1Select final HRUs
Users can create single or multiple HRUs per subbasin.
Dominant landuse, soil slope
This option creates single HRU for each subbasin. For each subbasin, dominant land use, soil and slope class are simulated.
Dominant HRU
This option creates single HRU for each subbasin. For each subbasin, land use, soil and slope class from the dominant HRU are simulated.
Filter by landuse, soil, slope
This option creates multiple HRUs for subbasins. For this option, users need to define what percentage of landuse, soil and slope are to be used in selecting subbasins. Any HRU that falls below the threshold landuse or soil or slope is not selected as final HRU. Use the slider to change the threshold percent for landuse, soil and slope or enter new values on the respective text box.
Filter by area
This option creates multiple HRUs for subbasins. For this option users need to define the threshold and select whether the threshold is based on area or percentage of HRU area within subbasin. Any HRU that is below the target area or target percentage area of the subbasin is not selected as the final HRU. Select either percentage of subbasin or area.
Use the slider to change the threshold or manually enter a new threshold in the provided textbox.
Target number of HRUs
This option creates multiple HRUs for subbasins. For this option users need to select the threshold method and the target number of HRUs. Threshold method can be either percent of subbasin or area. Based on the selected method, HRUs with highest area or percent of subbasin area are selected until target number of HRUs are reached. This method makes sure that each subbasin contains at least one HRU.
Select threshold method. Set target number of HRUs by sliding the scroll bar or entering a value in the text box. Once HRU selection method is selected, click ‘Finalize HRUs’. HRUs are selected and final number of subbasins and number of HRUs.
Click OK. A new interface appears as shown below.
2Download topographic and HRU files
Select topographic, land use, soil and slope description files to download. a. Select ‘Topographic report’ for a statistical summary and distribution of discrete land surface elevations in the watershed and all the sub watersheds. b. Select ‘Landuse, soil, slope report’ for a detailed description of the distribution of the land use, soil and slope classes in the watershed, and all the sub-watersheds. c. Select ‘HRU, landuse, soil, slope report’ for a detailed description of the distribution of the land use, soil, and slope classes. The number of HRUs with the land use, soil, slope classes and aerial extent are listed for each subbasin. d. Click ‘Download’. The files are zipped and downloaded.
3Write SwaNET input files
The final step in SwaNET project creation is to write SWAT input files.
a. Select weather generator file. If the watershed is outside the US, select ‘WGEN_CFSR_World’. For the US, select any of the available weather generator file from the list. b. To add dummy point source inputs for subbasins, check ‘Add dummy point source files to subbasins’. These files can be updated later from the SwaNET interface. c. To add dummy reservoir inputs for subbasins, check ‘Add dummy reservoir files to subbasins’. These files can be updated later from the SwaNET interface. d. For test running SwaNET, check ‘Test run SwaNET’. e. Click ‘Write input files’. SWAT input files are created and a prompt appears indicating that the process is complete.
Click OK. Another prompt appears asking whether to load a SwaNET project. Click OK.
Click OK. SwaNET project creation process is complete. You can now run the SwaNET model.
