As part of the Geohazard Risk Management Program (GRMP), Klohn Crippen Berger (KCB) was commissioned by Alberta Transportation (AT) to conduct a call-out inspection of a deep-seated landslide site on Hwy 570, west of Dorothy, Alberta. During the inspection, Unmanned Aerial Vehicle (UAV) photos and videos revealed a potential rockfall hazard to the traffic on Hwy 570.

KCB conducted a geotechnical investigation that involved collecting historical air photos and past LiDAR data and conducted two UAV surveys to assess the historical activity of the landslide. The UAV surveys were used to complete photogrammetry reconstruction of the ground surface and perform a change detection analysis with point cloud data and LiDAR data. Zones of material loss and accumulation were identified within a 0.4 m level of detection.

After the initial assessment, KCB assisted AT with the procurement of contractor services from BAT Construction Ltd. and Spidex All Terrain Excavating Inc. for scaling and disposal of the rock blocks that posed the potential rockfall hazard. In addition, KCB completed the environmental overview assessment and site surveys to assess wildlife and vegetation at the site. The environmental assessment aimed to limit liability from the potential spread of regulated and invasive weeds and the destruction of protected plants or wildlife while removing the rockfall hazard.