California Railroad tests use of earthquake alerts to stop trains
A regional passenger rail service in Southern California said Thursday it was testing technology that would use the West Coast Earthquake Early Warning System to automatically slow or stop trains before tremors begin.
The five-county Metrolink system said the technology is a step up from a previous version rolled out in September 2021 that sends automated messages asking train crews to slow down or stop but has no automated braking.
The new technology is an interface between the ShakeAlert system’s earthquake warnings and a system called Positive Train Control that is designed to prevent train collisions, overspeed derailments and other dangerous situations.
“The combination of ShakeAlert and PTC is truly a game-changer for Metrolink,” railroad CEO Darren Kettle said in a statement.
ShakeAlert, operated by the US Geological Survey, universities and other partners, uses a network of sensors to detect the onset of a large earthquake and send alerts to the affected area before the shaking arrives so that people and systems can take precautions.
The system’s coverage area includes California, Oregon and Washington.
Positive train control uses GPS, radio and computers to monitor train positions and speeds. It was designed to reduce accidents involving human error by automatically braking.
In addition to stopping trains that may be colliding or traveling too fast, the system can prevent trains from entering tracks undergoing maintenance or heading in the wrong direction due to shunting errors.
Metrolink said the new technology was being tested on its route between the towns of Riverside and Perris, about 80 kilometers east of Los Angeles.
Metrolink operates 538 miles (866 kilometers) of track in Los Angeles, Orange, Riverside, San Bernardino and Ventura counties. It had 12 million annual boardings before the COVID-19 pandemic.