The recent seismic event off the coast of Russia, which sent a minor tsunami ripple to the Pacific Northwest, serves as a stark and urgent warning for residents along the coastline and the lower Columbia River. While the immediate impact was minimal, experts are emphasizing that this incident should be viewed as a crucial practice drill for the region’s inevitable encounter with a major megaquake and subsequent catastrophic tsunami.
Daniel Eungard, who leads the tsunami hazards program for the Washington Geological Survey, typically receives numerous tsunami alerts that prove to be inconsequential. However, the alert following the Tuesday earthquake off Russia was distinctly different, prompting him to immediately resume work for an extended period, signaling the gravity of the situation, even if the actual local impact was small.
The subtle effects of this distant quake were still felt. Captain Dan Jordan, a ship pilot and administrator for the Columbia River Bar Pilots, recounted delaying a commercial ship for three hours before allowing it to enter the river’s dangerous mouth. This precaution highlights the significant operational disruptions a larger tsunami event would inevitably cause, impacting vital trade and transportation.
Despite the initial alert, the tsunami swell that reached the Washington and Oregon coast and the mouth of the Columbia River was a mere 1-2 feet, as confirmed by Colby Neuman, a meteorologist with the National Weather Service. While this caused unusual currents and tides for a day, the impacts were far less severe than what would occur from a tsunami generated by a major earthquake originating closer to home, such as those from the Cascadia or Aleutian subduction zones.
Unlike the recent event, tsunamis generated by earthquakes in the Aleutian subduction zone are directly aimed at the Pacific Northwest. Even more critical is the threat from the Cascadia subduction zone, which poses an even greater danger due to its proximity and the significantly reduced warning times it would afford coastal communities for earthquake preparedness.
Experts like Eungard warn that a powerful earthquake, potentially a magnitude 9, from either the Cascadia or Aleutian subduction zones would unleash immense damage and widespread disruption. For instance, areas such as Wahkiakum’s Puget Island could see protective dikes overtopped, leaving land submerged and infrastructure devastated. The scale of such a natural disaster demands immediate and decisive action.
Given the potential for widespread communication outages following a major earthquake, officials stress that the shaking itself is the only warning residents should rely on for immediate evacuation. The modeling indicates a dangerously short window—less than 20 minutes—to reach higher ground, a period that includes the crucial four or five minutes of the earthquake’s shaking.
The response to the recent, smaller tsunami provided valuable lessons. Agencies like the National Weather Service and the U.S. Coast Guard were praised for their effective communication and information dissemination throughout the event. Lt. Cmdr. Jacqueline Hunnicutt of the U.S. Coast Guard Sector Columbia River emphasized that this incident served as an active practice, allowing responders to refine their protocols and coordination for future, more severe events.
Ultimately, this recent “wake-up call” underscores the undeniable tsunami risk facing Oregon and Washington. Experts agree that the Pacific Northwest must accelerate its comprehensive earthquake preparedness plans, as the next significant seismic event may not offer the same degree of fortune or allow for such a measured response. The time for proactive preparation is now.
