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NHDPlusV1 Tools

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Table of Contents


NHDPlus Append Tool

Append combines individual NHDPlus workspaces to form larger NHDPlus workspaces. Generally, Append is used to combine NHDPlus HUC8 workspaces. While there is no absolute limit to the size of appended NHDPlus workspaces, there are some yet-to-be-quantified software limits and some usability limits. Note: The NHDPlus HUC8 workspaces are currently available for download at HUC8 Data Extensions.

System Requirements: Windows XP, Service Pack 2; Microsoft .Net 2.0 Framework (installed BEFORE ArcGIS); ArcGIS 9.2 (ArcInfo license level), Service Pack 4 or higher; ArcGIS Spatial Analyst License

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NHDPlus Aquatic Exposure Tool (AquaXpos)

AquaXpos conducts a geospatial analysis of the NHDPlus stream network to identify potential pesticide use impacts. Based on an initial area of concern and a method for estimating pesticide impact, AquaXpos analyzes the stream network to find places, downstream from potential pesticide use sites, where chemical impact's may exceed a specific level of concern.

The AquaXpos User Guide (PDF) (4 pp, 73.4 K, About PDF) Exit

System Requirements: Windows XP, Service Pack 2; Microsoft .Net 2.0 Framework

AquaXpos, Basin Delineator, and CA3T require the installation of the NHDPlus Tools Application Data which may be installed by downloading and running the following self-extracting exe:

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NHDPlus Basin Delineator Tool (BasinDelineator)

The NHDPlus BasinDelineator will delineate drainage basins for a user-defined set of basin pourpoints. The input pourpoints may be specified in one of two ways. First, by a basin identifier, an NHD linear reachcode, and a measure along the reach. Second, by a basin identifier, and latitude/longitude point. The pourpoints must be located on the NHDPlus network which is defined as the subset of NHD flowlines with known flow direction (i.e. NHDFLowline.Flowdir = "With Digitized"). The BasinDelineator returns a shapefile which contains a basin polygon for each correctly specified basin pourpoint.

Note: When installing the NHDPlus Basin Delineator, execute BasinDelineatorSetup.exe, not the BasinDelineatorinstall.msi.

The BasinDelineator User Guide (PDF)(6 pp, 49.5 K) Exit

System Requirements: Windows XP, Service Pack 2; Microsoft .Net 2.0 Framework (installed BEFORE ArcGIS); ArcGIS 9.3.1 (ArcInfo license level), Service Pack 2 or higher; ArcGIS Spatial Analyst License

AquaXpos, Basin Delineator, and CA3T require the installation of the NHDPlus Tools Application Data which may be installed by downloading and running the following self-extracting exe:

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NHDPlus Catchment Attribute Allocation and Accumulation Tool (CA3T)

CA3T has two functions, an attribute allocation function and an attribute accumulation function, which may be used separately or in combination. The CA3T allocation function takes a user-supplied grid format dataset of one or more landscape attributes and allocates the attributes to the NHDPlus catchments. The CA3T accumulation function builds, for each NHDPlus Flowline, the total upstream accumulated values for attributes that have been allocated to either NHDPlus catchments or NHDPlus flowlines.

The CA3T User Guide (PDF)(9 pp, 170 K). Exit

System Requirements: Windows XP, Service Pack 2; Microsoft .Net 2.0 Framework (installed BEFORE ArcGIS); ArcGIS 9.2 (ArcInfo license level), Service Pack 4 or higher; ArcGIS Spatial Analyst License

AquaXpos, Basin Delineator, and CA3T require the installation of the NHDPlus Tools Application Data which may be installed by downloading and running the following self-extracting exe:

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NHDPlus VAA COM Object Navigator Tool

The VAA COM Object Navigator uses the NHDPlus value added attributes to perform four types of navigations: upstream main stem, upstream with tributaries, downstream main stem, and downstream with divergences. Any of the four types of navigation may be stopped at a user-supplied distance from the starting point. This navigator may be used through ArcMap via a special ArcMap Toolbar or it may be called from user-written program code. The navigator will work on any NHDGEOinSHP dataset that contains a fully populated NHDFlowlineVAA.dbf table (generally this means an NHDPlus dataset). When used via the ArcMap toolbar, results are returned to ArcMap as a new layer in the map called Navigation Results. When used outside of ArcMap, results are returned in a table called tblNavResults in the TNavWork.mdb database which resides in the highest level directory of the NHDPlus dataset. This navigator is a COM object and may be call from user-written code that is developed in a COM-compliant programming language.

System Requirements: Windows XP, Service Pack 2; Microsoft .Net 2.0 Framework (installed BEFORE ArcGIS); ArcGIS 9.2, Service Pack 4 or higher

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NHDPlus Flow Table Navigator Tool

The Flow Table Navigator uses the NHDFlow table to walk the network from one network feature to the next. The navigator performs four types of navigations: upstream main stem, upstream with tributaries, downstream main stem, downstream with divergences. It may be used through ArcMap via a special ArcMap Toolbar or it may be called from user-written program code. The navigator will work on any NHDGEOinSHP dataset, including NHDPlus, that contains a fully populated NHDFlow.dbf table. Results are returned to ArcMap as a selected set of the NHDFlowline layer. When used outside of ArcMap, results are returned in a text file residing in the highest level directory of the NHDPlus dataset.

System Requirements: Windows XP, Service Pack 2; ArcGIS 9.2, Service Pack 4 or higher

  • NHDPlus Flow Table Navigator, Version 1.00 (ZIP)(371 K) Exit

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    NHDPlus User Toolbox

    The NHDPlus User Toolbox contains a tool called NHD QAQC. The NHD QAQC utility performs a series of flowline network qaqc checks on NHDGeo data in either pgdb format or Shapefile format. The qaqc checks validate the internal consistency of the NHDFlow table and insure that the NHDFlowline Geometry is in agreement with the NHDFlow table. In addition, there are qaqc checks that determine whether named watercourses and flowline reaches are linear and continuous. Each qaqc check is classified as severe or warning level. All severe checks must be corrected in order for the NHD data to be used in the NHDPlus Build process.

    If you would like a copy of the NHDPlus User Toolbox, please send your request to NHDPlus Support (dewald.tommy@epa.gov).

    System Requirements: Windows XP, Service Pack 2; ArcGIS 9.2, Service Pack 4 or higher, SQL Server 2005 Express

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