Landslides occur in all 50 states and territories and they affect lives, property, infrastructure, and the environment. Understanding when, where, and how landslides occur can help to reduce the risk of living with these natural hazards.
What is a landslide?
Landslides are the downslope movement of earth materials (rock, debris, and soil) at rates that range from inches per year to tens of miles per hour. When landslides occur, they affect lives, property, infrastructure, and the environment. Some landslides can move faster than a person can run. They can happen with no notice or can take place over a period of days, weeks, or longer.
Where do landslides happen?
Landslides occur in every U.S. state and 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.
Why do landslides occur?
Landslides occur when the forces that form them overcome forces resisting their formation. This can happen quickly, such as during an earthquake or rainstorm, or slowly, like in stream or shoreline erosion, permafrost melting in a warming climate, or gradual weakening of hillslope materials.
Signs of Landslide Development / Movement
Landslides are dangerous and very difficult to predict. Some landslides may provide clues that they are about to happen; others may happen suddenly without any warning signs. A few common indicators and example photos can be seen here:
New cracks or deformation in the ground
Separation of structures or soil from foundation
Deformed fences, tilting trees, or leaning poles
Other Resources
Why should you care about landslides?
How to Prepare for a Landslide
What to do after a landslide
Related Links
- USGS Postfire Debris-flow Hazard Assessment Viewer
- State Geological Surveys | Association of American State Geologists
- State Emergency Management Agencies | USAGov (note that your county or city Emergency Manager may have jurisdiction in your community)
- National Association of Conservation Districts
- American Red Cross | Disaster Preparedness Plan | Make a Plan
Landslides occur in all 50 states and territories and they affect lives, property, infrastructure, and the environment. Understanding when, where, and how landslides occur can help to reduce the risk of living with these natural hazards.
What is a landslide?
Landslides are the downslope movement of earth materials (rock, debris, and soil) at rates that range from inches per year to tens of miles per hour. When landslides occur, they affect lives, property, infrastructure, and the environment. Some landslides can move faster than a person can run. They can happen with no notice or can take place over a period of days, weeks, or longer.
Where do landslides happen?
Landslides occur in every U.S. state and 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.
Why do landslides occur?
Landslides occur when the forces that form them overcome forces resisting their formation. This can happen quickly, such as during an earthquake or rainstorm, or slowly, like in stream or shoreline erosion, permafrost melting in a warming climate, or gradual weakening of hillslope materials.
Signs of Landslide Development / Movement
Landslides are dangerous and very difficult to predict. Some landslides may provide clues that they are about to happen; others may happen suddenly without any warning signs. A few common indicators and example photos can be seen here:
New cracks or deformation in the ground
Separation of structures or soil from foundation
Deformed fences, tilting trees, or leaning poles
Other Resources
Why should you care about landslides?
How to Prepare for a Landslide
What to do after a landslide
Related Links
- USGS Postfire Debris-flow Hazard Assessment Viewer
- State Geological Surveys | Association of American State Geologists
- State Emergency Management Agencies | USAGov (note that your county or city Emergency Manager may have jurisdiction in your community)
- National Association of Conservation Districts
- American Red Cross | Disaster Preparedness Plan | Make a Plan