Post-Fire Debris Flows

USGS WERC’s Dr. Karen Thorne and her research team are using drone imagery to understand how the 2018 Carr Fire affected ecosystems and cultural resources. The study, a collaboration with the National Park Service (NPS), focuses on Whiskeytown National Recreation Area in northern California. The drone images will help the WERC researchers identify changes in topography, cultural sites, debris...

The enhanced probability of catastrophic wildfires has increased our need to understand the risk of floods, erosion, and debris and contaminant transport in burned watersheds. This project investigates the relation between rainfall intensity and peak discharge; erosion and deposition processes; and water-quality impacts to minimize the loss of life and property resulting from post-wildfire floods.

Release Date: OCTOBER 15, 2018 USGS scientists have been pursuing a way to assess debris-flow hazards before a fire occurs.

Estimates of the probability and volume of debris flows that may be produced by a storm in a recently burned area, using a model with characteristics related to basin shape, burn severity, soil properties, and rainfall. Wildfire can significantly alter the hydrologic response of a watershed to the extent that even modest rainstorms can produce dangerous flash floods and debris flows. The USGS...

Fast-moving, highly destructive debris flows triggered by intense rainfall are one of the most dangerous post-fire hazards. The risk of floods and debris flows after fires increases due to vegetation loss and soil exposure. Cases of sudden and deadly debris flow are well documented along the western United States, particularly in Southern California. These flows are a risk to life and property...

What persuades someone to heed a debris flow or wildfire evacuation warning? SAFRR partners in emergency management are especially interested in the results of this study, now underway with Columbia's Center for Research on Environmental Decisions.

Debris flows are high-density slurries of water, rock fragments, soil, and mud that can have enormous destructive power. Wildfire can drastically increase the probability of debris flows in landscapes that have otherwise been stable. In 2010, the USGS developed the Cannon model to estimate postwildfire debris-flow probabilities and volumes in burned areas. In 2013, with the help of U.S. Forest...

Wildfire is a natural process in forest ecosystems, and occurs with varying frequencies and severities depending on landscape characteristics, climatic conditions, and the historical fire regime. Although attention often is focused on the potential damages from wildfire in the wildland-urban interface, wildfire also presents a threat to critical infrastructure including flood water conveyances and...