Sub-catchments

Sub-catchments

Sub-catchments describe the areas draining to a pit or other kind of node. Their main characteristics are their size, the type of land-use that occupies the area, and the time that it takes for runoff to concentrate at the catchment outlet.

Different hydrological models, such as the Horton (ILSAX), rational method and RAFTS models, employ different parameters, and will require different information.

Following a run, peak flowrates are presented in the Main Window as a black number.

If multiple storms are used, the results for a particular storm can be selected from the pull-down menu that appears in the top-left corner of the Window. The Customise Text option in the View menu allows you to vary the on-screen display.

Flows from sub-catchments can be examined using the Pop-Up (right mouse button) menu that provides options for viewing numerical run results as graphs or tables. For example, hydrographs calculated during a run with an Horton (ILSAX) model can be chosen for the menu below.



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