triggered tsunami. Within an hour of the earthquake, the WC/ATWC canceled the warning for the coast areas of British Columbia, Oregon, Washington, and California.

This tsunami warning came only six months after the horrific tragedies, which took place off the coast of the Indian Ocean during the 2004 tsunami at a time of heightened national fear of tsunami activity. This warning would be the first to be issued for the West Coast for a regional event. Adding to the urgency of decision making action by the TWC was the size and location of the earthquake, the potential for either earthquake- or landslide-generated tsunamis, and the need to issue a statement before potential inundation occurred along the coast (within minutes of the earthquake).


The June 14, 2005, Gorda Plate earthquake (M7.2) violently shook a wide area of Del Norte and Humboldt Counties, including the cities of Eureka and Crescent City. In assessing the consequent actions at the state and local levels to the tsunami warning it is critical to recognize that the “event” was both a local, widely felt, potentially damaging earthquake, and a potentially damaging near-field tsunami that was the subject of a tsunami warning issued by the WC/ATWC. As noted above, within five minutes of the earthquake, officials at the WC/ATWC issued a tsunami warning to the California State Warning Center (CSWC) both verbally over the National Warning System (NAWAS) and as printed copy over the National Oceanic and Atmospheric Administration/National Weather Service (NOAA/NWS) Weather Wire. These messages were communicated verbally to impacted counties over California’s equivalent to NAWAS, the California Warning System (CALWAS) and by the California Law Enforcement Telecommunications System (CLETS), a teletype service connecting local law enforcement agencies to the California Department of Justice. At the same time that official notification to the CSWC and local governments was occurring, the WC/ATWC notification was being automatically transmitted over the Weather Wire to subscribers of email and pager notification services, over the Emergency Managers Weather Information Notification (EMWIN) service, over the California Emergency Digital Information Service (EDIS) to radio and television newsrooms, and over the California Integrated Seismic Network (CISN) Display to local emergency operations centers.

The WC/ATWC warning was transmitted over the California Law Enforcement Telecommunications System to 22 coastal counties (15 counties directly on the coast and 7 counties that would be impacted by flooding in bays and estuaries), California Highway Patrol (CHP), and State Parks and Recreation. Within 10 minutes following the notification over CLETS, CALWAS was used to issue an initial warning to local emergency responders in the surrounding coastal area. Unfortunately at the time in which this took place, the CSWC was not sufficiently staffed, leaving only two employees to handle the surge of emergency calls. The local recipient of the CSWC notifications is the designated Public Safety Access Point (PSAP), usually the county 911 office and/or fire, law, and emergency medical dispatch, and for the CLETS teletype messages, local law enforcement agencies.

CSWC and Office of Emergency Services procedures provide for secondary notification and

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