Abstract:The Watershed Boundary Dataset (WBD) is a complete digital hydrologic unit national boundary layer that is at the Subwatershed (12-digit) level. It is composed of the watershed boundaries delineated by state agencies at the 1:24,000 scale. Please refer to the individual state metadata as the primary reference source. To access state specific metadata, go to the following link to view documentation created by agencies that performed the watershed delineation. ftp://ftp.ftw.nrcs.usda.gov/pub/wbd/hu/metadata. This data set is a complete digital hydrologic unit boundary layer to the Subwatershed (12-digit) 6th level. This data set consists of geo-referenced digital data and associated attributes created in accordance with the "FGDC Proposal, Version 1.0 - Federal Standards For Delineation of Hydrologic Unit Boundaries 3/01/02" (http://www.ftw.nrcs.usda.gov/huc_data.html). Polygons are attributed with hydrologic unit codes for 4th level sub-basins, 5th level watersheds, 6th level subwatersheds, name, size, downstream hydrologic unit, type of watershed, non-contributing areas and flow modification. Arcs are attributed with the highest hydrologic unit code for each watershed, linesource and a metadata reference file.Please refer to the Metadata contact if you want access to the WBD national data set.
Purpose:The purpose of the data set is to provide access to the WBD as a single geospatial data layer. Individual state watershed boundaries were merged together to create a seamless national WBD. The Watershed and Subwatershed hydrologic unit boundaries provide a uniquely identified and uniform method of subdividing large drainage areas. The smaller sized 6th level sub-watersheds (up to 40,000 acres) are useful for numerous application programs supported by a variety of local, State, and Federal Agencies. This data set is intended to be used as a tool for water-resource management and planning activities, particularly for site-specific and localized studies requiring a level of detail provided by large-scale map information. The Watershed and Subwatershed hydrologic unit boundaries provide a uniquely identified and uniform method of subdividing large drainage areas. The smaller sized 6th level sub-watersheds (up to 40,000 acres) are useful for numerous application programs supported by a variety of local, State, and Federal Agencies. This data set is intended to be used as a tool for water-resource management and planning activities, particularly for site-specific and localized studies requiring a level of detail provided by large-scale map information. The dataset will be appended to a larger seamless nationally consistant geospatial database as other states complete their portion of the watershed boundary dataset.
Supplemental Information:Please refer to the individual state metadata as the primary reference source. To access state specific metadata, go to the following link to view documentation created by agencies that performed the watershed delineation. ftp://ftp.ftw.nrcs.usda.gov/pub/wbd/hu/metadata This service is called 'Public_Metadata' and is located at http://geodata.epa.gov. Users can take the following steps to connect to the EPA public metadata service (Note: This method requires ESRI ArcGIS software):1. Open ArcCatalog 2. In the ArcCatalog Table of Contents, click on 'GIS Servers' to expand the list 3. Click on 'Add ArcIMS Server' 4. Enter http://geodata.epa.gov in the URL of server field 5. Click 'Get List' You should see a number of services listed under the geodata.epa.gov entry. Select the 'Public_Metadata' entry to open the public metadata service. Within the public metadata service, you will see a number of folders. Each folder may contain metadata records associated with that organization. Expand the folder to view the contents.

Progress:Complete
Update Frequency:Irregular

Theme Keywords:ISO 19115 Topic Category, boundaries, environment, geoscientificInformation, inlandWaters, location, EPA GIS Keyword Thesaurus, Ecosystem, Environment, Estuary, Ground Water, Land, Management, Monitoring, Natural Resources, Regulatory, Surface Water, Water, User keywords, watershed, WBD, watershed boundaries, HUC, hydrologic unit code, watershed level, HUC12, 12-digit HUC, hydrologic unit boundary, subwatershed, watershed boundary, hydrologic units, User, Watershed Boundary Dataset, waters10, waters_wbd.wbd_huc12_os, waters_wbd.wbd_huc12_sde
Place Keywords:United States

Access Constraints:None.
Usage Constraints:The distributor shall not be held liable for improper or incorrect use of this data, based on the description of appropriate/inappropriate uses described in this metadata document. It is strongly recommended that this data is directly acquired from the distributor and not indirectly through other sources which may have changed the data in some way. These data should not be used at scales greater than 1:24,000 for the purpose of identifying hydrographic watershed boundary feature locations in STATE. The publisher makes no claims for the data's suitability for other purposes. The publisher should be acknowledged as the data source in products derived from these data. The Watershed Boundary Dataset is public information and may be interpreted by all organizations, agencies, units of government, or others based on needs; however, they are responsible for the appropriate application of the data. Federal, State, or local regulatory bodies are not to reassign to the publisher or the Natural Resources Conservation Service any authority for the decisions they make. The Natural Resources Conservation Service will not perform any evaluations of these maps or purposes related solely to State or local regulatory programs. Photographic or digital enlargement of these maps to scales greater than that at which they were originally delineated can result in 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 from the source distributor..