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.
- Author: V. Wichmann (c) 2022
- Menu: Terrain Analysis|Hydrology|Miscellaneous
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | DEM | Grid, input | DEM | The digital elevation model to flood. | - |
| Seed Points | Shapes, input | SEEDS | The point(s) from where to start the flooding. | - |
| Output | Water Body | Grid, output | WATER_BODY | The extent of the water body, labeled with local water depth [map units]. | - |
| Flooded DEM (*) | Grid, output, optional | DEM_FLOODED | The flooded digital elevation model. | - |
| Options | Grid System | Grid system | PARAMETERS_GRID_SYSTEM | - | - |
| Water Level (*) | Table field | WATER_LEVEL | The attribute field with the local water level, given either relative to the DEM or as absolute height [map units]. | - |
| Default | Floating point | WATER_LEVEL_DEFAULT | default value if no attribute has been selected | Default: 0.500000 |
| Water Level Reference | Choice | LEVEL_REFERENCE | - | Available Choices:
[0] level is given relative to DEM
[1] level is given as absolute water height
Default: 0 |
| Constant Water Level | Boolean | CONSTANT_LEVEL | Model 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