Landslide and Land Subsidence Hazards to Pipelines

Because of the long, linear nature of pipeline corridors, they often cross areas that are highly susceptible to landslides. Techniques to assess the hazard posed by the presence of landslides can be applied to these corridors provided certain minimum data requirements, such as slope and material properties, can be met within these areas. The level and sophistication of maps designed to portray landslide hazard or attributes that relate to landslide hazard vary widely. They range from maps that depict the qualitative judgment of the geologist, technician, or engineer to maps that display the percent chance (probability) of a landslide occurring in the future with respect to time, area, or both. Quantitative methods of depicting probability of landslides vary from the purely statistical correlation of various factors to physical process-based models that attempt to replicate the failure and, in some cases, the movement of slope materials. Depending on the type of landslides being considered, the type of analysis employed, and the accuracy of the data available, landslide-hazard maps are subject to considerable variation in their uncertainty. Due to the fact that datasets of the variables required for hazard assessments are often incomplete and include approximations, it is often difficult to quantify the uncertainty that exists in estimates of hazard levels.