"When you see 0%, that doesn't mean there's no capacity, no one's allowed into an ICU. It means we're now in our surge phase, which is about 20% additional capacity that we can make available," Newsom said.
Four alternative care sites have already been set up to help handle overflow patients. The sites are located at Imperial Valley College, Sleep Train Arena in Sacramento, Porterville Developmental Center in Tulare County and Fairview Developmental Center in Orange County.
Some sites are accepting COVID-positive patients while others are just helping decompress local hospitals, Newsom said.
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There are more sites strategically placed around the state on "warm status," the governor said, ready to open and accept patients as needed.
"I don't want people to be alarmed by that, except I do want to raise the alarm bell," the governor said.
As of Friday, 98% of the state's population was under a stay-at-home order due to increasingly critical intensive care capacity. Every region except far Northern California is under a modified lockdown.
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The situation is the worst in the San Joaquin Valley and Southern California, where the remaining ICU capacity was reported at 0% Friday. Both are in a "surge phase" of hospitalizations, the governor said.