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Make Every School Quake-Safe

Not far from the Cannon Beach City Hall shown in "Deadliest Earthquakes," on quiet Beaver Street just steps from Ecola Creek, is Cannon Beach Elementary, a grade school with 110 students. I often think about the children who attend that school as I work to reduce tsunami hazards on the Pacific Northwest coast.

Cannon Beach Elementary, like three other schools in the Seaside school district, lies smack in the tsunami inundation zone. No one recognized the danger when the school was built. If the Cascadia Fault ruptures during school hours, nine teachers will have to get those 110 children to duck under their desks, cover their heads, and hold on to table legs until the shaking stops. Hopefully the school itself will stand up through the shaking; one of its two wood-framed buildings is highly collapse-prone.

After the shaking, frightened children and stressed teachers may not be able to reach the nearest high ground for safety, because the bridge they would normally use to cross the nearby creek is considered likely to collapse. Instead, the teachers may have to lead their students across Ecola Creek on foot or else walk a half-mile through the shaken town to the Tsunami Evacuation Building (if it is built) or even farther to a designated evacuation site in the hills. If everything goes just right, teachers and children will reach safety just minutes before the tsunami strikes.

I think of those students (and their families) to remind myself what it means to live along the Cascadia fault. Cannon Beach Elementary is typical of many coastal schools in the tsunami zone, built long before scientists had deciphered the risk from Cascadia earthquakes.

There are plenty of discoveries to be made in earthquake science. Predicting earthquakes and tsunamis, the Holy Grail of seismology, attracts top talent to that field. Stay tuned; breakthroughs are sure to come. Fortunately, designing and building safer structures to withstand the deadliest earthquakes is no mystery. Using what we know can save lives and protect property right now.

I was excited to be part of the team that developed the conceptual design for a Tsunami Evacuation Building that would replace the current City Hall in Cannon Beach, Oregon. That building will feature reinforced concrete columns with lots of open space to allow water to flow through, a deep robust foundation anchored extra-deep in the ground to handle scouring by waves, steel cables under tension to help the structure resist and recover from swaying, and wide stairs to a sturdy rooftop patio. These are methods common in the engineering of bridges, skyscrapers, and other structures designed to flex and move, but they are not commonly combined in structures close to sea level.

Architect Jay Raskin, former Mayor of Cannon Beach and co-leader of the TEB effort, says, "As we increasingly understand the risks of the Cascadia earthquake and tsunami, we must apply that knowledge to protect our residents and visitors. The new City Hall/TEB will provide a safe haven for those unable to reach high ground in time and will help the City lead relief and recovery efforts following the disaster."

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Danger On The Beach

In NOVA's Deadliest Earthquakes, thanks to digital special effects, I stand on a beautiful Oregon beach as a tsunami looms and surges toward me. Of course I would not survive that encounter, and I hope never to experience it!

But tens of thousands of people (on a good summer day) could be on Pacific Northwest beaches at the moment the Cascadia Fault ruptures, unleashing a tsunami that could sweep ashore in as few as 15-20 minutes. If you are one of them, what should you do?

First, you should wait for the shaking to stop. An earthquake could last for as little as a few seconds to as long as several minutes. No matter the duration or apparent strength of the shaking, if you are on a beach or anywhere within the tsunami inundation zone you should get yourself and your loved ones to safe ground by moving inland and uphill.

So as soon as the shaking stops, get off the beach and move to safe ground as quickly and as directly as possible following any available designated evacuation routes. Bluffs and dunes don't count, and neither do beachside houses or motels. The only safe ground is outside the tsunami zone, until the risk has passed.

It's possible for tsunamis generated far from our shores to strike the Pacific Northwest. This risk is likely to be announced hours before impact by sirens and other warning systems. But any time water recedes from the shore in an unusual manner, even without earthquake shaking, leave the beach and seek safe ground.

More Pacific Northwest coast towns should consider Tsunami Evacuation Buildings like the one envisioned for Cannon Beach, Oregon. Such buildings could offer a safe refuge for many coastal residents and visitors. But until that day, no visitor to our spectacular coast should spend a day by the waves without taking note of high ground and the shortest way to get there.

Publicist's note: Yumei Wang is featured in NOVA's Deadliest Earthquakes, premiering Tuesday, January 11th at 8 PM ET/PT on most PBS stations. Please check your local listings.

Yumei Wang

Yumei Wang leads the Geohazards team at the Oregon Department of Geology and Mineral Industries, where her work focuses on lowering risks from earthquakes, tsunamis, and landslides. She has taken part in post-disaster damage assessments from the Chile, China, and Sumatra earthquakes. Her current priorities include statewide earthquake risk assessment, the design of North America’s first tsunami shelter, and efforts to implement innovative policies to manage earthquake risks, including Oregon’s unique seismic retrofit grant program. Wang has an MS in Civil Engineering from the University of California, Berkeley and a BA in Geological Sciences from the University of California, Santa Barbara. She is a featured expert in NOVA's Deadliest Earthquakes.

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