Earthquake Early Warning System

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The high cost of earthquakes in California has been due in part to their unexpected nature. An earthquake early-warning system allows emergency workers time to prepare for an imminent earthquake, which reduces its repair costs. The cost of such a system is easy to justify since it’s typically much less than the cost of repairing an unexpected earthquake in California. Possible sources of funding for an earthquake early-warning system include the State of California, the Federal Government and a California referendum.


The effectiveness of an earthquake early-warning system is based on the fact that earthquakes travel at the speed of sound while the signals from earthquake sensors travel at the speed of light. A magnitude 5.1 earthquake originating near La Habra, California occurred on the evening of March 28, 2014. A prototype of an earthquake early-warning system provided seismologists in Pasadena with about 4 seconds of advance warning of this earthquake. The same system also gave seismologists a two-second warning for a 4.4 earthquake that occurred earlier in March near Westwood.

The U.S. Geological Survey is testing this prototype for the purpose of creating a network of earthquake early-warning systems throughout the state of California. The completed network could provide Los Angeles with up to 50 seconds of warning for earthquakes originating along the San Andreas Fault. This advance notice would allow engineers to slow down trains to avoid derailment, firefighters to open the doors to firehouses and surgeons to remove scalpels from patients.

The USGS is proposing that the earthquake early-warning system be built into the California Integrated Seismic Network, which already has almost 1,000 sensors. The CISN still requires an additional 400 stations and 200 machines to become an effective early-warning system for earthquakes. Users could install software on their computers or apps on mobile phones that would notify them in the event of an earthquake in progress. Similar software would alert motorists, hospitals and emergency workers.


Cost is the primary obstacle against implementing an earthquake early-warning system. The USGS estimates that this system would cost about $80 million, according to a plan that it announced on 01/27/2014. These funds would be primarily used to maintain the stations needed to make the system reliable. For example, a 6.8 earthquake occurred off the northern coast of California on March 10, 2014. The seismic warning station nearest the epicenter of this quake didn’t detect the tremor because it wasn’t functioning at the time.

State Representative Peter Defazio reports that only $10 million has been spent on developing earthquake warning systems since 1999. Government spending on this technology has been limited to about $400,000 per year, although researchers received a grant from the Gordon and Betty Moore Foundation worth about $6 million in 2011. Additionally, the proposed federal budget for fiscal year 2015 provides $850,000 for continuing research on these systems.

State Senator Alex Padilla is sponsoring proposing legislation to create the statewide network, which would be the first of its kind in the United States. He believes California will eventually have an earthquake warning system, although he doesn’t know if this happen before the next major earthquake. Earthquake experts have said the system could be operational within two years once funding is available, although a complete network along the West Coast will require about five years to complete.


A large major quake in California can easily cause billions of dollars’ worth of damages. For example, the last major quake in California occurred in 1994 and originated near Northridge in the San Fern ando Valley. It was a 6.7 quake that caused $20 billion worth of damage and killed 57 people.

Seismologists have made many attempts to predict future seismic activity along the San Andreas Fault. The latest of these studies was released in January of 2014, which discusses the possibility of a major quake that would be felt from San Diego to San Francisco. Senator Padilla has said that a statewide network of earthquake sensors could save many lives and reduce the damages that a quake could cause. An earthquake early warning system would only need to reduce the damage from an earthquake by a small fraction to more than pay for itself. Padilla added that he was surprised that funding has been so difficult to obtain, and that state legislators will be kicking themselves if they don’t begin moving more swiftly on this issue.


California lawmakers passed a law in 2013 that prevents the government from using the General Fund to finance such a system. This legislation requires the Office of Emergency Services to obtain funding for an earthquake system from other sources, including public and private sources.

California Representative Adam B. Schiff (D-Burbank) has circulated a letter requesting the appropriations subcommittee of the House Interior to contribute $16.1 million towards an earthquake system for the 2015 fiscal year. Democrats from California, Washington state and Oregon signed the letter, although no Republicans from California did so. Legislators outside of California may also be reluctant to allocate funding for earthquake detection systems, since they tend to view earthquakes as a California problem. In addition, Professor Thomas Heaton of the Earthquake Engineering Research Lab in Caltech reports that seismic activity in California has been relatively quiet for the last few years, making it difficult to regard earthquakes as an urgent problem.

The issue of funding an early warning system for earthquakes may become an issue for Representative Ken Calvert (R-Corona), who recently became the chairman of the Interior subcommittee. Calvert has said that he will support funding for the USGS’s earthquake programs if he can be convinced that it works. He added that he is concerned about funding a program that later turns out to be ineffective.

Referendums calling for a popular vote are another option for financing earthquake detection systems. Ballot measures have a record for effecting major changes in California law.  More information is available at California Institute of Technology  and USGS.

Karl D. Susman