Yesterday, the Outpost was alerted to the fact that the powers that be have revised the iconic tsunami zone maps that we coast-dwellers have seared into memory.
According to Ryan Aylward, who stopped by the Outpost offices yesterday with brochures in hand, work on the revised maps began around 2020, and involved both high-detail LIDAR work and historical core samples to determine the outer boundaries of where the seas might rise when The Big One strikes.
The good news for Humboldt is that a great deal of land that was thought to be in the tsunami zone is no longer considered to be in danger. For instance: There are now places around the town of Fairhaven that can serve as safe evacuation sites, when that previously was not thought to be the case.
That’s not the case everywhere in Humboldt, but a glance at the map shows that we’ve been able to reclaim a bunch of land from the tsunami zone. A bunch of the Arcata Bottoms, for instance, is now in the safe zone — denoted in green, on the new maps — when it used to be in the dangerous “yellow zone. “
Up in Del Norte, Aylward said, the case is altered. A lot more territory is riskier than had been understood, previously.
Remember: What’s depicted on these maps are worst-case inundation scenarios, and that worst case is a major Cascadia Subduction Zone slip, which has in the past and will in the future result in earthquakes in the neighborhood of a magnitude 9. When that happens a tsunami is guaranteed, and you have minutes to get to high ground.
So you’ll want to know where safe territory is well in advance. Find below the new, revised maps, and reacquaint yourself with the status of the special places on your daily routine. If that’s not working for whatever reason, you can find a direct link here. You can also find handy printable detail maps for at-risk communities in Humboldt, Mendocino and Del Norte counties at the Redwood Coast Tsunami Work Group.