LiDAR Landslide Spatial Analysis at the Little Smoky River Highway 49 Crossing Site, Alberta (NTS 83N)

Landslides within river valleys are relatively common in Alberta, notably so along rivers that have incised into glacial and Cretaceous sediments. We used a morphological approach using light detection and ranging (LiDAR), colour imagery, and displacement data to create an inventory of landslide features at the Little Smoky River Highway 49 crossing site.

We performed spatial GIS analysis on these features using LiDAR data and commercially available software. We compared the results with the available displacement information in an attempt to relate surface texture attributes to landslide activity for known geological conditions. Finally, we assessed the methodology for its potential to generate an understanding of landslide types, processes, and relative levels of activity at sites that do not have displacement information, but have similar geological conditions.

Preliminary results were comparable to field observations for the majority of landslides. However, the spatial analysis tended to overestimate activity on the west side of the river crossing, likely a result of the unique morphology with large steep backscarps. This method was intended to be an additional metric to assess landslide activity, not a replacement for more traditional approaches.