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model Top-Down
service type Emergency Services
country United States
states CA, OR, WA
government type state
license Unknown


ShakeAlert is a real-time earthquake warning system for the west coast of the United States. It’s funded by the U.S. Geological Service (USGS), the states of California, Oregon, and Washington, and the city of Los Angeles, and is housed by the USGS.

A substantial network of seismographs in the three states are used to detect earthquakes, and that data is sent to a processing center that instantly determines the earthquake’s origin and the area likely to be affected. Because of the relatively slow rate at which seismic waves propagate through the ground (between 0.5–3 miles per second), it’s possible to provide early enough earthquake warnings (measured in seconds, not minutes) to allow people to get to safety. ShakeAlert can be used to trigger automated actions, such as alerting people via cell phone, stopping trains, turning traffic lights red, shutting down gas distribution pipelines, etc.

The project started in 2006, with seed funding by USGS. The results were promising enough that, in 2011, the Gordon and Betty Moore Foundation provided $6 million in funding for continued work on the system by universities. Congress provided $13 million in funding in 2014–15, and California provided $10 million the following year. The system first went into use in California, on a test basis, in 2012, and then in Oregon and Washington in 2015. California was the first state to launch a public warning system based on ShakeAlert, in 2019, followed by Oregon and Washington in early 2021.