Yosemite National Park Fire Threatens Water, Electrical Supply for SF Bay Area

Aug 26, 2013 08:52 AM EDT

The Yosemite wildfire in California, known as Rim Fire, has burned over 234 square miles of land or 149,780 acres in the Sierra Nevada, threatening the shutdown of the main source of electrical and water supply for the 2.6 million people in San Francisco Bay Area.

The Rim fire that started out on Aug. 17 has been contained only about 15 percent. Nearly 3,700 firefighters are deployed and millions of dollars have been spent in the firefighting costs. So far, the cause of the fire has not been determined, but remains under investigation, which may would take months, if not weeks, to reach a conclusion.

California Gov. Jerry Brown has declared a state of emergency for San Francisco as the flames have come within a couple miles of the Hetch Hetchy Reservoir. So far, the debris and ash from the fire has fallen on the reservoir, but hasn’t sunk far enough to reach the intake pumps. Should sensors in SF’s water system detect a significant rise in turbidity, the reservoir would be closed off, and the water utility would switch to other supplies near the Bay area, which authorities said would last for six months, according to the Weather Channel.

Two of the three powerhouses that provide electricity for San Francisco were damaged by the fire and have been taken offline. To make up for the power loss, SF is purchasing electricity from other utilities via the regional electrical grid, the NBC News reports.

Meanwhile, utility officials used a new $4.6 billion gravity-operated pipeline system to move water quickly to reservoirs closer to San Francisco.

“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, according to the Weather Channel. “We’re bringing down as much water as possible and replenishing all of the local reservoirs.”

Park officials cleared brush and set sprinklers on two groves of giant sequoias that were seven to 10 miles away from the fire’s front lines, park spokesman told the Weather Channel. While sequoias have a chemical in their bark to help them resist fire, they can be damaged when flames move through slowly.

The U.S. Forest Service said the fire was threatening about 4,500 structures and destroyed at least 23. The rugged terrain, strong winds and dry conditions have hampered firefighters’ efforts to contain the wildfire.