| Landslides and related phenomena cause substantial damage (Figure 7.1) and loss of l | Landslides and related phenomena cause substantial damage (Figure 7.1) and loss of life. In the United States, between 25 and 50 people are killed each year by landslides. This number increases to between 100 and 150, if collapses of trenches and other excavations are included. The total annual cost of damages is about $3.5 billion.1, 2 Landslides and other types of ground failure are natural phenomena that would occur with or without human activity. However, human land use has led to an increase in these events in some situations and a decrease in others. For example, landslides may occur on previously stable hillsides that have been modified for housing development; on the other hand, landslides on naturally sensitive slopes are sometimes averted through the use of stabilizing structures or techniques. The goal of the U.S. landslide hazards program is to reduce losses from landslides. Key elements are research, mapping the landslide hazard, real-time monitoring of landslides, assessment of losses, identifying and implementing loss reduction measures, emergency preparedness, and education of the public about the landslide hazard.2 |