What should I know about wildfires and debris flows?
Wildland fires are inevitable in the western United States. Expansion of human development into forested areas has created a situation where wildfires can adversely affect lives and property, as can the flooding and landslides that occur in the aftermath of the fires. There is a need to develop tools and methods to identify and quantify the potential hazards posed by landslides produced from burned watersheds.
Post-fire landslide hazards include fast-moving, highly destructive debris flows that can occur in the years immediately after wildfires in response to high intensity rainfall events, and those flows that are generated over longer time periods accompanied by root decay and loss of soil strength. Post-fire debris flows are particularly hazardous because they can occur with little warning, can exert great impulsive loads on objects in their paths, and can strip vegetation, block drainage ways, damage structures, and endanger human life. Wildfires could potentially result in the destabilization of pre-existing deep-seated landslides over long time periods.
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Wildland Fire Science—Supporting wildland fire and land management
The U.S. Geological Survey's Wildland Fire Science Program produces fundamental information to identify the causes of wildfires, understand the impacts and benefits of both wildfires and prescribed fires, and help prevent and manage larger, catastrophic events. Our fire scientists provide information and develop tools that are widely used by...
Steblein, Paul F.; Miller, Mark P.; Soileau, Suzanna C.
Characterizing 12 years of wildland fire science at the U.S. Geological Survey: Wildland Fire Science Publications, 2006–17
Wildland fire characteristics, such as area burned, number of large fires, burn intensity, and fire season duration, have increased steadily over the past 30 years, resulting in substantial increases in the costs of suppressing fires and managing damages from wildland fire events (National Academies of Sciences, Engineering, and Medicine, 2017)....
Steblein, Paul F.; Miller, Mark P.
The 3D Elevation Program—Landslide recognition, hazard assessment, and mitigation support
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 high-resolution, three-dimensional (3D) elevation...
Lukas, Vicki; Carswell, Jr., William J.
Real-time monitoring of landslides
Landslides cause fatalities and property damage throughout the Nation. To reduce the impact from hazardous landslides, the U.S. Geological Survey develops and uses real-time and near-real-time landslide monitoring systems. Monitoring can detect when hillslopes are primed for sliding and can provide early indications of rapid, catastrophic movement...
Reid, Mark E.; LaHusen, Richard G.; Baum, Rex L.; Kean, Jason W.; Schulz, William H.; Highland, Lynn M.
The Landslide Handbook - A Guide to Understanding Landslides
This handbook is intended to be a resource for people affected by landslides to acquire further knowledge, especially about the conditions that are unique to their neighborhoods and communities. Considerable literature and research are available concerning landslides, but unfortunately little of it is synthesized and integrated to address the...
Highland, Lynn M.; Bobrowsky, Peter
Wildfire hazards—A national threat
Wildfires are a growing natural hazard in most regions of the United States, posing a threat to life and property, particularly where native ecosystems meet developed areas.However, because fire is a natural (and often beneficial) process, fire suppression can lead to more severe fires due to the buildup of vegetation, which creates more fuel.In...
Landslide Hazards - A National Threat
Landslides occur and can cause damage in all 50 States. Severe storms, earthquakes, volcanic activity, coastal wave attack, and wildfires can cause widespread slope instability. Landslide danger may be high even as emergency personnel are providing rescue and recovery services. To address landslide hazards, several questions must be considered...
Southern California landslides-an overview
Southern California lies astride a major tectonic plate boundary defined by the San Andreas Fault and numerous related faults that are spread across a broad region. This dynamic tectonic environment has created a spectacular landscape of rugged mountains and steep-walled valleys that compose much of the region’s scenic beauty. Unfortunately...
A NOAA-USGS demonstration flash-flood and debris-flow early-warning system
NOAA-USGS Debris-Flow Warning System - Final Report
Landslides and debris flows cause loss of life and millions of dollars in property damage annually in the United States (National Research Council, 2004). In an effort to reduce loss of life by debris flows, the National Oceanic and Atmospheric Administration's (NOAA) National Weather Service (NWS) and the U.S. Geological Survey (USGS) operated an...
Landslide types and processes
Highland, Lynn
Debris-Flow Hazards in the United States
Highland, Lynn; Ellen, Stephenson D.; Christian, Sarah B.; Brown, William M.
Fast Fire Facts from USGS
You’ve got questions about USGS fire science. We’ve got answers.
Huge landslide on California’s Big Sur coast continues to change
The Mud Creek landslide on California’s Big Sur coast keeps eroding.
USGS helping to monitor and assess huge Big Sur landslide
USGS is collecting and analyzing air photos to help monitor a huge landslide that occurred May 20 on California’s Big Sur coast.
Predicting Postfire Debris Flows Saves Lives
When wildfires spread and scorch the earth, people like Penny Luehring have to act fast. Secondary impacts such as debris flows can be devastating to nearby communities.
Imagery Reveals More Landslides in Western Columbia Gorge
New mapping in the western portion of the Columbia Gorge in Skamania County, Washington, shows previously unrecognized landslides beneath dense forest cover.
EarthView–Landslide Spreads 6 Miles Across Glacier Bay National Park
Two snapshots from Landsat show the extent of a landslide in an Alaska National Park.
Debris Flows May Affect Southern California Communities
Rainstorms this year in the area burned by the Station Fire have the potential to trigger debris flows that may impact neighborhoods at the base of the San Gabriel Mountains as well as areas in Big Tujunga Canyon, Pacoima Canyon, Arroyo Seco, West Fork of the San Gabriel River, and Devils Canyon, according to an assessment released today by the U.S. Geological Survey.
NOAA, USGS Warning System to Help Protect Southern Californians from Debris Flows and Flash Floods
A debris flow and flash flood warning system developed jointly by NOAA's National Weather Service and the U.S. Geological Survey will help protect Southern Californians from potentially devastating debris flows-commonly known as mud slides- and flash floods in and around burn areas created by the recent wildfires.
Post-Fire Debris Flow Hazards Shown on New USGS Maps
The U.S. Geological Survey (USGS) has posted new maps on the Internet showing basins with the greatest potential for producing mudslides as a result of the devastating October fires in Southern California.
PubTalk 10/2018 — Post-fire debris flow early warning
Title: Post-Fire Debris-Flow Early Warning: The case for forecast-based warning systems
- Post-fire debris flows can initiate after only a few minutes of intense rain, and during the first storm following wildfire.
- Early warning systems must provide sufficient time to make informed decisions and take reasonable preventative action.
- If you're
Post-wildfire Flood and Debris Flow: 2014 Silverado Fire
In 2014, the Silverado Fire burned approximately 4 km^2 in Orange County, California. After the fire, the USGS installed an automated rain-triggered camera to monitor post-wildfire flooding and debris flow at the outlet of a small 0.6 km^2 basin within the burn area. This video shows the initial surge and peak flow triggered by an intense rainstorm on July 19, 2015. The
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Debris flow as result of 2013 Beaver Creek Fire, Idaho
Debris Flow Damage in California
House damaged by debris flows generated in Mullally Canyon in response to a rainstorm on February 6, 2010. The drainage basin above this home was burned the previous summer by the Station Fire, the largest fire in the history of Los Angeles County.
Debris Flow Damage
House engulfed by debris flows generated in response to a rainstorm on February 6, 2010. This house was west of Briar Wood Canyon in southern California. The small, but steep and rugged drainage basin above this home was burned the previous summer by the Station Fire, the largest fire in the history of Los Angeles County.
LS Post Fire Debris Flow
Downstream impacts of a post-fire debris-flow in Mullally Canyon on February 6, 2010, near La Canada-Flintridge, California. Debris flow was generated during a burst of high-intensity rainfall over the area burned by the September 2009 Station Fire.
Debris Flow Danger Follows Storms in Southern California
The powerful storms that swept through Southern California dumped a lot of rain in that region, leaving behind the danger of debris flows.
Sue Cannon, USGS research geologist, explains the hazardous situation facing residents in and near the San Gabriel Mountains, how people in the area can respond to these hazards, and what the USGS is doing to respond.
USGS and California Wildfires: Post Fire Debris Flow (part 2)
Jim Bowers, USGS, California Hydrologic Monitoring Program Chief talks about the potential for debris flows in central Orange County, Modjeska Canyon, as a result of the 2007 fires.
USGS and California Wildfires: Post Fire Debris Flow (part 1)
Jim Bowers, USGS, California Hydrologic Monitoring Program Chief, talks about an historic streamflow site that was buried by debris flows as a result of the 2003 fires.
The Fire's Out, but Danger Remains: Post-Wildfire Debris Flows
After the smoke from wildfires clears, debris flows can become a big problem. USGS Research Geologist Sue Cannon talks about how.
Debris Flow from 2006 Floods in Southern Arizona
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Post-fire Debris Flow
Debris Flow in Cable Canyon following the 2003 Old Fire in the San Bernardino Mountains, California.