Today, on the 30th anniversary of the Loma Prieta earthquake, Governor Gavin Newsom, State Senator Jerry Hill, and a group of scientists announced the official launch of California's Earthquake Early Warning System.

The project, dubbed ShakeAlert, has been in the works since 2006 and has faced some embarrassingly long delays and funding issues. I say embarrassing because similar systems have been in place in Japan and Mexico for years — the 2011 Japan earthquake came with a warning several seconds ahead of it in Tokyo, for instance, after the Japanese began building a warning system following the Kobe quake in 1995.

But now, as ABC 7 reports, the alert system is ready to roll out for Northern California after already being put in use in the Los Angeles area. It works like this: In the moments before an earthquake's weaker initial waves ripple out from its epicenter, sensors throughout the region will detect those waves and send alerts out to cellphones, Amber Alert-style, giving people a few seconds of warning to take cover before the stronger S- or surface waves hit.

The warnings can also come through the MyShake app, now downloadable for iOS and Android. The app also serves to collect data after an earthquake on how far and wide the shaking was felt.

Until today, as the LA Times explains, only people with the city of Los Angeles’ ShakeAlertLA app had access to such an early-warning system — though that system failed to send any alerts about the 6.4M quake that struck in east of LA County on July 4 or the subsequent 7.1M quake, because it was only designed to warning of severe shaking within LA County.

Based on the reaction by the public to the lack of warning about those quakes, the MyShake app has now been calibrated to send warnings about any quakes over 3.0M, which would be expected to be felt by people indoors. The Amber Alert-style text alerts will only be sent for shaking of 4.0M or above.

"We cannot promise you a perfect system," says Richard Allen, director of the Berkeley Seismology Lab, speaking to the LA Times. But, he says, based on tests, "the system seems to be performing reasonably well."

California lawmakers have budgeted $7 million this year to promote the MyShake app, and the project has been operating since June on $1.5 million in funding from the Office of Emergency Services. Startup funds were provided by a variety of public and private sources, including the Gordon and Betty Moore Foundation, as the LA Times reports.

The MyShake app operates through the cloud, and currently relies on hundreds of sensors installed throughout the state of California by the U.S. Geological Survey. Eventually, the USGS wants to install more sensors in remote and rural areas of the state, as well as expanding the system to Oregon and Washington.

Previously: Earthquake Early Warning System Still Isn't Ready, $26M And 11 Years Later