In October 2017 The National Weather Service and the Redwood Coast Tsunami Work Group in Humboldt County (RCTWG) planned to have a tsunami test.  The test exercises the ability to successfully alert the public to a tsunami risk and, when there is enough time, for coordinated evacuation activities. When a tsunami comes from far away, like Alaska or Japan there can be is enough time to plan for and execute a safe evacuation.

The first time there was a tsunami communications test in Humboldt County was in March 2008, exercising the response system as if a real tsunami had occurred including the Emergency Alert System (EAS). The community worked hard to make sure that everyone was aware of the test, especially people at high risk to not hearing or understanding the alert, the hearing impaired and non-English speakers. The 2008 test only included Humboldt but over time it expanded to Del Norte and Mendocino Counties. The test has been run each year since 2008 except 2011, when there a real tsunami from a Japanese earthquake generated a real alert.

This year the RCTWG decided to change the timing of the 2017 test exercise to October, to coincide with the Great ShakeOut earthquake exercise, the same as communities in coastal Oregon and Washington.  But a successful tsunami test depends on the citizens understanding what to do when the alert sirens sound and they receive evacuation notices.  This requires education on what to do, and to insure people know it will be a test, and only a test.  The fires in northern California made it hard to do a test, not only because many of the emergency personnel were actively fighting fires, but also because the citizens might think that sirens sounding and the EAS system going off meant a real disaster was about to hit.

The communities still took part in the Great ShakeOut on Thursday Oct. 19 and practiced DROP, COVER and HOLD ON.  Everyone living or traveling in coastal California should know what to do in the case of a tsunami, they can come suddenly and often without warning, especially when triggered by a local earthquake. You can find earthquake and tsunami preparedness information in “Living on Shaky Ground: How to Survive Earthquakes and Tsunamis in Northern California” available here along with other preparedness information.

It pays to be prepared, as the people of the north coast know well, Mother Nature will always surprise.


This post is based in part on a story filed in the Eureka Times Standard by Professor Lori Dengler, a Commission Partner and emeritus professor of geology at Humboldt State University. Professor Dengler is the co-author of “The Extraordinary Voyage of Kamome,” a tsunami education book sponsored under a Seismic Safety Commission grant.