Marshall fire was caused by reignited burn on residential property, Xcel Energy power line, Boulder County authorities say 

No evidence of a crime as details on the origin and cause of the Marshall fire were shared Thursday, capping an 18-month probe into December 2021 wildfire that killed two people, destroyed more than 1,000 homes and businesses

The Marshall fire burns in Boulder County on Dec. 30, 2021.
Jeremy Sparig, Special to The Colorado Sun

BOULDER — Six-day-old buried embers from a previous brush-pile fire on a residential property reignited and together with sparks from an “unmoored” Xcel Energy power line started the Marshall fire on Dec. 30 in Boulder County, the sheriff said Thursday morning.

A residential fire on Dec. 24 to burn scrap wood and tree branches resurfaced because of the winds on Dec. 30, said Boulder County Sheriff Curtis Johnson. The sheriff said the fire was put out “responsibly” on Dec. 24 when it was buried. But around 11 a.m. Dec. 30 high winds, pushing 100 mph, resurfaced and started a shed on fire on Eldorado Springs Road.

He said that second fire was started that day by Xcel power lines and also quickly spread. He said the underground coal fires cannot be ruled out.

The district attorney’s office determined there was ” insufficient or no evidence of a crime” and no reason to file charges, said Boulder County District Attorney Michael Dougherty.

The announcement comes nearly 18 months after the fire exploded in late December 2021 and raced across 6,000 acres, as gale-force winds pushed embers across parched grassland into subdivisions bordering open space. Two people died in the fire and more than 1,000 homes and businesses were destroyed in Louisville, Superior and unincorporated Boulder County. 

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