley, Low brings to UC ANR a wealth of knowledge and a variety of experience.
As a fire and forest ecologist, she studied the impacts of fuels-reduction and forest-restoration treatments on Sierra Nevada mixed-conifer forests. Low also worked as operations coordinator for the California Outdoor Engagement Coalition, and as a forestry aide for California Department of Forestry and Fire Protection's Forest Biometrics Program.
Low can be reached at 530-889-7385 and email@example.com; follow her on Twitter @lowseverityfire.
Her role as fire advisor will include promoting the use of prescribed fire to help restore fire adapted landscapes. She will also prioritize community education, applied research and partnership building efforts that are based on scientifically informed ways to help communities mitigate, prepare for, and recover from wildfire.
Originally from northeast Ohio where there are no wildfires according to Deak, it was not until she moved to Colorado for college that she learned of their impact.
When the 2012 Waldo Canyon Fire occurred, Deak felt like her playground was burning down so she acted. She began volunteering with the wildfire recovery effort and her career into fire science took off from there.
Deak earned a bachelor's in geography and environmental studies from the University of Colorado in Colorado Springs and master's degrees in geography and nonprofit management from the University of Oregon.
Before moving to California and joining UC ANR, Deak worked as a wildland firefighter with the United States Forest Service and Bureau of Land Management.
When asked what she is looking forward to most, Deak shared that she is passionate about increasing diversity in the fire science field and, particularly, empowering more women to join. She is eager to help community members prepare for wildfire and mitigate fire risk in a safe and competent manner.
Deak is located at the UC Cooperative Extension office in Mariposa County and can be reached at firstname.lastname@example.org.
In this capacity, Norville will work with residents and organizations within the wildland-urban interface to encourage and cultivate fire-adapted communities. She aims to provide education and outreach on home hardening, defensible space and the importance of forest and fuel management on the landscape.
While pursuing her bachelor's degree in forestry and natural resources at Cal Poly San Luis Obispo, Norville became interested in “disturbance ecology” – how factors such as disease, insects and fire affect landscapes and environments.
“Many of the forest health problems we are seeing are stemming from a lack of disturbance, which traditionally was fire,” Norville said.
Her understanding of fire and its effects deepened during her master's degree studies in forestry science (also at Cal Poly SLO), as well as through her seven years with CAL FIRE at the Jackson Demonstration State Forest in Mendocino County. She worked as the Registered Professional Forester for its Timber Sales Program, and then the Research and Demonstration Program.
Norville's firsthand experiences from the past few fire seasons have helped shape her goals and approach. She hopes to “work holistically with disturbances” – specifically fire – on the landscape to foster healthy forests and ecosystems that are adaptable and resilient, while also researching the environmental and social aspects of fuel-reduction projects and prescribed fire.
“Hopefully, I can begin to change the perception of fire from something we need to fear, to something we respect,” she said.
Norville, based at the UCCE office in Santa Rosa in Sonoma County, can be reached at email@example.com.
Barb Satink Wolfson
Barb Satink Wolfson began in her role as UC Cooperative Extension fire advisor for Monterey, San Benito, Santa Clara and Santa Cruz counties on June 30.
Her primary responsibilities include wildland fire-related research and outreach for the Central Coast region, while building trust, strong partnerships and collaborative relationships within both professional and non-professional communities.
Satink Wolfson earned her B.S. and M.S. in forestry from Northern Arizona University, and brings to UC ANR more than 20 years of fire-research and outreach experience in Arizona. Her favorite job, though, was working as a backcountry ranger in Yosemite National Park during her undergraduate years.
In her new role, Satink Wolfson hopes to address some of the questions behind the use of prescribed fire in a variety of ecosystems (such as coastal prairies and oak woodlands), and help all Central Coast communities build resilience to wildland fire so residents can live safely within fire-adapted landscapes.
Satink Wolfson, based at the UCCE office in Hollister, can be reached at firstname.lastname@example.org.
Prior to joining UC ANR, Carmignani was a postdoctoral researcher in the Berkeley Fire Research Lab at UC Berkeley. His research has focused on fire and combustion applications, from wildland fires to material flammability.
He earned his Ph.D. in engineering sciences from the joint doctoral program between UC San Diego and San Diego State University after obtaining his bachelor's and master's degrees in aerospace engineering from the University of Pisa in Italy.
UCCE forest advisor helps landowners, community groups determine best project options
As Californians prepare for another year of drought and an anticipated intense fire season, landowners and organizations across California have been working to reduce forest fuels – flammable woody material – that can endanger their properties and communities.
For many of them, however, their urgent efforts hit a sizable speed bump: a massive rulebook that describes, amid a thicket of other information, the permits required before people can treat or remove fuels – as well as a litany of attached requirements, restrictions and stipulations.
“The California Forest Practice Rules are 410 pages, in font size 6,” said Yana Valachovic, UC Cooperative Extension forest advisor for Humboldt and Del Norte counties and registered professional forester. “Trying to figure out what permit vehicles make sense in the rulebook is not easy even for the experienced professional forester.”
To assist private landowners and community groups in deciphering the rules and determining their most cost-effective options, Valachovic took the lead in writing a new guide, “Planning and Permitting Forest Fuel-Reduction Projects on Private Lands in California,” available as a free resource in the UC Agriculture and Natural Resources catalog.
“We tried to create a system where all the permits are laid out side-by-side, and put in a decision tree framework to help make it easier,” said Valachovic, highlighting the publication's tables that break down the project goals and parameters a permit applicant should think about when weighing their choices.
Considerations include whether the project is pre- or post-wildfire, the location and dimensions of trees targeted for removal, the conditions of the site before and after the project, potential time limits, commercial options, and, crucially, budget constraints – given that the permitting process could comprise up to one-third of total project costs.
A primer for planning and preparation
Chris Curtis, the unit forester for CAL FIRE's Humboldt-Del Norte Unit, said that he and his colleagues are grateful for this new tool and plan to use it as an “over the counter” handout for community members. He added that the charts summarizing timber-harvesting regulations and possible funding sources are especially helpful.
The publication helps prepare the landowner or community entity (such as Resource Conservation Districts, Fire Safe Councils or other concerned groups) for the types of questions that might come up in preliminary planning conversations with a registered professional forester or RPF.
Just as a homeowner would talk with a contractor before tackling a construction project, landowners and community groups must consult with an RPF, Valachovic said. RPFs have the specialized knowledge of forest practice rules and regulations related to water, air quality and endangered species protections, and the license to file the permitting documents.
“That's what I do in my job: Landowners come to me and we start talking about goals and objectives,” she said. “We start thinking about potential timelines – which goals are short-term, which are long-term – and how we can put an operational plan together to help those landowners achieve their goals.”
Long-term projects, short-term actions
Among the many practical tips outlined in this guide, Valachovic emphasized one in particular: for landowners dipping their toes into fuel reduction for the first time, keep the project “simple and realistic.”
In the short-term, however, Valachovic stressed that the extremely dry conditions across the state make it imperative for Californians to harden their homes, manage the fuels (i.e., landscape plants, stored wood, tall grass, etc.) immediately adjacent to their homes, and devise and review family emergency plans; see UC ANR's Wildfire Preparation page for detailed information and resources.
“There are a lot of immediate actions that people can be doing this year to help mitigate their wildfire risks and prepare for the unexpected,” she said.
In addition to Valachovic, co-authors of “Planning and Permitting Forest Fuel-Reduction Projects on Private Lands in California” are Jared Gerstein of BBW Associates and Brita Goldstein, UCCE staff research associate in Humboldt and Del Norte counties; both are registered professional foresters./h3>/h3>/h3>
Pilot program in Santa Barbara County shows promise for bolstering resilience
After a rash of wildfires across Southern California in 2003, many counties, cities and neighborhoods adopted Community Wildfire Protection Plans to improve their preparedness and fire response. But Rob Hazard, fire marshal for Santa Barbara County, has noticed that CWPPs and resources are unevenly distributed across areas at high risk of wildfire.
“Communities that are more affluent, more white, they are the ones that end up getting the grants, they're the ones that end up getting the projects to mitigate risks,” Hazard said, “whereas more disadvantaged communities…often don't have the organization to make that happen, or maybe it's not the most pressing issue of the moment.”
Mapping those underserved communities – and ensuring they have a more equitable share of attention – are some of the goals of a new, more comprehensive approach to wildfire, currently being piloted in Santa Barbara County. This “Regional Wildfire Mitigation Program” aims to fill in many of the gaps left by CWPPs, which tend to have a more narrow focus on fuel reductions for a specific locality.
“They certainly have their role and benefits, but CWPPs are pretty limited in scope,” said Max Moritz, University of California Cooperative Extension's statewide wildfire specialist. “They're really focused on modeling and prioritizing fuel breaks, and they leave all of these other aspects of our fire problem – our vulnerabilities, our potential losses – unaddressed.”
Moritz is the lead author of a recently published research article that describes the Regional Wildfire Mitigation Program's three key areas (or “domains”) for wildfire mitigation work: the built environment (pinpointing and addressing needs in buildings/infrastructure), landscape (creating buffers through land use policies and management choices), and community (educating the public on home hardening and other issues).
“It's this holistic approach that combines all of these elements, and each one of those elements speak to each other – they can't be independent,” said Hazard, a study co-author.
Seeking a better way
After the Thomas Fire devastated the region in 2017-18 and triggered deadly mudslides in Montecito, Moritz – an adjunct professor at UC Santa Barbara's Bren School of Environmental Science & Management – sought more encompassing risk mapping and mitigation solutions that could complement CWPP efforts.
He got together with Hazard, who began his career as a “hotshot crew” firefighter with the U.S. Forest Service and has been with Santa Barbara County Fire Department for nearly 25 years.
“Both of us believe: Yes, it is home hardening – but it's also defensible space, but it's also some fuel treatments, but it's also some prescribed fire, but it's also some agricultural belt (to create a buffer),” said Hazard. “We looked at it objectively, and in every community in Santa Barbara County there's something that either works – or doesn't.”
By the end of the pilot program along the south coast of Santa Barbara County, the team hopes to have refined a “decision support system” that other communities across the state – and perhaps around the globe – could use. The framework would incorporate their localized risk assessment data and conditions to help generate lists of prioritized projects across the three “domains” of wildfire mitigation.
The ability to adapt to new data and continual changes in ecosystems, communities and climate is another advantage of the RWMP. Unlike a “plan” that tends to be a one-off with a defined start and end date, this wildfire mitigation “program” is designed to pivot and evolve as conditions change. The goal is to motivate and guide implementation of risk mitigation activities in each domain.
“The program is a living program, so it's not going to be some PDF that sits on a server somewhere,” Hazard said.
One of the early lessons from the RWMP pilot has been that – aside from funding – a crucial factor in maintaining the momentum of a wildfire mitigation program is the presence of a dedicated group of community members.
“In each community, we'll need a group that is ready to take this on and spearhead it and run with it,” Moritz said. “In many communities, that will probably be the Fire Safe Council.”
Building ‘Firewise' communities
Local Fire Safe Councils are “grassroots, community-led organizations that mobilize residents to protect their homes, communities and environments from catastrophic wildfire,” according to the California Fire Safe Council.
And while Moritz, Hazard and other experts serve on the volunteer Board of Directors for Santa Barbara County Fire Safe Council, they soon realized that they needed to hire staff to perform the “community domain” work of educating and reaching out to residents.
A $5 million grant from the National Fish and Wildlife Foundation for the RWMP project helped build the capacity of the council, which hired its first staff member, Anne-Marie Parkinson, last fall.
“A lot of people underestimate how important it is to have community activists or leaders who take on the role and responsibility of organizing people, being the point of contact, rallying people to do activities or work days,” said Parkinson, a graduate of UCSB's Bren School and a co-author of the RWMP study.
Parkinson has been working to get communities recognized by Firewise USA, a program of the National Fire Protection Association to organize residents in bolstering wildfire preparedness and reducing risk.
Although she has been encouraged by the awareness and activism among the community members she has met, Parkinson also hears from residents about the need for more resilient power and communications networks – concerns that could be better addressed by consolidating those requests with a regional approach.
“As we work with more and more communities, you can start to map which communities want better telecommunications, and which communities would benefit from a fuel break around them, and then we could write a grant that benefits five communities, instead of one small grant for one community,” Parkinson said.
There are many communities in fire-prone environments that are in need of help, and climate change makes their situation increasingly urgent, Moritz said, and a new and comprehensive framework – the RWMP – now exists for assessing and mitigating multiple risks.
“Every community has its own unique fire hazards and its own unique spatial layout of neighborhoods and vulnerabilities inherent to those neighborhoods,” he said. “But despite the uniqueness of each community and each region, I'm hoping this will provide a somewhat systematic way to approach making progress and mitigating a whole suite of risks.”
Other authors of the article are Kelly Johnston, Molly Mowery and Katie Oran of the Community Wildfire Planning Center; Marc Mayes of Spatial Informatics Group-Natural Assets Lab and UC Santa Barbara Earth Research Institute; Graham Wesolowski of Spatial Informatics Group-Natural Assets Lab; and David Schmidt of Spatial Informatics Group. The article is published in Frontiers in Forests and Global Change at https://www.frontiersin.org/articles/10.3389/ffgc.2022.848254/full.