Complete Updated Workflow Stream and Catchment Delineation in QGIS
Channel: Hans van der Kwast
Date: 2021-10-28

This video shows how to derive streams and catchments from SRTM DEM tiles from scratch in QGIS 3.16 LTR. The workflow uses different plugins: QuickMapServices, SRTM-Downloader, PCRaster Tools and GRASS tools.

A complete tutorial can be found at GIS OpenCourseWare: https://courses.gisopencourseware.org/mod/book/view.php?id=818

Note that the procedure uses the PCRaster Tools plugin. You need to install PCRaster prior to using the plugin. Here's the link to the documentation: https://jvdkwast.github.io/qgis-processing-pcraster/

0:00 Introduction
0:20 Define study area extent
3:04 Download SRTM tiles
4:30 Mosaic SRTM tiles
5:24 Reproject and subset DEM
7:04 Style the DEM
8:37 Convert DEM to PCRaster format
9:26 Fill sinks and calculate flow direction
10:40 Style flow direction with directional ramp
15:50 Calculate Strahler orders
16:50 Calibrate Strahler orders
19:29 Derive channel network
23:25 Style channels with Strahler orders
25:52 Smooth channel network
27:13 Define outlet of catchment
29:02 Derive catchment of outlet
29:37 Polygonize catchment
31:00 Style catchment boundary polygon with inverted polygon shapeburst fill
33:10 Clip channels with catchment boundary
33:54 Store results and project in a GeoPackage

#QGIS #QGISHydro #GISOCW