Hazard Assessment Requirements

Post-fire debris-flow hazard assessments for recently burned areas in the western United States are provided free to any interested Federal, State, or Local Agency, or to any private organization. These assessments rely upon the differenced normalized burn ratio (dNBR) image and field-validated estimates of soil burn severity in geospatial format.

Organizations requesting post-fire debris-flow hazard assessments must supply the following geospatial data as input to the models:

1. A differenced normalized burn ratio (dNBR) image in raster format (GeoTIFF or ArcGIS raster).
   • The original dNBR raster is used as a model input. The dNBR should not be classified otherwise altered (i.e., dNBR256 or dNBR4 do not work as model inputs).  Pixel values should range from approximately-32000 to 1600.  See an example dNBR from the 2024 Park Fire.  

Media

Sources/Usage: Public Domain. View Media Details

• Field validated soil burn severity in raster format (GeoTIFF or ArcGIS raster) where:

  0 = unburned
  1 = unburned or low soil burn severity
  2 = low soil burn severity
  3 = moderate soil burn severity
  4 = high soil burn

  If field-validated soil burn severity data are unavailable, it is possible to use a Burned Area Reflectance Classification (BARC4) raster as a substitution.  Please note that the use of BARC4 data increases the degree of uncertainty in the model estimates.

  Media

  

  Sources/Usage: Public Domain. View Media Details
• Most recent fire perimeter as a shapefile or a feature class.

Please direct requests and required input data, or questions about the assessment process to jkostelnik@usgs.gov.

Response time is dependent upon the number of assessments that have been previously requested, and if the input data are in the required format.