Prescribed fires used effectively, with few escapes, in Colorado
By Bob Berwyn
“The firefighters were surprised at material reigniting in the black and wondered “how is this stuff burning.”
SUMMIT COUNTY — Upgrading weather forecasting data and boosting standards for post-prescribed fire mop-up operations could help prevent future prescribed burns from escaping, according to a review team that today finalized a report on the circumstances that led to the deadly and destructive Lower North Fork Fire in Jefferson County, Colorado.
The Lower North Fork Fire started March 26 after winds of up to 55 mph blew embers from a Colorado State Forest Service prescribed fire on Denver Water land across a 200-foot buffer zone into unburned fuels. The fire killed three people and damaged or destroyed 25 homes.
The Colorado State Forest Service conducted 175 prescribed fires on 14,189 acres between 2004 and 2011, with only two fires escaping. A review of other prescribed fires that burned beyond the planned boundaries showed that unexpectedly strong and long-lasting winds were a significant factor in about half the escapes.
The report concluded that the 200-foot buffer was not adequate to contain the prescribed fire given the windy weather and dryness of the nearby fuels. The report also suggested that fire managers may have underestimated the dryness of fuels in the region and recommended replacing an existing drought index with more up-to-date tools to assess how fire hazards might change over time. (more…)