Watershed

Watershed is a feature to determine where the water flows based on the topography. To activate the watershed feature, user can go to Earthwork module > Terrain > Click ‘Watershed’

1. DEM Grid size
   • The smaller the value, more sub-catchments will be introduced and more precise terrain, as well as more refined the whole DEM, will be generated.
2. TauDem Threshold
   • for user to have better control on the streamline generation, the smaller the value, more streamline will be generated which will make it easier for user to identify catchment and flow for drainage design.
3. Nc
   • When the software generates the watershed delineation, some of the catchment may look rough or coarse, and the user may wish all of the catchment’s boundaries to be smoothed out and filled in for better presentation by tick the box of Nc.
4. Input Weight Grid
   • If the user wants to cover the streamlined and contributing catchments that are not typically included because they are too little to merge into the mainstream, they can tick the box of Input Weight Grid.
5. Then click ‘OK’

Note: The colors on the watershed generated in the software is only representing the different catchments in the project

User can also view the watershed in 3D by going to Main > then click 3D view

For visual tutorial, user may refer to video below;

For further reference, user may refer to the blog post below;

Watershed Delineation Guideline

Watershed Analysis

Watershed Case Study