Split NHDPlus HR Processing Unit

Description

Splits input NHDPlus HR data into processing units defined in the selected set of features in the "Input Split Polygon Layer".

Usage

Splits input NHDPlus HR data into processing units defined in the selected set of features in the "Input Split Polygon Layer". Note that you have to select at least one polygon feature for the tool to operate, and the input data must be in the default data structure of NHDPlus HR data downloads. For each selected polygon, a folder is created in the target folder with the name defined in the "Input Name Field" for the polygon. The split data will be projected into the target spatial reference.

The extracted content will depend on the selected extraction options ("Extract Advanced NHDPlus HR Content" and "Extract NHDPlus HR Content for NWM Forecast Integration"). By default, the DEM is always extracted and converted into a floating point raster with vertical units of meters.

• If "Extract Advanced NHDPlus HR Content" is checked, the following is exported:
  • Flow Direction
  • Flow Accumulation
  • NHDPlusBurnLineEvent
  • NHDPlusBurnWaterbody
  • NHDFlowlineNHDPlusCatchment
• If "Extract NHDPLus HR Content for NWM Forecast Integration" is checked, the following is exported:
  • Flow Direction
  • Flow Accumulation
  • NHDPlusBurnLineEvent
  • NHDPlusBurnWaterbody
  • NHDFlowlineNHDPlusCatchment

Parameters

Parameter Name	Type	Direction	Data Type	Dialog Reference
Input HUC4 NHDPlus HR Integer DEM Raster	Required	Input	Raster Layer	Input integer DEM contained within the NHDPlus HR download folder package.
Input Split Polygon Layer	Required	Input	Feature Layer	Polygon feature class contained within the NHDPlus HR download folder package that represents the polygons to be used to create processing unit split data. Typically, that will be HUC watersheds boundaries of different level. Normally, a HUC6 or HUC8 level boundaries are used. NHDPlus HR geodatabase contains WBD boundaries in the WBD dataset that can be used for this purpose (e.g., WBDHU6 or WBDHU8). At least one polygon should be selected, otherwise all polygons will be processed.
Input Name Field	Required	Input	Field	Field name in the input split polygon layer that will be used to name the split folder and geodatabase. The content of that field for each selected polygon will be prefixed by "H" to produce the name of the folder and gdb. When using NHDPlus HR WBDHU6 or WBDHU8 as split polygon layer, those fields will be HUC6 or HUC8 respectively.
Target Folder	Required	Input	Folder	Path to the parent folder in which all processing unit folders will be placed.
Target Spatial Reference	Optional	Input	Spatial Reference	Spatial reference of the output processing unit extracted data, including BOTH the target projected coordinate system and the target vertical coordinate system. The vertical coordinate system must be in units of meters. If no spatial reference is provided, the spatial reference of the input layers will be used. The output elevation raster in meters will have the default vertical coordinate system edited to set the linear units to meters.
Extract Advanced NHDPlus HR Content	Optional	Input	Boolean	If this option is checked, additional NHDPlus HR layers will be extracted and placed in the processing unit folder and geodatabase.
Extract NHDPlus HR Content for NWM Forecast Integration	Optional	Input	Boolean	If this option is checked, additional NHDPlus HR layers needed to support NWM flow forecast integration will be extracted and placed in the processing unit folder and geodatabase.
Input NWM Channel Layer	Optional	Input	Feature Layer	Optional input NWM channel layer to extract for NWM forecast integration.
Input NWM Catchment Layer	Optional	Input	Feature Layer	Optional input NWM catchment layer to extract for NWM forecast integration.
Input NWM Lake Layer	Optional	Input	Feature Layer	Optional input NWM lake layer to extract for NWM forecast integration.
Input NWM Point Layer	Optional	Input	Feature Layer	Optional input NWM forecast point layer to extract for NWM forecast integration.
Input NWM Point Channel Layer	Optional	Input	Feature Layer	Optional input NWM point channel layer to extract for NWM forecast integration.
Input Draft Deranged Polygon Layer	Optional	Input	Feature Layer	Optional input NWM deranged polygon layer to extract for NWM forecast integration.

Code Sample

import splitnhdplushrprocessingunit

p = splitnhdplushrprocessingunit.SplitNHDPlusHRProcessingUnit()
p.DebugLevel = 1
t_returns = p_classop.executeAH(Input_Integer_DEM_Raster, Input_HUC6_Layer, Input_HUC_Naming_Field, Input_Target_Folder, Input_Target_Spref, Bool_Advanced_Content, Bool_NWM_Forecast_Content, Opt_NWM_Channel_Layer, Opt_NWM_Catchment_Layer, Opt_NWM_Lake_Layer, Opt_NWM_Point_Layer, Opt_NWM_Point_Channel_Layer, "..")    
print(t_returns[0])