Jun 8, 2023 - Energy & Environment

Officials: Colorado's Marshall Fire caused by residential embers and detached power line

Burned cars sit in front of a home decimated by the Marshall Fire on January 4, 2022 in Louisville, Colorado. Photo: Michael Ciaglo/Getty Images

The 2021 Marshall Fire — the most destructive wildfire in Colorado history — started off as two fires, which combined to create the massive flames, Boulder County officials said Thursday.

Details: Boulder County Sheriff Curtis Johnson said during a press conference the first fire started at a residential property on Dec. 30, by embers leftover from about a week earlier during an attempt to dispose scrap wood and tree branches.

  • The second fire started just south of the Marshall Mesa Trailhead about an hour later, likely from "hot particles" from an Xcel Energy detached power line.

Yes, but: Johnson said it's not clear when the two merged.

  • He added that underground coal mine fires in the area cannot be ruled out as potential causes for the second event.

Why it matters: The findings provide a clearer picture of how the Marshall Fire started before developing into a catastrophic event, tearing through residential subdivision and crossing over a highway in the county.

What they're saying: "With every home that burned that day, people lost everything — all their possessions, family heirlooms, were turned to ash," Johnson, who grew emotional as he spoke, said Thursday noting he lost his home in the fire.

The other side: Xcel Energy said in a statement on Thursday it "strongly" disagrees with the suggestion its power lines caused the second ignition, adding maintenance records reviewed by the company showed the system there was properly maintained.

  • "Xcel Energy did not have the opportunity to review and comment on the analyses relied on by the Sheriff’s Office and believes those analyses are flawed and their conclusions are incorrect," the statement reads.

Context: The wildfire killed two people — Edna Nadine Turnbull, 91, and Robert Sharpe, 69 — and destroyed more than 1,000 homes and commercial structures in Louisville, Superior and unincorporated Boulder County.

By the numbers: The blaze cost more than $2 billion in damage and burned more than 6,000 acres.

  • While Colorado is accustomed to wildfires, the blaze tore through dense neighborhoods. The fire was made worse by hot, dry conditions and long stretches of warm weather — a likely byproduct of climate change.

Between the lines: Johnson said restrictions were in place when it happened and said high winds contributed to the wildfire's spreading.

  • He also confirmed the people who lived at the site where the first fire started were members of the Twelve Tribes, a religious group. The group had been a focus of investigation for their alleged role in the flames, the Denver Post reported last year.
  • But: Firefighters had OK'd their burying of scrapwood days before the fire started.

The intrigue: District Attorney Michael Dougherty said after reviewing evidence, no criminal charges will be filed in connection to the blaze.

Editor's note: This story has been updated to include information about the Twelve Tribes alleged role in the fire and a statement from Xcel Energy.

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