QGISHydro Webinar 4: Stream & Catchment Delineation
Channel: Hans van der Kwast
Date: 2020-04-11

In this series of 7 free webinars during the Corona Crisis, Kurt Menke and Hans van der Kwast demonstrate the 7 chapters of the book QGIS for Hydrological Applications - Recipes for Catchment Hydrology and Water Management.

In this webinar we demonstrate how to perform stream and catchment delineation in QGIS using the SAGA tools from the toolbox. We also show how to visualise the flow direction map and use the 3D view.

Join us next Friday from 9 pm CEST / 7 pm UTC. Register at http://loc8.cc/qgishydro 

The book is available at http://locatepress.com/hyd

(c) OpenStreetMap Contributors

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Note that with the new dependencies in QGIS this will not work.
For work around see: https://youtu.be/B1LMOOPMWgo
And also see: https://github.com/qgis/QGIS/issues/44514
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0:00 Introduction QGISHydro Webinar 4
7:59 Start demo Stream and Catchment Delineation
10:35 Download SRTM tiles
14:00 Mosaic SRTM tiles to virtual layer
15:38 Reproject and subset DEM
20:28 Fill sinks
22:28 Profile tool
23:33 Style DEM
26:18 Calculate Strahler orders
27:08 Style ordinal raster
28:08 Calibrate Strahler orders
31:50 Delineate streams and basins, flow direction
34:39 Style channels using calibrated Strahler orders
36:55 Style flow direction layer with ramp
42:30 Style flow direction using Crayfish plugin
46:22 Define outflow point
46:47 Delineate catchment
49:17 Polygonize the catchment
52:43 Clip layers to catchment boundary
56:20 Visualise in 3D view
57:48 Q & A
1:07:25 Shameless plugs