Cal Fire trucks move at dawn through Groveland, where a banner thanks firefighters… (Don Bartletti, Los Angeles…)
GROVELAND, Calif. — The Rim fire should be fully contained by Sept. 10, a fire official said Wednesday, as lower temperatures, higher humidity and lighter winds allow crews to make headway against the sprawling blaze that has swept into Yosemite National Park.
"That's given us a greater opportunity to get in there and strengthen our containment lines," said Daniel Berlant, spokesman of the California Department of Forestry and Fire Protection.
Officials have said they expect it to burn until snow begins to fall.
Firefighters have battled the stubborn blaze for nearly two weeks and have it 30% contained. The effort has cost at least $39.2 million and required some 4,500 firefighters. More than 192,500 acres — about 301 square miles — have burned, causing three injuries and destroying 111 structures, including 11 homes.
But the rate the fire is spreading has slowed in the last two days. Last week, the fire burned 50,000 acres in one 24-hour span and 30,000 acres in another, Berlant said. But in the last two days, the rate of spread has slowed to 10,000 acres one day and 5,000 on another.
On Wednesday morning, officials employed an unmanned drone aircraft for the first time against the Rim fire.
A remotely piloted MQ-1 plane belonging to the California Air National Guard began flying a 20-hour mission Wednesday morning, alerting crews to a spot fire and providing a more comprehensive fire map.
The drone, about the size of a small Cessna, takes off from the Victorville airport and is operated from March Air Reserve Base in Riverside County, said Lt. Col. Tom Keegan of the National Guard.
Unmanned aircraft have been used sparingly on fires but are gaining favor as a cheaper, more efficient tool for fire bosses to better understand where fires are going and how they are behaving.
They are especially prized for the ability to beam real-time pictures directly to commanders, who can make tactical adjustments more quickly. The aircraft are equipped with infrared heat sensors and a swiveling camera operated by a remote pilot.
Unlike piloted aircraft deployed against fires, drones can fly at night and in high winds and smoke. They fly at about 18,000 feet and cost about $800 an hour to operate, Keegan said.
Gov. Jerry Brown passed along a request for the drone from incident commander Mike Wilkins to the secretary of Defense. The Federal Aviation Administration must also approve use of the MQ-1, which is escorted to the fire by a lead plane.
According to Kelly Huston, the deputy director of the governor's Office of Emergency Services, drones were used experimentally on fires in 2003 and in more extensively in 2007.
"The incident commander wanted better data and better mapping of this fire," Huston said.
Huston said the governor was monitoring the escalating costs associated with the fire, including the damage to infrastructure and utilities, and will consider whether to request a national emergency declaration from the Federal Emergency Management Agency.
On the ground, firefighters reached a river on the fire's northwest edge above the Hetch Hetchy Reservoir and set up a launching point to extinguish advancing flames. Crews south of the fire launched a controlled burn to keep it from advancing up California 120, said Dick Fleishman of the U.S. Forest Service.
"I think we've got a really good anchor on this thing," Fleishman said. "The plan of attack is to just keep going on the containment lines and march on the northwest side and keep flanking on the bottom side and get around it."
With the winds pushing from the southwest, the blaze has followed the Stanislaus National Forest ridgelines deeper into dense, bone-dry brush and trees. Eventually that path will lead to a granite face and stop the fire in its path, officials said.
A plan to launch a controlled burn south of the Hetch Hetchy Reservoir was scrapped because conditions weren't right, Fleishman said.
"Any time you add fire to fire, you have got to be really careful," he said. "The advantage is we're fighting fire under our terms instead of it pushing and us chasing it all the time."
Cart reported from Groveland, Lopez and Serna from Los Angeles.