Material alteration through weathering and other physio-chemical reactions. Changes in direct water content and pore pressure and in structure. The hazards associated with landslides are as diverse as the types of failure. Falls may damage roads ro buildings at the base of a steep slope, injure climbers, or remain on a road as a hazard to drivers. Slumps usually damage utilities within or below the slide mass, but seldom cause a threat to life.
Translational slides can be the most catastrophic of all.
In addition to presenting a local hazard to structures and utilities, they can cause damage and death both far from and only slightly below the source. Flows, in addition to the above hazards, can flow around well-built structures, preserving them but causing damage from water and mud. In addition to the direct hazards of a landslide moving out from under or onto structures or utilities, there is a major indirect hazard. Large slides generally do not stop moving until they reach the bottom of a valley. At which point they block streams, usually resulting in flooding.