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Mon July 26, 2021 – West Edition # 16
Idaho. government

The database includes attributes to maintain the locations of MSE retaining walls and risk factors to assess the condition of the wall, as well as attributes for rockfall risk, so that ITD districts can assess the areas. issues that could lead to road closures.


The database includes attributes to maintain the locations of MSE retaining walls and risk factors to assess the condition of the wall, as well as attributes for rockfall risk, so that ITD districts can assess the areas. issues that could lead to road closures.
The project was sponsored by the ITD Highways Division - Construction and Materials team and funded by the ITD Research Program.

The Idaho Geological Survey (IGS) helps the Idaho Department of Transportation (ITD) learn more about landslides in Gem State. A new statewide landslide and rockfall hazard inventory database released by the IGS in late June will help ITD, emergency managers and planners to forecast and mitigate risk by identifying problematic hot spots.

The project was sponsored by the ITD Highways Division – Construction and Materials team and funded by the ITD Research Program.

The inventory contains more than 2,400 landslide entries ranging from prehistoric events to active events. It is published on the IGS website and can be accessed through an interactive web map service.

The information has also been added to ITD’s ArcGIS Online IPLAN platform. The database includes attributes to maintain the locations of MSE retaining walls and risk factors to assess the condition of the wall, as well as attributes for rockfall risk, so that ITD districts can assess the areas. issues that could lead to road closures.

The data was compiled from historical records, information provided by ITD geotechnical staff and district geologists, unpublished IGS field observations, LiDAR image analyzes, remote sensing, Newly mapped satellite and landslide images.

“The study represents a live catalog of mass movements across the state with a particular focus on transport corridors and urban areas,” said Claudio Berti, state geologist and director of the IGS. “The database is a tool for documenting and assessing slope stability risks. It is not intended to predict future events, but to document known events and show large patterns of occurrence.”

This new database replaces the last inventory published in 1991, a static map that is no longer suitable for modern digital analyzes. The 2021 version will be kept updated as new events occur or new information becomes available.

Landslide problem areas in Idaho include: Bonners Ferry, Clearwater River Basin, Horseshoe Bend, Boise Foothills, Hagerman, US 95 between Pollock and Lucile, and US 26 between Swan Valley and the Wyoming border. The geological characteristics of the bedrock, fractures, systems, precipitation, regional hydrogeology, vegetation, forest fires and the inclination of the slopes of the hills are all factors contributing to the initiation and development of landslides. ground.

For more information, visit https://apps.itd.idaho.gov/apps/research/Completed/RP278.pdf.