Following a 4.3-magnitude earthquake and a 3.5 aftershock in Contra Costa County on Tuesday, 50 technical partners of the U.S. Geological Survey’s ShakeAlert early earthquake warning system were successfully notified, according to a coordinator with the program.
While the system is not yet available to the public as a mobile application for the region, if it was, many residents across the Bay Area would have received a warning as soon as the shocks began at the origin near Blackhawk, 20 miles east of Oakland, according to Robert de Groot, coordinator for communication at ShakeAlert.
Earlier this month, Los Angeles County residents questioned the accuracy of ShakeAlert after the county’s mobile alert system failed to warn the public when two earthquakes with magnitudes 6.4 and 7.1 hit Southern California.