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National Hydrography Dataset - Steams, Canals, Reaches
Metadata:
- Identification_Information
- Data_Quality_Information
- Spatial_Data_Organization_Information
- Spatial_Reference_Information
- Entity_and_Attribute_Information
- Distribution_Information
- Metadata_Reference_Information
Identification_Information:
Citation:
Citation_Information:
Originator: USGS National Hdyrographic Dataset
Publication_Date: Unknown
Title:
National Hydrography Dataset - Steams, Canals, ReachsGeospatial_Data_Presentation_Form: vector digital data
Online_Linkage: http://nhd.usgs.gov
Description:
Abstract:
The National Hydrography Dataset (NHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that comprise the nations surface water drainage system. It is based initially on the content of the U.S. Geological Survey 1:100,000-scale Digital Line Graph (DLG) hydrography data, integrated with reach-related information from the U.S. Environmental Protection Agency Reach File Version 3.0 (RF3). More specifically, it contains reach codes for networked features and isolated lakes, flow direction, names, stream level, and centerline representations for areal water bodies. Reaches are also defined to represent waterbodies and the approximate shorelines of the Great Lakes, the Atlantic and Pacific Oceans, and the Gulf of Mexico. The NHD also incorporates the National Spatial Data Infrastructure framework criteria set out by the Federal Geographic Data Committee.
Purpose:
The National Hydrography Dataset combines elements of the DLG and RF3: spatial accuracy and comprehensiveness from the DLG and network relationships, names, stream level, and a unique identifier (reach code) for surface water features from RF3. The NHD supersedes DLG and RF3 by incorporating them, not by replacing them. Users of DLG and RF3 will find the National Hydrography Dataset both familiar and greatly expanded and refined. The NHD provides a national framework for assigning reach addresses to water-related entities, such as industrial dischargers, drinking water supplies, fish habitat areas, wild and scenic rivers. Reach addresses establish the locations of these entities relative to one another within the NHD surface water drainage network in a manner similar to street addresses. Once linked to the NHD by their reach addresses, the upstream/downstream relationships of these water-related entities and any associated information about them can be analyzed using software tools ranging from spreadsheets to geographic information systems (GIS). GIS can also be used to combine NHD-based network analysis with other data layers, such as soils, land use and population, to help better understand and display their respective effects upon one another. Furthermore, because the NHD provides a nationally consistent framework for addressing and analysis, water-related information linked to reach addresses by one organization (national, state, local) can be shared with other organizations and easily integrated into many different types of applications to the benefit of all. The National Hydrography Dataset is designed to provide comprehensive coverage of hydrologic data for the U.S. While initially based on 1:100,000-scale data, the NHD is designed to incorporate - and encourage the development of - higher-resolution data required by many users. It will facilitate the improved integration of water-related data in support of the application requirements of a growing national user community and will enable shared maintenance and enhancement.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 1999
Currentness_Reference:
publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: Irregular
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -109.048
East_Bounding_Coordinate: -103.007
North_Bounding_Coordinate: 38.035
South_Bounding_Coordinate: 31.342
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Hydrography
Theme_Keyword: Stream / River
Theme_Keyword: Lake / Pond
Theme_Keyword: Canal / Ditch
Theme_Keyword: Reservoir
Theme_Keyword: Spring / Seep
Theme_Keyword: Swamp / Marsh
Theme_Keyword: Artificial Path
Theme_Keyword: Reach
Access_Constraints: None.
Use_Constraints:
None. Acknowledgment of the originating agencies would be appreciated in products derived from these data.
Native_Data_Set_Environment:
Windows NT Version 4.0 (Build 1381) Service Pack 6; ESRI ArcInfo 8.1.0.515Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
The accuracy of the attributes of the Digital Line Graph data is estimated to be 98.5 percent. One or more of the following methods were used to test attribute accuracy: - manual comparison of the source with hardcopy plots. - symbolized display of the digital line graph on an interactive computer graphic system. - Selected attributes that could not be visually verified on plots or on screen were interactively queried and verified on screen. In addition, software validated feature types and characteristics against a master set of types and characteristics, checked that combinations of types and characteristics were valid, and that types and characteristics were valid for the delineation of the feature. Feature types, characteristics, and other attributes conform to the Standards for National Hydrography Dataset (USGS, 1999) as of the date they were loaded into the database. All names on reaches were validated against a March 1999 extract from the Geographic Names Information System. The entry and identifier for the names match those in the Geographic Names Information System. The association of each name to reaches has not been methodically checked, and so a name may be applied to the wrong reaches. Anecdotal reviews indicate that 80 percent or more of the named reaches have the correct name. Reaches were delineated with a batch procedure and were checked extensively during the visual pass steps of processing. Based on automated quality assurance/quality control checks performed at various intervals during the processing, approximately 99 percent of the reaches are delineated according to standards.
Logical_Consistency_Report:
Points, nodes, lines, and areas conform to topological rules. Lines intersect only at nodes, and all nodes anchor the ends of lines. Lines do not overshoot or undershoot other lines where they are supposed to meet. There are no duplicate lines. Lines bound areas and lines identify the areas to the left and right of the lines. Gaps and overlaps among areas do not exist. All areas close.
Completeness_Report:
The completeness of the data reflects the content of the sources, which, in the initial release of the National Hydrography Dataset, most often are U.S. Geological Survey topographic maps. Features found on the ground may have been eliminated or generalized on the source graphic because of scale and legibility constraints. In general, streams longer than one mile (approximately 1.6 kilometers) were collected. Most streams that flow from a lake were collected regardless of their length. Only definite channels were collected so not all swamp/marsh features have stream/rivers delineated through them. Lake/ponds having an area greater than 6 acres (approximately 2.4 hectares) were collected. Note, however, that these general rules were applied unevenly among maps during compilation. Some map quadrangles have a much sparser pattern of hydrography than do adjoining maps and these differences continue in the digital rendition of these features. A priority for maintenance of the National Hydrography Dataset is the rectification of these differences. Transport reaches are defined on nearly all features of type stream/river, canal/ditch, artificial path, pipeline, and connector. Waterbody reaches are defined on the subset of lake/pond features that were identified as waterbodies during the development of Reach File Version 3. Most attention in applying geographic names was given to transport reaches that follow stream/rivers and waterbody reaches. Near the international boundaries with Canada and Mexico, only the parts of features within the United States are delineated. Detailed capture conditions are provided for every feature type in the Standards for National Hydrography Dataset (USGS, 1999), available online through http://mapping.usgs.gov/standards/.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Statements of horizontal positional accuracy are based on accuracy statements made for U.S.Geological Survey topographic quadrangle maps. These maps were compiled to meet National Map Accuracy Standards. For horizontal accuracy, this standard is met if at least 90 percent of points tested are within 0.02 inch (at map scale) of their true position. Additional offsets to positions may have been introduced where there are many features to improve the legibility of map symbols. In addition, the digitizing of maps is estimated to contain a horizontal positional error of less than or equal to 0.003 inch standard error (at map scale) in the two component directions relative to the source maps. Visual comparison between the map graphic (including digital scans of the graphic), and plots or digital displays of points, lines, and areas, is used to assess the positional accuracy of digital data. Linear features of the same type along the adjoining edges of data sets are aligned if they are within a 0.02 inch tolerance (at map scale). To align the features, the midpoint between the end of the corresponding features is computed, and the ends of features are moved to this point. Features outside the tolerance are not moved; instead, a feature of type connector was added to join the features.
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
Statements of vertical positional accuracy for elevation of water surfaces are based on accuracy statements made for U.S. Geological Survey topographic quadrangle maps. These maps were compiled to meet National Map Accuracy Standards. For vertical accuracy, this standard is met if at least 90 percent of well-defined points tested are within one-half contour interval of the correct value. Elevations of water surface printed on the published map meet this standard; the contour intervals of the maps vary. These elevations were transcribed into the digital data; the accuracy of this transcription was checked by visual comparison between the data and the map.
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Complete chain
Point_and_Vector_Object_Count: 81825
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Label point
Point_and_Vector_Object_Count: 12239
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains
Point_and_Vector_Object_Count: 12239
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Node, planar graph
Point_and_Vector_Object_Count: 78151
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Point
Point_and_Vector_Object_Count: 4
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Composite object
Point_and_Vector_Object_Count: 4692
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Composite object
Point_and_Vector_Object_Count: 11590
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Composite object
Point_and_Vector_Object_Count: 169
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Composite object
Point_and_Vector_Object_Count: 5071
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Composite object
Point_and_Vector_Object_Count: 5987
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Grid_Coordinate_System:
Grid_Coordinate_System_Name: Universal Transverse Mercator
Universal_Transverse_Mercator:
UTM_Zone_Number: 13
Transverse_Mercator:
Scale_Factor_at_Central_Meridian: 0.999600
Longitude_of_Central_Meridian: -105.000000
Latitude_of_Projection_Origin: 0.000000
False_Easting: 500000.000000
False_Northing: 0.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.003675
Ordinate_Resolution: 0.003675
Planar_Distance_Units: meters
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
Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: nhd.aat
Attribute:
Attribute_Label: FNODE#
Attribute_Definition:
Internal node number for the beginning of an arc (from-node).
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Whole numbers that are automatically generated.Attribute:
Attribute_Label: TNODE#
Attribute_Definition:
Internal node number for the end of an arc (to-node).
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Whole numbers that are automatically generated.Attribute:
Attribute_Label: LPOLY#
Attribute_Definition:
Internal node number for the left polygon.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Whole numbers that are automatically generated.Attribute:
Attribute_Label: RPOLY#
Attribute_Definition:
Internal node number for the right polygon.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Whole numbers that are automatically generated.Attribute:
Attribute_Label: LENGTH
Attribute_Definition:
Length of feature in internal units.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Positive real numbers that are automatically generated.Attribute:
Attribute_Label: NHD#
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: NHD-ID
Attribute_Definition:
User-defined feature number.
Attribute_Definition_Source:
ESRI
Detailed_Description:
Entity_Type:
Entity_Type_Label: nhd.pat
Attribute:
Attribute_Label: AREA
Attribute_Definition:
Area of feature in internal units squared.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Positive real numbers that are automatically generated.Attribute:
Attribute_Label: PERIMETER
Attribute_Definition:
Perimeter of feature in internal units.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Positive real numbers that are automatically generated.Attribute:
Attribute_Label: NHD#
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: NHD-ID
Attribute_Definition:
User-defined feature number.
Attribute_Definition_Source:
ESRI
Detailed_Description:
Entity_Type:
Entity_Type_Label: nhd.nat
Attribute:
Attribute_Label: ARC#
Attribute:
Attribute_Label: NHD#
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: NHD-ID
Attribute_Definition:
User-defined feature number.
Attribute_Definition_Source:
ESRI
Attribute:
Attribute_Label: COM_ID
Attribute:
Attribute_Label: FTYPE
Attribute:
Attribute_Label: ABOVE_ID
Attribute:
Attribute_Label: BELOW_ID
Detailed_Description:
Entity_Type:
Entity_Type_Label: nhd.ratdrain
Attribute:
Attribute_Label: DRAIN#
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: DRAIN-ID
Attribute_Definition:
User-defined feature number.
Attribute_Definition_Source:
ESRI
Attribute:
Attribute_Label: COM_ID
Attribute:
Attribute_Label: RCH_COM_ID
Attribute:
Attribute_Label: WB_COM_ID
Attribute:
Attribute_Label: FTYPE
Attribute:
Attribute_Label: FCODE
Attribute:
Attribute_Label: METERS
Detailed_Description:
Entity_Type:
Entity_Type_Label: nhd.ratrch
Attribute:
Attribute_Label: RCH#
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: RCH-ID
Attribute_Definition:
User-defined feature number.
Attribute_Definition_Source:
ESRI
Attribute:
Attribute_Label: COM_ID
Attribute:
Attribute_Label: RCH_CODE
Attribute:
Attribute_Label: RCH_DATE
Attribute:
Attribute_Label: LEVEL
Attribute:
Attribute_Label: METERS
Attribute:
Attribute_Label: GNIS_ID
Attribute:
Attribute_Label: NAME
Detailed_Description:
Entity_Type:
Entity_Type_Label: nhd.patlm
Attribute:
Attribute_Label: AREA
Attribute_Definition:
Area of feature in internal units squared.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Positive real numbers that are automatically generated.Attribute:
Attribute_Label: PERIMETER
Attribute_Definition:
Perimeter of feature in internal units.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Positive real numbers that are automatically generated.Attribute:
Attribute_Label: LM#
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: LM-ID
Attribute_Definition:
User-defined feature number.
Attribute_Definition_Source:
ESRI
Attribute:
Attribute_Label: COM_ID
Attribute:
Attribute_Label: FTYPE
Attribute:
Attribute_Label: FCODE
Attribute:
Attribute_Label: ELEV
Attribute:
Attribute_Label: STAGE
Attribute:
Attribute_Label: SQ_KM
Attribute:
Attribute_Label: GNIS_ID
Attribute:
Attribute_Label: NAME
Detailed_Description:
Entity_Type:
Entity_Type_Label: nhd.patrch
Attribute:
Attribute_Label: AREA
Attribute_Definition:
Area of feature in internal units squared.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Positive real numbers that are automatically generated.Attribute:
Attribute_Label: PERIMETER
Attribute_Definition:
Perimeter of feature in internal units.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Positive real numbers that are automatically generated.Attribute:
Attribute_Label: RCH#
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: RCH-ID
Attribute_Definition:
User-defined feature number.
Attribute_Definition_Source:
ESRI
Attribute:
Attribute_Label: COM_ID
Attribute:
Attribute_Label: RCH_CODE
Attribute:
Attribute_Label: RCH_DATE
Attribute:
Attribute_Label: SQ_KM
Attribute:
Attribute_Label: GNIS_ID
Attribute:
Attribute_Label: NAME
Detailed_Description:
Entity_Type:
Entity_Type_Label: nhd.patwb
Attribute:
Attribute_Label: AREA
Attribute_Definition:
Area of feature in internal units squared.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Positive real numbers that are automatically generated.Attribute:
Attribute_Label: PERIMETER
Attribute_Definition:
Perimeter of feature in internal units.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Positive real numbers that are automatically generated.Attribute:
Attribute_Label: WB#
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: WB-ID
Attribute_Definition:
User-defined feature number.
Attribute_Definition_Source:
ESRI
Attribute:
Attribute_Label: COM_ID
Attribute:
Attribute_Label: RCH_COM_ID
Attribute:
Attribute_Label: FTYPE
Attribute:
Attribute_Label: FCODE
Attribute:
Attribute_Label: ELEV
Attribute:
Attribute_Label: STAGE
Attribute:
Attribute_Label: SQ_KM
Attribute:
Attribute_Label: GNIS_ID
Attribute:
Attribute_Label: NAME
Overview_Description:
Entity_and_Attribute_Overview:
The National Hydrography Dataset is a comprehensive set of digital spatial data that encodes information about naturally occurring and constructed bodies of water, paths through which water flows, and related entities. The information encoded about features includes classification by type, other characteristics, a unique common identifier, the feature length or area, and (rarely) the elevation of the surface of water pools and a description of the stage of the elevation. For reaches, encoded information includes a reach code, the date the reach code was assigned, a unique common identifier, the reach length or area, and, for transport reaches, the stream level. Geographic names, and their identifiers in the Geographic Names Information System, are assigned to reaches or, if no reach is available, to features. The data also contain relations among reaches that encode the direction of water flow, metadata, and information that supports the exchange of future updates and improvements to the data.
Entity_and_Attribute_Detail_Citation:
The names and definitions of all feature types, characteristics, and values are in U.S. Geological Survey, 1999, Standards for National Hydrography Dataset: Reston, Virginia, U.S.Geological Survey. The document is available online through http://mapping.usgs.gov/standards/. Information about tables and fields in the data are available from the user documentation for the National Hydrography Dataset.
Distribution_Information:
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Transfer_Size: 62.216
Metadata_Reference_Information:
Metadata_Date: 20001204
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Contact_Person:
Contact_Address:
Address_Type:
City:
State_or_Province:
Postal_Code:
Contact_Voice_Telephone:
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