Proactive Landslide Risk Management Using Regional Lidar Change Detection

The occurrence or reactivation and acceleration of landslides can occur unannounced and can result in significant impacts to life, property, or the environment. The processes of slope deformation and progressive failure are more active than many realize; rapid slope failures are often preceded by years of erosion, deformation, and smaller failures. In the last 10 years, the use of lidar-derived elevation models has supported the identification of landslides across large regions and is increasing the ability of geoprofessionals to identify precursory signs of failures. During the same time period, advanced computational techniques to numerically compare multiple bare-earth lidar point cloud datasets, known as lidar change detection (LCD), coupled with the development of automated workflows, have resulted in the ability to conduct LCD rapidly across large areas. This paper demonstrates how regional LCD can provide a more complete understanding of landslide hazards and better management of risk. The paper also presents preliminary tests of applying image segmentation techniques to support LCD analysis.