Landslides - 9 of 22

Landslides FAQs - 22 Found

When does the U.S. Geological Survey issue a landslide advisory, and under what conditions?

The U.S. Geological Survey derives its leadership role in landslide hazard-related work from the Disaster Relief Act of 1974 (the Stafford Act). The Director of the USGS has been delegated the responsibility to issue warnings for an earthquake, volcanic eruption, landslide, or other geologic catastrophe (1974 Disaster Relief Act 41 U.S.C. 5201 et seq). 


The USGS Landslide Hazards Program, in cooperation with other federal, state, and local agencies, currently has experimental efforts to forecast landslides:


  • rainfall-triggered debris flows in burned areas in southern California
  • rainfall-triggered landslides in the Seattle, Washington, area
  • rainfall-triggered landslides associated with hurricanes that make landfall on the U.S. east coast


When we have sufficient data or knowledge of a particular area we can provide information on potential hazards—for example, if rainfall intensity-duration thresholds for landslide activity have been developed for an area we can issue an advisory, based on rainfall data. The occurrence of most landslides depends strongly on weather conditions, so the USGS works in conjunction with the National Weather Service (NWS) to issue advisories regarding the potential for landslide activity. Most landslide advisories based on USGS information reach the public through NWS flash flood warnings and other hazardous weather statements.


The USGS Landslide Program posts landslide alerts on its homepage, which links to the main USGS Web site alerts. There are also archives of past landslide alerts.


For debris-flow alerts in areas burned by southern California wildfires, please see the NOAA/USGS Demonstration Flash-Flood and Debris-Flow Early-Warning System.

Tags: Landslides, Liquefaction, Maps, Precipitation, Soils