According to reports, the Yosemite Fire has grown to a point where it’s estimated to be three-times the size of San Francisco, which places it at about 147 square miles in size.
In fact, it’s growing so fast, the Yosemite Fire is threatening the very source of power and water for the City and County of San Francisco. San Francisco gets an estimated 85 percent of its water from the Hetch Hetchy reservoir in the Yosemite-area and that is about 4 miles from where the fire is right now. California Governor Jerry Brown has declared a state-of-emergency.
The Yosemite Fire has drawn the work of more than 1,800 firefighters, who have been battling the flames on the ground and by aircraft.
The Yosemite Fire: How Did It Start?
While there’s no definitive report as of this writing, the Yosemite Fire appears to have started on August 17th, and was called “The Rim Fire” at Groveland, Tuolumne County in California according to Twitter accounts at the time.
The Incident Information Report website has this summary of how Yosemite Fire has spread:
The Rim fire has transitioned to the Southern Area IMT1 Blue Team and remains in unified command with Cal Fire.
The fire continues to increase in size and actively through the day and night. It continues to exhibit very large fire growth due to extremely dry fuels and inaccessible terrain. Aerial resources are being effective with MAFFS and VLAT DC-10 air tankers prepping locations in advance of the fires spread towards the Highway 108 corridor.
The availability of fixed wing air craft is pertinent to the success of suppression operations. The use of Maffs C-130s and the V-LAT DC-10 has greatly improved suppression efforts. Use of Military Rotary wing aircraft continues today.
Due to inaccessible, steep terrain and active fire behavior a combination of direct and indirect attack will be used on this incident. Direct line suppression efforts are impeded by difficult access and steep inaccessible terrain. Active fire behavior today raises safety concerns for crews adjacent to the fire’s edge. Smoke exposure within the deep drainage of the Clavey River will be an issue for fire crews as well.