Technology that automatically alerts trains and applies the brakes for safe, rapid slowing or stopping in the event of an earthquake has been rolled out across Metrolink, the seven-line, 538-route mile regional/commuter rail system that spans six Southern California counties.
Metrolink made the announcement on March 9, the eve of the 90th anniversary of the 6.4-magnitude 1933 Long Beach earthquake along the Newport-Inglewood fault.
Metrolink said its earthquake early warning system is based on an interface between the United States Geological Survey (USGS) ShakeAlert® system and the railroad’s Positive Train Control (PTC) system. Within seconds of an earthquake being detected, ShakeAlert is said to provide the earthquake’s location, magnitude and estimated shaking time so people and systems can be alerted before shaking begins. According to USGS, ShakeAlert is not earthquake prediction, rather a ShakeAlert message indicates that an earthquake has begun and shaking is imminent. ShakeAlert® and PTC work together, allowing trains “to detect and respond as quickly as possible to an earthquake, while also providing enhanced data to support inspection of the rail network and resumption of service following an earthquake,” Metrolink reported.
Implementation of the new technology was supported through a partnership with the California Department of Transportation (Caltrans) and USGS. It debuted on Metrolink in September 2021. “However, at that time, the technology did not yet include automated braking,” Metrolink reported. “Instead, alerts about imminent shaking were received by dispatching staff who used that information to instruct train engineers to manually slow or stop the train if needed.” (Los Angeles County Metropolitan Transportation Authority in 2021 also installed the earthquake early warning system.) Metrolink said it now automates this process by alerting key train personnel and using its PTC system to enforce braking so the train can stop or slow down in response to an alert. “This allows for a faster reaction to shaking, which could ultimately save lives and/or minimize damage,” according to the railroad.
Metrolink’s current earthquake early warning system was piloted along the 91/Perris Valley Line between Riverside and Perris in June 2022. Since then, Metrolink teams have rolled out the technology along segments of its other six lines.
“Safety is at the foundation of all we do,” Metrolink CEO Darren Kettle said. “We are not able to prevent earthquakes here in Southern California, but we now have critical data and technology that allows us to detect shaking earlier, mitigate impacts and save lives. With earthquake early warning technology now available on all of our lines, it gives me great satisfaction to know we are doing everything we can to protect our riders and staff.”