Landslides in Wyoming

A landslide is the downslope movement of a mass of rock or soil driven by gravity. Landslides, which are also known as mass movements, encompass a variety of processes, deposits, and landforms that can be broadly classified into slides, flows, falls, topples, and spreads. Examples of specific landslide types include rockfalls, debris flows, and slumps.

Landslides can damage or destroy roads, pipelines, structures, and utility lines. They can also temporarily block rivers with earthen dams, which when overtopped can cause flooding downstream. When landslides occur in populated areas, they can cause significant damage and loss of life. Rock type, slope angle, hydrology, and geologic structure are some of the major factors that determine whether an area is prone to landslides. Human activities, such as road construction and surface water diversion, can also have an impact on landslide occurrence.

Landslides occur every year in Wyoming, however, most occur in remote areas and do no typically cause damage. The WSGS has mapped more than 30,000 landslides throughout the state.