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Cascadia Report

If you live in western Oregon, you’ve most likely heard talk of the “big one,” a large upcoming earthquake. But how serious is this “big one” anyway, and what can we do to prepare? Never fear, I’m here to sort out any confusion!

Long story short, the Juan de Fuca plate off the West Coast is shoving eastward under the North American plate, pushing up the caught North American plate. Once the tension becomes too much the North American plate will suddenly slide westword over the Juan de Fuca plate. This will cause the Cascadia earthquake and tsunami. The Cascadia earthquake may be in the magnitude 8 or 9 range, which is why it’s called the “big one.”

There has been a Cascadia earthquake on average every 240 years, and the last one was over 300 years ago. While the length of time between earthquakes can be and has been much longer than 300 years, we are still considered overdue for a large earthquake. The issue is, we here in Oregon simply aren’t prepared. Over 2,000 of our bridges (and we have around 2,500 total) weren’t built with this giant earthquake in mind, and almost 1,000 will possibly collapse in the event of a Cascadia earthquake. Virtually all of our fuel is on Portland soil prone to liquefaction, a process that may also claim much of Portland Airport. 1,000 schools may be destroyed. The valley could face several months without electricity and a year without running water. The coast could face half a year without electricity and three years without running water. The tsunami following the Cascadia earthquake will be another matter entirely. And what is the risk of this happening? ⅓ in the next 50 years, with a M8 being much more likely than a M9. Clearly, Cascadia is a risk we must take seriously.

So what can be done? Beforehand, everyone can make an emergency plan with their family. What will people do, where will they go, and who will they contact in the case of an emergency? Keep in mind that internet and phone lines may be down, and plan accordingly. You and your family can choose a contact person who lives far away that they entire family can call to know who is safe as local lines may be jammed. And if you live in a tsunami zone like 22,000 Oregonians, you can make a plan for evacuating with your family. All of these plans can hold in other types of emergencies as well.

Consider adding a whistle to your keychain you can blow in the unlikely event of being buried in rubble in an earthquake. Also consider creating a personal emergency kit you can carry around in case something goes wrong. According to, a personal emergency kit should have:

- Copies of important medical documents, including information about any medication and your doctor and medical consent forms

-Copies of personal identification

-Some food and water

-First aid kit and handbook, including any medication

-Non-latex gloves and dust masks

-A whistle


-Local road maps (if you’re over 16)

- List of emergency contact numbers

-Flashlight with extra batteries and light bulbs

-Toiletries and personal care supplies, such as extra glasses

-Copies of keys

-Clothes, including shoes, and a blanket (you can buy small plastic blankets if space is an issue).

A family kit can be kept in the house in case of ny emergency, such as a snowstorm or, in this case, an earthquake. It should, according to the same website, contain:

-Water (one gallon/person/day.)

-Food (probably about 2,000 calories/person/day) (don’t forget a can opener!)

-Wrenches for turning off gas

-Working gloves and goggles

-Heavy-duty plastic bags

-Duct tape

-Battery-powered radio and flashlight


-Matches/a lighter

-Equipment for cooking outside

-Cooking utensils

-Pet supplies, including water

-Changes of clothing

-A sleeping bag or warm blankets

-Copies of important documents.

Cars can also be a storage place for extra emergency items, like water and clothing. This can be helpful in all emergencies, not only Cascadia earthquakes. To prepare for the earthquake in a mental sense, you can also become First Aid certified and learn how to turn off your house’s electricity and gas. To protect yourself from your household object, you may consider strapping large pieces of furniture to the walls and in other ways attaching smaller items to their places. That way, nothing will fall on heads during an earthquake. Perhaps you could also use flexible gas connectors instead of rigid ones.

Now, what should be done if shaking starts? It’s simple: Drop, cover, and hold on. Drop under a table, preferably, or a sturdy desk or similar piece of furniture. Cover your head and neck. Finally, hold on to whatever you can, as long as its stable. If there are no tables or desks, you can huddle against an interior wall, away from any glass, in a place where nothing nearby can fall on you. If you cannot move, still cover your head and neck as much as possible. If you’re using a wheelchair, position yourself as safely as possible and lock the legs of the wheelchair. If you’re outside, move into as open an area as possible; this is not a good time to be crushed by a tree.

After the earthquake, turn off gas and electricity, and unplug anything that’s broken. Move away from buildings in case of aftershocks. Call your emergency contact person, but make no other calls so that the lines are left open for more important business. Follow your family emergency plan. But what if you live in the tsunami zone? Then, my friend, this is not a good time to dilly-daddle. You need to get to high ground. How to tell if the earthquake was serious enough to cause a tsunami? The same website as created the lists for emergency kits says, “If the earthquake lasts 20 seconds or more of very strong shaking (which may seem like forever) and you are in a tsunami hazard zone, evacuate to a safe area as soon as you can safely walk.”

Tsunami waves can be up to 70 feet high; walk 100 feet above sea level for safety. Two miles inland works as well, although doing both can’t hurt. But be careful, you might only have 15-20 minutes before the first wave arrives, maybe less. As mentioned in the quote above, this is a time for walking, not driving. Roads might be broken and unusable. Walking is most likely a safer option.

Hopefully you will now have a better idea of the danger of the Cascadia earthquake and how to protect yourself. I hope you all stay safe in the event of an earthquake!


Jahn, E. (Producer). (2015). Unprepared [Video file]. Retrieved from

Dengler, L., Hemphill-Haley, M., Felton, V., Monro, A., & Warren, J. (2009). Living on Shaky Ground (447659). Retrieved from Portland Bureau of Emergency Management website:

Oregon Seismic Safety Policy Advisory Commission , Hemphill-Haley, M., Felton, V., Monro, A., & Warren, J. (2013, February). The Oregon Resilience Plan . Retrieved from Oregon Seismic Safety Policy Advisory Commission website:

OPB Staff. (2015, September 18). Watch OPB's Unprepared Documentary . Retrieved from OPB website:

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