Publication of analysis of learning facilitated by Marshall Fire

The scan is intended as an education and training tool for first responders.

BOULDER COUNTY, Colo. – A report released Thursday provides deep insight into the chaotic early hours of the Marshall Fire.

The report, known as facilitated learning analytics, was requested by the Mountain View Fire Department, Louisville Fire Department, and Boulder County. It was led by the Colorado Division of Fire Prevention and Control.

> Read the full facilitated learning analysis

The scan is intended to be an education and training tool for first responders, helping those who were directly involved in the response to understand what happened.

The report does not include the cause and origin of the fire, which is still under investigation by the Boulder County Sheriff’s Office.

Two people were killed in the Dec. 30 fire, which was the most destructive in Colorado’s history. The fire burned more than 6,000 acres in Boulder County, destroying 1,091 structures and damaging 179. It caused more than $2 billion in losses, making it by far the costliest fire in Colorado history.

The report details the heroism of first responders, some of whom went door to door on the path to the fire to save residents.

RELATED: Deputy Chief Receives Mountain View Fire Rescue’s First Medal of Bravery for Actions During Marshall Fire

“Thousands of emergency personnel and equipment poured in from neighboring counties, and a local Type 3 team attempted to establish control during the most catastrophic fire in Colorado history,” the report said. report. “Water ran out in some areas, and utility crews went to great lengths to keep the pressure on for firefighters. Propane tanks exploded to the scream of hurricane-force gusts, making the area look like a war zone. The efforts of these responders were nothing short of extraordinary, many working through the night and into the next day. Many local responders had homes within the perimeter of the fire.

RELATED: Water supply in Louisville, Superior nearly ran dry as firefighters battle Marshall Fire blazes

Chaotic communication

The report revealed that there were not enough radio frequencies for all the resources deployed to fight the fire.

The planned communications pattern was already in use for the so-called Middle Fork Fire, which was first reported around 10:30 a.m. that day in the foothills north of Boulder. This fire briefly threatened homes but was brought under control without causing any damage.

This earlier fire response meant Marshall Fire responders had to come up with a different setup on the fly.

RELATED: Some suburbs in the Denver metro area may be vulnerable to wildfires on high-risk days

Crews that came from other places had their own radio systems, and they didn’t always match.

“Rural departments arrived with VHF radios. Municipal departments often only had 800 MHz radios. Law enforcement worked directly with firefighters, but many relied on their home dispatch centers for tracking and information,” the report said.

The report Avista Adventist Hospital was evacuated more quickly because an emergency medical services chief used his home dispatch center in Broomfield County to request resources, rather than going through the mutual aid.

RELATED: Lesson learned by hospitals from Marshall Fire has already been used in other disasters

Wind effects

The report said the extreme drought was a major factor in the initial spread of the fire, noting that the winds that day were not unprecedented.

“Without the impacts of the drought and multiple other environmental factors that set the stage for the fire to ignite and spread, the wind event would have been a non-factor,” the report said.

However, according to the report, the winds were strong enough that if the fire had started sooner or the winds had lasted longer, there would have been even more destruction.

“The spread of the fire was halted in urban areas by a sudden wind shift recorded by line personnel at 12:15 a.m. on December 31, 2021 and by nearby weather stations as having occurred between 11:00 p.m. and 1:00 a.m.,” the report said. report. “This wind shift brought a cooler, more humid air mass as the rotor failed and the upflow enveloped the fire area. Even before this wind shift, responders noted that the The intensity of the winds had subsided, allowing them to begin to put out the fire more effectively. If the Marshall Fire had started earlier in the day, or if the downdraft winds had been sustained throughout the night, the extent of damage would have been greater, as distances between structures do not increase noticeably north and east of the final fire perimeter.”

The wind also made it difficult for the crews to find the fire at first, as there was no clear smoke plume.

“[A firefighter] went to secure his helmet with the chin strap, but by the time it took to move a hand from the top of the dome to the side, the helmet was ripped from his head and sent bouncing across the grass and into the misty smoke “said the report. “He never found him. The flames moved horizontally at a rapid spread rate and the water was ineffective. The front of flames had overtaken them in a garden. [The firefighter] was grateful they used the hose reel so they could retrieve the fully water loaded hose rather than having to abandon it as they repositioned themselves to chase the fire front.”

Spread of fire

The report found that houses were more likely to be destroyed if they caught fire due to indirect exposure than direct exposure. “Indirect exposure” refers to embers or flames from other burning buildings, while “direct exposure” refers to embers or flames from wild fuels.

“Of exposed structures, the most common outcome was no damage in directly exposed structures, occurring at 46.93%, but destruction was the most common outcome in indirectly exposed structures (46%),” according to the report. “Indirectly exposed structures were more likely to destroy than directly exposed ones (46.17% indirect exposure to destruction rate versus 41.27% direct exposure to destruction rate).

RELATED: Marshall Fire Losses Surpass $2 Billion

The report also revealed that wooden fencing played a role in spreading the fire.

“The Sagamore Subdivision and subdivisions along McCaslin Boulevard were directly exposed to some wildfire intensity, oriented spatially in the same direction, and had similar spacing between structures. The Sagamore Subdivision was completely destroyed, while the subdivisions along McCaslin Boulevard were largely untouched. Part of the difference appears to be in the distances between the wild fuels and the wooden fences next to the houses where they existed,” the report states. “Both neighborhoods had wooden fences around many houses on their outskirts, but houses just east of McCaslin Boulevard had a distinct advantage, as a small area (usually 30–50 feet) of manicured lawn lay beside these fences. Small embers associated with spotting wild herbs go out very quickly, with those that land often only being able to ignite small one-hour fuels such as dried herbs. For this reason, combined with the effect that McCaslin Boulevard itself had in slowing, but not stopping, the overall spread of fire, the lower intensity and reduction in staining produced by a small area of natural fuels next to manicured lawns were not sufficient to catch the wood. burning fences and the houses in this area are largely intact. »

From June: Marshall Fire’s after-action report lists dozens of recommendations to help prepare for the next emergency

SUGGESTED VIDEOS: Marshall fire blanket

Comments are closed.