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Landslides affect all 50 states and U.S. territories, where they cause 25 to 50 deaths and more than $1 billion in damages each year. Geoscientists study and monitor landslides to identify at-risk areas, prepare populations, and improve our understanding of why, when, and where landslides happen.


2014 Oso, Washington Landslide. Image Credit: USGS/Photo by Mark Reid

Landslides are masses of earth, rock, or debris that move down slopes. Landslides are triggered by one event, but many causes can weaken slopes over time and make them more likely to fail when there is a triggering event. These causes can be both natural and artificial. Landslides often occur in areas with oversteepened slopes, weak soils/bedrock, or de-vegetated slopes (whether by human deforestation or natural events such as wildfires).[1] Some of the most damaging landslides are triggered by water, typically from intense short-term rainfall or long-term saturation of the slope. Both natural and human activities (such as irrigation or seepage) can saturate hillsides. Earthquakes and volcanic eruptions also cause damaging landslides.[1]   Read more

Frequently Asked Questions

Latest News

Cracked road from earthquake
January 30, 2018 On January 30, the Senate Committee on Energy and Natural Resources held a full committee hearing to address the role of the U.S. Geological Survey (USGS), U.S. Forest Service (USFS), and National Oceanic and Atmospheric Administration (NOAA) in preparing for and responding to...
March 22, 2017 Senators Maria Cantwell (D-WA) and Lisa Murkowski (R-AK) introduced the bipartisan National Landslide Preparation Act (S.698) on March 22. The bill directs the U.S. Geological Survey (USGS) to establish a National Landslide Hazards Reduction Program. This program would identify and...
Mount St. Helens
July 12, 2016 The Hazards Caucus Alliance, a network of organizations that promotes nationwide natural disaster resilience, held a briefing to highlight the role that science plays in protecting communities that are vulnerable to lahars. Introductory remarks from Senator Lisa Murkowski (R-AK) were...
Capitol at night
March 17, 2016 Congresswoman Suzan DelBene (D-WA) has introduced new legislation in an effort to decrease losses and damages as a result of landslides.  The new bill, the National Landslide Loss Reduction Act (H.R. 4776) would create the National Landslide Hazards Reduction Program and two...

Case Studies & Factsheets

Fig. 1. A 1995 landslide in Overland Park, Kansas, destroyed two homes and damaged four lots. Credit: Kansas Geological Survey

Defining the Problem Damaging landslides occur even in vertically challenged states like Kansas (Fig. 1). It is important to be able to delineate landslide hazard areas in order to develop appropriate land-use plans. In Leavenworth County, Kansas, geologic maps combined with maps of landslide...

Fig. 1. Homeowners and emergency managers are still coping with debris flows and the aftermath of the 2002 Missionary Ridge wildfire near Durango, CO. Credit: P. Winkworth

Defining the Problem Wildfires, such as the Missionary Ridge fire that burned for more than a month in 2002 near Durango, Colorado (Fig. 1), and their aftermath can cause subsequent property and environmental damage. Many areas denuded by the fire are now susceptible to rapid erosion during...


More than just volcanic eruptions Volcanic eruptions are a serious hazard. But at many stratovolcanoes in Washington, Oregon, Northern California, and Alaska, landslides and debris flows can be just as dangerous. Some of these - especially volcanic mudflows (lahars) - are directly triggered by...

Fig. 3. U.S. Highway 85 crossing the Little Missouri River. Seventy-five percent of the rocks in this photograph, all of those in the foreground and the rocks along the north valley wall in the background have slid and are out of place. Credit: E. Murphy

Defining the Problem U.S Highway 85 and ND Highway 22, along with numerous county roads, buildings, pipelines, and power lines, have been constructed over existing landslides in the Little Missouri Badlands of western North Dakota. Since 1980, the repair and rerouting of damaged sections of...

Cover of AGI Factsheet 2018-003--Using Geologic Maps to Reduce Landslide Risk

Geologic Maps and Landslide Hazards A geologic map is key to understanding landslide risk. The U.S. Geological Survey (USGS) and numerous state geological surveys around the nation prioritize the mapping of landslide-prone areas. Understanding landslide risk is crucial in making decisions around...

Fig.1. Home in Oakland, CA, destroyed by landslides in 1958. Source: J. Coe, USGS

Defining the Problem The geologic history of the Oakland, California, area has produced steep hillsides and unstable rock and soil that generate damaging landslides during severe storms and wet winters (Fig. 1 and 2). During the 1997-98 rainy-season, the two-county area surrounding Oakland...

GOLI Online Courses

Landslides and Mass Wasting
Course Type: GOLI Online Course

This course is designed to be an introduction to the subject of landslides or mass wasting. Landslides or mass wasting occur in both solid bedrock and in poorly-consolidated sediments. Concerning the latter, loose sands, clays and soft shales can prove to be quite problematic. These type of...

Geological Surveys Database Publications

1980, Arizona Geological Survey
On May 3, 1887, a major earthquake shook much of the southwest United States and Mexico, an area of nearly two million square kilometers (Figure 1). This seismic event, with an estimated magnitude of 7.2 (DuBois and Sbar, in press), caused 51 deaths in northern Sonora, and major destruction of...
2006, United States Geological Survey

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2009, Pennsylvania Geological Survey

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2012, Utah Geological Survey

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2011, Nevada Bureau of Mines and Geology

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2017, United States Geological Survey
The U.S. Geological Survey (USGS) Landslide Hazards Program conducts landslide hazard assessments, pursues landslide investigations and forecasts, provides technical assistance to respond to landslide emergencies, and engages in outreach. All of these activities benefit from the availability of...
2014, United States Geological Survey

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2014, United States Geological Survey

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2015, United States Geological Survey
Elevation data are essential to a broad range of applications, including forest resources management, wildlife and habitat management, national security, recreation, and many others. For the Commonwealth of Pennsylvania, elevation data are critical for natural resources conservation (including the...
2016, United States Geological Survey

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