DIRECT LANDSLIDE COSTS IN THE UNITED STATES: WHO BEARS THE BURDEN? A PILOT LANDSLIDE LOSS STUDY FOR THE STATES OF WASHINGTON AND OREGON WITH AN APPLICATION TO THE 50 UNITED STATES

Landslides can result in a heavy financial burden for individual property owners and governments, since the majority of basic insurance policies (both private and commercial ) do not cover losses from landslides. Landslide loss investigation reports are rare, and those that are available either aggregate losses with other hazards, merge landslide losses with other unrelated costs, or place landslide cost data in other categories, such as general highway maintenance or flood damage. In addition to the scarcity of loss studies, those that exist rarely identify the entities that bear those costs. This study will obtain direct landslide loss figures for the states of Washington and Oregon dating from the early 1900s to present day. It will also include an accounting of how landslide costs are shifted from one entity to another, resulting in uncertainty as to who is actually paying for direct losses. Finally, the study will also include a discussion of indirect losses; these losses are often much higher than direct costs, and include a wider population of those that are affected monetarily. The methodology to assess landslide losses and the availability of loss data have significantly improved during the last 30 years. These improvements may provide a more accurate assessment of what the real losses are, what entities bear those costs, what risks exist, and what cost-benefit approaches should be used to mitigate landslide hazard. This study is preliminary to a larger study that will provide an updated average landslide loss figure for the entire United States that reflects the modern advances in historical data acquisition and analysis, and the increased landslide hazard exposure of sectors of the U.S. population.