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Since 1995, Oregon has been in sync with Japan and other countries that must deal with tsunamis.   Although details vary, tsunami mitigation strategies, led by Japan, commonly are based on sensible land use planning.  That is, critical facilities and schools are discouraged or prohibited in tsunami inundation zones.  For a country that has over a thousand years of history with this issue, Japan has evolved its strategy through tragic experience.

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2011 Tohoku tsunami.  Kyodo/AP

In 2012, following the complete failure of engineered tsunami defenses in the 2011 M9 earthquake and tsunami, the Japanese Diet (their legislative body) passed a new national law creating more strict land use zones for future tsunami.  The failures of 2011 were largely due to underestimation of the tsunami size expected, which in turn had it’s links to outdated seismological theories.   One of the lessons of the 2011 earthquake and tsunami was that we are still learning and making large errors.   Given that plate tectonics, our theory of everything in Earth Sciences, was only accepted around ~ 1964, this should be expected.   Given that harsh lesson, Japan chose to strengthen their land use policy,  and not allow critical facilities, or schools to be built in tsunami inundation zones.  This action in part is based on the realization of the very large uncertainties that remain in the forecasting of the size and occurrence of great subduction earthquakes and tsunami.  When in doubt, Japan chose a conservative path that focuses on public safety.

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Cartoon illustrating major elements of Japan’s updated 2012 land use policy.  Strusińska-Correia, 2017, International Journal of Risk Reduction.  

With the relatively recent discovery of the Cascadia M9 earthquake and tsunami issue, Oregon was the first coastal State to implement a tsunami mitigation strategy.  SB 379 was passed in 1995 and, much like Japan, restricted certain critical facilities from being constructed in the tsunami inundation zone.   Although tsunami modeling by DOGAMI was fairly crude,  it was a step in the direction of resiliency.  In 2013, new comprehensive tsunami inundation maps were created for the State by DOGAMI.  The new maps were based on an intensive effort to integrate all the geologic and geophysical data to arrive at a scientifically defensible set of source earthquakes and tsunami scenarios that could pass peer review scrutiny.  And they did.  This put Oregon in the forefront of coastal states, and countries for that matter, none of which had such products.  

Undoing the Progress:  Step 1

But after such a good start in Oregon, things began to go sideways.   Although the new tsunami models and maps were created by the State’s own geologic science agency, DOGAMI,  the Oregon legislature failed to adopt the new tsunami studies into law.   The new tsunami inundation lines extended further inland than the old one, and there was pushback.

Step 2

Not long after that, in 2015, OSU was given a large donation to build a new marine science building in Newport.  The Oregon legislature matched the donation with $20M to build a “Demonstration Project”, that is, a demonstration of how to build a school in a tsunami zone.  It then became clear why the legislature ignored the new tsunami studies.   Members of the Coastal Caucus pushed a plan to promote development in tsunami zones, and to begin to remove perceived obstacles.   One obstacle to development was and is that essential services, police, fire, medical and schools would be needed.  If you can’t build those, ultimately, development would be inhibited.  So the OSU building was a demonstration of how development could proceed in tsunami zones.  This was done in spite of having safer, better and cheaper sites nearby, and ultimately will put OSU students and staff at risk.   In addition, the “demonstration” does not take into account the increased cost of building in a tsunami zone, which is likely to be cost prohibitive in most relevant cases.  https://atquake.wordpress.com/2019/06/27/huh/

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OSU marine science building under construction on the sandbar in Newport.

Step 3

What then would the next step be?  That became apparent last year when a bill (HB 3309) sponsored by Rep. David Gomberg was floated to repeal the original SB 379 tsunami line.  This was done under the radar, so that there was no significant public discussion, and many representatives voted for it thinking it was a minor tweak to mining regulations.  It was that, but it also targeted removal of Oregon’s sensible land use policy.  The Bill was signed by Governor Brown, who congratulated Senate President Peter Courtney by letter, while at the same time telling members of the press that she was disappointed by the bill she just signed into law.

Step 4

In parallel with these steps, the American Society of Civil Engineers (ASCE) were preparing their next periodic update to the Building Codes.  Normally these are coordinated with the International Building Code (IBC) and routinely adopted by individual states.  This time though, the ASCE decided to embark on a new and unfamiliar area, tsunami mitigation.  They produced some structural guidelines on tsunami loads, debris impact loads, and scouring by tsunami waves that are quite useful for structures that are built in tsunami inundation zones.  But here is where things went wrong.   What sort of structures would you build in a tsunami zone exactly, and why?   The new codes apply to Risk Class 3 and 4, essential facilities.  Without getting deep into the weeds, this is mainly high-occupancy structures, and critical services such as police, fire, hospitals and primary and secondary schools.   Well, what’s wrong with that?  Standards, those are good, aren’t they?  Well, not always.  The creation of a standard for building in a tsunami zone is a clear departure from what most countries see as best practice.  It undermines the practice of avoidance of tsunami inundation zones, proven to be the only effective defense.  There are exceptions of course, and vertical evacuation facilities for areas with no good options are obvious ones.  The ASCE deals with those explicitly, and this is good, but the codes can also be applied to  other critical facilities as well, or for that matter, virtually anything else in the inundation zone.   This leaves many ambiguities and a loophole a truck could drive through.

To compound what I consider to be an major error in implying building key facilities in a tsunami zone would be acceptable, The ASCE introduced more problems.  To apply the ASCE codes to a specific site, you need inundation depth from the tsunami and velocity to do the calculations.  None of the five western states involved (Alaska, Oregon, California and Hawaii) have such data, so the ASCE did their own modeling to provide it.  Tsunami modeling involves much more than just running a model.  It requires input of the earthquake sources, how the faults move, how often and how much.  Oregon had done such models and published them in 2013.  But they didn’t provide the flow depth and velocities the engineers need.   In creating their own, ASCE failed to work with Earth scientists to produce high-quality models consistent with all the data available for Cascadia.  Instead, they unfortunately created inferior products with haphazard results.  Doubling down on these errors, the ASCE ignored the criticisms of external reviewers, and built these low quality models into the ACE 7-16 code updates, and then worked hard to lobby the western coastal states to adopt them.  They were not peer reviewed, or published, and criticisms were brushed aside.  Some of the states adopted the code updates that had these models embedded, but Oregon Building Codes wisely decided not to adopt the tsunami chapter due to the lack of acceptance of the modeling by the science community, and that leads us to Step 5.

Step 5

Normally, State agencies that have technical Public Safety responsibilities are rarely attacked by the legislature, but this was to be an exception.  With the rejection of the ASCE tsunami updates,  the pro-development Coastal Caucus had been derailed.  Rather than working with scientists and engineers to craft a sensible policy,  Mr. Gomberg wrote a new Bill, HB 4119 to take the authority away from Building Codes, and insert the ASCE tsunami codes, bad models and all, into law.  This would subvert the independent authority of Building Codes, and give it directly to the Legislature.  But why would the Coastal Caucus want to do this?  After all, there has never been any restriction to building developments in the tsunami zone, only critical facilities were limited, and even those were unfettered by any legal requirements since that the 1995 tsunami line was gone.   The last impediment, as perceived by the coast legislators, and publicly stated, was that to create such developments, they needed essential facilities to make them viable.  Schools, police, fire and medical, were needed to support development, and inserting the ASCE tsunami codes into law provides a way to do that.  Sort of.   The ASCE codes of course don’t directly recommend building in tsunami zones, they simply provide a blueprint for it.  Rep. Gomberg and supporters believe that this blueprint will enable development, but that’s not likely the case.   Why not?

A Dose of Reality

If HB 4119 passes the Senate, and it is signed into law, what will that mean?   The ASCE codes rely on the dubious models created to define wave heights, velocities and inundation lines.  An “essential facility” must be able to retains its essential service capability to be viable under the code requirements, and that is where the breakdown occurs.  Let’s say you want to build a new hospital to support development in South Beach, across the Bay from Newport.  For simplicity, let’s say this hypothetical Hospital is at the site of the new OSU Marine Science Center (where the variables and calculations are well known).  To survive an M9 earthquake and tsunami at this site, you’d have to go far beyond the capabilities of the new science building.  This structure is not constructed to preserve any science or other function other than refuge as a vertical evacuation structure for life-safety.  The site requires surviving the earthquake, liquefaction, the 27′ tsunami impact at roughly 30 mph, as well as potential “debris” impact, such as the NOAA ships docked next door.   Under intense pressure, OSU built the facility to do just that (it wasn’t required).  But as a hospital, to preserve its function through the disaster, it would have to do all that, and also have all its medical functions survive as well.  This means that these functions would have to be above the top of the current structure, because below that everything will be submerged.  So, starting with a base at roughly 50′ tall, the hospital would then have to be constructed above that.  Can it be done?  Sure, but the cost would be astronomical.  What about a fire station?  To retain its essential service in a tsunami zone, you would have to either put the engines on the roof, or store them in a waterproof, earthquake, liquefaction and tsunami proof structure at ground level.  Again, it could be done, but at ridiculous cost.  And when you rolled the doors open, your engines couldn’t go anywhere because of all the debris, so such a facility would be functionally useless. The same would be true for a Police facility.

 

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Destruction after the March 11, 2011 earthquake and tsunami in Japan. Photo: UNEP

Where will this go? 

The new bill (HB 4119) will likely pass and be signed, as the deck has been stacked.   Hopefully though, common sense will prevail and sensible coastal communities will simply choose not to expand and develop extensively in tsunami zones.  The opposition by scientists, emergency managers and preparedness experts, and many others has helped highlight that all that is required is a bit of common sense to not put future residents at risk from the coming great earthquake and tsunami.  Statewide policy, crafted by the scientists, engineers, and coastal communities working together for solutions, and backed up by a legislature looking out for public safety would be best.  In the absence of that, we’re left with a Darwinian condition where common sense at the local level is the only thing coastal communities have left, and for now, it will have to do.  I hope it works.

Written by eqgold

February 24, 2020 at 9:29 pm

Posted in Uncategorized

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