SOUTH LAKE TAHOE, Calif. -- No one could claim surprise last week when tall flames raged across more than 3,000 acres and consumed 254 homes.
The ingredients for a devastating wildfire have long been in place in the Tahoe basin, where 32,000 houses are tucked into an overgrown forest of pine and fir. Three million visitors a year come to relax on the shores of one of the deepest and clearest lakes in the world.
Investigators said the blaze was started by an illegal campfire. It was mostly contained, and some firefighters were beginning to withdraw, they said.
A U.S. Forest Service investigation found that the fire south of Lake Tahoe was built in a campfire-restricted area but said there was no evidence that it was set to spark the fire, which has displaced about 3,500 people.
Heavy logging in the 1800s, followed by dense regrowth and a century of fire suppression thwarted the basin's natural wildfire cycle and helped turn the basin into a tinderbox.
Efforts to reduce the fire hazard, under way for more than a decade, were slowed by an early shortage of funding and some public resistance to extensive tree cutting.
The fire itself taught emergency planners a grim lesson. Even text-book precautions can go up in flames, if the fire is hot enough and the winds are strong.
"This fire was the absolute worst-case nightmare we feared," said Julie Regan, communications and legislative affairs chief for the Tahoe Regional Planning Agency, a bi-state agency that became a magnet for blame last week as irate residents insisted that the organization's strict environmental regulations had interfered with forest thinning.
While some local officials say the agency's erosion control requirements have made it harder to get thinning approval, agency rules did not stop thinning on public lands bordering the burned subdivision.
The U.S. Forest Service, which manages most of the land in the basin, had thinned some 3,000 acres in and around the burned area during the past eight years, including a just-completed project.
"In this particular situation, probably not a whole lot of anything would have stopped this fire from devastating the small subdivision it burned," said Dave Marlow, the vegetation, fire and fuels manager for the Forest Service's Lake Tahoe Basin Management Unit.
The thinning, which removes dense brush and tree growth, slowed the flames but could not halt them as they were driven into tree tops by dry, strong winds.
The thinning projects, Marlow said, "are designed for average weather and fire conditions, and when this fire broke out, we had extreme fire weather." Still, he added, the thinning work "really helped in terms of keeping losses down. It could have been worse."
The fire broke out June 24 in 30-mile-an-hour gusts at the south end of the lake after two days of 5 percent humidity.
About 21,000 acres of federal, private and state land have been thinned in the basin in the past decade, Regan said. But 67,000 more acres need treatment.
The funding prospects have improved as a result of 2003 congressional legislation that funnels money to the basin. The Forest Service got $10 million last year and will receive the same sum this year for thinning projects. It plans to speed up the pace of fuels reduction work to 4,200 acres a year for the next decade.
Bettina Boxall and Julie Cart write for the Los Angeles Times. The Associated Press contributed to this report.