Calculate Pour Point
Feature Description
The Calculate Pour Point feature generates pour point raster data based on flow direction raster and accumulated flow data.
- Pour points are located at the boundaries of watersheds, typically at the lowest points along these boundaries. As water flows out of watersheds through pour points, they must have high accumulated flow values. This characteristic allows pour point extraction using flow direction and accumulated flow data.
- Determining pour points requires a flow accumulation threshold. Grid cells with accumulated flow values greater than or equal to this threshold are considered potential pour points, which are then finalized based on flow direction. The threshold selection critically affects the quantity/location of pour points and the size/range of sub-watersheds. Determining a reasonable threshold requires consideration of soil characteristics, slope features, climate conditions, and actual research needs, making it a challenging task.
- The generated pour point raster can be combined with flow direction data for watershed segmentation.
Parameter Description
| Parameter | Default | Description | Type |
|---|---|---|---|
| Flow Direction Data | Specifies the datasource and dataset containing flow direction raster | DatasetGrid | |
| Accumulated Flow Data | Specifies the datasource and dataset containing accumulated flow raster | DatasetGrid | |
| Threshold | 0 | Defines the extraction threshold. Only cells with accumulated flow values exceeding this threshold will be extracted as pour points. | Integer |
| Target Datasource | Specifies the datasource to store the result dataset | Datasource | |
| Result Dataset Name | Specifies the name of the result dataset | String |
Output
| Parameter | Description | Type |
|---|---|---|
| Result Pour Point Raster Data | The generated pour point raster dataset | DatasetGrid |