- In the Pacific Northwest,
a slow motion collision of tectonic plates
along the Cascadia subduction zone has been building tension
for over 320 years.
And when that tension is released,
the resulting earthquake is likely to be
as large as a magnitude 9.
That will be 45 times more powerful
than California's most destructive quake in 1906.
And the consequences defy imagination.
(building rumbling)
This megathrust earthquake is predicted to be so significant
locals simply call it The Big One.
And scientists estimate that it has an alarming 37% chance
of occurring within the next 50 years.
In this episode, we'll learn just how this mega quake
will impact our cities and find out what's being done
to prepare our infrastructure
and learn some invaluable lessons about how to make a plan
for when The Big One hits.
(dramatic music)
Subduction zone earthquakes often cause sudden movement
and changes on the ocean floor,
triggering tsunamis large enough to completely wipe
coastal communities off the map.
Remember the Fukushima power plant disaster?
In 2011, Japan was hit by a magnitude 9 earthquake,
similar to what we're anticipating here on the West Coast
and it unleashed a tsunami of devastating proportions.
Chris Goldfinger is a geologist in Oregon
who studies earthquakes and he happened to be in Japan
when the quake hit.
I asked him to tell me about his experience.
- We went outside and just watched
buildings moving, flagpoles whipping,
and it just felt like the whole earth had turned to liquid.
Yet you could feel this grinding plate underneath us.
And as we watched it, though,
we knew that Northeast Japan wasn't expected
to have anything bigger than about an 8.4.
But when it hit three minutes and went past three minutes,
we knew that was wrong.
They were going, this is a nine.
It has to be a nine.
That's what it takes, three minutes
- [Maiya] Because of a long history of earthquakes,
Japan was so well prepared that this mega quake destroyed
a relatively small number of buildings.
But they just didn't expect
the size of the tsunami that followed.
(tsunami siren howling)
Allison Pyrch, an engineer from Oregon,
visited in the aftermath.
- And it toppled most of their tsunami walls
inundated huge amounts of the Japan coastline.
It killed 16,000 people.
And we were there six to eight weeks after the tsunami,
going and standing there and smelling the fish smell.
And you can imagine where the water went
'cause you can see the water lines
on the trees on the hills around it.
You can see the pieces of people's lives strewn around.
So as an Oregonian, that's really hard,
knowing that that's what our coastline is gonna look like.
- And while the Tohoku quake in Japan
was the costliest natural disaster in the world's history,
here on the West Coast of the United States,
we're nowhere near as prepared as Japan was
for this kind of disaster.
- If that had been Cascadia and I'd been at work,
my building would have collapsed.
There's no question about it.
I might've gotten out, it might not, but it would be gone.
Everybody thought Cascadia was A size,
meaning no earthquakes,
because historically, that's what it was.
It was dead silent.
And then the first evidence was discovered
in the early to mid eighties,
realized that we just happened to be
sitting in a quiet spot.
- The Cascadia subduction zone is a 600 mile fault
that runs from Northern California up to British Columbia.
Over the last 10,000 years, geologic records show
that there have been 41 subduction quakes here,
which averages out to about one every 250 years.
The last one came in the year 1700.
That's 321 years ago.
Since then, tension along the subduction zone
has been slowly building
as the Juan de Fuca plate steadily pushes into
and under the North American plate.
The plate edge continues to gradually bend and buckle
and one day, it'll release that tension
causing up to five minutes of violent shaking and triggering
an immense tsunami
that could reach a hundred feet in some areas.
- If you were looking at a bird's eye view
of Portland or Seattle,
very soon after shaking started,
bridges and other longer infrastructure
are going to be warping and falling off their foundations.
You would see unreinforced masonry buildings
start to collapse.
This is where 95% of Oregon and Southwest Washington's fuel
is brought in and stored.
These tanks will deform, they'll spill.
Any type of spark or metal hitting each other
could also start a fire.
The Cascadia subduction zone earthquake is gonna be
one of the worst disasters America's ever seen.
- [Maiya] Officials in Portland, Oregon
created this animation showing what they predict
one of the busiest bridges in the Northwest will look like.
And it's not pretty.
(tense music) (earth rumbling)
In the aftermath of the quake,
survivors along the coastline and towns like Seaside, Oregon
will have as little as 20 minutes to evacuate
before the massive tsunami hits.
- In a place like Seaside, what we need to do
is get from here up to the hills right back there.
It's a very straight path, it's not that far.
It's a very doable evacuation, but there's a problem here
because there's no way to get there
without crossing one of these bridges.
The bridges were built before plate tectonics,
so we've got no retrofitting at all.
If these bridges go down,
people trying to evacuate are gonna have a problem.
They're gonna have to swim the river
and then continue evacuating up the hill.
- [Maiya] To get an idea of just how risky
this situation is, Chris actually flew our camera person
oversee Seaside in his acrobatic plane.
(engine sputters)
- As we're flying over Seaside,
we can see how low elevation the town is.
Ground doesn't really rise much
until you get well on the other side of the highway.
Pretty much everything on the west side of Highway 101
is pretty likely to be inundated.
(ominous music)
I mean, I came home from Japan feeling optimistic about it,
but at the same time, I look around at the Pacific Northwest
and I can see just visually that yeah,
we are a thousand years behind
and this is not gonna be easy to catch up.
- But officials in the Northwest are getting started.
Portland is currently reviewing options
to build a new Burnside Bridge
to serve as a lifeline after the quake.
And all new structures are being built up
to earthquake standards.
Still, the vast majority of homes in the region
are not ready for earthquakes of this magnitude,
and aren't even bolted to their foundations.
Michael Wieber is a contractor
specializing in retrofitting homes
to make them more likely to survive an earthquake.
- So this house was built in 1911.
There really wasn't a building code back down.
This house is sitting on the foundation
through the grace of gravity.
We're going to rectify that.
We're going to collect those earthquake loads
and get them into the foundation
to prevent the house from moving off the foundation.
So the vast majority of our work takes place
underneath the house.
So in this case, the basement.
(soft guitar music)
All right, so this is a special order plywood
that's designed for earthquake loads,
and it's going to install like this
to get those loads from this beam up here
into the sill plate down here.
And then we'll install this side plate
and we'll continue that load path into the foundation.
(drill whirring)
- The most important retrofit is strengthening
the connection from the walls to the floors
and to the foundation.
Some homes are simple to retrofit
and it's possible to do it yourself,
but others are very complicated,
so it's worth having a professional take a look
if you live in an earthquake-prone area.
And there's a lot you can do without construction skills,
like making sure tall furniture, heavy wall decorations,
appliances, and even electronics like televisions
are securely attached to the wall,
so they don't fall on people during a quake.
Mark Ginsburg is a Portland NET
or neighborhood emergency team leader
and has been preparing for The Big One for over a decade.
Despite living and breathing disaster preparedness,
Mark, surprisingly doesn't seem too overwhelmed
by the inevitable earthquake.
- It's not the thing that keeps me up at night
because I know that I can't control it.
I understand where I live
and I understand that that's a possible risk.
But I also know that if I do some preparedness work
and if I do trainings,
this year I redid my first aid and AED trainings.
Those are the parts that I can do and that I can control.
There's your house and the physical things,
there's the knowledge, and there's a plan.
But I think having the things that you as a family
or a household need to just be independent
for a little while is really crucial.
- Here are Mark's top five most important things
to keep in your home or garage
when preparing for The Big One.
- Shelf stable food, water, one gallon per person per day.
Good fire extinguishers, the more the merrier.
Two bucket toilet.
Toilet seat, clips on the bucket.
Toilet paper.
Saw dust for your poop.
For in one gas shutoff tool.
Thank you.
Water shutoff in the bottom, gas shutoff on top.
If you turn off your gas,
you leave it off and let the pros turn it back up.
- Shutting off your gas can be crucial to stopping fires.
If you smell gas in your home after an earthquake,
Mark suggests grabbing your for in one tool
and simply turning the valve to the off position.
It's easy to feel discouraged or overwhelmed
when thinking about preparing for a disaster
as large as The Big One,
but I think we could all take a page out of Mark's book.
- The time to figure out what to do
is not after the earthquake, the flood, the fire,
but to know in advance, if those things happen,
what should we do?
- You don't have to join a local emergency team,
although it's great if you do,
but just taking small steps today to start your preparation
like picking up a gallon of water
or a few extra cans of soup for your pantry
can go a long way.
- People will want to help
and will step up to help to the best of their abilities.
That's what everything shows will happen
and what has happened in the past
and we can expect that's what's gonna happen
should we need it in Portland.
- And for a more detailed look on how you can prepare
ahead of time for an earthquake
or for any other disaster for that matter,
check out our episode on how to stock your pantry
and pack a go-bag.
Thanks for tuning into this episode of "Weathered"
and as always, don't forget to like and subscribe
so you never miss an episode.
See you guys next time.
(soft music)