"We just got so much rain within a short period of time -- about eight inches of rain," said Stinson Beach Fire Chief Kenny Stevens.
RELATED: Stinson Beach parking lot badly damaged by flooding
And then a waterfall was left behind from where the parking lot collapsed, close to where it meets Stinson Beach.
Forty parking spaces were washed out to sea.
"This is crazy, I'm always boogie boarding. I've never seen anything like this," said Stinson Beach resident Ocean Nage. "This much water, that's all out unbelievable."
"Huge huge water, never seen it like this," said Fairfax resident Ali Vogt. "Didn't think could get to the beach -- but found a way."
Official word from the Golden Gate National Park Service is that both Stinson Beach and Muir Woods are closed to the public because of the storm damage.
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"We were going to have an adventure and we decided to have it no matter what," said San Rafael resident Kim Iglinski.
At nearby Parkside, the damage is adding up. The market and snack bar are closed because of it, but the cafe is still open.
The last time water rushed in like this, was 36 years ago.
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