Continued from February 2024 (See PART 1 by Clicking Here)
2. LOCATION OF THE FIRE'S IGNITION POINT AND EXPECTED FOOTPRINT
Easy Escape Route: Human-start fires typically occur near roads so escape routes are accessible to the fire starter. The location of the Washburn Fire’s beginning, according to the LA Times and NPS maps, indicate that it started “along a trail on the edge of the Mariposa Grove, just downhill from the road used by shuttle buses to ferry tourists from a parking lot.” This location was about ¼ of a mile (i.e., 220 feet) from the shuttle drop-off point at the Grove, allowing any person a quick “getaway” without being noticed by hurrying up the trail to the return shuttle shelter, board a shuttle within 10-15 minutes, return to the Welcome Plaza, retrieve one’s vehicle, and exit the parking lot.
High Fuel-Load and Uphill Topography: The precision of the fire’s starting point could not have been more expertly selected for the fire’s ignition and quick spread, which supports the intentionality of the fire’s beginning. As one Wildland Fire Training module notes, “As you’ll discover, topography, fuel, and weather are the main culprits to watch.”
The person who ignited the Washburn Fire appears to have been aware of this basic training information. First, although the area around Mariposa Grove and Wawona has a long history of prescribed burns and fuel reduction strategies, the starting point occurred near the Washburn Trail in a high fuel-load area “without any known fire history, characterized by abundant dead and downed fuels and dense ladder fuels. These forest conditions are the legacy of almost a century of fire suppression and the horizontal and vertical fuel continuity facilitated rapid fire spread, intense fire behavior, and high resistance to control.” (Hankin, et al 2023) Choosing this area to ignite the Washburn Fire guaranteed the fire would take hold and spread rapidly.
Secondly, the topography of the ignition point would also provide directionality to the fire. The fire began where the Washburn Trail crosses a small creek bed that descends from a south-facing canyon with steep slopes. In the same training module for firefighters noted above, it states, “In the Northern Hemisphere, the slopes facing south receive direct sun rays and become hotter than the slopes facing any other direction. The higher temperature on the southern exposures results in lower humidity, rapid loss of fuel and soil moisture, and drier, lighter flashy fuels such as grass. All of these things add together to make southern slopes more susceptible to fires than northern slopes.”
The rapid elevation gain and canyon walls would cause “wind channeling” to quickly move the fire upwards since, as the Training Module notes, “fires usually move faster uphill than downhill, so the steeper the slope, the faster a fire moves.” Again, this is basic fire knowledge that directed the fire’s growth (see MAP of starting point above).
By the time the fire reached the Mariposa Grove Road, its intensity and flame height would allow it to cast embers across the Mariposa Grove Road, producing spot fires that would continue the fire’s movement northward into the high fuel-load portion of the forest. As Hankin, et al (2023) noted, “Tree torching from the point of ignition was casting embers long distances to ignite spot fires mid-slope, deep within an untreated forested area with limited fire history. These spot fires quickly developed into head fire running upslope and exhibited extreme fire behavior, with short crown runs and flame lengths exceeding 60 m.”
A Predictable Burn Path: Knowing the fire history of the two primary resources in the area, Mariposa Grove and Wawona, would allow an educated arsonist to virtually predict the ultimate footprint of the fire. Hankin, et al (2023) states that “The Mariposa Grove was one of the first areas of Yosemite to be treated as part of its prescribed fire program . . . and remains a focal area for Yosemite fire and fuels management. Over 1,821 hectares have been treated by prescribed fire in the Mariposa Grove and surrounding areas near the community of Wawona since 1970.”
Additionally, biomass removal along the Wawona Road (Hwy 41) completed in 2021 and 2022 along with prescribed burns allowed firefighters to provide backfiring to reduce combustible material along the western boundary of the fire. All of this biomass removal and prescribed burns provided a corridor of untreated forest buffeted by areas of prescribed burns and fuel reduction. The selection of the fire’s starting point would lead the fire through this corridor.
Finally, the 2017 South Fork Fire also acted as a buffer of reduced biomass along the north side of the Merced River as the fire moved eastward into Yosemite’s wilderness. Looking at the map below, even a layperson could offer a reasonable guess of the fire's burn direction based on the area's history of prescribed burns, biomass removal, and natural fires.
The NPS map below right shows a portion of the actual footprint of the Washburn Fire.
3. MOTIVATION FOR STARTING THE WASHBURN FIRE:
The theme of this three-part series asks the question, ‘Was the Washburn Fire started intentionally by an “Insider,” that is, some- one closely associated with Yosemite National Park’?’ I would not ask the question frivolously given the seriousness of the issue.
A sufficient level of suspicion would need to exist based on unique circumstances and events that appear to coalesce together. I believe such circumstances and events do exist. Nevertheless, I acknowledge that this inquiry lacks one of the most important aspects of a thorough fire investigation: Interviews.
Interviews with individuals who may have specific knowledge, especially in the case where a crime such as arson has been committed, produce additional leads by uncovering fire-linked relationships, confirmation or non-confirmation of hunches, exposing personality characteristics, agendas, and desires of potential suspects, and uncovering knowledge only the fire-starter(s) might have about the unique fingerprint of the Washburn Fire.
This unique fingerprint of the Washburn Fire, which includes its start, location, and progression as noted above and in Part 1, becomes the primary “lead” that develops the list of interviewees. Logically, then, the next question to ask would be, ‘Who could benefit by igniting a fire in such a cherished setting as Yosemite National Park?’ Answering that question narrows the range of possible arsonists with their fingerprints on the fire.
So, I will address two potential areas of inquiry. First, I will briefly look at research on fire-fighting arsonists. Secondly, I will further develop the idea that specialized knowledge guided the decision of where to start the fire, and how a person or persons closely associated with Yosemite National Park could be the holder of that knowledge.
The following serves merely as an inquiry into possibilities without formulating any specific conclusions. Readers may come to their own conclusions.
Possible Insider # 1: The Firefighter Arsonist: The NPS cites a study that indicates “nearly 85 percent” of wildland fires in the United States are caused by humans. That general statistic would include the least suspected offenders: firefighters. As hard as it might be to believe that a firefighter, trained to prevent and douse fires, would start a forest fire, it does happen.
Research by the FBI in the mid 1990s indicated that “75 firefighters were found to be responsible for 182 fires across seven US states and one Canadian province” (Cited in the US Fire Administration (USFA) Special Report dated January 2003, page 3).
Why would a firefighter start a fire? The issue is complex, but the USFA Special Report listed three primary motives that can be associated with the firefighter arsonist. They include: 1. The need to be seen as a hero, 2. To obtain experience extinguishing fires, and/or 3. To earn extra money.
As noted in Part 1 of this article, a contingent of firefighters were receiving training in Wawona on the day the Washburn Fire started. Their presence mathematically increases the chances that one of them, either acting alone or at the behest of others, started the fire. A lunchtime break would allow an escape to the Washburn Trail to ignite a fire that would put those firefighters in motion rather quickly. The Washburn Fire would allow for any of the three motives listed above to see fulfillment during the month-long fire fight. No fires were burning in Yosemite at the time and the fire season had commenced only eight days earlier.
Interviews with all persons attending the class would be a part of my investigation if I had been tasked with that responsibility.
Yet, the notion of one firefighter chasing after “hero” status, earning extra money, and needing the experience and excitement of fighting a fire in Yosemite seems to stretch the imagination given the setting and resources at risk (i.e., the town of Wawona and the Mariposa Grove of Giant Sequoias). More must be involved to make this a credible hypothesis. The precision of the fire’s start location, its predictable progression, and its final burn footprint suggest that someone possessing more sophisticated knowledge of the terrain in which the fire burned contributed to the planning of this event. In other words, a firefighter may have been working in tandem with someone closely associated with Yosemite (e.g., a National Park Service (NPS) employee).
Robust interviews would aid in revealing the kind of information that would or would not support the hypothesis noted above. Lacking such interviews, I will instead utilize a report by researchers from the NPS submitted for publication just 19 weeks (January 30, 2023) after an early autumn rain (September 20, 2022) finally extinguished the Washburn Fire. An assumption that this research was not generated by Artificial Intelligence (AI) accompanies the following.
Possible Insider # 2: NPS Employee(s) or Associate(s):
-- Continued Next Month In Part 3 --
REFERENCES
Hankin, L.E., Anderson, C.T., Dickman, G.J. et al. How forest management changed the course of the Washburn fire and the fate of Yosemite’s giant sequoias (Sequoiadendron giganteum). fire ecol 19, 40 (2023). https://doi.org/10.1186/s42408-023-00202-6
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