Emergency Assessment of Post-Fire Debris-Flow Hazards

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 U.S. Geological Survey conducts post-fire debris-flow hazard assessments for select fires in the western U.S. Using geospatial data related to basin morphometry, burn severity, soil properties, and rainfall characteristics, USGS researchers estimate the probability and volume of debris flows that may occur in response to a storm.