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Connecticut Watershed Boundary Dataset Poly

Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator: U.S. Department of Agriculture, Natural Resources Conservation Service
Publication_Date: 2001
Title:
Connecticut Watershed Boundary Dataset Poly
Geospatial_Data_Presentation_Form: vector digital data
Publication_Information:
Publication_Place: Fort Worth, TX
Publisher: U.S. Department of Agriculture, Natural Resources Conservation Service
Other_Citation_Details:
Initially entitled ct_hu12_geo83, this dataset was renamed NRCS Watershed Boundary Dataset Poly when it was converted to the Connecticut State Plane Coordinate System (NAD 83) for use by the State of Connecticut, Department of Environmental Protection in 2005.
Online_Linkage: http://www.lighthouse.nrcs.usda.gov/gateway/gatewayhome.html
Description:
Abstract:
This data set is a digital hydrologic unit boundary layer that is at the Subwatershed (12-digit) level. The original data set was developed by delineating the boundary lines on base USGS 1:24000 scale topographic quadrangle, and digitizing the delineated lines. Digital Raster Graphics (DRG) images were used for edits to the data layer. 

This data set consists of geo-referenced digital map data and attribute data. The spatial data are in a statewide coverage format and include complete coverage of the entire state of Connecticut, and small parts of surrounding states. The hydrologic unit ID code attached to each delineated polygon is linked to the attribute data.
Purpose:
The Watershed and Subwatershed hydrologic unit boundaries provide a uniquely identified and uniform method of subdividing large drainage areas. These smaller sized hydrologic units (up to 250,000 acres) are useful in many programs supported by the Natural Resources Conservation Service and others.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2001
Currentness_Reference:
publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -73.737982
East_Bounding_Coordinate: -71.646339
North_Bounding_Coordinate: 42.233967
South_Bounding_Coordinate: 40.939104
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Hydrologic Units
Theme_Keyword: Watershed Boundary Dataset
Theme_Keyword: Subwatersheds
Theme_Keyword: WBD
Theme_Keyword: Watersheds
Place:
Place_Keyword_Thesaurus: Counties and County Equivalents of the States of the United States and the
Place_Keyword: New England
Place_Keyword: Connecticut
Place:
Place_Keyword_Thesaurus: USGS Topographic Map Names Data Base
Place_Keyword: Northeastern United States
Access_Constraints: None
Use_Constraints:
The U.S. Department of Agriculture, Natural Resources Conservation Service, should be acknowledged as the data source in products derived from these data. 

This data set is to be used as a primary reference source. This is public information and may be interpreted by organizations, agencies, units of government, or others based on needs; however, they are responsible for the appropriate application. Federal, State, or local regulatory bodies are not to reassign to the Natural Resources Conservation Service any authority for the decisions they make. 

Photographic or digital enlargement of these maps to scales greater than that at which they were originally delineated can cause misrepresentation of the data. If enlarged, the maps will not include the fine detail that would be appropriate for mapping at the small scale. Digital data files are periodically updated. Files are dated, and users are responsible for obtaining the latest version of the data.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Department of Agriculture, Natural Resources Conservation Service
Contact_Position: GIS Specialist
Contact_Address:
Address_Type: mailing address
Address:
344 Merrow Road
City: Tolland
State_or_Province: Connecticut
Postal_Code: 06084-3917
Country: USA
Contact_Voice_Telephone: 860-871-4011
Contact_TDD/TTY_Telephone: 202 720 7808 (Office of Public Affairs)
Contact_Facsimile_Telephone: 860-871-4054
Browse_Graphic:
Browse_Graphic_File_Name: http://www.cteco.uconn.edu/metadata/dep/browsegraphic/watershedboundarydatasetfullview.gif
Browse_Graphic_File_Description:
Full view of Connecticut Watershed Boundary Dataset polygon and line features.
Browse_Graphic_File_Type: GIF
Browse_Graphic:
Browse_Graphic_File_Name: http://www.cteco.uconn.edu/metadata/dep/browsegraphic/watershedboundarydatasetdetailviewhuc12.gif
Browse_Graphic_File_Description:
Detailed view of Connecticut Watershed Boundary Dataset polygon and line features. Watersheds are labeled with the 12-digit Hydrologic Unit Code (HUC12).
Browse_Graphic_File_Type: GIF
Browse_Graphic:
Browse_Graphic_File_Name: http://www.cteco.uconn.edu/metadata/dep/browsegraphic/watershedboundarydatasetdetailviewhuc10.gif
Browse_Graphic_File_Description:
Detailed view of Connecticut Watershed Boundary Dataset polygon and line features. Watersheds are labeled with the 10-digit Hydrologic Unit Code (HUC10).
Browse_Graphic_File_Type: GIF
Browse_Graphic:
Browse_Graphic_File_Name: http://www.cteco.uconn.edu/metadata/dep/browsegraphic/watershedboundarydatasetdetailviewhuc8.gif
Browse_Graphic_File_Description:
Detailed view of Connecticut Watershed Boundary Dataset polygon and line features. Watersheds are labeled with the 8-digit Hydrologic Unit Code (HUC8).
Browse_Graphic_File_Type: GIF
Native_Data_Set_Environment:
These data are maintained by the State of Connecticut using ArcGIS software developed by Environmental Systems Research Institute (ESRI) in a Microsoft Windows operating system environment.
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Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
Polygon identifiers are visually checked with the DRG backdrop and compared with other available information, such as tables of basins with their codes.
Logical_Consistency_Report:
Certain node/geometry and topology (GT) polygon/chain relationships are collected or generated to satisfy topological requirements. (The GT-polygon corresponds to a hydrologic unit or a portion of a hydrologic unit at the edge of a quadrangle sheet.) Some of these requirements include: chains must begin and end at nodes, left and right GT-polygons are defined for each chain element and are consistent throughout. The tests of logical consistency are performed using vendor software. All internal polygons are tested for closure with vendor software.  All data are checked for common boundary lines (i.e., adjacent polygons with the same label).
Completeness_Report:
Subwatershed and Watershed naming conventions  differ from the newest standard specifications by being more descriptive of the stream reach which the hydrologic unit encompasses.  This was done to minimize confusion in areas where tributary stream names are similar.  Other attributes have been added to further clarify location within New England.  Subwatershed boundaries were delineated outside the state border in order to complete hydrologic units which straddled the border.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The accuracy of these maps is generally based on the contour information of corresponding DRGs. The differences in positional accuracy between the hydrologic unit boundaries and their digitized map locations is unknown. 

Hydrologic unit boundaries generally were digitized within 0.01 inches of their locations on the digitizing source.  Edge match locations are exact because the data were extracted from a New England-based hydrologic units layer which had been electronically edge-matched.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: USDA-Natural Resources Conservation Service
Publication_Date: 2001
Title:
Subwatersheds for Connecticut
Geospatial_Data_Presentation_Form: Statewide coverage
Publication_Information:
Publication_Place: Tolland, Connecticut, USA
Publisher: Natural Resources Conservation Service
Source_Scale_Denominator: 24000
Type_of_Source_Media: paper; USGS Digital Raster Graphics
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 1969
Ending_Date: 1984
Source_Currentness_Reference:
varies
Source_Citation_Abbreviation:
NRCS
Source_Contribution:
map delineation
Process_Step:
Process_Description:
Map delineation on paper topographic quads.
Source_Used_Citation_Abbreviation:
CT DEP
Process_Date: Unknown
Process_Step:
Process_Description:
Map digitizing
Source_Used_Citation_Abbreviation:
CT DEP
Process_Date: Unknown
Process_Step:
Process_Description:
Digitizing begins on NRCS Subwatersheds layer
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 1997
Process_Step:
Process_Description:
Data layer attribution, editing, review by CT NRCS and DEP personnel, USGS
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 1997
Process_Step:
Process_Description:
Delineation of New York hydrologic unit boundaries for units that cross border
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 1998
Process_Step:
Process_Description:
Edge match with Massachusetts: both arcs and attributes
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 1999
Process_Step:
Process_Description:
Edge match with available New York data (watershed level only), including digitizing of new hydrologic unit boundaries where necessary to complete all polygons which straddle state border.
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 1999
Process_Step:
Process_Description:
Edge match with Rhode Island: both arcs and attributes
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 2000
Process_Step:
Process_Description:
Review and editing/combining of smaller subwatersheds to better meet National Standard
Source_Used_Citation_Abbreviation:
NRCS, DEP
Process_Date: 2000
Process_Step:
Process_Description:
Attribute edits to update layer to newest Hydrologic Unit Digitizing Standard
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 2001
Process_Step:
Process_Description:
Metadata creation
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 2001
Process_Step:
Process_Description:
Reprojection to UTM NAD83
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 2001
Process_Step:
Process_Description:
Submission for National Review and Certification
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 2001
Process_Step:
Process_Description:
Conversion to Connecticut State Plane Coordinate System - Using ArcGIS 9.1 software, the polygon feature shapefile component to the Watershed Boundary Dataset for Connecticut (ct_hu12_geo83.shp) obtained from the NRCS ftp site was projected from geographic coordinates to the Connecticut State Plane Coordinate System of 1983 (NAD83) and named Watershed_Boundary_Dataset_Poly.shp. Where necessary, excluded the AREA and PERIMETER attributes from both the Shapefile and Attribute Entity portion of the metadata because these attributes are only maintained by ArcInfo software with data in ArcInfo Coverage format. Also deleted line and node feature attribute definitions from the metadata prepared by NRCS because they do not describe polygon features. For cartographic purposes, made an ArcView 3 Legend file and ArcMap Layer file.
Source_Used_Citation_Abbreviation:
NRCS
Process_Date: 20051130
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: State of Connecticut, Department of Environmental Protection
Contact_Person: Howie Sternberg
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Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains
Point_and_Vector_Object_Count: 194
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Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: Lambert Conformal Conic
Lambert_Conformal_Conic:
Lambert Conformal Conic
Standard_Parallel: 41.200000
Standard_Parallel: 41.866667
Longitude_of_Central_Meridian: -72.750000
Latitude_of_Projection_Origin: 40.833333
False_Easting: 999999.999996
False_Northing: 499999.999998
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.000250
Ordinate_Resolution: 0.000250
Planar_Distance_Units: survey feet
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257222
Vertical_Coordinate_System_Definition:
Altitude_System_Definition:
Altitude_Datum_Name: North American Vertical Datum of 1988
Altitude_Resolution: unknown
Altitude_Distance_Units: meters
Altitude_Encoding_Method: Implicit coordinate
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Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: Connecticut Watershed Boundary Dataset Poly
Entity_Type_Definition:
Attribute field (item) names need to be spelled exactly as shown and in the order specified. Required attributes must be populated unless fields are optional, in those cases, leave the field blank. The attribute schema is illustrated for Environmental Systems Research Institute (ESRI) software1. If another software is being used other than ArcInfo or ArcView, please follow the ArcInfo format. For field width in ArcView, please create the fields according to the width specified under "Output" in the descriptions below. All the fields listed below are required in each state dataset, but, a state may add additional fields to their own dataset. If there are any questions, contact the National Cartography & Geospatial Center for assistance.
Entity_Type_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute:
Attribute_Label: HU_12_TYPE
Attribute_Definition:
Populate this field with the hydrologic unit type from the list provided that most closely identifies the subwatershed.   Use any of the one digit abbreviations in uppercase that is provided in the list.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: Shape
Attribute_Definition:
Feature geometry.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Coordinates defining the features.
Attribute:
Attribute_Label: HUC_8
Attribute_Definition:
A unique 8-digit code from the USGS map series "Hydrologic Unit Maps".  Use the existing code for the sub-basin where the subwatershed resides; do not change this code.  The same number should be used in every record that pertains to a subwatershed that resides within the same 8-digit sub-basin.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: HUC_10
Attribute_Definition:
This field provides a unique 10-digit code for each watershed.  Add two digits to the end of the existing 8-digit code, therefore resulting in a 10-digit number.  This same number should be used in every record that pertains to a subwatershed that resides within the same 10-digit watershed.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: HUC_12
Attribute_Definition:
This field provides a unique 12-digit code for each subwatershed.  Add two digits to the end of the existing 10-digit code, therefore creating a 12-digit number.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: ACRES
Attribute_Definition:
Area of subwatershed including non-contributing areas calculated to acres as a whole number, no decimals.  The "Acres" field needs to be calculated from the "Area" field.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: STATES
Attribute_Definition:
The "States" field needs to include the names of all state(s) that the subwatershed falls within.  Use the 2-digit postal abbreviation in upper case and sort the state(s) in alphabetical order.  If using more then one abbreviation, separate with a comma with no space after the comma.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: NCONTRB_A
Attribute_Definition:
Drainage areas that do not flow toward the outlet of any hydrologic unit are considered non-contributing.  If a non-contributing area is on the boundary between two or more hydrologic units, determine the low point along the non-contributing area boundary.  The non-contributing area should be associated with the hydrologic unit adjacent to the low point on the boundary. This attribute should be the total of the non-contributing areas within a hydrologic unit calculated in acres.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: HU_10_DS
Attribute_Definition:
Populate this field with the 10-digit code of the 5th level hydrologic unit that is receiving the majority of the flow from the watershed that the 6th level HU falls within.  Outlets created by ditching or other artificial drainage are not to be considered for this field.  If the 5th level HU empties directly to the ocean and not to another hydrologic unit, the word, "ocean", is used in this field.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: HU_10_NAME
Attribute_Definition:
This field is for officially recognized names only.  Populate this field by following the directions in subsection 6.3 "Watershed and Subwatershed Naming Protocol".  Populate this field with the identical name for all 6th level hydrologic units that fall within the same 10-digit HU. The name used to attribute the watershed should be used only once within a 4th level unit.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: HU_10_MOD
Attribute_Definition:
This field should identify any type of modifications to natural overland flow present in the 10-digit watershed.  In the attribute field, identify from most significant to least significant modification(s).  Use one or more of the following abbreviations in uppercase to identify your modification(s).  If using more then one abbreviation, separate with a comma with no space after the comma.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute_Value_Accuracy_Information:
Attribute:
Attribute_Label: HU_10_TYPE
Attribute_Definition:
Populate this field with the hydrologic unit type from the list provided that most closely identifies the watershed.   Use any of the one-digit abbreviations in uppercase that is provided in the list.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: HU_12_DS
Attribute_Definition:
Populate this field with the 12-digit code of the 6th level hydrologic unit that is receiving the majority of the flow from the subwatershed.  Outlets created by ditching or other artificial drainage are not to be considered for this field. If the 6th level HU empties directly to the ocean and not to another hydrologic unit, the word, "ocean", is used in this field.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: HU_12_MOD
Attribute_Definition:
This field should identify any type of modifications to natural overland flow present in the 12-digit subwatershed.  In the attribute field, identify from most significant to least significant modification(s).  Use one or more of the following abbreviations in uppercase to identify your modification(s).  If using more than one abbreviation, separate with a comma with no space after the comma.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: OBJECTID
Attribute_Definition:
Internal feature number.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: SHAPE
Attribute_Definition:
Feature geometry.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Coordinates defining the features.
Attribute:
Attribute_Label: HU_12_NAME
Attribute_Definition:
This field is for officially recognized names only.  Populate this field by following the directions in subsection 6.3 "Watershed and Subwatershed Naming Protocol".  The name used to attribute the subwatershed should be used only once within a 5th level unit.
Attribute_Definition_Source:
Federal Standards for Delineation of Hydrologic Unit Boundaries - FGDC Proposal, Version 1.0
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name: Federal Standards for Delineation of Hydrologic Unit Boundaries, FGDC Proposal, Version 1.0
Codeset_Source: Please refer to the Entity and Attribute Overview for valid values and definitions
Attribute:
Attribute_Label: SHAPE.area
Attribute:
Attribute_Label: SHAPE.len
Overview_Description:
Entity_and_Attribute_Overview:
Hydrologic Unit delineations are closed polygons that encompass all area draining toward the lowest point (called outlet) in the polygon. Because of nominal sizes for the different hydrologic unit levels (Watershed (40,000 to 250,000 acres) and Subwatershed (3,000 minimum, generally 10,000 to 40,000 acres)), some polygons do not include all areas up to the drainage divide but all areas to one or more other upstream hydrologic units. A unique hydrologic unit code is used to identify each
hydrologic unit. The Watershed hydrologic unit codes start with the 8-digit Subbasin (Cataloging Unit) number that contains the Watershed. Likewise the Subwatershed hydrologic unit codes start with the 10-digit Watershed number that contains the Subwatershed. 

A map unit symbol uniquely identifies each closed polygon. Each symbol is linked to a hydrologic unit code. The uniqueness of hydrologic unit codes while applying to hydrologic units does not carry over to polygons. Small islands offshore in coastal and lakeshore areas or in river deltas are given the same code as adjacent hydrologic units on the mainland.

Attribute data associated with a hydrologic unit code includes: 
non-contributing area (acres); 
names for each level of nesting (region, subregion, basin, subbasin, watershed and subwatershed);
codes for hydrologic units immediately downstream;
name of town where subwatershed outlet occurs;
information about type of subwatershed or watershed;
reference to human-caused modifications to stream flow within the watershed;
notes concerning delineation of hydrologic unit boundary.

Description of attributes by field from the Federal Standards for Delineation of Hydrologic Unit Boundaries
1) .pat attributes

Huc_8 : Eight Digit Hydrologic Unit Code - (REQUIRED)
A unique 8-digit code from the USGS map series "Hydrologic Unit Maps".  Use the existing code for the sub-basin where the subwatershed resides; do not change this code.  The same number should be used in every record that pertains to a subwatershed that resides within the same 8-digit sub-basin.Numbers were assigned in an upstream to downstream fashion. Where no downstream/upstream relationship could be determined numbers were assigned in a clockwise fashion.

Huc_10:	Ten Digit Hydrologic Unit Code - (REQUIRED)
This field provides a unique 10-digit code for each watershed.  Add two digits to the end of the existing 8-digit code, therefore resulting in a 10-digit number.  This same number should be used in every record that pertains to a subwatershed that resides within the same 10-digit watershed.Numbers were assigned in an upstream to downstream fashion. Where no downstream/upstream relationship could be determined numbers were assigned in a clockwise fashion. It should be noted that the polygons that cross into Idaho were numbered by Idaho and are not consistent with the above methods. Affected huc_8s include: 17040202, 17040204 and 17040104.

Huc_12:	Twelve Digit Hydrologic Unit Code - (REQUIRED)
This field provides a unique 12-digit code for each subwatershed.  Add two digits to the end of the existing 10-digit code, therefore creating a 12-digit number.Numbers were assigned in an upstream to downstream fashion. Where no downstream/upstream relationship could be determined numbers were assigned in a clockwise fashion. It should be noted that the polygons that cross into Idaho were numbered by Idaho and are not consistent with the above methods. Affected huc_8s include: 17040202, 17040204 and 17040104.

Acres: 	Acres - (REQUIRED)
Area of subwatershed including non-contributing areas calculated to acres as a whole number, no decimals.  The "Acres" field needs to be calculated from the "Area" field.

States: 	States - (REQUIRED)
The "States" field needs to include the names of all state(s) that the subwatershed falls within.  Use the 2-digit postal abbreviation in upper case and sort the state(s) in alphabetical order.  If using more then one abbreviation, separate with a comma with no space after the comma.

Ncontrb_a: Non-Contributing Area - (FIELD REQUIRED, ATTRIBUTES OPTIONAL)
Drainage areas that do not flow toward the outlet of any hydrologic unit are considered non-contributing.  If a non-contributing area is on the boundary between two or more hydrologic units, determine the low point along the non-contributing area boundary.  The non-contributing area should be associated with the hydrologic unit adjacent to the low point on the boundary. This attribute should be the total of the non-contributing areas within a hydrologic unit calculated in acres.

Hu_10_ds: Fifth Level Downstream Hydrologic Unit Code - (FIELD REQUIRED, ATTRIBUTES OPTIONAL)
Populate this field with the 10-digit code of the 5th level hydrologic unit that is receiving the majority of the flow from the watershed that the 6th level HU falls within.  Outlets created by ditching or other artificial drainage are not to be considered for this field. If an HU flows into an ocean or the Gulf of Mexico populate this field with "OCEAN" and if a HU flows into one of the Great Lakes use the term "LAKE".  If a HU flows across international borders use "CANADA" or "MEXICO" depending on which country the HU drains into.  If an HU is  a closed basin, then populate this record with the term "CLOSED BASIN".

Hu_10_name: 	Fifth Level Hydrologic Unit Name - (FIELD REQUIRED, ATTRIBUTES OPTIONAL)
This field is for officially recognized names only.  Populate this field by following the directions in subsection 6.3 "Watershed and Subwatershed Naming Protocol".  Populate this field with the identical name for all 6th level hydrologic units that fall within the same 10-digit HU. The name used to attribute the watershed should be used only once within a 4th level unit. Some 10-digit HU were assigned the huc_10 number when no GNIS name was identified on the DRG-Es.

Hu_10_mod: 		Fifth Level Hydrologic Unit Modifications - (REQUIRED)
This field should identify any type of modifications to natural overland flow that alters the location of the hydrologic unit boundary for a 10-digit watershed.  In the attribute field, identify from most significant to least significant modification(s).  Use one or more of the following abbreviations in uppercase to identify your modification(s).  If using more then one abbreviation, separate with a comma with no space after the comma.
SC - Stormwater Canal
ID - Irrigation Ditch
IT - Interbasin Transfer
BC - Barge Canal
SD - Stormwater Ditch
PD - Pipe Diversion
CD - Channel Diversion
NC - Non-Contributing
KA - Karst
LE - Levee
NM - No Modifications
OC - Overflow Channel
DM - Dam at outlet or HU boundary
OT - Other

Hu_10_type:    Fifth Level Hydrologic Unit Type - (REQUIRED)
Populate this field with the hydrologic unit type from the list provided that most closely identifies the watershed.   Use any of the one-digit abbreviations in uppercase that is provided in the list.
S - "Standard" hydrologic unit - Any land HU with drainage flowing to a single outlet point, excluding non-contributing areas. This includes areas or small triangular wedges between adjacent HU's that remain after classic hydrologic units are delineated.  Some examples include "true", "classic", "composite", and "remnant" hydrologic units.
C - "Closed Basin" hydrologic unit - A drainage area that is 100% non-contributing. This means all surface flow is internal, no overland flow leaves the hydrologic unit through the outlet point.
F - "Frontal" hydrologic unit - Areas along the coastline of lakes, oceans, bays, etc. that have more than one outlet.  These HU's are predominantly land with some water areas at or near the outlet(s).
W - "Water" hydrologic unit - Hydrologic units that are predominantly water with adjacent land areas, ex. lake, easturies, harbors.
I - "Island" hydrologic unit - A hydrologic unit that is one or more islands and adjacent water out to the toe of the shore face.
U - "Unclassified" hydrologic unit - A hydrologic unit that can't be defined or doesn't fit into one of the types that have been listed.

Hu_12_ds: Sixth Level Downstream Hydrologic Unit Code - (FIELD REQUIRED, ATTRIBUTES OPTIONAL)
Populate this field with the 12-digit code of the 6th level hydrologic unit that is receiving the majority of the flow from the subwatershed.  Outlets created by ditching or other artificial drainage are not to be considered for this field.  If a HU flows into an ocean or the Gulf of Mexico populate this field with "OCEAN" and if a HU flows into one of the Great Lakes use the term "LAKE".  If a HU flows across international borders use "CANADA" or "MEXICO" depending on which country the HU drains into.  If an HU is  a closed basin, then populate this record with the term "CLOSED BASIN".

Hu_12_name: Sixth Level Hydrologic Unit Name - (FIELD REQUIRED, ATTRIBUTES OPTIONAL)
This field is for officially recognized names only.  Populate this field by following the directions in subsection 6.3 "Watershed and Subwatershed Naming Protocol".  The name used to attribute the subwatershed should be used only once within a 6th level unit. Some 10-digit HU were assigned the huc_12 number when no GNIS name was identified on the DRG-Es.


Hu_12_mod:	Sixth Level Hydrologic Unit Modifications - (REQUIRED)
This field should identify any type of modifications to natural overland flow that alters the location of the hydrologic unit boundary for a 12-digit subwatershed.  In the attribute field, identify from most significant to least significant modification(s).  Use one or more of the following abbreviations in uppercase to identify your modification(s).  If using more than one abbreviation, separate with a comma with no space after the comma.
SC - Stormwater Canal
ID - Irrigation Ditch
IT - Interbasin Transfer
BC - Barge Canal
SD - Stormwater Ditch
PD - Pipe Diversion
CD - Channel Diversion
NC - Non-Contributing
KA - Karst
LE - Levee
NM - No Modifications
OC - Overflow Channel
DM - Dam at outlet or HU boundary
OT - Other

Hu_12_type:    Sixth Level Hydrologic Unit Type - (REQUIRED)
Populate this field with the hydrologic unit type from the list provided that most closely identifies the subwatershed.   Use any of the one digit abbreviations in uppercase that is provided in the list.
S - "Standard" hydrologic unit - Any land HU with drainage flowing to a single outlet point, excluding non-contributing areas. This includes areas or small triangular wedges between adjacent HU's that remain after classic hydrologic units are delineated.  Some examples include "true", "classic", "composite", and "remnant" hydrologic units.
C - "Closed Basin" hydrologic unit - A drainage area that is 100% non-contributing.  This means all surface flow is internal, no overland flow leaves the hydrologic unit through the outlet point.
F - "Frontal" hydrologic unit - Areas along the coastline of lakes, oceans, bays, etc. that have more than one outlet.  These HU's are predominantly land with some water at or near the outlet(s).
W - "Water" hydrologic unit - Hydrologic units that are predominantly water with adjacent land areas, ex. lake, easturies.
I - "Island" hydrologic unit - A hydrologic unit that is one or more islands and adjacent water out to the toe of the shore face.
U - "Unclassified" hydrologic unit - A hydrologic unit that can't be defined or doesn't fit into one of the types that have been listed.

ArcInfo (.pat) and ArcView Polygon Format
Item name Width	Output	Type  (ArcView)  	N.Dec.		Example
Huc_8        8	  8	 C			-              01080201
Huc_10	  10	10	C			-             0108020103
Huc_12	  12	12	C			-	010802010310
Acres	    8	12	F	N		0		026739
States	  11	11	C			-		KS,MO,OK
Ncontrb_a   8	12	F	N		0		357
Hu_10_ds   10	10	C		                -		1710020504
Hu_10_name	80	80	C		-                        Upper Blue River
Hu_10_mod	20	20	C		-	              CB,NC,ID
Hu_10_type	1	1	C		-		S
Hu_12_ds	12	12	C		-		171002050402
Hu_12_name	80	80	C		-            Drift Creek-Big Bear River
Hu_12_mod	20	20	C		-		SD,KA,PD
Hu_12_type	1	1	C		-		C

2) .aat attributes

Hu_level:	Hydrologic Unit Level - (REQUIRED)
This field provides the means to create cartographically pleasing maps.  Populate this field with the highest hydrologic unit level (smallest number) for the line  (arc) represented by the record.  Record the level using numbers 1 through 6 representing each level with 1 being the highest and 6 the lowest level.  An example would be if a line represents a region, subregion, basin, subbasin, watershed, and subwatershed boundary, then this cell would be populated with a 1 (Region).  Example two would be if a line is a subbasin, watershed, and subwatershed boundary, then the cell would get a 4 (Subbasin).  Use one of the levels provided in the list below.
Level    Digit#    Name
1          2          Region
2            4          Subregion
3            6          Basin
4            8          Subbasin
5            10        Watershed
6            12        Subwatershed

Linesource:	Line Spatial Data Source - (REQUIRED)
The Linesource should indicate the base map source(s) used to delineate at 1:24,000 scale.  Populate the field using one of the standardized code(s) listed below in uppercase.  If using more than one code, separate with a comma with no space after the comma.
TOPO24 - Delineation from hardcopy 1:24,000 scale topographic maps
TOPO25 - Delineation from hardcopy 1:25,000 topgraphic maps, only Alaska and Caribbean
TOPO63 - Delineation from hardcopy 1:63,360 topographic maps, only Alaska and Caribbean
DRG24 - Delineation from 1:24,000 scale Digital Raster Graphics
DRG25 - Delineation from 1:25,000 Digital Raster Graphics, only Alaska and Caribbean
DRG63 - Delineation from 1:63,360 Digital Raster Graphics, only Alaska and Caribbean
DEM10 - Derived from 10 meter Digital Elevation Model
DEM30 - Derived from 30 meter Digital Elevation Model
NED30 - Derived from 30 meter National Elevation Dateset Model
EDNA30 - (formally NED-H), derived from 30 meter Elevation Derivatives for National
Applications
BATH"scale" (ex. BATH24) - Interpreted from NOAA 1:24,000 scale bathymetric data
HYPSO"scale" (ex. HYPSO24)- Delineated from 1:24,000 scale contour data
ORTHO"scale" (ex. ORTHO12) - Interpreted from 1:12,000 scale Ortho-imagery
DEDEM10 - Drainage enforced 10 meter Digital Elevation Model
DEDEM30 - Drainage enforced 30 meter Digital Elevation Model
GPS - Derived from Global Positioning System
LIDAR - Derived from LIDAR
IFSAR - Derived from IFSAR data
OTH - Other
UNK - Unknown
All other reference and source maps not listed should be noted in the metadata.
Meta_id:	Metadata ID Number - (REQUIRED)
Metadata ID is a code that identifies which metadata file applies to the arc. In many cases there will only be one metadata file. However, in some cases more than one metadata file may be created to identify different groups and/or procedures used to produce the lines. These separate metadata files may be identified for each separate arc. The metadata ID should be a 4-character code starting with the 2-letter state postal code, followed by a 2-digit sequence number. For example "OK01", "ID02", etc.

ArcInfo Line (.aat) Attribute Format
Item name       Width		Output		Type		N.Dec.	   Example
Hu_level		1		1		I		-		6
Linesource	20		20		C		-       DEM30,DRG24,GPS
Meta_id		4		4		C		-		OK01
Entity_and_Attribute_Detail_Citation:
Federal Geographic Data Committee. 2001. Federal Standards for Delineation of Hydrologic Unit Boundaries.  June 12, 2001 Draft  with emailed amendments to certain polygon and arc attribute structure.
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Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Department of Agriculture, Natural Resources Conservation Service, National Cartography and Geospatial Center
Contact_Address:
Address_Type: mailing address
Address:
P.O. Box 6567
City: Fort Worth
State_or_Province: Texas
Postal_Code: 76115
Country: U.S.
Contact_Voice_Telephone: 817 334 5559
Contact_Facsimile_Telephone: 817 334 5469
Resource_Description: Connecticut Watershed Boundary Dataset Poly
Distribution_Liability:
Although these data have been processed successfully on a computer system at the U.S. Department of Agriculture, no warranty expressed or implied is made by the agency regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty. The U.S. Department of Agriculture will warrant the delivery of this product in computer readable format, and will offer appropriate adjustment of credit when the product is determined unreadable by correctly
adjusted computer input peripherals, or when the physical medium is delivered in damaged condition. Request for adjustment of credit must be made within 90 days from the date of this shipment from the ordering site. 

Neither the U.S. Department of Agriculture, nor any of its agencies are liable for misuse of the data, nor is it liable for damage, transmission of viruses, or computer contamination through the distribution of these data sets. 

The United States Department of Agriculture (USDA) prohibits discrimination in its programs on the basis of race, color, national origin, sex, religion, age, disability, political beliefs and marital or familial status. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audio tape, etc.) should contact the USDA Office of Communications at (202) 720-5881 (voice) or (202) 720-7808 (TDD). 

To file a complaint, write the Secretary of Agriculture, U.S. Department of Agriculture, Washington, D.C. 20250, or call (202) 720-7327 (voice) or (202) 720-4107 (TDD). USDA is an equal opportunity employer.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: Arc Interchange File
Format_Version_Date: 20010712
Format_Specification:
non-compressed
Format_Information_Content:
spatial and keys
Transfer_Size: 3.423
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: http://www.lighthouse.nrcs.usda.gov/gateway/gatewayhome.html
Offline_Option:
Offline_Media: 8 mm cartridge tape
Recording_Capacity:
Recording_Density: 2.3
Recording_Density_Units: gigabytes
Recording_Format: tar
Offline_Option:
Offline_Media: 1/4-inch cartridge tape
Recording_Capacity:
Recording_Density: 150
Recording_Density_Units: megabytes
Recording_Format: tar
Fees: The charge for one data set is $XX.XX. A data set is one hydrologic unit boundary area in full quadrangle format and includes both spatial and attribute data.
Ordering_Instructions:
Call or write to organization listed under Distributor. Spatial line data are in DLG-3 optional format. Digital line graph files contain area records. A conversion legend is provided for each digital line graph file. Hydrologic unit codes and information concerning the hydrologic unit area are available in a companion ASCII attribute file.
Turnaround: 10 working days
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Metadata_Reference_Information:
Metadata_Date: 20010712
Metadata_Review_Date: 2002
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Department of Agriculture, Natural Resources Conservation Service
Contact_Person: GIS Specialist
Contact_Position: GIS Specialist
Contact_Address:
Address_Type: mailing address
Address:
344 Merrow Road
City: Tolland
State_or_Province: Connecticut
Postal_Code: 06084-3917
Contact_Voice_Telephone: (860) 871-4011
Contact_Facsimile_Telephone: (860) 871-4054
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Extensions:
Online_Linkage: http://www.esri.com/metadata/esriprof80.html
Profile_Name: ESRI Metadata Profile
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