As development pressures around the country increase, so does the likelihood of building in areas susceptible to landslides. Such areas are neither isolated nor far in-between. They span the entire eastern part of US, from New England to the Appalachian region encompassing some of the most scenic areas in the east as well as large urban areas. Landslide risks loom through them all. Pittsburgh and Cincinnati are two examples of urbanized areas with frequent landslides where developments on hills and hillsides are common. In the Great Plains, heavy rains combined with loss of vegetation due to wildfires trigger landslides in clay-rich rocky areas. On the west coast, earthquakes add to the causes of landslides. For example, the 1994 Northridge earthquake triggered many thousand landslides in the Santa Susanna Mountains. In short, no region of the country is safe from landslides, whether caused by geophysical or human-made factors.
Although the term landslide is often used somewhat loosely to mean any fairly rapid movement of rocks and sediment downslope, it is actually more accurate to use the term mass wasting to refer to the wide variety of mass movement processes that wear away at the Earth's surface.