SAN FRANCISCO — California’s coast and its nuclear power plants are unlikely to experience the kind of massive offshore earthquake or sustained tsunami that rocked Japan last week, but more local tsunamis from submarine landslides are possible, according to experts who study West Coast tectonics.
The two nuclear plants on the California coast operate near population centers near the Pacific Ocean. Pacific Gas and Electric Co.’s Diablo Canyon facility is close to San Luis Obispo, and Southern California Edison Co.’s San Onofre plant is just south of Los Angeles.
The generating stations, in operation since the mid-1980s, are built to withstand earthquakes of 7.0-7.5 magnitude, and both have tsunami walls that are 25 to 30 feet tall. But the plants are more threatened by onshore faults than offshore, with Diablo Canyon especially vulnerable given its proximity to the San Andreas Fault.