SAGA-GIS Tool Library Documentation (v9.1.2)

Tool Terrain Flooding

The tool allows one to flood a digital elevation model for a given water level. The water level can be provided either as absolute height or relative to the DEM.
If the water level is given relative to the DEM, the tool can model a constant water level starting from the seed cell, or a water level that is always relative to the currently processed cell. This way also inclined water surfaces, e.g. along a river, can be modelled. Note that this usually requires rather small relative water levels in order to prevent the flooding of the complete DEM; the functionality is most suited to generate a segment (connected component) of a river bed.

Parameters

 NameTypeIdentifierDescriptionConstraints
InputDEMGrid, inputDEMThe digital elevation model to flood.-
Seed PointsShapes, inputSEEDSThe point(s) from where to start the flooding.-
OutputWater BodyGrid, outputWATER_BODYThe extent of the water body, labeled with local water depth [map units].-
Flooded DEM (*)Grid, output, optionalDEM_FLOODEDThe flooded digital elevation model.-
OptionsGrid SystemGrid systemPARAMETERS_GRID_SYSTEM--
Water Level (*)Table fieldWATER_LEVELThe attribute field with the local water level, given either relative to the DEM or as absolute height [map units].-
DefaultFloating pointWATER_LEVEL_DEFAULTdefault value if no attribute has been selectedDefault: 0.500000
Water Level ReferenceChoiceLEVEL_REFERENCE-Available Choices:
[0] level is given relative to DEM
[1] level is given as absolute water height
Default: 0
Constant Water LevelBooleanCONSTANT_LEVELModel the water level as constant. Otherwise the specified level is always taken as relative to the currently processed cell. This option is only available if the water level reference is relative to the DEM.Default: 1
(*) optional

Command-line

Usage: saga_cmd ta_hydrology 32 [-DEM <str>] [-SEEDS <str>] [-WATER_LEVEL <str>] [-WATER_LEVEL_DEFAULT <double>] [-LEVEL_REFERENCE <str>] [-CONSTANT_LEVEL <str>] [-WATER_BODY <str>] [-DEM_FLOODED <str>]
  -DEM:<str>                   	DEM
	Grid, input
  -SEEDS:<str>                 	Seed Points
	Shapes, input
  -WATER_LEVEL:<str>           	Water Level
	Table field
  -WATER_LEVEL_DEFAULT:<double>	Default
	Floating point
	Default: 0.500000
  -LEVEL_REFERENCE:<str>       	Water Level Reference
	Choice
	Available Choices:
	[0] level is given relative to DEM
	[1] level is given as absolute water height
	Default: 0
  -CONSTANT_LEVEL:<str>        	Constant Water Level
	Boolean
	Default: 1
  -WATER_BODY:<str>            	Water Body
	Grid, output
  -DEM_FLOODED:<str>           	Flooded DEM
	Grid, output, optional