Jonathan M. King Jaime Kostelnik Jason W. Kean Katherine R. Barnhart Andrew P. Graber Francis K. Rengers Matthew A. Thomas 20250602 vector digital data https://doi.org/10.5066/P14EWYME Wildfire can substantially alter the hydrologic response of watersheds to rainfall, and debris-flow activity is among the most destructive consequences of these events. To assist federal, state, and local agencies in planning for postfire hazards, the U.S. Geological Survey conducts debris-flow hazard assessments for recent wildfires. This collection contains the results of those assessments since 2025. Each child item holds the results for a given version of a hazard assessment. The data map the likelihood and potential volume of debris flows across the burn area for a series of design rainstorms. The data also include estimates of the rainfall rates required to trigger debris flows. Assessment results are generally representative of the conditions immediately after the fire; however, additional versions of the hazard assessment are available for some fires. These additional versions may represent preliminary assessments before the fire is fully contained and/or a reassessment of the hazard after one or more years of postfire vegetation recovery. The files, data fields, and metadata included in each assessment strictly conform to the PWFDF Data Specification. You can find archived versions of all current and historical versions of the data specification here: https://ghsc.code-pages.usgs.gov/lhp/ocelote/data-spec/archive/index Collected hazard assessments are typically produced via the Landslide Hazards Program's ocelote codebase. The source code for the codebase is available here: https://code.usgs.gov/ghsc/lhp/ocelote This collection is intended to archive results from debris-flow hazard assessments for recent, recovering, and historical burn areas. 20250101 Collection Start Date In work As needed -180.0000 180.0000 90.0000 -90.0000 ISO 19115 Topic Category geoscientificInformation USGS information products data release USGS Thesaurus landslides hazards fires maps and atlases landslide susceptibility assessment hazard preparedness mathematical modeling USGS Metadata Identifier USGS:6818f950d4be0208bc3e0165 No access constraints. Please see 'Distribution Information' for details. These data are marked with a Creative Common CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. U.S. Geological Survey, Landslide Hazards Program GHSC Data Steward GHSC Data Steward mailing and physical

1711 Illinois St

Golden CO 80401 US 3032738500 ghsc_metadata@usgs.gov Input datasets may be provided by partners of the Landslide Hazards Program. These partners include, but are not limited to: BAER, GTAC, and EROS. Assessments are reviewed by USGS personnel prior to publication. Personnel may modify stream network delineation and modeling parameters in order to ensure quality. No formal logical tests were performed. This collection represents postfire debris-flow hazard assessments released by the U.S. Geological Survey Landslide Hazards Program since 2025. Assessments are produced by USGS personnel running the ocelote codebase. To produce an assessment, the codebase: * Characterizes a watershed, * Delineates a stream segment network, * Filters the network to model-worthy segments, and then * Runs hazard assessment models on the segments and their catchment basins. Assessment results are quality controlled by operational personnel, who may modify stream segment delineation and modeling parameters to ensure quality. 20250101 U.S. Geological Survey, Landslide Hazards Program GHSC Data Steward GHSC Data Steward mailing and physical

1711 Illinois St

Golden CO 80401 US 3032738500 ghsc_metadata@usgs.gov 0.0197512473 0.0254178603 Decimal seconds WGS_1984 WGS 84 6378137.0 298.257223563 This repository is a collection of postfire debris-flow hazard assessments produced by the U.S Geological Survey Landslide Hazards Program. Please refer to the collection's child items for the entity and attribute metadata associated with individual assessments. King., J.M., Kostelnik, J., Kean, J.W., Barnhart, K.R., Graber, A.P., Rengers, F.K., Thomas, M.A., 2025, Post-Wildfire Debris-Flow Hazard Assessment (PWFDF) Collection: U.S. Geological Survey data release, https://doi.org/10.5066/P14EWYME U.S. Geological Survey - ScienceBase mailing address

Denver Federal Center

Building 810

Mail Stop 302

Denver CO 80225 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Digital Data https://doi.org/10.5066/P14EWYME None 20250602 U.S. Geological Survey, Landslide Hazards Program GHSC Data Steward GHSC Data Steward mailing and physical

1711 Illinois St

Golden CO 80401 US 3032738500 ghsc_metadata@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998