Editorial: L.A.’s new earthquake alert app is great, but shouldn’t everyone know when a quake is seconds away?

You are now just a smartphone app away from knowing within seconds — if you’re lucky, tens of seconds — when an earthquake with a magnitude of 5.0 or higher is about to rattle Los Angeles County.

ShakeAlertLA, an app commissioned by the city of L.A. for use in the entire county of Los Angeles, can now be downloaded — for free! — to Android and Apple devices. A network of ground sensors, operated by the U.S. Geological Survey, detects the earliest indications of shaking. The app then sends an immediate message that an earthquake is on the way and the kind of shaking to be expected (light, moderate, or severe). It might not be perfect — there could be false alarms, or, conversely, failures to detect a quake. But the technology has been used, mostly successfully, in other countries and should work here as well. It is the first such warning system in the United States and a tool to help us deal with the inevitable big one.

Kudos to the L.A. city government for rolling it out and taking care of the kinks along the way. When there wasn’t enough federal money for all the necessary ground sensors in southern California, Mayor Eric Garcetti found $6 million to finish putting them in. When the city needed $300,000 to create the technology for the app, it got grants and hired AT&T.

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But shouldn’t there be an alert system for the rest of California and the West Coast? The state and federal governments should be financing the necessary expansion of the ground sensor network along the entire coast. With sensors in place, other West Coast municipalities or, better yet, the state itself, could set up quake alert apps. Or there could be some kind of wireless emergency alert system (like the Amber Alerts) that reaches all phones unless you opt out. The technology in the Amber Alert system is too slow right now to make it useful as an earthquake warning system. But it could be improved.

And meanwhile, let’s get on with retrofitting buildings to better withstand quakes. The city made a good start by mandating retrofitting of vulnerable wood and concrete structures. But concrete retrofitting, in particular, is expensive and proceeding at a glacial pace. Assemblyman Adrin Nazarian (D-North Hollywood) may re-introduce a 30% seismic retrofit tax credit that was vetoed in 2015. That’s an investment worth considering.

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