FRESNO, Calif. (AP) - A giant wildfire raging out of control grew to nearly 200 square miles Friday and spread into Yosemite National Park at the height of the summer season for one of California's most popular tourist destinations.
While it has closed some backcountry hiking, it was not threatening the Yosemite Valley, home to such iconic sights as the Half Dome and El Capitan rock formations and Bridalveil and Yosemite falls.
But in an unusual move, Gov. Jerry Brown declared a state of emergency for San Francisco 150 miles away because of the threat to the city's utilities.
The blaze had already done some damage and threatened more to the lines and stations that pipe power to San Francisco, so Brown, who had declared an emergency for the fire area earlier in the week, made the unusual move of extending it to the city across the state.
San Francisco gets 85 percent of its water from the Yosemite-area Hetch Hetchy reservoir that is about 4 miles from the fire, though that had yet to be affected. But it was forced to shut down two of its three hydroelectric power stations in the area.
The city has so far been able to buy power on the open market and use existing supplies, but further disruptions or damage could have an effect, according to city power officials and the governor's statement.
The declaration frees funding and resources to help the city and makes it eligible for more federal funds to help with power shortages and outages or water problems.
The weeklong blaze on the timbered slopes of the Western Sierra Nevada has spread to 196 square miles and was only 5 percent contained. It continued to grow in several directions, although "most of the fire activity is pushing to the east right into Yosemite," said Daniel Berlant, spokesman for the California Department of Forestry and Fire Protection.
Smoke blowing across the Sierra into the state of Nevada forced officials in several counties to cancel outdoor school activities and issue health advisories, especially for people with respiratory problems.
Authorities urged more evacuations in nearby communities where thousands have already been forced out by flames.
The fire was threatening about 5,500 residences, according to the U.S. Forest Service. The blaze has destroyed four homes and 12 outbuildings in several different areas. More than 2,000 firefighters were on the lines and one sustained a heat-related injury.
While the park remained open, the blaze closed a 4-mile stretch of State Route 120, one of three entrances into Yosemite on the west side. Two other western routes and an eastern route were open.
Within the park, the blaze was burning on about 17 square miles in a remote area around Lake Eleanor, Yosemite spokeswoman Kari Cobb said.
Backcountry permits are required to hike in that area, Cobb said. The park was no longer issuing those and had contacted every person who had received a permit to go there. Two roads into that area were closed and occupants of a campground near the Route 120 west entrance were relocated.
"We don't have anybody we know of in that area based on the permits we have out now," she said.
The fire was more than 20 miles from Yosemite Valley and skies there were "crystal clear," Cobb said.
"Right now there are no closures, and no visitor services are being affected in the park," he said. "We just have to take one day at a time depending on fire activity."
On Friday, officials issued voluntary evacuation advisories for two new towns _ Tuolumne City, population 1,800, and Ponderosa Hills, a community of several hundred _ which are about five miles from the fire line, Forest Service spokesman Jerry Snyder said.
A mandatory evacuation order remained in effect for part of Pine Mountain Lake, a summer gated community a few miles from the fire.
"It feels a little bit like a war zone, with helicopters flying overhead, bombers dropping retardant and 10 engine companies stationed on our street," said Ken Codeglia, a retired Pine Mountain Lake resident who decided to stay to protect his house with his own hoses and fire retardant system. "But if the fire gets very hot and firefighters evacuate, I will run with them."
Officials previously advised voluntary evacuations of more than a thousand other homes, several organized camps and at least two campgrounds in the area outside the park's boundary.
More homes, businesses and hotels are threatened in nearby Groveland, a community of 600 about 5 miles from the fire and 25 miles from the entrance of Yosemite.
Usually filled with tourists, the streets are now swarming with firefighters, evacuees, and news crews, said Doug Edwards, owner of Hotel Charlotte on Main Street.
"We usually book out six months solid with no vacancies and turn away 30-40 people a night. That's all changed," Edwards said. "All we're getting for the next three weeks is cancellations. It's a huge impact on the community in terms of revenue dollars."
Park fire crews are working to clear brush and other fire fuels from the Merced and Tuolumne Groves of Giant Sequoias as a precaution.
The fire is raging in the same region where a 1987 fire killed a firefighter, burned hundreds of thousands of acres, and forced several thousand people out of their homes.
Associated Press writers Jason Dearen, Lisa Leff and Andrew Dalton in San Francisco also contributed to this report.
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