Landslides occur in every state and U.S. territory including the Appalachian Mountains, the Rocky Mountains, the Pacific Coastal Ranges, and some parts of Alaska and Hawaii. Any area composed of very weak or fractured materials resting on a steep slope can and will likely experience landslides.
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Where do landslides occur?
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Landslides typically start on slopes, most commonly on steeper slopes
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Landslides usually occur in areas where they've happened before
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Landslides typically occur on slopes with fractured materials (e.g., rock, debris, ice), deep soils, or thin soils over bedrock.
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Slopes with mature, healthy, native vegetation tend to have strong root systems that help hold soil in place, which may reduce the landslide hazard
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Some landslides can travel hundreds to thousands of feet in stream channels, far from where the landslide started
Landslide susceptibility maps across the U.S.
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Although the physical cause of many landslides cannot be removed, geologic investigations, quality engineering practices, and effective enforcement of land-use management regulations can reduce landslide hazards. USGS scientists continue to produce landslide susceptibility maps for many areas in the United States. In every state, USGS scientists monitor streamflow, noting changes in sediment load carried by rivers and streams that may result from landslides. Hydrologists with expertise in debris and mudflows are studying these hazards in volcanic regions.
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