Earthquake Early Warning coming to Washington



Posted on April 19, 2014 at 10:31 AM

Updated Saturday, Apr 19 at 11:46 AM

SEATTLE --  It's called "earthquake early warning” - a network of seismometers, computers and software  designed to work together to give people time to brace for earthquake shaking.

Scientists say think of it like lightning and thunder.  The further you are away from the lightening, the more seconds there are between seeing a flash and feeling the thunder.

If you're sitting on top of the quake's epicenter, there is no warning, but the warning will be longer the further you are from where the quake starts.

The University of Washington, Cal Tech, and the University of California at Berkeley have been working together for years bringing earthquake early warning to the West Coast.  Pieces of the system are starting to go into effect in the more active area of Southern California.

Washington faces a risk of bigger but less frequent mega-quakes off the coast that creates different requirements, but it should start seeing pieces of the system begin operating later this year, said state seismologist John Vidale, who also leads the Pacific Northwest Seismic Network based at the University of Washington.

"It's about noticing earthquakes fast and telling people the shaking is on the way," said Vidale.

A system for the general public will take longer, but an automated system relies on the "P" or less damaging primary wave from a quake that moves much faster than stronger "S" waves that cause most of the damage. 

Those signals could do things like trigger gates to keep more traffic from driving onto the Alaska Way Viaduct, slow down or stop trains before rails can break and bridges collapse.  The doors to fire stations would automatically open so trucks needed for the response would be less likely to be trapped inside.

A test of a similar system came Friday morning in Mexico, after a 7.2 magnitude struck 170 miles from Mexico City. Vidale says the more basic early warning system helped get the word out as much as 60 seconds before parts of the city were hit.

Mexico City saw 9,500 people killed in a giant magnitude-8.1 earthquake in 1984. It was a much larger quake, but centered even further away that the 7.2 that hit Friday morning. This time there are no reports of major damage or casualties.

Vidale estimates the U.S. West Coast early warning system will cost around $16 million a year to operate.

"And if Congress wants to do it, it will be working in just a few years," Vidale said.