Catchments and subcatchment outlets can be assigned by:

 

•manually drawing lines on the screen (Subcatchments >> Draw Outlet)

•importing a GIS file of subcatchment boundaries (Subcatchments >> Import Outlets)

•using flat or pit pixels (i.e., depression areas) (Subcatchments >> Other >> Add Flats and Pits as Outlets)

•using ocean coastline (Subcatchments >> Other >> Add Ocean Coastline as Outlet)

•using lakes or other water bodies (Subcatchments >> Add Lakes)

•using CatchmentSIM streams (Subcatchments >> Add Stream), or

•first mapping a catchment and then using an automated catchment break-up algorithm (Subcatchments >> Breakup Subcatchment).

 

Following assignment of a catchment and / or subcatchment boundaries, the flow mapping algorithm can be applied (Subcatchments >> Map All) to map subcatchment boundaries. Flow paths from individual pixels can be illustrated using Flow Mapping >> Map Pixel Flow Path. The flow mapping algorithm is described in the following sections.