Shaker Alert System Developed in Pasadena Gets Tested

Published : Friday, March 29, 2019 | 4:43 AM

On August 28, the ShakeAlert system sent out is first actual alert in Southern California giving Pasadena scientists two seconds of warning before the effects of a 3.5 temblor centered near La Verne were felt here.

California’s fledgling ShakeAlert early warning earthquake system, partly developed by Caltech and the U.S. Geological Service (USGS) in Pasadena, was given a trial run March 27.

The test was done in coordination with the California Office of Emergency Services (CalOES) and the City of Oakland. Other collaborators on the project include past University of California Berkeley, the University of Washington, and University of Oregon.

At 11 a.m., on March 27 a technician at USGS Pasadena pressed a button to send out the test alert, and about four seconds later, someone within a 60-block area of Oakland, 370 miles away, became the first to receive the first alarm on his smartphone with the message “This is a test of the California Earthquake warning system. No action required. This is a test.”

Robert De Groot, Coordinator for Communication, Education, and Outreach for ShakeAlert at the USGS Earthquake Science Center in Pasadena, told KABC a wave of text messages and alarms hit other cellphones in the selected test area within milliseconds, and people participating in the test recorded the exact time they received the alert.

“There was a wave, they all came at once and then there were several devices that came in many seconds later,” De Groot told KABC. “It tells us that we have to look at what were the differences, some of the phones were older, some of the oldest didn’t get the signal at all, phones without SIM cards.”

The information will help USGS and CalOES determine how long it took for the alerts to reach smartphones in the selected area in Oakland, and find out what needs to be improved in the alert system.

USGS started developing ShakeAlert in 2006 with the help of its partners including Caltech. Since that time, the project has received more than $100 million in funding from the federal government, the CalOES and private sources such as the Gordon and Betty Moore Foundation. In January, Gov. Gavin Newsom set aside $16.3 million in his first budget to complete the alert system.

In a real-world earthquake event on the West Coast, seismic sensors at or near the epicenter will send the data to USGS monitoring centers in Pasadena, Berkeley, Menlo Park or Seattle, where computer algorithms will then analyze the data to rapidly identify the epicenter and the strength of the earthquake, and decide whether the temblor is powerful enough to warrant an alert.

If the sensors detect an earthquake magnitude of 5 or greater, a message is sent to the Federal Emergency Management Agency for distribution.

ShakeAlert’s developers are confident the system could give people at least a few seconds to “duck, cover and hold” before the shaking comes, and could eventually allow authorities to slow down trains or even pause surgeries inside hospitals.

Last August, ShakeAlert showed promise when a 4.4-magnitude earthquake rattled La Verne.

It was able to give nearly five seconds of warning for areas 20 miles away, officials said. Los Angeles, which was 28 miles from the epicenter, received the alert 8.3 seconds before the tremors reached the city.

USGS estimates ShakeAlert, which targets the installation of up to 1,600 sensors all over the West Coast, will cost $39.4 million to build once completed, as well as $28.6 million annually to operate.

blog comments powered by Disqus