Two firefighters watch trees burn while battling the Rim Fire near Yosemite National Park, Calif., Aug. 26, 2013.
CREDIT: Jae C. Hong/AP
YOSEMITE VILLAGE, Calif. (USATODAY.com) - Though a massive fire rages a few miles away, all is peaceful in bucolic Yosemite Village, where park rangers remain optimistic about the coming holiday weekend's tourism assault.
"We are minimally impacted here, with all visitors services and campgrounds open to the public," says Kari Cobb, park ranger and spokesperson for Yosemite National Park.
"Visitors who are planning to come shouldn't cancel their (Labor Day) weekend plans. They may have to modify them, if they were planning to go to Hetch Hetchy (reservoir) or if they were planning to take Highway 120,'' she adds, noting that both recently closed due to the encroaching Rim Fire that has burned more than 250 square miles.
Cobb says "less than 3% of Yosemite National Park is impacted by this fire, adding that in the past 24 hours the fire has been "moving northeast and is largely in wilderness areas with no lodging."
"It's 20 miles away from the valley floor," she says. "The winds are pushing the smoke (north) toward Lake Tahoe."
Thousands of firefighters working on the ground and from the air made progress Monday battling the massive, stubborn wildfire that was still growing on the western edge of the park and prompted San Francisco officials to take steps to protect the city's water supply.
The fire has burned an area estimated at more than 251 square miles, state fire officials said Monday evening. They said they had established 20% containment, up from 15% when the day began.
At least 23 structures have been destroyed and 4,500 are threatened, according to the California Department of Forestry and Fire Protection. More than 3,750 firefighters were battling the blaze, aided by 15 helicopters and 460 fire engines.
Almost all park areas are open, said Scott Gediman, a park ranger.
"We've got clear blue skies here in Yosemite Valley," he said. "The park is busy. I was just out walking around, and there are plenty of people here."
In San Francisco, utility officials monitored the Hetch Hetchy reservoir, inside the park, for clarity and used a gravity-operated pipeline system to move water to reservoirs closer to San Francisco. The Hetch Hetchy supplies water to 2.6 million people in the Bay area, 150 miles to the west.
"We're taking advantage that the water we're receiving is still of good quality," said Harlan Kelly Jr., general manager of the city's Public Utilities Commission. "We're bringing down as much water as possible and replenishing all of the local reservoirs."
At the same time, utility officials gave assurances that they have a six-month supply of water in reservoirs near the Bay area.
Fire officials said the fire has "extreme" growth potential and is in extremely rugged terrain.
Smoke continues to be an issue, and visibility within the fire's perimeter is less than a mile, according to InciWeb, the federal fire information site. The blaze has burned 23 structures. Mandatory evacuations were ordered for residents in some areas in the path of the fire while other towns, including Tuolumne and Mi-Wuk Village, were under advisory evacuations.
Larry Brown lives in Sonora, Calif., more than 10 miles from the fire. "It's about a half-mile visibility here because of the smoke. Everything smells like smoke. When I open the car door, it smells inside," he said.
Brown is a ham radio operator with the Tuolumne County Amateur Radio Electronics Society which is manning phone lines at the Sonora community information line for those affected by the fire.
He and others have been impressed "as always," he says, with the work of the firefighters. He says people who live in the Sierra realize that fire is a natural part of the landscape.
"This is part of the ecosystem," he says. "We do burn in here every so often. There are plants and things within the canyons that are reliant on the fire to open their seeds, that have adapted to that environment."
Despite the steps taken as a precaution to move water closer to the city, San Francisco's water supply is safe, said Charles Sheehan, a spokesman for the San Francisco Public Utilities Commission.
The reservoir supplies water to 2.6 million people in the San Francisco Bay area, sending approximately 260 million gallons of waterevery day.
"There's no change to water quality," Sheehan said. "We have instruments monitoring the water constantly." The turbidity, a measure of particles in the water, is 0.2, which is normal, he said. If the turbidity were to reach 5.0, the utility would switch to suppliers of water from other nearby reservoirs that it has emergency contracts with.
Also a concern is the power generated by the reservoir's dam, used for some municipal buildings in the city, including San Francisco International Airport and San Francisco General Hospital.
The system has three powerhouses, two of which were taken offline Saturday because of fire damage, Sheehan said. Twelve to 14 miles of power transmission line were also taken out of operation. "There's been some damage, we don't know how much," Sheehan said.
Even if the powerhouses were all shut down, there would be no loss of power in San Francisco. The city's electrical infrastructure is linked to the main electrical grid, and it would simply purchase power to supplement the lost transmissions. Since the fire began Aug. 19, the city has purchased about $600,000 in supplemental power, the Public Utilities Commission website said.
California Gov. Jerry Brown has declared a state of emergency for San Francisco because of the possible threat to the city's water and electrical infrastructure.
A 91-year-old family camp owned by the city of Berkeley near the town of Groveland, Calif. was destroyed over the weekend, said Mathai Chakko, a Berkeley spokesman.
Berkeley Tuolumne family camp was founded in 1922. Each year, about 1,000 families spend a week at the city-owned camp. "We had 4,364 people in the camp this summer," Chakko said.
Berkeley doesn't know how bad things are at the camp. "The damage is pretty extensive, but it's still not safe enough to send someone in there to assess," Chakko said.
Weise reported from San Francisco.
Contributing: Associated Press