As the annual Great ShakeOut earthquake drill approaches, Southern California Edison continues to be an important partner in efforts to develop an early warning earthquake detection system and use real-time quake data to improve infrastructure repair following the so-called “Big One” that scientists anticipate will inevitably strike California.

“We conducted a large-scale earthquake exercise this year and the scenario was a 7.8 magnitude earthquake that ruptured along the San Andreas Fault,” said Ken Hudnut, Ph.D., SCE’s seismic expert. “Federal, state and local government agencies, telecommunications partners, other utilities including gas, water, power and transportation also participated to enhance mutual aid coordination efforts to continue preparing for a real-world catastrophic seismic event.”

SCE and the U.S. Geological Survey, along with the Caltech Seismological Laboratory, have collaborated to install more than 50 seismic sensors at SCE substations and other facilities as part of the Southern California Seismic Network, which includes hundreds of additional sensors. These sensors contribute to both the real-time earthquake monitoring system and the ShakeAlert earthquake early warning system, which provide the service needed for earthquake apps that customers can download to receive early warning earthquake alerts, such as MyShake.

“Most of the stations have two types of seismic sensors, one that is very sensitive to very small ground motions to record small earthquakes or seismic waves from earthquakes far away and another that can accurately record very strong ground motions if a large earthquake were to occur nearby,” said Elizabeth Cochran, Ph.D., a USGS observational seismologist. “These sensors can record ground motions strong enough to toss items into the air.”

While SCE’s sensors located across the region provide valuable data to seismologists, the sensors also help the electric company determine the extent of potential damage to its infrastructure and decide how to proceed with post-quake inspections of equipment and facilities.

SCE’s Hudnut spent nearly three decades investigating earthquakes as a geophysicist at the USGS and also conducted seismic research at Caltech. He was one of the USGS’s lead seismic investigators following the 6.4 magnitude Ridgecrest earthquake, known as the foreshock, that occurred on July 4, 2019 in Kern County. He was there when the 7.1 magnitude main shock struck two days later.

“About 15 of us were meeting, to compare field observations on the 6.4 earthquake, in a building near the Ridgecrest City Council chambers, when the 7.1 magnitude earthquake hit. We immediately did ‘drop, cover and hold on’ under a large conference room table. It was a wild ride while the building and everything in it, including all of us, violently shook,” Hudnut said.

In fact, one of SCE’s two new Kern River sensors is located 40 miles away from where the Ridgecrest earthquake occurred. Cochran, Hudnut’s former USGS colleague, continues to lead this research using data from these sensors.

SCE is participating in the Great California Shakeout on Oct. 20 at 10:20 a.m. PST. It is critical to always have a preparedness plan in place before the next earthquake hits. This includes securing items that could topple or become airborne and storing plenty of extra drinking water. More earthquake preparedness tips may be found here.