When I lived in Oregon, I was just 80 miles from the tsunami capital of the United States — Crescent City, California. More than 30 tsunamis have struck this small coastal community in Northern California since 1933. The most memorable being in 1964, following the 9.2 magnitude Good Friday Earthquake in Anchorage, Alaska.
Visiting Crescent City numerous times while growing up, I remember there is a round asphalt slab upon which a 25-ton replica tetrapod — a shoreline armoring device — was meant to rest. Because of the tsunami, however, the giant structure is located to the side of the pad, moved by the powerful waves that swept through the town.
The city has left it there as a reminder of how destructive the ocean can be.
The Pacific Northwest is seismologically active thanks to numerous faults that run throughout the region. None more dangerous than the Cascadia subduction zone. It’s a dragon laying in wait to awaken violently when we’re least expecting.
When the earth gives in to the pressure it’s been under since the last quake in 1700, the result is likely to be a magnitude 9, or higher, event. A 9 on the Ricter scale is approximately 158-times bigger than the 6.8 magnitude Nisqually earthquake in 2001.
The Darrington-Devil’s Mountain fault that runs south of Lopez Island has the possibility of being as strong as the Nisqually quake.
Both of these locations have the potential to cause a significant tsunami in our county. While much of our community is higher than where a 10-foot tsunami could reach, there are parts that remain within the danger zone. Eastsound and Lopez Village both have parts of the community that will likely be inundated by a tsunami when one comes.
When you feel the shake of a quake, that is your signal to head for the hills — literally. Do not go toward the water to watch the wave. Do not attempt to move your boat into deeper water, as the current will be moving at a dangerous speed. Getting away from the shoreline is a surefire way to avoid tsunami-caused fatalities.
San Juan County Department of Emergency Management has a detailed website at http://joomla.sanjuandem.net/, wherein it outlines emergency preparation procedures each household in our county should follow in the event of an earthquake and tsunami.