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I have a DEM I want to generate a HAND for and want to do so in QGIS. Does anyone know of any plugins or the processing steps to be able to do this?

3 Answers 3

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Actually, I did not generate HAND from DEM before, but based on High Resolution Hydrography and Hydrologic Modeling PDF reference file, they use TauDEM tool accessed from ArcGIS, as you can see in Slide No. 10. TauDEM tool can be accessed from QGIS: TauDEM algorithm provider but you need to it install it separately from Utah State University and configure it manually.

Here is the TauDEM tool in QGIS.

enter image description here

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  • Which tool is for the Height Above the Nearest Drainage (HAND) according to your image? Commented Apr 3, 2019 at 21:48
  • @iliasm I am not referring to the HAND tool, I am referring to the TauDEM tool in general. As I said, I did not use HAND tool before, but according to the PDF slides (I fixed the link), the author used TauDEM tools for the analysis. You can refer to the PDF for more information.
    – ahmadhanb
    Commented Apr 4, 2019 at 1:12
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I would like to give a more detailed answer to this question. You need to use the above-mentioned tool and the workflow is displayed below. enter image description here

I executed this process (without 'NHD HR Flowline' and 'NHDPlus Flowline 1:1000000' files) but the values of HAND were higher than expected.

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With the PCRaster Tools plugin in QGIS you calculate HAND as follows:

  1. Convert DEM to PCRaster format as scalar
  2. Calculate local drain direction raster with lddcreate tool
  3. Calculate flow accumulation with accuflux tool
  4. Derive a boolean drainage network using a threshold of flow accumulation
  5. Assign unique IDs to each cell fo the drainage network. Use the uniqueid tool and convert the result to a nominal raster
  6. Calculate catchments of each unique ID with the subcatchment tool
  7. Use the areaminimum tool to get the lowest elevation in each subcatchment, which is the elevation of the drainage cell.
  8. Use the Raster Calculator to subtract the result of (7) from the DEM.

A graphical model and processing script can be found in the PCRaster QGIS Resource Sharing repository.

This video shows the steps in QGIS.

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