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Shaken and Stirred: Northwest Earthquake and Tsunami

Washington 9.0 earthquake--Are you ready? Oregon 9.0 Earthquake--Are you ready?Suddenly the Pacific Northwest is on the national stage for its earthquake and tsunami vulnerability, thanks to a New Yorker article. “The Really Big One,” by Kathryn Schulz, has triggered attention from dozens of local papers and news sites. Yet even before the New Yorker shook the Northwest (pun intended), Oregon Public Broadcasting had been featuring Hart Crowser engineer Allison Pyrch in its “Unprepared” series, to alert the region to the impending disaster in hopes that we will get prepared.

Also, Allison recently gave a presentation for the Lake Oswego Sustainability Network: “Surviving a 9.0, Lessons Learned from Japan and Beyond.” If you are involved in emergency management or just plain interested in massive disasters and their aftermaths, settle in for some powerful visuals and easy-to-follow explanations about earthquakes in Japan and Chile, how the 9.0 earthquake and tsunami will happen in the Pacific Northwest, and what you can to do to be resilient.

Watch the whole “Surviving a 9.0” video to get unusual insight into what’s ahead, or if you’re pressed for time, skip to one of these minute points:

  • 9:00 Jan Castle introduces Allison Pyrch 10:56 Allison Pyrch’s presentation begins with how the Pacific Northwest 9.0 earthquake will happen
  • 14:25 Comparing the Japan and Chile quakes “It didn’t stop shaking for a day”
  • 21:45 Fire damage/natural gas 22:30 Water, wastewater, and electrical systems; liquid fuel; natural gas
  • 24:25 Lifelines/infrastructure/airports “PDX will not be up and running”
  • 28:35 Port damage/economics
  • 31:45 How prepared is the Pacific Northwest? When will it happen? “We are 9 ½ months pregnant”
  • 35:00 What will it look like?
  • 37:32 What you can do
  • 40:30 What businesses can do
  • 42:11 Can you be sustainable without being resilient?
  • 43:33 What about a resiliency rating system similar to LEED?
  • 53:30 Will utilities, transportation, hospitals be useable after the 9.0? “We’re toast”
  • 1:01:30 End of Allison’s presentation; additional information from Jan Castle on how to prepare
  • 1:19:19 How sustainability measures in your home lead to resiliency

Oregon Public Broadcasting’s Resiliency Blitz Starts January 26

Allison Pyrch of Hart Crowser

Allison Pyrch at a base isolated hospital near Ishinomaki, Japan, talking to Ed Jahn, OPB Producer. With Jay Wilson, Clackamas County Emergency Manager (left) and the hospital engineer. Listen January 26-28 on OPB radio’s Morning Edition between 7 and 9 am and at www.OPBnews.org.

For the last year, Allison Pyrch, a geotechnical engineer with Hart Crowser in Portland, Oregon has been the American Society of Civil Engineers representative to support Oregon Public Broadcasting in the preparation of a 2015 “media blitz” highlighting Oregon’s dire need for improved seismic resiliency.

Allison, the section secretary and a member of the ASCE Technical Committee on Lifeline Earthquake Engineering, travelled to Japan with the OPB Field Guide crew in September to highlight the damage and engineering successes that were observed after the 2011 subduction zone earthquake and tsunami.

The Japan footage, as well as footage from within Oregon, will be used throughout the year to bring awareness to the need for seismic resiliency here at home. The work will culminate with an hour-long documentary in October 2015.

The first segment of coverage will air January 26-28 on OPB radio’s morning Edition between 7 and 9 am can be found now on the OPB website here and here. The series will discuss critical structures in tsunami zones. The January 28th segment will feature Allison and cover how Japan constructs base isolated hospitals that are ready for business immediately after a major seismic event. Tune in and listen!

Geotechnical Lessons from the Tohoku Earthquake

Japan landslide area

Rockslide (background) and flood protection (foreground) in Ishinomaki City, Japan (Photo: Dave Swanson, Reid Middleton)

The magnitude 7.3 earthquake that struck Japan six days ago is a reminder of the more devastating magnitude 9.0 earthquake that struck March 11, 2011. In an earlier post we mentioned a reconnaissance team that traveled to Miyagi Prefecture in Japan in May 2011 after the earthquake and tsunami.

In the landslide area photo above from 2011, the light colored rock slope failed even with reinforcement that protected the slope to the left. The entire land area settled, which allowed Tsunami and high tide water access to the shoreline. Fortunately, in this area the Tsunami water was not as high as other areas, so the buildings weren’t washed away. Blue tarp temporarily protects the river bank from overtopping at high tide.

Doug Lindquist of Hart Crowser had these observations about the geotechnical damage:
Damage generally happened in known geologic hazard areas (tsunami zones, areas near past landslides, liquefiable areas, and reclaimed land).
• Liquefaction damage was extensive even 150 kilometers away from the fault rupture. (Seattle is about 100 kilometers from the Cascadia Subduction Zone.)
• Ground improvement measures are effective.
• Engineering methods can reasonably estimate the liquefaction hazard.
• Newer structures performed well when designed considering known geologic hazards.

As the reconnaissance team report reminds us, a similar earthquake will happen along the Cascadia Subduction Zone, off the coastline from northern California to British Columbia. The impacts of this event on our communities and industry will depend on the actions we take now to prepare for it. The lessons learned from Japan can be applied in our own communities.

For more details on the reconnaissance team’s findings, along with some fascinating photographs, see the report here.