California Rim Fire image courtesy of the USDA.

California governor Jerry Brown declared a state of emergency for San Francisco County when a large wildfire on the western slopes of the Sierra Nevada mountains threatened to disrupt public utilities. Two of the three hydroelectric power stations in the region were forced to shut down. San Francisco also gets 85% of its water from the nearby Hetch Hetchy reservoir. Most of the western US is in drought and the recent increase in the number …