Cascadia: The Earthquake that will Destroy Westcoast America

My step mother’s father was a geologist who was a member of one of the teams that put together the risk analysis for a potential Cascadia subduction zone quake. The historical record uncovered and the implications for present day danger were so alarming that he not only left the Pacific Northwest, he moved to Europe and never came back.

I love how Simon covered this with the enthusiasm of someone who clearly doesn't live in the Pacific Northwest

My dad is Alaskan and survived the 1964 quake, but lost several friends. He moved to Europe when he was 20 and this was partially motivated by that earthquake he and his family barely survived.

One thing everyone forgets in the scenario, is Mt. Rainier. At the very minimum, you will have avalanches coming at you at frightening speeds. If you have deep shaking, it could affect the volcano itself.

Not gonna lie, I was fully expecting this to be 2020's final boss

As someone who digs subway tunnels in Los Angeles for a living, this is concerning to say the least.

I attended a training session about disaster preparedness held near Everett, WA about 20 years ago. One of the local USGS geologists was a presenter. He said we need to have our emergency preps stored well away from buildings and buried (with lid access) to protect them from earthquake damage so we could actually retrieve them when we need them. He said we will need them and our buildings/homes aren't likely to be standing to get our preps from inside. He said our go bags needed to be kept next to the door we will be exiting through. Very chilling to listen to how he, personally, was preparing for such a recently discovered threat. I have been prepping since Mt. St. Helen's blew, myself, so the concept of prepping wasn't new to me. It pretty much was to everyone else there. I live about 15 miles EAST of I-5 and avoid WEST of it like the plague.

I currently live in this Cascadia zone. It’s scary how many people don’t take this possibility seriously. I plan to move inland soon and can’t wait as this has been a huge source of anxiety and nightmares for me.

One element of my job is to ensure corporate data survivability by backing up data at redundant, geographically seperated data centers. While inspecting one San Francisco firm, we discovered they had no redundant data backup. When I enquired, the VP rolled his eyes at me and said " Ive heard [earthquake] predictions all my life, but other than a small tremor here and there, there hasnt been ANYTHING to worry about!" This is the problem. People have no frame of reference. They think it wont happen because it hasnt yet happened to THEM.

Seattleite here. You missed two things: 1) We DO get earthquakes on a somewhat regular basis that can wake us up or shatter the odd window. 2) A 9.2 will have enough force to loosen the glaciers on Mt Rainier, if not awaken it or one of its brethren. Don't worry, it's worse than you think.

1982, my ship pulled into a harbor on Talcauno, Chile. The harbor bottom was about 50 feet deep. NOW, THERE IS NO HARBOR AND THAT AREA IS NOW NEAR SEA LEVEL.

My dad was in college in Oregon when the new cascadia research was being done in the 80s. When it was my turn to go to college in Vancouver BC, moving into those new glass high-rise apartments he said, “You really don’t want to be living here during an earthquake. The whole PNW is almost 100 years overdue for a Big One.” He meant like a 1964 earthquake where we grew up, and personally got a taste of in 2018.

Chilean here, I just wanted to say that we are lucky to have earthquakes so often (like with 15~20 years of difference), because that way we are forced to have better quality of buildings and houses, most of old houses in Chile can't survive the quakes, so the ones that are standing right now have been proved by the circumstances.

In the early 80s I stayed with someone who had a ranch that the San Andreas fault ran through. Some people showed up from (as I recall) a university. They placed measuring devices into the fault line, then quit for lunch. When they returned they tried to remove one of the devices and they could not get it out of the ground. In about 90 minutes the plate had moved enough to trap some of their equipment. I saw that with my own eyes. They were pretty stimulated about the amount of movement in that short time. The ranch owner is dead and now I’m old, but I sure remember that. It took place in December 1981.

Has anyone else been binge watching these videos? I’ve been stuck watching/listening to them every day for hours on end, mainly listening to them at work. So addicting.

I live in eastern WA, and when traveling near the coast, I have seen stands of dead trees in certain areas. The trees in these "ghost forests" were analyzed in the 80s and 90s, and they drowned circa 1700, victims of the tsunami. There is a video on youtube made by Central Washington University about these tsunamis, and on the video it says that these tsunamis occur about every 500 years on average.

I lived in Anchorage when was 7 years old and the 1964 Good Friday earthquake hit. Although there were no earthquake meters at the time, I've seen estimates of it being anywhere between a 9.2 t0 9.5 earthquake. It was terrifying. To this day, I (and anyone else I've met who lived through it) cannot speak of it without crying. I was in Seattle during the 6.8 Nisqually earthquake in 2001. It was nothing compared to the Good Friday earthquake. At 6.8, the Nisqually earthquake made the ground feel like a gentle rolling wave with the sound of thunder coming from underground. It lasted for less than one minute. The Good Friday earthquake made the ground shift violently back and forth with so much force that everyone standing outside fell to the ground, only to stand back up and then be hurled to the ground in another few seconds. It lasted for 4.5 minutes, but felt like it went on forever. My brother said he was watching the trees, sway so much that the tops of the trees would touch the ground, stand back upright, and then sway in the opposite direction and touch the ground again; over and over. I don't remember sounds besides people screaming and houses sounding like they were pulling apart. As a young girl scout, I remember our troop was on a guided walk in a State forest. The forester pointed out that the trail we were walking was directly over the fault of the Good Friday earthquake. She pointed out a tree that had grown directly over the fault line. The tree, still upright, had been ripped in half with one half located about 15 ft. from the other half. To this day, the memory of that sight is still mind-bending. I recognize the photo of downtown Anchorage shown in the video. My father went into town a few days after the quake and took a movie of Anchorage's streets. We watched those films regularly. My dad was an air force pilot and flew over Valdez on a reconnaissance mission. From the air, he took a movie of the port, the wrecked docks, the large ships sitting atop crushed homes, and washed out roads. We watched that movie regularly, too. As an adult in Seattle, I discovered that my neighbor had lived in a community near Valdez that was not as affected by the tsunami. All of her friends in Valdez perished. Many years later, my mother told us that my father always slept with his boots on for the next year or so after the earthquake. Now living in the Seattle area, I have always made my housing choices based on staying out of tsunami range and knowing the geology of the area I live in (to minimize impacts from earth movement). I do enjoy going out to the coast now and then but must admit a certain nervousness until I get back to safer ground.

Simon: "The next mega quake is 70 years overdue." 2020: Sits quitely in the corner taking notes.

growing up in Mexico city all my life and living thru countless earthquakes, I can guarantee you that this documentary is 100% accurate . great work