Elevation difference products, schematic flow path, and volume polygons for the August 15, 2023 debris flow in Tahoma Creek, Mount Rainier

This dataset includes digital surface model (DSM) products, photographs, and shapefiles associated with the August 15, 2023 debris flow in Tahoma Creek at Mount Rainier, Washington. In this study, we created a post-event DSM using The Surface Extraction with TIN-based Search-space Minimization (SETSM) algorithm (Noh and Howat, 2017) using WorldView-2 stereo images collected on July 14, 2024. We additionally created a digital elevation model (DEM) difference product using our post-event DSM and a pre-event light detection and ranging (lidar)-derived digital terrain model (DTM) from the Washington State Department of Natural Resources (WaDNR) that was collected during the summer of 2022 (Washington Geological Survey, 2023). Before differencing, we aligned the post-event SETSM DSM to the pre-event WaDNR DTM in stable regions using CloudCompare (v. 2.13.2, 2026) and then applied that transformation to the full SETSM DSM. We identified stable regions (that have a combined area of ~87,000 m2) in Google Earth imagery as rock outcrops or planar areas with no trees. The standard deviation of Multiscale Model-to-Model Cloud Comparison (M3C2) (Lague and others, 2013) vertical distances in the stable regions used to align the two rasters is 2.73 m. The standard deviation of M3C2 vertical distances in the stable areas was 0.77 m, which were used to estimate volume in the deposit region. 
The two main raster products in this dataset are 1) the DEM difference file, cropped to the region of interest (14JUL2024_WV2_DoD.tif) and 2) the aligned SETSM DSM (14JUL2024_WV2_DSM_aligned.tif). The DSM difference file has been cropped to exclude areas of high-tree density and steep, non-planar regions. Note that some artifacts may still exist in the DEM difference product due to poor alignment and warping in the source area/glacial region, steep topography, and snow. 
There are also two shapefiles included, 1) polygons which outline areas of erosion and/or deposition (volume_polygons.zip) and 2) a polyline file which outlines the flow path and is categorized by flow style (flow_path.zip). The shapefiles were digitized using the pre-event WaDNR DTM, post-event WorldView images (from Sep. 21, 2023 and Aug. 18, 2023), post-event Google Earth imagery (from Jul. 3, 2024), and digital single-lens reflex camera (DSLR) photographs taken by Scott Beason during helicopter reconnaissance on Aug. 15, 2023 (DSLR_photos.zip), to help identify channel path and geometry. The DSLR photographs do not have geotags but we were able to identify their general locations using channel geometry and surrounding features. If a photograph was used to digitize a volume polygon, its filename is provided in the Source attribute field. The transition from debris flow to hyperconcentrated flow was identified using seismic and imagery methods described in Biegel and others (2026). The extent of the hyperconcentrated flow has only been digitized to where apparent flow is seen in the WorldView-2 image (captured Sep. 21, 2023) but may have extended further down the channel. We additionally only identified volume polygons in the hyperconcentrated region of the flow that were present in photographs and the DEM difference. There may be other debris flow features within the DEM difference in this region that were not digitzed because we were not able to constrain the timing of these signals and because they appear to be regular changes in channel geometry happening during this time span. 

Metadata for the two TIF files and DSLR photographs is described in Elevation_difference_products_DSLR_FGDC.xml. There are also individual metadata files describing the flow path and volume polygon shapefiles located within each zip file.

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
References:
Biegel, K.M., Collins, E.A., Allstadt, K.E., Conner, A., and Thomas, A.M., 2026, Seismic evidence of the transition from debris flow to hyperconcentrated flow at Mount Rainier, USA: Seismol. Res. Lett., In Review

CloudCompare (version 2.13.2) [GPL software]. (2026). Retrieved from https://www.cloudcompare.org/

Lague, D., Brodu, N., and Leroux, J., 2013, Accurate 3D comparison of complex topography with terrestrial laser scanner: Application to the Rangitikei canyon (N-Z), ISPRS Journal of Photogrammetry and Remote Sensing, v. 82, p. 10-26, https://doi.org/10.1016/j.isprsjprs.2013.04.009

Noh, M.-J., and Howat, I.M., 2017, The Surface Extraction from TIN based Search-space Minimization (SETSM) algorithm: ISPRS Journal of Photogrammetry and Remote Sensing, v. 129, p. 55-76, https://doi.org/10.1016/j.isprsjprs.2017.04.019

Washington Geological Survey, 2023, Rainier Wali 2022 project [lidar data]: originally contracted by Washington Dept. of Natural Resources. Accessed 2 Mar 2026, at https://lidarportal.dnr.wa.gov