Partners preparing for the Big One

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Earthquake expert Michael Olsen (right), associate professor of geomatics in the School of Civil and Construction Engineering and co-principal investigator of O-HELP discusses the Big One with landslide expert Ben Leshchinsky, assistant professor of geotechnical engineering in the College of Forestry and the School of Civil and Construction Engineering.

Description

How can we prepare most effectively for the Cascadia Subduction Zone earthquake? An interactive website called O-HELP, developed by Oregon State researchers, zooms in to any point in Oregon and displays the various risks, giving planning agencies, utilities, and individuals a head start.

Season number
Season 4
Episode number
5
Transcript

TRANSCRIPT

­­[MUSIC: I Keep Waiting for Earthquakes, by Lucky Dragons, used with permission under a Creative Commons Attribution NonCommercial Share-Alike License]

STEVE FRANDZEL: Hmm, that’s creepy. But I’ve been kind of obsessing about by earthquakes lately. When I start­ed working on this podcast, just for kicks I watched some footage from the 1974 movie, Earthquake, starring Charlton Heston, Ava Gardner, and George Kennedy. It’s  about a monster quake that flattens Los Angeles. Yeah, that’s it in the background.

[EARTHQUAKE SOUNDS: from the movie "Earthquake"]

When the earthquake hits, the shaking lasts for almost seven minutes. I thought, that’s got to be an exaggeration, right? Well, not so much. During a real mega quake, severe, uninterrupted shaking can last longer than five minutes. The magnitude 9.1 that hit Japan on March 11, 2011, rocked Tokyo for six full minutes. And even after the ground stopped shaking, tall buildings continued to sway for another 12 to 15 minutes. It produced a devastating tsunami and the Fukushima nuclear disaster. And it was caused by the same type of geologic formation that will trigger our own Big One, the Cascadia subduction zone earthquake.

[DRAMATIC DRUM STABS: Used with permission under a Creative Commons License]

Simulations predict that the Oregon coast will experience severe and violent shaking, while cities along the I-5 corridor will experience very strong shaking. Either way, it doesn’t sound too good.

MICHAEL OLSEN: Basically, when we think in terms of plate tectonics, we’ve got big land masses, the different continents are structured on, or even pieces of the continents are structured on, that are moving and intersecting with one another. Here in Oregon we’ve got part where we’ve got basically one plate that is subducting underneath another plate. And so it’s moving offshore, moving underneath, and that’s what causes our beautiful coast mountain range as well as the Cascades is that uplift from the movement of mass underneath.

FRANDZEL: That’s Michael Olsen, an associate professor of geomatics in the School of Civil and Construction Engineering and an expert in earthquake engineering and hazard mitigation.

OLSEN: The result of that is you have that potential for earthquakes, and very strong earthquakes. A subduction zone earthquake like the Cascadia subduction zone tend to be larger, longer and more powerful than maybe the shallow crustal earthquakes that you see down in areas like California.

FRANDZEL: In the Pacific Northwest, especially west of the Cascade mountains, the prospect of the Big One, a magnitude 9.0-plus earthquake, is a pervasive, nagging presence. It’s like someone sneaking around and tapping you on the shoulder every so often just to let you know he’s there.

[MUSIC: Hot Swing, by Kevin MacLeod, used with permission under a Creative Commons Attribution License]

On average, large Cascadia quakes have struck every 500 to 600 years, but the intervals can be 100 to 300 years, and the last one occurred in January of 1700. We know it’s coming. Could be tomorrow, might not happen for 30 years. But it’s coming. The question is, what are we going to do about it?

In this episode, we’ll take a look at a remarkable and practical tool that planners can use to prepare for the day that the earth will definitely not stand still.  

[MUSIC: The Ether Bunny, by Eyes Closed Audio, used with permission under a Creative Commons Attribution license.]

NARRATOR: From the College of Engineering at Oregon State University, this is Engineering Out Loud.

FRANDZEL: The forces unleashed by a magnitude 9 earthquake are impossible to wrap your head around, they’re almost meaningless. It’s the energy equivalent of 32 billion tons of TNT, a hundred Mt. St. Helens eruptions. What do you do with that information except nod and say, OK, wow?

BACKGROUND VOICE: Whoa, that’s a lot.

FRANDZEL: Considered from a detached, scientific perspective, it’s fascinating stuff. But in real terms – in human terms – it’s terrifying. People will lose their lives. Devastation will be widespread.

[DRAMATIC CYMBALS: Used with permission under a Creative Commons License]

It’s scary, but just worrying gets you nothing, except maybe insomnia. This is a time for action, and today’s podcast is about an important contribution by Oregon State researchers to help us face the danger.

[MUSIC: Lightfeet, by Podington Bear, used with permission under a Creative Commons Attribution NonCommercial International License]

It’s called the Oregon Hazard Explorer for Lifelines Program, or O-HELP. Michael is one of its co-creators. O-HELP emerged from a partnership initiated buy Oregon State, called the Cascadia Lifelines Program, or CLIP. We’ll come back to that after looking at why O-HELP is such a remarkable and valuable source of information. O-HELP is an innovative, interactive – and I have to say – engaging. It graphically displays detailed earthquake and tsunami risks for any spot in Oregon.

OLSEN: O-HELP is a platform that we have developed to help engineers understand hazards, particularly in the context of the state of Oregon and the Cascadia subduction zone. So it really helps them look at not only the level of ground shaking we’d anticipate, but a lot of derivative hazards that happen as well, like liquefaction and landslides, so they ultimately can consider these processes early in their planning design to come up with a better design from the start.

FRANDZEL: We’re also joined by Ben Leshchinsky, assistant professor of geotechnical engineering. He has a joint appointment in the College of Forestry and the School of Civil and Construction Engineering. Ben’s an authority on landslides, which are certain to occur after a big earthquake, and he’s also working on O-HELP.

BEN LESHCHINSKY: Usually when we’re doing design of structures or infrastructure, a big starting point is looking at hazards and what sort of hazards might affect your design in the end. But it’s kind of difficult to say, well what would the influence be in certain locations? O-HELP is intended as a tool to provide people with insight with site specific impacts of that event occurring.

FRANDZEL: Though O-HELP is designed for engineers, planners, geologists, and others helping the state prepare for a big earthquake, anyone can use it. Navigating the site is easy, and the color-coded results are presented in such a way that even a layman can interpret their fundamental meaning and imagine the impact for any given location. Not to make light of the Cascadia earthquake, but O-HELP is fun to play around with in a geeky kind of way.

[MUSIC: Lightfeet, by Podington Bear, used with permission under a Creative Commons Attribution NonCommercial International License]

You can zoom in to a region, county, city, or a very specific location, like where you live or work, or where you’re sitting at this moment. Then you can choose various earthquake hazards, like the most obvious: ground shaking, which is technically called ground acceleration. It’s the motion recorded on a seismograph. You can check the risk and predicted extent of landslides and tsunami inundation zones – that’s how far the water will reach inland – and the possibility of liquefaction, which has got to be one of the most bizarre effects of an earthquake, when what used to be solid ground starts acting like a liquid. I highly recommend checking out the website and experimenting, just messing around with it.

Michael described a real-world scenario where O-HELP could be used.

OLSEN: So the first would be if an engineer is given a project where they need to develop a site. So it would be one of the first places that that engineer would go to collect information about the site. They would be able to pull in different data layers and identify which are the predominant hazards that they need to be thinking about in the design. Another way that the tool could be used is also from the infrastructure management side of things, where somebody has a highway that they’re interested in and they want to know where some of the most critical points along the highway that are going to be damaged as a result of the earthquake. And so that helps them kind of prioritize their repair efforts and decide where’s the best spot to be putting the money, because you can’t just harden up the whole entire line. There’s not an infinite supply of resources. But this helps them focus in on which are the areas that need the most significant help.

LESHCHINSKY: We had an engineer just this past month out of Portland developing a project asking about relative liquefaction and landslide hazard for a site they’re developing for some critical infrastructure. So they contacted us regarding the O-HELP report and what it said, and they were pretty satisfied that a tool like this was available for their preliminary site investigation.

FRANDZEL: They both make it clear that O-HELP is intended for preliminary guidance, not a final verdict.

LESHCHINSKY: They’re not necessarily going to stop with O-HELP and say  this is the risk. But it helps guide an engineer who is often overworked, tired, working on lots of projects, kind of recognize what those relative hazards might be, and then do some more specific engineering based on the site conditions, whether it’s water or the topography. But they would do some more specific analyses after O-HELP, but O-HELP guides them.

OLSEN: Yeah, and at the end of the day, too, I think it’s important to make the disclaimer that this tool is not meant to say this is a site that you can’t build on or you shouldn’t build on. It’s kind of to start that conversation, but then be followed up with more detailed analyses. Another thing that is really important in these types of maps is to continually update the maps and improve them, continue to make them better with time. So really it’s that concept of living maps rather than a paper based map.

LESHCHINSKY: O-HELP is a living breathing tool, so it’s always changing and we’re always adding data.

[MUSIC: Lightfeet, by Podington Bear, used with permission under a Creative Commons Attribution NonCommercial International License]

FRANDZEL: And O-HELP wins high marks from the professionals who have used it. In fact, people from other states, like Washington, have inquired if something similar might be coming their way, but right now the focus is on Oregon.

OLSEN: Most of our feedback has been through the CLIP members who have been very satisfied with our tool and looking at different ways to promote it within their organizations. We see a constant, steady stream of people using it.

FRANDZEL: That steady stream of visitors began as a torrent. Though O-HELP went online in 2015, it didn’t draw much attention beyond CLIP members. But when Oregon State officially launched the website on June 1, 2016, that changed overnight.

OLSEN: Unfortunately, on the first day of its release, we had about 15,000 people accessing it within a 24-hour period.

FRANDZEL: The server crashed. But things calmed down after the initial surge. Now the site attracts 100 to 200 visitors a week, many of them new, and users tend to spend a lot of time there. 

OLSEN: I think it’s a mix of engineers using it as well as people in the general public, people looking, hey I want to buy a home in this area have also found it to be a useful tool, even though that’s not necessarily the intended application.

[MUSIC: Lode Runner, by Podington Bear, used with permission under a Creative Commons Attribution NonCommercial International License]

FRANDZEL: As I mentioned O-HELP was made possible by the Cascadia Lifelines Program, or CLIP, a nine-member consortium coordinated by the School of Civil and Construction Engineering in 2013. Its members build and maintain the infrastructure and services that we don’t think about much until they’re gone. Roads, bridges, electricity and gas, water and sewers. Its primary members are the Oregon Department of Transportation, Northwest Natural Gas, Portland General Electric, Bonneville Power Administration, and the Port of Portland. Several water bureaus and the Pacific Earthquake Engineering Research Center round out the group.

OLSEN: They can pool their resources together so that they can kind  of help tackle bigger problems. And the other thing is getting these agencies to talk with one another because the power goes out or the water goes out, that affects everybody else. If a bridge goes down, that affects people responding to repair a power line or other aspects like that, so it’s really a way to kind of look at the multiple pieces that are necessary in disaster recovery.

FRANDZEL: Much of the data used to build the website was compiled through yet another partnership, this one between Oregon State and the Oregon Department of Geology and Mineral Industries, or DOGAMI.

OLSEN: They kind of have the role of learning about the hazards in the state and communicating that information, so they do a lot of hazard mapping. They put together a lot of spatial data to describe what the impacts would be as a result of a Cascadia subduction zone event, and they created a lot of data layers. But these layers weren’t really readily accessible to the public. They still required use of geographic information systems, which required kind of a unique, special skill set. So we came up with the idea of using a web GIS, web geographic information systems platform, to really help get it so people could use the data without necessarily being experts in the geospatial side of things and understand and have licenses for those software.

FRANDZEL: Naturally, a lot of people besides engineers and planners want to know what a big earthquake might do to their homes.

OLSEN: With time, people have started to come to understand that these hazards are there, these threats are there, and starting to think about those in decisions like buying property, building a home. Those kind of things are kind of on the forefront of people’s minds.

LESHCHINSKY: There’s quite a bit of talk about the Cascadia subduction zone event in the news and in the media, and people are concerned. So here they have an opportunity to plug in their address and see what the relative hazard is to them.

FRANDZEL: Which is exactly what I did, and I brought the report with me to get an expert assessment. This is my house.  

OLSEN: We’re live, right? [Laughter]

FRANDZEL: Yeah, yeah. There are four sections. There’s location, there’s general site information, then there’s seismic hazards, and ground deformation hazard rating. So, what can you tell me looking at this report about where I live?

LESHCHINSKY: Well, with regards to the ground deformation hazard ratings, you come in very low. There’s a low probability of landslides, or liquefaction for that matter, which probably implies you live on relatively flat ground. Is that the case?

FRANDZEL: It’s a top of a hill that sloped slightly but it’s not steep.

LESHCHINSKY: Right. We expect a lot of liquefaction hazard near rivers, sandy areas, places that are saturated and not necessarily the top of hills. Landslide hazards of course occur at hills or sloping areas. But if you have some distance or clearance, likely your hazard is lowered.

FRANDZEL: Michael, anything?

OLSEN: A couple of things to consider there is on the actual ground deformation, it looks like an area where that’s not very probable to occur. There will be strong ground shaking, but the reality of that is pretty much anywhere here in the valley, especially the Corvallis area, you would be expecting about 20 percent of the force of gravity in your acceleration there. Wood structures tend to do pretty well, unreinforced masonry unfortunately doesn’t. So it depends on what your house is built on how much of a concern that would be. Definitely would wake you up in the night. Like I said it’s roughly about 20 percent of the force of gravity, which is enough that can cause structural damage.

FRANDZEL: So I’m looking pretty good, If I’m home.

OLSEN: Yeah.

 

LESHCHINSKY: But with that said, it’s always wise to be prepared, have a disaster kit and just be ready. There’s nothing to lose by doing that.

FRANDZEL: OK, so my house is made of wood, which is good, but it’s also in the Willamette Valley – not so good, at least when you’re talking about earthquakes. The soft sediment deposited by the Willamette River over eons made the valley floor rich and bountiful farmland. But it also amplifies seismic waves way more than bedrock does, and that means more shaking. And it’s also more prone to liquefaction, a phenomenon where the ground becomes saturated by water and starts behaving like a liquid, like quicksand. Even on very mild slopes, the liquefied ground can deform and flow, while structures built on top of it sink or tilt at crazy angles.

[MUSIC: Surprising Power, by Art of Escapism, used with permission under a Creative Commons Attribution NonCommercial International License]

LESHCHINSKY: What happens is the ground starts shaking, and that water is trapped between the grains, and what happens is since that water is trapped, water pressure builds up, and essentially those grains become buoyant and they float. So all of the strength that you might have had by putting your foundation or your structure on that sand is gone. You’re building on a liquid. One might relate to going to the beach where you’re going in the area where the waves are crashing. You might notice that when you bring your foot off the ground, that sand all of a sudden becomes liquid. That is essentially liquefaction, except it happens on a much larger scale. However it’s not essentially an immediate impact during the earthquake. I think the main threat during an earthquake is something catastrophic like a landslide or building collapse. Landslides can happen rapidly and don’t necessarily give people the opportunity to escape. Liquefaction and lateral spreading, which is ground movements from liquefaction, that gives people time to escape, but it can completely compromise water systems, power, and foundations.

FRANDZEL: Predictably, realtors and home buyers are turning to O-HELP to look at these risk factors to evaluate property.

OLSEN: I’ve heard of some realtors that have kind of been looking into it and using it. It’s more, I think actually the people buying the home that have kind of been looking at it rather than the realtors. I don’t know how many of the realtors want to necessarily bring up these points. Unfortunately.

LESHCHINSKY: No hazards here. [Laughter]

OLSEN: Yeah.

FRANDZEL: Despite all the dark scenarios, Michael offered some reassurance.  

OLSEN: It’s very easy to get caught up in the doom and gloom when you’re talking about these hazards and these different types of events. But I think the good news is, as we understand these hazards a lot better than we have in the past, and especially as the public becomes more and more aware of these hazards, it gives us the capability to prepare. And it may seem daunting, there’s only so many resources we can put at this, but every little bit that we kind of put towards it and prepare, we’re that much closer to being better off, so it makes a big difference.

[MUSIC: Night at the Dance Hall, by Twin Musicom, used with permission under a Creative Commons Attribution License]

FRANDZEL: This episode was produced and hosted by me, Steve Frandzel, with additional audio editing by Brian Blythe. O-HELP was conceived a few years ago by Dan Gillins, Michael’s colleague in the geomatics lab and who now works at the National Oceanic and Atmospheric Administration. The graduate students on the O-HELP team are Rubini Mahalingram, Mahyar Sharifi-Mood, Farid Javadnejad, and Nicholas Mathews. I hope I got those right.  

Our intro music is The Ether Bunny, by Eyes Closed Audio on SoundCloud and used with permission of a Creative Commons Attribution License. Other music and effects in this episode were also used with appropriate licenses. You can find the links on our website. For more episodes, visit engineeringoutloud.oregonstate.edu, or subscribe by searching Engineering Out Loud on your favorite podcast app.

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