The late-season Marshall Fire in Boulder County, Colorado, which destroyed almost 1,000 structures after strong winds accelerated the spread, is estimated to have resulted in insured losses of approximately $1 billion, according to risk modeller Karen Clark & Company.
On December 30th, 2021, a rare and devastating wildfire started in Boulder County.
Although the fire only burned through an area of some 6,000 acres over two days, as around 10 inches of snow contained the fire, it’s still likely to become the costliest fire in the state’s history.
Alongside the destruction of nearly 1,000 structures, a further 100+ structures were damaged as a prolonged period of unusually warm and dry weather along the Colorado Front Range primed the environment for such an event.
As KCC reports, entire subdivisions throughout Superior, Louisville, and Boulder County were devastated by the wildfire.
In Louisville, 553 structures were destroyed and 45 damaged. Superior saw the destruction of 332 structures while 60 were damaged. And in Boulder County, 106 structures were destroyed and 22 damaged.
As the figures show, most of the damage occurred in Louisville where hundreds of homes and a large commercial area were among the destroyed structures.
“While the exact cause of the Marshall Fire is still under investigation, an intense, downslope wind event that impacted the Colorado Front Range assisted with the fast rate of spread. On the morning of December 30, strong winds were flowing nearly due east across the high peaks of the Colorado Rockies in the mid-levels of the atmosphere.
“By midday, an amplified mountain wave had developed over the Front Range and began to bring those strong mid-level winds to the surface, where gusts of over 100 mph began to be reported,” says KCC.
At an estimated cost of $1 billion, the industry loss should mostly be assumed by the primary insurance market, with little impact to reinsurers.
However, it is the most destructive wildfire in Colorado history. In October 2020, the East Troublesome Fire destroyed more than 500 structures and cost the insurance industry almost $500 million, making it roughly half as destructive as the December 2021 Marshall Fire.