Quakes Jangle Nerves but Damage to Area Is Minor : Temblors: Some injuries and traffic accidents occur, and hundreds of homes lose power. Grocery stores report a run on water and emergency supplies.

Residents of the San Fernando, Santa Clarita and Antelope valleys were rudely jolted awake and then kept on edge by Sunday’s earthquakes, but authorities said damage in the region was minor--ranging from downed power lines to cracks in water mains and freeway lanes.

Although a handful of residents reported minor injuries, the temblors served mostly as an earthquake preparedness reminder, causing a run on supplies such as bottled water and canned goods in local supermarkets.

Hundreds of homes across the San Fernando Valley were without power for much of the day after the quakes disrupted electrical circuits. Los Angeles Department of Water and Power spokesman Ed Freudenburg said the blackout affected several scattered neighborhoods of about 800 homes each. Crews restored power gradually throughout the day, he said.

Los Angeles Police Officer Bill Mulvihill said broken traffic signals caused dozens of minor traffic accidents around the Valley, none of them serious.

“People just aren’t paying attention,” Mulvihill said. “Most of these people drive the streets every day, so they know where the lights are. But they’re thinking about where they’re going or what they’re going to do, instead of watching where they are going.”

Two eight-inch-wide water pipes were ruptured by the quakes, sending water flooding onto city streets. Freudenburg said pipes burst at Plummer Street and Natick Avenue in Mission Hills and at Hayvenhurst Avenue in Sepulveda. Flows from both pipes were capped quickly, he said.

Los Angeles firefighters responded to reports of fallen utility wires throughout the Valley, spokesman Jim Wells said. Some residents also reported natural gas leaks in their homes.

Police in San Fernando and Burbank also reported scattered power outages in those cities.

The California Highway Patrol reported that one of the quakes caused a two- to three-inch pavement separation in the truck lanes of the southbound Golden State Freeway near the Balboa Boulevard exit north of Granada Hills. CHP Officer Glen Dominguez said the damage was inspected by California Department of Transportation officials, who determined that it was minor and did not warrant closing the lanes to traffic.

“It’s a small crack and they determined it was structurally safe,” Dominguez said. “They will probably replace it later this week.”

On the same freeway, bits of concrete fell from the McBean Parkway overpass in Santa Clarita and landed in the median, but there was no structural damage and the roadway remained open there as well, Dominguez said.

Train tracks near 25th Street East and Avenue S in Palmdale moved about an inch when the earth shook, said Los Angeles County Sheriff’s Lt. Ralph Martin of the Antelope Valley station. The Sheriff’s Department alerted the Southern Pacific railroad, which was going to check the tracks before sending any trains through, Martin said.

Authorities reported few injuries in the region. Los Angeles Fire Department Battalion Chief Robert MacMillan said paramedics treated a handful of people for shortness of breath. “I don’t think we had any kind of a direct injury,” MacMillan said.

Antelope Valley Hospital Medical Center reported treating 10 people with earthquake-related ailments, including fractured toes, a fractured knee, chest pain and shortness of breath.

St. Joseph Medical Center in Burbank treated two people for sprained ankles caused when they ran from their homes during the earthquake.

Several grocery stores throughout the area reported that business was far better than usual Sunday, with worried residents hitting the markets by 8 a.m. to stock up on water and canned goods.

“The store’s very busy and people are filling their carts,” said Gary DeVore, grocery manager at Hughes Market in Canoga Park. “They’ve just said they’re scared. A lot of people are talking about it in the stores and kind of nervously laughing about it.”

DeVore said the store sold 144 one-gallon jugs of water and 144 2 1/2-gallon jugs Sunday morning. People also were asking where flashlights were displayed, he said.

At a Vons store in North Hollywood, people were buying twice the usual amount of water, said grocery manager Manny Orozco. Canned vegetables and spaghetti also were big sellers.

“It’s been crazy,” Orozco said of business Sunday.

Dales Jr. Food Market in Tarzana had a run on batteries, water, canned goods and ice, manager Albert Burke said.

“They’re also buying magazines--something to keep them busy or occupy them,” he said.

Burke said that the store suffered little damage from the earthquakes.

“I lost one jar of prunes,” Burke said.

Times staff writers Henry Chu and Michael Connelly contributed to this story.

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