Tsunami Preparedness in Washington


You’re walking along the beach and suddenly the ground shakes and moments later the water recedes. Do you know what to do? If you’re on the water front and the sirens go off, do you know what it means? The open ocean of the Washington coast is subject to two types of tsunamis. The first is a near-field tsunami generated from earthquakes throughout the Cascadia Subduction Zone. Depending on where you are: on the coast, or inland near Port Townsend, it can be 30 minutes to over an hour until tsunami waves arrive. In that case, a person on the beach would have to react on their own to recognize natural ques such as ground shaking and quick recession of water. The second tsunami source threatening the coast of Washington is a far field event caused by an earthquake on the Pacific Ocean margin, such as Alaska or Russia. There would be hours before the event showed. The sirens would go off and you would have support from local emergency management to evacuate the area. The overall risks to each community are in the hands of the communities themselves. There will be warnings for both types of events. For local Cascadia Subduction Zone event, there will be natural warning signs: The ground will shake; Water may recede from the shoreline. In those instances, you need to be prepared to move inland or to high ground immediately. From a distant event such as one that would occur in Alaska or Japan, there will be more time to issue official warnings. It would be broadcast through local media, NOAA weather radio, and the all hazard alert broadcast (AHAB) sirens along the coastline. We have a multilayered warning system because we recognize people are not able to hear a warning by just one single source. One single source creates gaps in the warning network. We stress people need a NOAA weather warning radio in their home so they can hear that inside their house. We also partner with the local fire departments. In certain instances, we ask them to drive the beach and issue warnings to people actually on the beach. If you were on the coast and received a tsunami warning, you would need to move to higher ground immediately. That tsunami warning can last up to 24 hours. In some cases, like a local event, you may not be able to get to 50 ft above sea level (a rule of thumb for high ground). You may only be able to get as high as the second story of your home, or a neighbor’s home if you don’t have a second story. It is obviously safer than staying at sea level. Many times, tsunami waves come is series of 6 to 8 waves. We can’t currently predict which wave will have the greatest impact and be most dangerous. We ask that people stay at high ground for a minimum of 24 hours. You need to be personally prepared for that event. An evacuation kit should contain those items that you feel are necessary to sustain you for 24 hours. A kit is basic: a small first aid kit, medications you or your family might need in 24-hour period, granola bars, bottles of water. Every family needs to think this over carefully and make plans that are suitable specifically for their family. You have to be prepare to be able to move quickly. If the ground shakes, you should first drop, cover and hold on. Once the ground stops shaking, you need to evacuate inland or to higher ground. Look around and be familiar with your environment. Be aware of where you are. Look for signage in your community. Look for low-lying areas that may be impacted by tsunamis. Look for directions that tell you where to go to safety. Follow the evacuation road signs. Look for the walking routes – they may be different. In our community we have the “yellow brick road” because it helps people remember that’s the evacuation route. Look for assembly areas. Go to the assembly areas. Look at the signage there. The signage may provide valuable information such as GPS location, elevation, and numbers to help others identify your location. Also in our communities, we have evacuation maps. They tell you where driving and walking evacuation routes are. Any time you’re involved in an emergency, such as a tsunami, the best thing you can do is plan in advance. It helps you remain calm. It helps you go through your plan. I encourage people to practice their plan; practice their evacuation route. When the day comes, you know what you’re doing. You feel in control. If you feel you’re in control, you remain calm. We can’t control the tsunami hazards on the open ocean coast of Washington, but we can hopefully manage the vulnerability of individuals and communities to these hazards. We can understand if we’re in a tsunami zone whether we’re at work, home or out playing on the coast. We can have a NOAA weather radio to inform us if a far field tsunami is on its way. We can understand natural signals like ground shaking and shoreline recession if a nearby occurs. We can practice our evacuation routes; know where they are; practice them with family and neighborhood members. We can look around and see if others near us might need help in evacuating, such as people in daycare or adult residential care. We can work with local business owners to help them understand how tourists may need assistance. Although we can’t control tsunamis from hitting the open coast of Washington, we can reduce our vulnerability by taking time now to educate and prepare ourselves.

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