Landslide Basics
What is a landslide?
Where do landslides occur?
Slumgullion Landslide
When do landslides occur?
Post-Cyclone Gabrielle helicopter reconnaissance in the Auckland region of New Zealand
How to prepare for a landslide?
Woody material deposited by a debris-flow near the area burned by the 2020 Cameron Peak fire
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 occur in all 50 states and territories where they affect lives, property, infrastructure, and the environment. 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. Some landslides can move faster than a person can run. Landslides can happen with no notice or can take place over a period of days, weeks, or longer.
Where do landslides occur?
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.
Why do landslides occur?
Landslides occur when forces that form them overcome forces resisting their formation.
What are the 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.
Why should I care about landslides?
Landslides kill people and destroy property.
How do I prepare for a landslide?
If you live on or below a slope, here are some simple steps you can take to identify a landslide hazard and reduce your landslide risk.
What do I do after a landslide has occurred?
Depending on the severity of the landslide, you may not be able to return home right away. If authorities say it is safe to return to your home, continue to be prepared to leave the area immediately if you observe unusual activity.
Resources
- 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