California ramps up construction of statewide seismic warning system

SAN DIEGO (KUSI) — An early warning system for earthquakes is quickly taking shape in California.

Californians live in constant threat of some day experiencing the big one. Now, after years of research and planning, a system for earthquake alerts could be functioning in a limited capacity as early as next year.

Pat Abbott is a geologist who taught for years at San Diego State. With an initial $10 million in funding from Sacramento, the U.S. Geological Survey is building the system that will rely on a network of sensing stations that are currently being installed around the state.

In a computer simulation, Abbott shows what might happen if a quake occurs on the southern end of the San Andreas Fault. How long would it take for the tremors to move north into San Diego and on to Los Angeles?

In this scenario, a sophisticated warning system might give some people as much as 45 seconds before the shaking begins.

In the 2014 Napa Quake in northern California, seismic sensors gave researchers in San Francisco about eight seconds of warning before the tremors began. 

Think of the system as having two parts. First, senors that are being placed underground would detect the quake and then turn that information around to send out an alert. 

When a quake first hits, the initial shaking is called the ‘P’ or primary waves, but Abbott said it’s the secondary phase, the "S" waves, and the tremors after, that inflict the most damage.

San Diego sits on top of an active fault called the Rose Canyon Fault Zone, which runs through and into San Diego Bay. 

But a quake that happens here would be too close for sensors to deliver any advance warning to San Diegans.

Researchers have made progress on building this kind of sensor network in Oregon and Washington State. 

In California, the hope is to roll the system out in phases, going from a limited to a full public alert system. The cost is estimated at $38 million for building it and about $16 million a year for its maintenance. 

Categories: Local San Diego News