Earthquake Warning System passes test in Belfair earthquake

More than 2,500 people reported feeling a magnitude 4.1 earthquake that center in Belfair on Wednesday night.

It’s is the biggest to hit the Pacific Northwest since the 4.8 quake that centered in Victoria, B.C. in December 2015.

KIRO 7 talked to UW Seismologists at the Pacific Northwest Seismic Network on Thursday about what they learned from the quake.

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Dr. John Vidale told KIRO 7 people reported feeling shaking as far north as Canada, as far west as the Washington coast, and as far east as Ellensburg.

The Belfair quake was 10 miles deep and didn’t cause any damage.  But it did trigger the Earthquake Early Warning System being developed at the PNSN.

>> Magnitude 4.2 earthquake hits near Belfair

KIRO 7 Morning Anchor John Knicely asked Vidale how well the system worked.

“As soon as the P-Wave hit three or four stations it made an estimate of how big the earthquake was. That took just six seconds. If it was a bigger one it means people would have had 10 or 15 seconds to know some shaking might be coming.”

Vidale told KIRO 7 that's enough time reduce the impact of the earthquake 20 percent to – 30 percent, which would give people time to position themselves and trigger automatic measures like slowing trains.

The warning system is still being developed with the goal of getting that info directly to your phone.

“Everything basic to the system worked,” said Vidale.  “So it verified we're in good shape.”

Cox Media Group