This archived news story is available only for your personal, non-commercial use. Information in the story may be outdated or superseded by additional information. Reading or replaying the story in its archived form does not constitute a republication of the story.
SALT LAKE CITY — Fire crews have begun wrapping up battling Utah’s largest remaining wildfires in the past couple of days.
The massive Dollar Ridge Fire that blackened more than 107 square miles of land in Duchesne and Wasatch counties, burning 74 homes and hundreds of other structures. A section of the fire flared up again in early August, but no new structures were burned.
The Coal Hollow Fire in southeast Utah County was also 80 percent contained as of Saturday morning, according to the National Wildfire Coordinating Group. That fire scorched more than 46 square miles around Spanish Fork Canyon since Aug. 4.
While the focus is to extinguish fires once they begin, there are also investigators on scene to figure out how they begin.
You may have seen or heard the statistic that as many 90 percent of wildfires are human-caused, according to the National Park Service. A 2017 study published in the Proceedings of the National Academy of Sciences found that 84 percent of wildfires in the U.S from 1992 to 2012 were human-caused.
How about Utah’s wildfires this season? The numbers are less dramatic, but still staggering.
Jason Curry, spokesman for the Utah Division of Forestry, Fire and State Lands, said that as of Aug. 15, a little more than half of Utah’s some 1,000 fires were human-caused. An exact cause was found in only two-thirds of the total amount of fires. The other third includes the Dollar Ridge Fire, where officials have said they may never know how it truly started.
However, the leading known cause of fires is “equipment,” which accounted for 35 percent of the 363 fires with a known cause, as of Aug. 15. This includes everything from flat tires and electrical malfunctions to farm equipment, landscaping equipment, dragging metal, ATV misuse, chainsaws and any other type of machinery humans use.
Twenty-four percent of the fires came from debris burning, such as tree limbs. Campfires accounted for another 11 percent, while powerlines and fireworks (each 7 percent) rounded out the top five causes.
Structure fires (4 percent), welding/grinding (3 percent), firearms (3 percent), railroads (2.5 percent), children (2 percent), arson (0.8 percent) and smoking (0.6 percent) have also factored in fires this year.
The cause of the fires listed as unknown was either never investigated or a conclusive cause was never determined.
Lightning, which caused the Coal Hollow Fire, has been the primary natural cause of Utah’s wildfires.