Yosemite Valley reopens after big storm, flooding

After an intense tropical storm caused flooding in roads and rivers throughout Yosemite Valley on Saturday, the national park reopened to vehicles and visitors on Sunday afternoon.

Park crews were working to clear water, rocks and debris from roads early Sunday morning, and officials warned of delays along several routes. Park services, restaurants and lodging have mostly reopened.

The storm Saturday brought less water than expected, dumping 2.5 inches of rain instead of the forecast 4 inches. But it was enough to swell the Merced River to as high as 13.73 feet, 4 feet over what’s considered a flood. Roads and campsites on Saturday were under as much as 4 feet of water, but the water had mostly receded by early Sunday morning, according to park officials.

The storm that hit the area on Friday and Saturday was part of a larger weather system that established rainfall records in Sacramento, Oroville and San Francisco and brought more than 6 inches of rain to parts of the Bay Area. The storm was an example of an “atmospheric river,” a long plume of water vapor loaded with warm tropical moisture.

Officials with the California Department of Water Resources have closely monitored the storm’s effects on Lake Oroville, where a partially repaired spillway may be used for the first time since it crumbled last year and prompted evacuations downstream.

Officials have tried to keep the lake’s levels low, but a series of storms hit in late March.

Water Resources officials said they would open the spillway gates to release water if the lake rises to 830 feet. On Sunday morning, censors showed the reservoir waters at 799.5 feet. At 901 feet, the lake would spill over.