PORT ANGELES — A tsunami rarely arrives as a single cinematic wall of water rolling toward shore like a towering wave in a disaster film. Instead, it comes in waves — sometimes for hours — with powerful currents capable of ripping boats from their moorings and scouring seabeds before surging back again.
That was the message local and state emergency officials delivered Tuesday night at a Tsunami Hazards and Risks presentation at Field Arts & Events Hall, where residents were briefed on what a tsunami event would look like and how to prepare for that eventuality.
Hosted by the Port of Port Angeles, the event brought together representatives from the Washington Emergency Management Division, the state Department of Natural Resources, the U.S. Coast Guard, Clallam County Emergency Management and the city of Port Angeles.
The presentation focused on two scenarios that pose the greatest risk to the area: a distant tsunami generated by an earthquake in the Pacific Ocean, and a local tsunami caused by a significant earthquake — aka “the big one” — along the Cascadia Subduction Zone off the coast.
“There’s a 10 to 30 percent chance within the next 50 years that we’ll see a major earthquake on this fault system,” said Ethan Weller of the Washington Emergency Management Division.
“The last great rupture occurred in 1700, and these major events happen every 300 to 600 years.”
Tsunamis arrive as a series rather than a single surge and can last from 12 to more than 24 hours. The first wave often is neither the highest nor the most destructive; later waves — sometimes the sixth or seventh — may be more powerful.
Unlike wind-driven waves, tsunami waves move extremely fast, carrying debris, hazardous materials and anything else in their path.
Washington is “earthquake country,” emergency officials said, with the second-highest earthquake risk in the nation and multiple tsunami threats.
“About 80 percent of tsunamis are caused by earthquakes,” Weller said.
According to Washington Geological Survey, a major Cascadia earthquake — capable of reaching a magnitude 8.0 or higher — could send a tsunami to Port Angeles in about 50 minutes. In some areas of the harbor, water could begin pulling out as soon as 15 minutes after the quake begins.
High-resolution modeling of a Cascadia event shown on Tuesday illustrated how tsunami waves would wrap around the end of Ediz Hook, cross the harbor, slam into the waterfront and inundate downtown Port Angeles with 10 to 20 feet of water — only to recede and return again and again.
Distant tsunamis, such as those generated by earthquakes along the Alaska-Aleutian subduction zone, can take more than four hours to reach Port Angeles. They typically produce less inland flooding than local tsunamis, but they can still generate dangerous currents capable of damaging docks and boats.
Current speed is a key factor in determining damage, said Daniel Eungard of the Washington Geological Survey, with the strongest capable of pulling large boats from their moorings and destroying maritime infrastructure.
John Wayne Marina appeared comparatively sheltered in some scenarios due to local geography, although hazardous currents could still develop near its entrance.
Because currents and waves can persist for more than 48 hours after a tsunami begins, people are urged to remain in a secure location until authorities declare it safe to return to lower ground.
While the instinct may be to jump into a vehicle and try to flee when the earth starts to shake, officials said walking to high ground of at least 30 feet is safer. Earthquakes can buckle roads, damage bridges and bring down power lines. Keeping roads clear can help emergency responders and people with mobility challenges.
For boaters, officials emphasized that hazards extend well beyond wave height. Maximilion Dixon with the Emergency Management Division said some of the biggest risks include unmoored vessels, logs and floating debris.
“Make sure that you always face into the waves,” Dixon said. “Facing into the waves that are coming in, facing the wave when they’re going out, and so on and so forth.”
Officials stressed that preparation is an individual, family and community responsibility. Emergency managers recommend having at least 30 days of food and essentials in case the area is cut off from land transportation.
Former state Rep. Jim Buck, an emergency management volunteer, urged residents to think beyond immediate evacuation and prepare for prolonged disruption.
“The objective here is not to see who gets their feet least wet,” Buck said.
For people living in tsunami hazard zones, Buck recommended making arrangements to stay with friends or family outside the zone and planning to be self-sufficient for weeks rather than days.
“Almost everybody survives,” Buck said. “The question is how prepared you are for what comes after.”
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Reporter Paula Hunt can be reached by email at paula.hunt@peninsuladailynews.com.
Tsunami Preparedness
1. Have a clear evacuation plan. ow the risks, decide in advance where to go and how to get there, and make sure family members understand their roles so no time is lost during an emergency.
2. Assume an earthquake will be the trigger.
3. Prepare differently for local vs. distant tsunamis.
4. Reduce maritime and waterfront risks ahead of time.
5. Be ready to be self-sufficient for weeks.
General information and how to prepare for a tsunami can be found at mil.wa.gov/tsunami.
Emergency resources
Clallam County Emergency Management and the city of Port Angeles use Everbridge as their emergency notification system. The service delivers critical alerts — such as severe weather, road closures and utility outages — by phone, email or text, based on residents’ preferences. Sign up for it at www.cityofpa.us/1418/Emergency-Alerts.
Residents can participate in the Community Emergency Response Team (CERT) Program that teaches people how to prepare for disasters. It provides hands-on training in basic response skills, such as light search and rescue, team organization and disaster medical care. For information about upcoming classes, email justine.chorley@clallamcountywa.gov.
The Clallam County Disaster Assistance Response Team (DART) is a volunteer airlift group that operates out of William R. Fairchild International Airport in Port Angeles. It helps communities and emergency responders cope with local disasters, from moving medical patients, to delivering supplies to performing aerial reconnaissance. It can be reached at info@clallamdart.com.
