Fire overnight destroys part of Longmont’s historic Sugar Mill factory
Due to hazardous materials inside a 2-story building, firefighters monitored the fire overnight at the 120-year-old site


Crews will continue to monitor a fire Tuesday morning that fully engulfed a two-story building on the old Sugar Mill Factory near Longmont, the Boulder County Sheriff’s Office said.
Firefighters from the Mountain View Fire Rescue and Longmont Fire Department responded to the fire just after midnight but due to hazardous materials and conditions, they could not fight the fire, the sheriff’s office said.
Early Tuesday morning, around 6:45 a.m., crews were seen putting water on the flames, according to local news reports.
The cause of the fire is under investigation.
Sheriff’s deputies will stay on the property, along with firefighters, Tuesday. While there is no danger to the public, officials are urging people to stay away from the area.
The property is no stranger to fire — it has seen three fires since 2016. The last fire, in August, was concentrated around wood materials stored in a machine shed.
The other fires sparked in December 2020, December 2017 and September 2016.
In 2012, Boulder County Public Heath issued a warning to stay away from the buildings due to asbestos, unstable structures and other dangerous structures by putting up a “stay out” sign at the property, according to a 2020 report commissioned by the city. Large fires had been started by trespassers, which increased the instability of the buildings, the report said.
The property, first built in 1905, has been abandoned since 1977 and shut off to the public, though the Great Western Sugar Company still uses the silos for sugar storage.
This is a developing story that will be updated.