EP – Earthquakes and Tsunami

Experiencing Cascadian Subduction Earthquake and Tsunami

When the next Cascadian subduction zone earthquake occurs off our coast, it will be seven to nine on the Richter scale. You will feel up to five minutes of such intense shaking that you will unlikely be able to stay on your feet. It will be the most frightening thing most of you will ever experience. When the earthquake subsides, the coastline will have dropped three to six feet in elevation. 

Within 10 to 15 minutes, the first tsunami will reach our beach. It will be a surge of water as high as 30 feet (a three-story building), possibly higher. Within a half-hour or less, another surge will arrive, and more after that. Some of these successive waves can be higher than the first.

If you are home at the time of this earthquake, you could be injured by broken glass, a falling roof beam, a tree falling on your house, a refrigerator or large bookcase falling over, or burned by fire from a toppled woodstove or burning firewood literally bounced out of your fireplace onto your floor.

If your home is in the tsunami hazard zone, roughly 70 feet elevation or lower, you will have to flee to higher ground as soon as the shaking eases enough for you to be able to get moving, in order to avoid the coming series of tsunamis. You should not return to your home for at least 12 hours or more to avoid subsequent tsunamis and you can expect aftershock quakes for the next few days.

We will not get to choose the time this catastrophe occurs. We know it will happen; we just don’t know when. The last one occurred in the dark of a January night. Our next one could occur at night or in daylight. It could occur during a howling sleet storm with 60 mph winds in the middle of the night. It could occur during freezing weather, with temperatures in the teens. It could occur during a sunny community 4th of July barbecue. 

If you are at home in the tsunami zone, you may have to spend 12 hours or more away from your house, so you will need a “Grab & Go” bag to take with you. The contents of a Grab & Go bag will be covered in section I. This will be helpful even if you find refuge with a neighbor. It is essential if you are spending the 12 hours in the woods in inclement weather.

It is essential that you understand that after the quake, there will be no electricity, piped- in water, cell or landline phone service, The only possible communications will be by GMRS hand held radios (line of sight only), subscription satellite phones and ham radios. All roads out of our community will be blocked by fallen trees, power poles, collapsed bridges and landslides.

If You Are at Home

You can expect the following hazards if you are at home during the coming earthquake:

  • Falling masonry (fireplaces, chimneys, retaining walls, stem walls—especially stone, brick or concrete block)
  • Falling center beams
  • Broken glass (windows, light fixtures, dishes, framed pictures, mirrors, etc.)
  • Falling furniture (refrigerators, tall bookcases, sideboards, armoires (some of these can be prevented from falling by fastening them securely to the wall)
  • Falling trees (less likely)
  • Falling utility poles
  • Landslides
  • Fire caused by a toppling woodstove or burning material bouncing out of your fireplace

If your home is in the tsunami zone

If your home is in the tsunami zone, leave immediately for higher ground and your designated assembly area. Take your Grab & Go bag with you.

  1. Help the injured (as much as you can without endangering yourself) to higher ground. Remember, this scenario may be happening in a storm and/or at night. 
  2. Be prepared to spend at least 12 hours or more away from your home. Successive waves can come for several hours and some can be larger than the first one. Seek shelter with a high-ground neighbor, if available, or be prepared to find or make shelter on the nearby high ground. Your Grab & Go bag is essential to carry you through this harrowing time.
  3. Expect significant aftershocks over the next few days.

If your home is above the tsunami zone

If your home is above the tsunami zone (above 70 feet elevation), keep an eye out for an especially high wave which could reach your elevation and be ready to go higher yet with your Grab & Go bag.

  1. Don shoes to protect against broken glass.
  2. Aid people pinned under fallen beams, furniture, etc. in your own house. Free them carefully.
  3. Extinguish any fires started by burning materials shaken out of fireplaces or woodstoves.
  4. Give first aid to injured householders.
  5. Go to your neighborhood assembly area and be prepared to help and give first aid to neighbors and others fleeing the tsunami zone.
  6. Assess the damage to your home. Is it still a place where you can safely shelter? If not, evacuate to a neighbor’s house. Otherwise, secure your house against weather and stabilize structures. 

If you are in your vehicle

If you are traveling anywhere in your car during the quake, watch out for falling buildings, utility poles, and trees; landslides; collapsed bridges, tunnels and overpasses. If in a tsunami zone, head for higher ground. You may have to take your Grab & Go bag and leave your car to do so. 

If you are not in danger from a tsunami, head for shelter but watch out for damaged buildings that may collapse in after-shocks. Decide if you are close enough to home to walk there. Decide ahead of time where you would go if the quake hit during any of several points on your journey. Be thinking ahead. Always have a Grab & Go bag in your vehicle.

If you are on foot

Most areas you could be hiking are close to high ground. Watch for landslides and falling trees.

If you are hiking the beach out on Bayocean Spit, you should try to reach the big hill on the spit. You’ll have 10-15 minutes to get up that hill. Carry in a small knapsack (or in your pockets) a space blanket, water, energy bars, and fire-making materials.  Be prepared to spend up to 12 hours on the hill while waiting for the series of tsunamis to subside. You may have to stay longer if the spit is breached at the south end.

Maintaining until outside help arrives

Maintaining until outside helps arrives: Remember Hurricane Katrina in 2005? Don’t expect outside help for at least two weeks, and it may be much longer. Portland, Salem, Eugene, Vancouver, Olympia, Tacoma, Seattle—all will be devastated. Many people in those cities will be killed by the quake and thousands will be injured. Rescuers will go there first. If you want to last until help does come, you should be thinking about keeping safe.

At the Cape Meares community level, we can form mutual aid plans before the quake occurs. For example, we now have supply sheds in three neighborhoods containing emergency and medical supplies We can make a list of generator owners and some people have specialized skills, such as construction, plumbing, medicine, carpentry, hunting, fishing, and wild foraging in which they may offer to instruct others. Holding emergency preparedness seminars for community members, on a regular basis, is helpful.

In New Orleans, after Hurricane Katrina, the people who fared the best were those who relied on themselves first, then worked cooperatively with their neighbors. People who waited for “the government” to help them fared poorly.

  1. Be prepared to share your house with some people. Be prepared for the fact that some people may come to you who are injured, in shock, disoriented, or hysterical. Guide them to the closest assembly area, where they may get more help.
  2. After your house is stabilized, make it weather-tight with the tools and materials you have stockpiled in anticipation of this emergency. This could include covering holes in your roof, covering broken windows and jacking up and supporting portions of your house.
  3. Take steps to maintain your body heat. Have plenty of clothing and blankets. Inspect your woodstove or fireplace for damage to stove pipes and flue liners. You may still be able to use these. But be aware of the danger of fire or carbon monoxide.
  4. Assess your water supply. Store as much as you have room for. Rotate annually. Rainwater harvesting is very helpful. Water can be hauled from creeks and purified by filtering, boiling or chemicals (e.g., bleach: 1/8 tsp per gallon).
  5. Determine if the waste line from your house to your septic tank is still intact. If so, you can still use the toilets in your house by pouring water in to flush them. If the line is broken, repair it using the pipe you have stockpiled for this purpose. After the earthquake in Christchurch, New Zealand in 2011, sewer systems failed but many septic systems remained useable in the rural areas.
  6. If your septic system has been destroyed, be prepared to bury human waste and possibly build an outhouse. Take care that this is not near a stream.
  7. Shut off power at the breaker panel against the day when power will be restored.
  8. Shut off your large propane tank until you’re sure your system is not leaking.
  9. Be prepared to help rescue and care for injured and sick neighbors. Get your Red Cross training updated.  Especially useful will be the Red Cross Wilderness and Remote first-aid course as well as CERT training.
  10. Be prepared to help recover and bury the dead. Make sure the burials are clearly marked and identified for subsequent removal by authorities.
  11. Be prepared for the remote possibility of looters or roving gangs of thugs from outside the community who come to take advantage of the disaster.
  12. We live in an area rich in natural resources. You can prepare yourself by learning to get food from fish, game and wild plants.

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