SIGNAL LIGHTS FAIL, TRIGGERING TRAFFIC NIGHTMARE.

Byline: Dana Bartholomew and Orith Goldberg Staff Writers

Rush-hour Wednesday evening turned into a massive traffic jam on streets and freeways across the San Fernando Valley when hundreds of traffic signals were knocked out.

A brief power interruption at 4:10 p.m. caused about 300 of the Valley's estimated 1,000 traffic signals to flash red, stalling traffic to a crawl at many intersections and backing up commuters at freeway ramps.

At first Department of Water and Power officials said they thought the problem had been caused by a lightning strike, but they later said the exact cause of the equipment failure was under investigation. They said it might have been related to heavy use of electricity during the hot weather.

Each of the lights has to be reset manually after an outage so field crews from the L.A. Department of Transportation were working feverishly to reset each of the computerized signals - a time-consuming task that prolonged the traffic chaos into the night. Lights on the Westside, Hollywood and some areas of Southwest Los Angeles were also out.

Some intersections slowed to gridlock as drivers honked and tempers flared.

``The freeways were packed,'' said Officer Karen Faciane at the traffic management center of the California Highway Patrol.

She said there were also more traffic collisions than usual on the freeways, but she could not say whether they were related to the light problem on the surface streets.

Frustrated motorists wondered how a brief power interruption could cause such a widespread problem.

``They should be prepared for this stuff - there's no reason for this,'' said Kenneth Cregger, 33, of Canoga Park, whose pickup truck stood mired behind an MTA bus.

Kris Corbett, 20, of Woodland Hills was also critical of the city's transportation system. A half-hour earlier, he'd experienced the brownout, although the surge didn't affect his office computer.

``They should have some kind of protection against power surges,'' Corbett said from his car. ``The traffic's going to be backed up for hours and hours and hours and hours.''

Slava Blinov, a taxi driver, said his company would probably lose money because of the problem.

``It was impossible to make normal taxi business at this hour. We lost customers and business. I think everybody who called at that time probably won't use us again.''

Police simply did not have the manpower to send officials to every intersection that was without a signal.

``It was all over Van Nuys,'' said Los Angeles police Sgt. Richard Thomas.

Valley Traffic Officer Michelle Lopez said she had never seen anything like it before. ``It's pretty bad because people can't get off the freeways.''

Officials said the problem might have been related to a lightning strike that came from a storm that passed through the mountains in the Antelope Valley on Wednesday, headed northwest toward Santa Barbara and San Luis Obispo.