The biggest surf was expected at south-facing beaches in Los Angeles and Ventura counties, with wave sets topping 15 feet in some areas, according to the National Weather Service. A high surf advisory was in effect through Friday before calmer waters return.
The weather service called this week's storm surge the most significant southerly swell event since July 25, 1996.
Spectators lined the shore of the Wedge in Newport Beach on Wednesday, where 20-foot waves were crashing and some of the world's best surfers were riding.
"It's as big as Southern California ever gets," Peter Mel, a prominent big-wave surfer just back from an event in Tahiti, told the Orange County Register. "It's perfect."
Amateurs took to the water too, at least the experienced ones who wary lifeguards would allow in.
Among them was Joshua Magner, 35, who has been surfing since he was 10, and said being in the water was life-altering.
"It's like being born," he said as he zipped his wetsuit and prepared to go back out. "You don't know what the outcome will be, but when you do make it through all that pressure is alleviated, it's liberation, truly the feeling of liberation."
Asked if he was afraid, he replied, "I was scared leaving my house. Dude, I was scared last night. I couldn't sleep."
Some gawkers had to park nearly 2 miles away and walk to the scene. One man rode a skateboard, carrying a baby. A man put a sign on his car offering his parking space for cash and another was selling commemorative T-shirts for $20 apiece.
Lifeguards up and down the coast sought to keep anyone out of the water who did not have strong experience and were kept busy making rescues all day.
Residents of about four blocks of homes along Seal Beach, south of Los Angeles, swept seawater from ground-floor rooms, and bulldozers reinforced a 6-foot-tall sand berm hastily built to protect shoreline structures.
The berm — a measure normally not needed until winter storms — and the use of pumps prevented more water intrusion during the Wednesday morning high tide.
The towering waves and rip currents were being produced by swells generated by Hurricane Marie in the Pacific Ocean about 800 miles west of the southern tip of Mexico's Baja California peninsula. While Hurricane-generated waves reached California's shores, the storm itself would remain far from the state.
Marie weakened to tropical storm levels, but life-threatening water conditions were expected to continue through Thursday.
West of Malibu, the old Cove House, used by lifeguards as a home base for decades, collapsed in big waves late Wednesday, several hours after it was emptied out.
"A lot of lifeguards have put a lot of time into it over the years. It's sad," retired lifeguard Norm Chapman told KCBS-TV. "It's hard not to get choked up."
Two cargo terminals at the Port of Long Beach stopped operations late Tuesday because surging, 10- to 15-foot-high waves endangered dockworkers.
The powerful surge also tossed heavy rocks from a seawall onto a road, causing damage and closing the roadway.
On Santa Catalina Island south of Los Angeles, a heavy surge Tuesday night sent sand, water and some 3,000-pound rocks into a boatyard, causing substantial damage and tossing some dry-docked boats off their stands, Avalon Harbor Master Brian Bray said.
The surge also tore away a floating children's swim platform and closed several docks to incoming traffic.
Along the shoreline in Seal Beach, firefighters went door to door, dropping off more sandbags for residents and surveying damage after the initial surge late Tuesday that topped a 2 1/2 foot beach wall, causing flooding in or around the first row of homes. About 100 residences were affected, Orange County Fire Authority Capt. Steve Concialdi said.
Jaime and Blanca Brown's seaside home had a foot of seawater throughout the home, garage and carport. Soaked floor tiles in the hallway were buckled, and a dirty line marked the high point of water in almost every room and the garage. Sodden mattresses and carpets were stacked outside.
The Malibu Pier was closed after pilings were knocked loose. The pier's structural integrity remained sound because of redundancy but people were asked to stay away, State Parks Department official Craig Sap he said.
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