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Snap Pour Point (Spatial Analyst Tools)

Summary

Snaps pour points to the cell of highest flow accumulation within a specified distance.

Usage

  • The Snap Pour Point tool is used to ensure the selection of points of high accumulated flow when delineating drainage basins using the Watershed tool. Snap Pour Point will search within a snap distance around the specified pour points for the cell of highest accumulated flow and move the pour point to that location.

  • If the input pour point data is a point feature class, it will be converted to a raster internally for processing.

  • The output is an integer raster when the original pour point locations have been snapped to locations of higher accumulated flow.

  • When there is only one input pour point location, the extent of the output is that of the accumulation raster. If there is more than one pour point location, the extent of the output is determined by the settings in the Extent environment.

  • If more than one input pour point is snapped to the same location, only the last pour point snapped to that location will be retained in the output raster.

  • When specifying the input pour point locations as feature data, the default field will be the first available valid field. If no valid field exists, the ObjectID field (for example, OID or FID) will be the default.

  • When the output raster format is .crf, this tool supports the Pyramid raster storage environment. Pyramids will be created in the output by default. For any other output format, this environment is not supported, and pyramids will not be created.

  • See Analysis environments and Spatial Analyst for additional details on the geoprocessing environments that apply to this tool.

Parameters

Label Explanation Data type

Input raster or feature pour point data

The input pour point locations that will be snapped.

For a raster input, all cells that are not NoData (that is, have a value) will be considered pour points and will be snapped.

For a point feature input, this specifies the locations of cells that will be snapped.

Raster Layer; Feature Layer

Input accumulation raster

The input flow accumulation raster.

This can be created with the Flow Accumulation tool.

Raster Layer

Snap distance

The maximum distance, in map units, that will be searched for a cell of higher accumulated flow.

Double

Pour point field

(Optional)

The field used to assign values to the pour point locations.

If the pour point dataset is a raster, use Value.

If the pour point dataset is a feature, use a numeric field. If the field contains floating-point values, they will be truncated into integers.

Field

Return value

Label Explanation Data type

Output raster

The output pour point raster where the original pour point locations have been snapped to locations of higher accumulated flow.

This output is of integer type.

Raster

Environments

Auto Commit, Cell Size, Cell Size Projection Method, Compression, Current Workspace, Extent, Geographic Transformations, Mask, Output CONFIG Keyword, Output Coordinate System, Pyramid, Scratch Workspace, Snap Raster, Tile Size

Licensing information

  • Basic: Requires Spatial Analyst
  • Standard: Requires Spatial Analyst
  • Advanced: Requires Spatial Analyst