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Drainage Area Centroid

Description

Calculate the centroid point of each input drainage area (labeled by the HydroID), using one of three methods: center of gravity, halfway distance along the longest flowpath, or where 50% of the drainage area flows to along the given flowpath. Output the centroid(s) to a new feature class.

Usage

Using one of three calculation methods, a centroid point feature is created for each drainage area in the input feature layer. Multiple drainage areas should have unique HydroIDs. This tool will populate the JunctionID for each centroid if JunctionIDs have already been populated for the input drainage area.

Parameters

Parameter Name	Type	Direction	Data Type	Dialog Reference
Input Drainage Area	Required	Input	Feature Layer	Input catchment or subwatershed feature layer. The input feature layer must have HydroIDs assigned for multiple drainage areas. If JunctionIDs are also populated for the feature layer, the output centroid feature class will include them.
Select Centroid Method	Required	Input	String	Select a method for calculating the centroid. Option "Center of gravity" will use the polygon geometry to calculate the centroid. Option "Longest flowpath" will calculate the centroid to be halfway along the longest flow path. Option "Fifty percent area" will calculate the centroid to be where 50% of flow accumulation is received along a given river line.
Output Centroid	Required	Output	Feature Layer	Output point feature layer that store the calculated centroid(s) that correspond to each HydroID.
Input Flow Path (polyline)	Optional	Input	Feature Class	Input flow path feature needed for calculation options: "Longest flowpath" and "Fifty percent area." Flowlines should each have DrainIDs that correspond to basin HydroIDs.
Input Flow Accumulation Raster	Optional	Input	Raster Layer	Input flow accumulation raster needed for calculation options: "Fifty percent area".
Populate HydroID	Optional	Input	Boolean	Select True or False for generating a HydroID per output centroid. If True. existing HydroIDs are overwritten. Default = False.