I am attempting to create a flood depth raster so I can run the Flood Impact Analysis Solution (FIAS) toolset in my water district. I am following the Creating Flood Depth Rasters for Flood Impact Analysis guidance document, but am getting stuck on the addressing flat areas section. When I run the Arc Hydro Identify Flat Areas tool on the example DEM they provide, the tool completes successfully, but no rasters or layers are generated. I am using ArcGIS Pro 3.6.1.
Identify Flat Areas
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Tool Path
Input DEM Raster dtm_extent1.tif
Flat Terrain Angle Threshold 1
Search Distance 10
Skip Distance 0
Flat Landform List Flat
Minimum Flat Area Threshold 2000 SquareMeters
Output Landform Raster C:\LOCATION\ArcHydro\FIAS\Layers\dtm_extent1_landform.tif
Output Flat Area Raster C:\LOCATION\ArcHydro\FIAS\Layers\dtm_extent1_flat.tif
Output Flat Area Polygon C:\LOCATION\ArcHydro\FIAS\FIAS.gdb\Layers\AHFlatPoly
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Messages
Start Time: Wednesday, February 18, 2026 5:45:33 PM
Succeeded at Wednesday, February 18, 2026 5:45:34 PM (Elapsed Time: 0.75 seconds)
Are results automatically added to display for geoprocessing tools?
Have you confirmed that the 2 *.tif files don't exist in the output folders?
If they do exist and they are listed in the map's table of contents, do a right-click on one of the layers and zoom-to-layer (maybe a different ill-defined coordinate system)
Also... a related thread Arc Hydro Characterize DEM - Flat Area Raster step... - Esri Community
Hi Dan,
Thanks for your response. When I run the tool, no files are generated. I've checked the output locations and nothing appears, and nothing is added to the ToC.
Unfortunately, the AH download link that Dean shared in his response to the other post is broken. I will try to re-download my version of AH to see if that fixes anything.
Arc Hydro Tools Downloads for ArcGIS Pro & ArcMap
Downloading and Installing Arc Hydro Tools | 2023
hoping this is the download link access point
Yes it is, thank you. Reinstalling did not seem to fix the issue. I did notice that the installation file states ArcHydroToolsforArcGISPro3.5.msi, so I am wondering if this is a versioning issue, since I am running ArcGIS Pro V3.6.1.
dont' know, but Arc Hydro Tools Downloads for ArcGIS Pro & ArcMap
says you have to request the download. I am not going to go through the steps to see if they have a version for 3.6