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Drainage Area Characterization

Description

The Drainage Area Characterization tool (Terrain Morphology) generates elevation, area and volume curves for a set of selected drainage areas. The function divides each drainage area into slices and calculates each slice’s elevation characteristics, as well as the cumulative area and volume that are below the elevation of the top of the slice. These characteristics are stored in an output Drainage EAV table. The function works with a selected set of drainage areas or with all drainage areas within the input feature class if there is no selected set.

When a strictly positive extrusion value is specified, one additional slice will be created.

Usage

Parameters

Direction Type Parameter Name Data Type Dialog Reference
Input Required Input Drainage Area Feature Class GPFeatureLayer Input drainage area features to process. Required field: HydroIDFields created:
  • MinElev: Minimum elevation for the drainage area in XY unit
  • MaxElev: Maximum elevation for the drainage area in XY unit
  • IsPitted: created empty. Indicates whether the drainage area contains a pit (1). Required by the functions Drainage Boundary Characterization and Drainage Connectivity Characterization.
  • IsDone: Indicates whether the drainage area was successfully processed (1) or not (-1).
    		•
    Input Required Input DEM Raster GPRasterLayer Input DEM.
    Input Required Characterization Type GPString Type of characterization performed:
  • Slice_Count
  • Slice_Increment
  • Boundary_MinZ
  • TwoDeltaH
    		•
    Input Required Characterization Type Parameters GPString Characterization parameter associated to the type of characterization performed:
  • Slice_Count: number of slices
  • Slice_Increment: increment for each slice
  • Boundary_MinZ:
  • TwoDeltaH
    		•
    Input Required Extrusion (linear units) GPDouble Input extrusion value used to create one additional slice (optional).
    Output Required Output Drainage EAV Table GPTableView Output elevation-area-volume table characterizing the slices. Fields created:
  • FeatureID: HydroID of the corresponding drainage area
  • BottomElev: Bottom elevation of the slice in XY unit
  • TopElev: Top elevation of the slice in XY unit
  • SlcElev: Middle elevation of the slice, i.e. (top + bottom)/2 in XY unit
  • CumArea: Area of the drainage area having an elevation that is less than or equal to the top elevation of the slice.
  • CumVolume: Volume of water needed to fill the drainage area up to the top elevation of the slice.
    		•
    Input Optional Input Exclusion Area Feature Class GPFeatureLayer Optional exclusion areas features defining the areas that will not be characterized.