SACRAMENTO, Calif. — Scientists are assessing the damage from a massive wildfire burning across Yosemite National Park, laying plans to protect habitat and waterways as the fall rainy season approaches.
Members of the federal Burned Area Emergency Response team hiked the rugged Sierra Nevada terrain Saturday even as thousands of firefighters still were battling the four-week-old blaze, now the third-largest wildfire in modern California history.
Federal officials have amassed a team of 50 scientists, more than twice the number usually deployed to assess wildfire damage. With so many people assigned to the job, they hope to have a preliminary report ready in two weeks so remediation can start before the first storms, said Alex Janicki, the Stanislaus National Forest BAER response coordinator.
Team members work to identify areas at the highest risk for erosion into streams, the Tuolumne River, and the Hetch Hetchy Reservoir, San Francisco’s famously pure water supply.
The wildfire started in the Stanislaus National Forest Aug. 17 when a hunter’s illegal fire swept out of control, and it has burned 394 square miles.
It has cost more than $89 million to fight, and officials said it will cost tens of millions of dollars more to repair the environmental damage alone.
About 5 square miles of the burned area is in the watershed of a reservoir serving 2.8 million people — the only one in a national park.
‘‘That’s 5 square miles of watershed with very steep slopes,’’ Janicki said ‘‘We are going to need some engineering to protect them.’’
So far the water remains clear despite falling ash, and the city water utility has a six month supply in reservoirs closer to the Bay Area.
The BAER team will consist of hydrologists, botanists, archeologists, biologists, geologists and soil scientists from the US Forest Service, Yosemite National Park, the Natural Resource Conservation, and the US Geological Survey.