Ross Andreson / AP
Smoke billows from a wildfire Sunday, Sept. 30, 2018, that briefly trapped eight hikers atop Lamoille Canyon, about 12 miles southeast of Elko.
Monday, May 15, 2023 | 2 a.m.
Some homeowners in the western United States have chosen to build in areas that are susceptible to wildfires for obvious reasons: The forest, with its beautiful trees and the unspoiled wilderness, are your backyard, said Nicholas Irwin, an assistant professor in the UNLV department of economics.
A recently published study in the Journal of Regional Science by Irwin and UNLV colleague Shawn McCoy, director of the Lied Center for Real Estate at UNLV’s Lee Business School, examines the wildfire risk and how it affects residential development in these fire-prone areas.
The study found that houses are springing up in the wildland urban interface — between unoccupied land and human development where structures bump against undeveloped wildland or vegetative fuels — faster than any place in the country. Researcher Katie Jo Black at Kenyon College in Ohio contributed to the findings.
In 1990, about 30.8 million housing units existed in such areas, the study found using U.S. Forest Service data. That grew to 44 million units 20 years later.
“The rate of growth of construction in these areas is just so fast,” Irwin said. “Even with whatever information you’re signaling, it’s just not enough to change the trajectory.”
Nevada had the highest percentage increase of homes in its wildland urban interface, at 208%. Of the state’s 1,281,018 housing units in 2020, 570,634 were located in the wildland urban interface, the study found.
And with the West in an extended drought, that’s a formula for wildfire disaster, the scholars said.
Take the 1,935-acre Caughlin Fire in southwest Reno in 2011 that destroyed about 28 homes, marred about a dozen others and caused $10 million in damages. It was the first of three significant recent wildfires.
The Reno Gazette-Journal reported that a total of 63 homes were destroyed or damaged in the three fires, including the Pinehaven Fire of 2020. All of the fires occurred in November — the result of power lines arcing in wind gusts up to 60 mph.
The scholars focused their research on how fires affect housing development, finding most homeowners underestimate their own risk, McCoy said. Wildfires are mere speed bumps that only slow development in those areas for a short, ultimately inconsequential time, he continued.
McCoy said a county might respond to increased development in a fire-prone area with an information campaign, but the study shows those measures don’t reduce development. They may also require an in-home sprinkler system as part of the build because there’s not a nearby fire station.
“Maybe development tamps down a bit, but it’s still increasing,” McCoy said.
The study
The research examined the rates of new single-family home construction in Colorado communities hit hard by wildfires that were FEMA-declared disasters, finding that fires reduced development — but didn’t slow it, McCoy said.
They found that a fire decreases the number of houses developed in a fire risk zone, but only for a short period of time. After five years, it’s business as usual.
Additionally, the study estimates that once construction picks back up in an area, it only takes developers about a month and a half to build the number of houses that went unbuilt during that five-year period of heightened fear following a fire.
McCoy compares it to when people are driving on a highway and encounter an accident. That causes them to briefly change their driving behaviors.
“There are some of the areas that are just sprawling, spiderlike areas across the state,” McCoy said. “Here, we have a situation where we literally have mountains and vegetation densities, and then a genuine interface in the middle.”
There were 92 FEMA-declared wildfires from 2000-15 in Colorado, including the 2012 Waldo Canyon fire that brought a loss of $477 million, they said.
Irwin said the development in areas of wildland urban interface — in states like Arizona, California, Colorado, Montana, Nevada and Wyoming — is putting more people and houses at risk. He stresses that “we need to rethink our patterns.”
The damage from those fires extends well beyond the people who chose to live in a fire-prone area, they said.
Embers can travel for miles from a wildfire, get sucked into an air vent and ignite an entire house. The smoke sickens people and exacerbates health issues like asthma in populations nowhere near the original blaze.
The researchers said they can infer that the results from their fire study would apply to other federally declared, exogenous natural disasters like earthquakes, landslides, floods and other sea-level hazards.
“Do we think homeowners may tend to understate those risks in the absence of a recent big shock? The answer is, our results suggest that they may,” McCoy said.
McCoy said if a fire-prone area goes for too long without burning, plant growth builds on the ground below the tree canopy, which serves as plentiful fuel for the next fire. The buildup also means more opportunities for lightning to strike and spark a fire.
“After these very aggressive fire suppression techniques, two things happened,” McCoy said. “Fires started to happen less frequently, but we also find that when they do happen, they’re not just fires, they are tree canopy mega crown fires. Fire severity, fire acreage burned and fire intensity have systematically shifted.”
Houses, he said, make even better fuel.
Flammable structures like houses in the wildland urban interface make fires much worse than undeveloped, tree-filled land would. A human presence also changes the dynamics, introducing new elements that can spark or worsen fires.
“When (people talk) about climate change, and climate-related risks, what most people really talk about is the risk posed to human populations,” McCoy said. “And what drives the presence of the human population? The answer is the real estate market.”
