Yann Gavillot | Lidar landslides and faults in Jefferson and Deer Lodge Counties, Montana

• MBMG has been working on a geohazards database of active faults, earthquakes and landslides.
• Work has largely followed where Lidar is available, which is currently limited, but progress is being made.
• Where Lidar is present, it is leveraged for locating unidentified active faults and landslides, and helps focus site specific hazards studies
• Mapping using Lidar is used to complete grant-funded geohazards studies (USGS,NEHRP, FEMA-MTDES).
• Lidar makes it easier to identify features that can even be difficult to observe on the ground, and of course allows you to cover a lot of ground quickly.
• Mapping using Lidar is essential to be able to characterize hazardous faults and landslides and produce hazards maps.
• Review of hazardous faults and landslides in Jefferson County (311 landslides) and Deer Lodge County (583+ landslides) symbolized by age & activity.
• New faults were identified using Lidar.
• The longer the fault, the more hazardous it can become.
• Any faults larger than 7km should be in the seismic registry for potential earthquake hazards.
• Some of these are present in NW Montana and the Bitterroots, but more Lidar coverage is needed.
• Slope maps can be created from hillshades and can be used to identify rockslides and rock falls.
• Preview of MT Quaternary Fault & Landslide Databases–Online Map Viewer
• Shows all features that have been confirmed with the Lidar.
• Shows locations of features as well as more detailed attribute table information.

DISCUSSION

Sackung vs. landslides–Questionable landslides were not included in the Landslide inventory/database.

Fault geometry–There is limited information about fault geometry at depth. MBMG is focusing on fault and geological mapping, and structural cross sections to constrain fault geometry and whether these are low- or high-angle faults. More mapping is needed. The geometry of course affects the hazard (low-angle faults have more seismogenic width at depth, which would equate to more earthquake hazard potential).

Confidence values–Boundary confidence for faults and landslides are assigned based on mapping certainty and geomorphic signatures. Fieldwork and detailed geological mapping are needed to identify old landslides that do not exhibit activity during the Quaternary and are not well resolved in the Lidar. Lidar mapping is better geared at resolving young and dormant landslides that are potentially more hazardous.

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John Sanford | Geohazards Database

• MBMG is building an extensive hazards database with faults, earthquakes, and landslides.
• Users can download data, create elevation profiles of landslides and view statistics, and visualize correlations between faults and earthquake activity (which might identify dormant structures).
• How best to communicate this to the public?
• As the database matures, the statistics and analyses will also mature.
• Hazard classifications in the database were based on national standard USGS practices. The youngest features are typically the most concerning, so quaternary features are the focus.

DISCUSSION

Data export–It was mentioned that there is a desire to export xy data for elevation profiles from the database.

National datasets–Info from the geohazards database is plugged into USGS national datasets. These will be going into the update of the national seismic hazard model. The next update is planned for 2023

Creating the database dashboard–The database interface is using standard ArcGIS Online tools to create the dashboard–not custom script.

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Yann Gavillot | Earthquake hazards study of the Bitterroot fault, Western Montana

• The Bitterroot fault is a high priority research area since it’s a long and active fault (~100km) within a highly populated area. The hazard and risk are high. Lidar mapping provides the first documentation of fault scarps which justified multiple site-specific studies.
• Research is ongoing in this area
• Currently dating glacial moraines cut by the fault to estimate the slip rates
• Two paleoseismic trenches were dug to constrain earthquake recurrence associated with earthquake surface ruptures. More trenches are planned this summer.
• Working on more mapping, coring lake beds, & paleoclimate reconstruction

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Mike Stickney | Earthquakes and Seismic Hazards in Montana

• History of earthquakes in Montana–most occur within the belt of seismicity.
• 1920s Three Forks (6.6)–lots of building damage
• 1935 Helena (6.3)–Felt earthquakes for days afterwards
• 4 people died from falling building debris. Temporary classrooms were set up in train cars. A tent city was erected for earthquake refugees. Even the State Armory (for emergency relief) collapsed.
• 1959 Hebgen Lake (7.3)–The largest earthquake in Montana
• There were four 6M aftershocks.
• The earthquake left a 21ft high fault scarp and triggered the massive Madison landslide. Displacement along the fault tipped the entire lake basin. This created waves that caused flooding.
• The Hebgen Dam was damaged, but it survived.
• 2005 Dillon earthquake
• Mostly minor damage–chimney damage, ground cracking
• 2017 Lincoln earthquake
• Minor ground cracking
• In summary, building codes matter.
• There is a need for more adequate seismic coverage
• They’re using the Raspberry shake network and MBMG just purchased more to add tothis network. They’re looking for host sites for this equipment.

DISCUSSION

Hosting raspberry shakes–Raspberry shakes cost about $500. Montana DOT was interested in putting them in some of their gatehouses, though noise will likely be an issue there.

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Hillary Martens | 2017 Lincoln earthquake mainshock–aftershock sequence

• The Lincoln earthquake (5.8M) was the largest event in 60 years, felt 800km away.
• UM reestablished a seismic network in Montana (2017-2022). This is complimentary to the regional seismic network run by MBMG.
• Using this network, they were able to map the aftershock sequence. There were thousands of aftershocks within the first few months of the mainshock (110 days).
• Their goal was to identify the mode and mechanism of the fault structure. It was unclear from main shock alone.
• Two years of aftershock monitoring was conducted. They initially expected this to create a right-lateral EW fault, but as more data was collected it was identified as a left-lateral NS fault plane. This is almost perpendicular to the structural fault plane. Stress was being accommodated by bookshelf faulting. This is right-lateral shear that produces multiple faults rupturing perpendicular to the shear (left-lateral).
• There was some variability in the fault orientation, but this is likely due to pre-existing weaknesses in the rock.
• In summary, the mainshock likely ruptured on a north trending LL-strike slip fault, oblique to the LCL.

DISCUSSION

Faults & seismicity–There is a complicated relationship between faults and seismicity. Quaternary faults may not be tied to the earthquake, but tertiary faults may be. However, we generally think of quaternary faults as being higher risks.

Fault type and evaluating hazard risk–Are strike-slip faults just harder to see than normal faults? Maybe it’s a deformation zone with smaller faults and not just large obvious faults. This is important to consider for evaluating seismic hazards in the future.

Andrew Long | Grants and Hazard Mitigation Projects

• Grant programs offered
• Building Resilient Infrastructures & Communities
• Hazard Mitigation Grant Program
• National Earthquake Hazard Reduction Program (Non-disaster)
• Haven’t done physical mitigation projects since 2014. More recently they’ve been focusing on:
• Retrofits (pre-destruction mitigation)
• Mapping
• Seismic hazards and liquefaction susceptibility
• Non-structural mitigations
• Bracing & strapping down items to provide stability and security to items in a building.
• Scoping using Lidar.
• Over a million in funding from various grant programs!

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Troy Blandford | Montana State Library–Lidar

• Lidar acquisition
• Granite & Ravalli counties this year (expected release summer 2022), Flathead next year.
• 88% of Montana counties are complete, in progress or planned. They’re expected to complete the state in 2024/2025.
• Partners are key for funding! They have a cost share program to leverage the USGS 3D Elevation program.
• They have the MT Elevation Working Group, which includes federal, state, county, local and private participants.
• Montana Lidar Inventory through the Montana State Library
• Building footprints derived from Lidar may be useful for analyses
• Relative elevation models–mapping river migration (Very cool visuals).

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Sean McGowan | Montana Earthquake Mitigation: Where to Start

• Flooding has been a large focus of FEMA, and there’s generally a lack of attention to earthquakes, but there’s actually more earthquake risk than flood risk (50% higher year after year).
• As population increases in MT, the earthquake risk gets higher.
• FEMA can help fund seismic mitigation plans & developing inventories
• Example from Utah
• Unreinforced masonry is a high issue in MT (and Utah).
• Held a summit with experts and created a Risk Reduction Strategy which included policy recommendations.
• They formed an Applied Technology Council and conducted an inventory of K-12 schools with minimal money and lots of volunteers.
• They found many schools not to be earthquake safe. The media exploded, and suddenly they received 171 million from the legislature.

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Scott Helm | MDOT: Who they are and what they do

• MDOT is responsible for 13,000 miles in the state with diverse geology and topography
• They aren’t just responding to disasters, but are also responsible for the design
• Responsible for identifying geohazards
• Public safety is key, but so is the impact to the system.
• They’re required to create a benefit-cost analysis.
• MDOT has lots of technical tools (such as E-resistivity, drones) and catalogues lots of borings. They rely greatly on information from other agencies.
• MDOT has a rockfall asset management program. They looked at all rockfall slopes near highways and are thinking about doing the same for highway related landslides. Funding opportunities are likely available there.
• They conduct their own research–particularly on rockfall and liquefaction analysis.
• They also pay attention to less glamorous hazards. Ex–asbestos
• Tip for grant funding: Resilience is a buzzword right now, for both communities and infrastructure.
• Next May–Shallow Exploration Drillers Conference. Hosted in Butte

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Michele Lemieux | DNRC Earthquake Response Procedure

• They test their ERP annually as well as when they get a small earthquake.
• For this test, they are notified by the USGS. They immediately get on zoom and roles are assigned.
• Adobe connect meeting room is used to communicate with leadership.
• This was found to be more effective than email.
• They’ve learned that leadership prefer visuals (like GIS maps) rather than tables.
• GIS
  • They upload relevant info into ArcGIS online. This works great during work hours, but the GIS has been problematic outside of work hours.
  • DNRC needs the GIS to be automated for anything that might need a post-earthquake perspective. Then they can work on doing the inspections and communicate with leadership. GIS is the sticking point.

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Jeff Blend | MT DEQ–Energy

• Montana Energy Office
• Covers energy emergencies which can include electricity, natural gas and liquid fuels infrastructure.
• Other emergencies include a shortage of energy availability or a rapid rise of cost that imposes a threat to the health and safety of those who are most in need.
• An energy emergency could come from another state, and one here could impact other states.
• Outages could come from sabotage, cyber hacks, or international incidents.
• Transmission is the higher risk issue than the energy plants themselves.
• Earthquake issues
  • Pipeline breaks for natural gas and petroleum.
• Call to action: Hope to work with others to map pipelines with earthquake hazards

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Anna Lang Ofstad | Creating a Resilient Montana

• Most important thing–remember why we do this and the people who are impacted.
• Zylient, Inc conducts post-earthquake reconnaissance.
• They use AI and computer vision to conduct inventories on buildings.
• Recommendations
• We can use other states as templates and use what works and makes sense for Montana.
• Start a chapter with the Earthquake Engineering Research Institute (EERI)

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Dave Lageson| Montana State University–Geohazard near Bozeman

• Significant fractures were observed at Jumbo Mountain
• The fractures were filled with rubble, but are likely quite deep.
• Lots of potential for sudden failure due to earthquakes.
• Could create a landslide dam on upper Hell Roaring Creek and dam the Gallatin River.
• Climate change is exacerbating hazard risk factors - fire, soil erosion, mass wasting.
• The high alpine is especially susceptible and should receive more attention.
• Call to action: Study the high Alpine! There are long distance effects on communities downstream.

DISCUSSION–Lightening Talks

GIS and data–GIS and data sharing is key. All hazards have effects that impact one another, but ultimately, it’s about lives.

BCA and retrofitting–Benefit Cost Analysis is hard to do for earthquakes. FEMA is trying to reform it. You have to prove that over the lifetime of the project it will save money, or not doing it would cost more. For now, the best first steps are to identify issues and notify building owners and have continued communication with building owners. Let them know how long it will take to rebuild from an earthquake if they don’t retrofit. Host voluntary workshops for builder, with the goal that these ultimately become mandatory. Identify building owners who are willing to do the retrofits and can be showcased. Get the media to cover it. This will require some grassroots work.

How not to do outreach–Portland tried putting up plaques to say a building isn’t earthquake safe. It backfired. Meanwhile in California it’s illegal to doing building assessments for hazards.

Building community education–Some communities have a parapet ordinance which required that they be braced (very inexpensive). However, in one experience a building official didn’t know what a parapet was. Education is greatly needed.

Funding–FEMA can help cover home retrofits. There are the 5% projects. There are opportunities for dual purpose funding.

Building code–If you buy a building, shouldn’t you have to bring it up to earthquake code? Is historic preservation holding things back?

Centralized data–There should be centralized data for boring data for soils. Homebuilders should have access to this information. There’s a lot of info available through MDOT, but it’s all highway related. Utah Geological Survey is using data preservation funds to digitize Geotech logs and develop a subsurface 3D database for hazard mapping. (https://geology.utah.gov/apps/borehole/)–Ben Erickson. And here’s a place to start for vs30 data–USGS arcgis.com web viewer (ask Seth Wittke for link).

Some potential future steps:

• Bring community members in early to get them on board
• The key is to identify what the communities “pain points” are. You’re always going to find a champion somewhere.
• Start with schools and government buildings–these are easier to get on board.
• There isn’t really an inventory of Montana schools for earthquakes. The most effective tactic for funding has been to share concerns with parents who then speak up.
• Include the insurance community in the conversation.
• Work with the historic preservation community. Historic Preservation grants are available that can be used for retrofits.
• Conduct public education! Huge public education opportunity even for “ugly” retrofits.

• There’s important info to be gleaned from other state commissions. We should be looking at these and think about what would and would not work in Montana. This applies to any other relevant information as well. Don’t reinvent the wheel!
• It’s obvious that we need a plan (for both scientific purposes and emergency services) in the event of an earthquake. We cannot and should not do this alone. This requires working together.
• We need to get the legislature on our side for this effort. State recognition is key. Maybe a good approach is conducting an inventory of the K-12 schools which will hopefully get parents interested. Another potential approach is using HAZUS models to simulate earthquake impacts including casualties and economic impact. Here’s why the science matters in this place. Showing the vast consequences so that folks have something on that list that resonates with them and gets them to care.
• We need to get the groups the legislatures will listen to, which may not be the state agencies, or at least not the state agencies alone.
• Communicating with the public is incredibly important and scientists or engineers may not be the right ones for the job. We may need to hire a separate entity dedicated to communication.
• A good next step might be attending a Utah Seismic Safety Commission meeting. The next one is July 7th in Salt Lake City.
• Geohazards Advisory Committee
• Multi-stakeholder
  • Research group
  • Insurance
  • Army Corps
  • This group
  • Local emergency managers (need their buy-in)
• Need for a shared database
• Buildings, pipelines, highway related landslides, coring → can they be made public?
• Get an inventory of unreinforced masonry buildings → schools → BRIC for collaboration.
• We need to setup a virtual earthquake clearinghouse plan/emergency response → communications → with strong connections between agencies prior to events.
• Work on public response on earthquake hazards → Shakeout, publications.
• Geohazards Advisory Committee – we should have one!
• How to get funding from the legislature? Right now, groups are working on small projects, and we need money to do more.
• What is the best way to structure this committee? Review others as examples.
• Look for the examples for gaps/successes from earthquake response in the last 5 years.
• In recent Puerto Rico earthquake, they were short on seismic inspectors.
• Use small grants as launchpad to demonstrate what can be done with a little money, to help make the argument for more funding.
• Identify a pilot community.
• There’s a housing crisis in many communities.
• Helena–where leadership lives.
• Think about earthquake insurance! With Firewise, if mitigation work has been done, you get a discount. Could we do the same for retrofits for earthquakes?
• MBMG could be one arm of this committee, but we need others. The agencies in attendance are willing to move forward with forming this committee.
• This will be a long process. But we’ve got to start somewhere!
• Next steps
• Draft a Mission Statement Agreement – MBMG will start the process.
• DES is meeting with FEMA in 2 weeks – there will be some state directors.
• Automate the GIS earthquake response.
• Legislative attention – pilot project needed to elevate geohazards.
• Database sharing – breaking down barriers between data and agencies.
• HAZUS model test on a specific area – Recreate 1935 Helena quake impacts.
• FEMA training – can use hours as match for a grant.
• Rapid Visual Screening for non-MBMG folks to refine info before model simulation.
• Could engineering students at Tech do this, maybe partnering with certified engineers?
• We could do this with students instead of the shakeout
• DNRC planning grants – hire consultant to do this work (since we’re all so busy).
• These grants are now for “crucial state needs”, and thus have a broader scope than they used to.
• Review other state’s examples.
• Create a communication space outside of these meetings.