From Pacifica to Pescadero, eight loud sirens near beaches cracked the normally quiet morning Wednesday, signaling the first test of a newly upgraded San Mateo County tsunami warning system.
“It scared the heck out of me,” said forty year resident Diana North. “It went on way long”.
Eighth grader Jerry Sheng described the new sound to KTVU as “kind of like a police siren.”
San Mateo County officials called the test Wednesday morning a success.
After a $160,000 upgrade to electronics and communications gear, it was clearly audible in the inundation zones, according to Office of Emergency Services (OES) District Coordinator Jeff Norris.
But KTVU found some people later that day who said they did not hear the warning.
“I was asleep and did not wake up at all,” laughed Sara Linscheid, who added that she works nights and sleeps soundly.
In an actual tsunami, the siren would sound for three minutes at 20 minute intervals, and there would be live voice instructions in English and possibly other languages, according to Norris.
“That would continue for the last two hours before we believe a tsunami is to reach us,” said Norris.
Because of the fault geology off the Bay Area coast, residents likely would have an hour or two warning, according to experts. The significant tsunami threat is from a big undersea earthquake in the Aleutian Island or off the Oregon and Washington coasts. Even then a fifteen foot or higher tsunami could strike the Bay Area coastline with devastating effect.
“Flowing water has lots of power. It can knock over buildings, pick up cars and rocks. It’s quite deadly,” explained UC Santa Cruz Professor and geophysicist Steven Ward. “There’s all kinds of material in the water, it’s more like concrete than water.”
Ward’s research has shown barrier beaches, such as the one at Linda Mar, were especially vulnerable and no match for a tsunami.
“The ocean comes up, comes up and comes up for 10 to 15 minutes,” explained Ward. “It’s not really like a wave, it’s more like a flood.”
Coastal siren operators receive their tsunami warnings from federal disaster officials. San Mateo County officials told KTVU that they planned to test sirens the morning of the first Wednesday of each month.
If local residents hear the siren any other time, they should be ready to evacuate.
Watchdogs are questioning an exclusive agreement between the City of Oakland and a non-profit group, tapped to lead a multi-million dollar project to redevelop the area around the Coliseum BART station.