From the San Francisco Chronicle:
“The giant wildfire burning in and around Yosemite National Park struck the shores of the Hetch Hetchy Reservoir Tuesday, threatening the famously pure mountain water that feeds the taps of 2.6 million Bay Area residents.
“San Francisco water managers, who operate the reservoir, reported that water quality had not been compromised. Fears that falling ash could pollute the supply have been addressed - at least for now – by diverting unsullied water from the 8-mile-long Hetch Hetchy to smaller back-up reservoirs in the Bay Area, should it be needed. …
“But wildfire experts say problems for San Francisco’s water agency may come later.”