California,USA: — A ForestService report says that homes were set ablaze by embers from other buildingsand that a number of factors caused the fire’s spread.
It wasn’t flaming trees that ignited many of the 254 homes lost in the LakeTahoe wildfire in June, it was other burning houses, according to a federalreport released Friday.
The analysis of the 3,072-acre Angora blaze found no single factor responsiblefor the fire’s spread into residential neighborhoods near South Lake Tahoe.
The review instead suggested that a number of elements were at play, includingunusually dry wind gusts, houses that had been built with flammable materialsand long-ago commercial logging projects that had left dead treetops and limbson the ground.
But the U.S. Forest Service report examined the effect of thinning projectsconducted within and adjacent to the burn area to reduce fire risk and concludedthat they had worked.
Efforts to reduce fuels were “very effective in most cases,” saidKathy Murphy, regional fuels operations manager for the Forest Service and oneof the report’s authors. “They’re not designed to stop a fire. They’redesigned to lower the intensity of a fire.”
The 32-page report includes several photographs of houses engulfed in flames andsurrounded by trees that did not burn. A large number of homes were set ablazeby embers blown from other buildings rather than by the burning forest, thereport’s authors concluded.
In some cases it appeared the houses caught fire from low-growing vegetationthat had not been cleared. In other instances, embers ignited decks or shakeroofs or piles of firewood stacked near the homes.
On some lots, char marks showed that the houses set the trees on fire.
The Angora blaze the biggest recorded wildland fire in the Lake TahoeBasin’s history was caused by an untended campfire the afternoon of June 24.Driven by dry winds that gusted up to 40 mph, firefighters said, the flames didmost of their damage on the first day.
Chris Sauer, the fire chief for the community of Fallen Leaf Lake, near wherethe blaze began, said in June that firefighters had about 30 engines mobilizedduring the initial two hours, all trying to protect about 300 homes. “Youdo the math. I was amazed about how fast some of these structures burned to theground,” he said.
Steve Ryberg, one of the incident commanders for the Forest Service, told TheTimes that the presence of so many houses made the firefighting more difficult.
“You couldn’t fight the fire as much as you were trying to get people outof the way and try to protect the structures that were in the way,” he said.
The wildfire raced through acreage that had been commercially thinned in themid-1990s to remove insect-killed trees. The Forest Service had allowed theloggers to leave logging debris scattered on the ground and the long-deadmaterial provided fuel for the flames.
The report concluded that the fire burned just as intensely in those areas as onforest acreage that had not been thinned.
Rex Norman, spokesman for the Forest Service in the Lake Tahoe Basin, said thecommercial projects “would not be done today under those types ofobjectives because we quite frankly have learned a great deal” since then.
“By 2000, we were introducing a lot more modern fuels treatments,” hesaid.