Old Klallam stories tell of a great flood, when rivers became salt, when villagers paddled to avoid treetops, and canoes were “tied to a mountaintop that broke off.” According to Jamie Valadez of the Lower Elwha, who spoke at the Port Angeles Library in May, numerous stories of a great flood have been recounted by tribal elders over the past century.
In the 1860s, a Makah leader, Billy Balch, recounted a story to James Swan who wrote it down, describing when “water flowed from Neeah bay through the Waatch prairie, and Cape Flattery was an Island. That water receded and left Neeah Bay dry for four days and became very warm. It then rose again without any swell or waves and submerged the whole of the cape and in fact the whole country except the mountains back of Clyoquote.” (Source: “THE ORPHAN TSUNAMI OF 1700” by Brian Atwater et al.)
Geologists have uncovered evidence of multiple tsunamis and earthquakes along the coastal areas of the Pacific Northwest. The most obvious clues are former marshes and forests that had been buried by mudflats and sand, which means that the ground there has sunk by a notable amount – up to one or two meters. One stark example is Wilapa Bay, north of Astoria, Oregon, where at low tide you can see the remains of a forest. These plains of long-dead trees standing in a meadow are sometimes called “ghost forests.”
Plate Tectonics and Geological Detectives
Beneath the lush greenery of the Pacific Northwest lie two converging plates – the Juan de Fuca Plate and the North American Plate. The danger to the region is posed by the fact that the two plates are pushing against each other and Juan de Fuca Plate has been subducted under the North American plate.
In the year 1700, long before Lewis and Clark explored the region, these two plates suddenly shifted, creating a massive earthquake and a tsunami that spread all the way across the Pacific to Japan. It’s probable that at least some of the oral histories passed down among the Klallam and other coastal tribes refer to this event.
Geologist Brian Atwater has been able to pinpoint the exact date of the event, even though no written records exist from that time on these shores. Instead, he found detailed documentation across the ocean in Japan. In his book, THE ORPHAN TSUNAMI OF 1700, written with a group of Japanese colleagues, Atwater recounts a drama that took place over three hundred years ago in a harbor on the east coast of Japan. There, in January of 1700, records indicate that a ship carrying 170 bales of rice was prevented repeatedly from entering the harbor. Although the weather was good, the boat encountered “weird waves,” according to Atwater, and eventually sank. Two crewmen died and all the rice was lost. This event was documented in detail because the owner of the rice demanded an investigation. Over three centuries later, these government documents provided historical clues to an event that originated thousands of miles away, in the Pacific Northwest. (For his work, Atwater was named one of Time’s “100 Most Influential People” in 2005.)
Not a Great Curly Wave
As Atwater pointed out during the Port Angeles event at the library in May, the tsunami evacuation signs posted along coastal areas are pretty but do not accurately depict what a tsunami looks like. Instead of a big curly wave, a tsunami is more like the great floods described in the Klallam stories – what Atwater called a “wave train.” A tsunami is an inundation of salt water onto land, and areas with narrow channels are at the highest risk. The salt water rises and recedes, then rises and recedes again. This cycle could continue for many hours and the first one might not necessarily be the biggest.
So what does it all mean for folks who live in the area? Unfortunately, it means it could happen again. Clallam County Emergency Management has plenty of information available on their website (http://www.clallam.net/emergencymanagement/) about how to prepare for a cataclysmic event and what to do if it happens.
A 2010 assessment, “Hazard Mitigation Plan for Clallam County,” available on the website, points out that “[a]t least half of the County is susceptible to bluff failure along the shoreline” (p.40). It states that Port Angeles “would be devastated by the occurrence of a local earthquake and/or tsunami.” It mentions a fault running through the city, the steep slopes and bluffs in town, the sections built on fill, and the potential for fires. “Several critical facilities are located along the waterfront including docks, the ferry terminal, a large medical facility, and the transit terminal. The waterfront is a ‘hot spot’ because of these multiple hazards and the fact that a significant number of large fuel tanks containing diesel, fuel oil, and propane line the waterfront.” One can only imagine what the mountains of logs down at the harbor will do to the waterfront during a tsunami.
The document also describes numerous mitigation projects at various stages of completion, mostly having to do with backup systems for power, communications and water. The website provide maps showing evacuation routes and a detailed list of supplies that residents should have ready. Critical on their list is the recommendation that each household have on hand a gallon of water per person per day, to last at least several days.