Identification_Information: Citation: Citation_Information: Originator: Virginia Dept of Conservation and Recreation (VADCR) Division of Soil and Water Conservation (DSWC) Publication_Date: 20090915 Title: The Virginia Portion of the National Watershed Boundary Dataset (NWBD) Edition: Federal form of version 4 of the NWBD sixth order units for Virginia. Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: hydrologic units Issue_Identification: VA NWBD Publication_Information: Publication_Place: Richmond, Virginia Publisher: Virginia DCR-DSWC Description: Abstract: These are the new, and thrice revised, national fifth and sixth order hydrologic units for Virginia. They have been created in compliance with the new Federal Standards for Delineation of Hydrologic Unit Boundaries (1 October 2004) and therefore differ from the previous sixth order (14 digit) hydrologic units of Virginia as developed by DCR and the USDA in 1995 from the hydrologic unit delineation standards of 1992. This dataset covers the whole state and is seamless with surrounding state's NWBD product although subject to change as the surrounding states make final changes to their data layers. Revised first through fifth order units are obtainable from codes in this layer. Purpose: Developed as part of a seamless hydrologic unit product for the nation. To be used for more detailed watershed planning work in the state than can be performed using lower order units. This becomes the official statewide fifth and sixth order hydrologic unit delineations for Virginia. Supplemental_Information: Origin: Version 1 of the sixth order hydrologic units for Virginia were originally digitized at ISSL, VPI&SU in 1989 off of the USGS 7.5 minute quadrangle maps. Delineations were made by the Virginia Department of Conservation and Recreation (DCR) and the USDA Soil Conservation Service, now the Natural Resources Conservation Service (NRCS). The line and attribute data were delivered to the VA DCR in DLG3 format. There were 492 units in Virginia at this version. Units were uniquely identified by a three character string and were sequentially coded downstream to upstream. Revisions: 1995 Permutation: For a number of reasons - greater accuracy, new HU delineation standards, new watershed projects, interstate coordination, increased use of watershed geography by the Virginia Department of Environmental Quality (DEQ) - the NRCS, DCR, and DEQ decided in June of 1993 to revise Virginia's existing sixth order hydrologic unit system. All linework was checked for accuracy, redelineated, and digitally recaptured by DCR where improvements could be made. Some watersheds were merged, others divided, and still others significantly adjusted versus their 1989 form. Coordination with all nearby states resulted in the adjustment of many border units to create a greater continuance of linework from state to state. The resulting 494 units of the 1995 version were then recoded upstream to downstream (opposite the 1989 order) to meet new guidelines. Unit coding continued to use a three character string as per the original version but their sequential order was also reversed. Textual descriptions of the units were revised and standardized. The units of this system are often referred to as the 14 digit hydrologic units, since that is how large the official sixth order unit numbering is (versus the 3 character string). Initial NWBD Permutation: The NWBD of Virginia has been developed by the Virginia DCR to comply with the new federal standards for the delineation of hydrologic unit boundaries. It uses the 1995 sixth order hydrologic unit system as it's basis. Where at all possible, NWBD units were delineated so as to preserve the delineation intentions of the 1995 product, which is widely used by state agencies. This adherence to previous products is not part of the new standard. Despite the aim to make the NWBD units be the same as or subsets of the 1995 sixth order units, a number of boundary changes were made to accomodate the smaller unit size option of the sixth order units of the NWBD. Although 14 digit hydrologic units of the 1995 version that are of a size that is within the acceptable range of the NWBD sixth order units were usually maintained, almost all larger units were divided. The primary differences between the sixth order units of the NWBD and the 14 digit units of 1995 are the following improvements: (1) more precise linework. All linework was redigitized in a heads up manner off of either the DRGs of the USGS 7.5 minute topographic quad maps, digital NOAA charts, or quarter quad imagery. This included delineations which previously existed as this process produced a more precise product than did the previous process of digitizing from paper 7.5 minute topographic quadrangles. Delineations were still made onto the original 807 7.5 minute topographic quadrangle maps for Virginia that the 1995 product was delineated on. (2) incorporation of the October 2004 "Federal Standards for Delineation of Hydrologic Unit Boundaries, Version 2.0", which is supported by a consortium of federal agencies and not just the USDA. (3) unit sizes of the sixth order units are much smaller, typically from 10,000 to 40,000 acres, whereas they averaged a just over 54,000 acres previously. (4) water side delineations of frontal units now go to the toeface of the shore, which varies from 10 feet deep in the Bays to 30 feet deep in the Atlantic. Delineations also proceed out to the 3 nautical mile territorial limit in the Atlantic. (5) units are seamless bewteen states in both linework and numbering. This was not true for the sixth order units of the 1995 version. (6) fifth order units are now officially referenced using a 10 digit string and sixth order units are referenced using a 12 digit string. The 1995 version required 11 and 14 digits for the same references. Units are coded uniquely and by drainage basin beginning upstream and proceeding sequentially to each unit downstream. The general order is main stem followed by tributairy, with no unit flowing into a unit of a lower reference code. (7) other useful attributes have been added, including unit type and modifiers, state codes, and linework source. (8) the standards-defying second and fourth order unit boundaries between (a) Smith Point on the south shore of the Potomac confluence with the Chesapeake Bay, and (b) the Atlantic Ocean, have been corrected. Version 2 of the NWBD Permutation: Following 10 months of use enough attribute coding errors were found in the initial release of the VA NWBD to warrant a revised, corrected version in May of 2007. No linework changes were made. Attribute changes made between versions 1 and 2 of the VA NWBD can be found in the spreadsheet "updates" from the DCR Hydrologic Unit Geography web page at www.dcr.virginia.gov/soil_&_water/hu.shtml. Most applied to the sixth order coding but a few apply to the fifth order coding. Many involve continued efforts to keep the NWBD seamless between the states. All told, less than 4/10 of 1% of the 27,600+ developer-entered attributes required correction. Version 3 of the NWBD Permutation: Modifications to the North Carolina, West Virginia, Maryland, and Pennsylvania NWBD products as well as irregularities found in the Virginia layer during tests to determine seamless issues by Laura Davenport (USDA) and Sarah Walton (USGS) in May 2008 neccesited an update to Version 2 of the VA NWBD. Attribution issues similar to those found in these tests were edited as part of this update as well. By attribute, these changes affected: HU_10_NAME (3), HUC_12 (10), HU_12_NAME (13), STATES (1), ACRES (13, UNITACRES in VA form), HUC_10 (2), HU_10_DS (1),and HU_12_DS (8). There was also three linework additions that created new polygons but not new units. Issues included: (A) HUC_12, HUC_10, and HU_12_DS renumbering due to renumberings in other states, (B) unit names including "Headwaters" must have the term before the feature name, (C) unit names cannot include the term "Deep" (Atlantic, Chesapeake, and Potomac), but may now include the unit code # (feature-#). (D) federal format unit names with more than two features, with two being the max. In addition, the META_ID variable was added to the polygon records. Initial values for the polygon and the arc entries for META_ID were VA01 but were changed to VA02 for those polygons with attribution changes in May 2007 (v2) and changed to VA03 for arcs modifed in version 3 and for polygons with attribution changes in Sept/Oct 2008. A spreadsheet of the changes made between the versions of the VA form of the NWBD can be accessed from the DCR Hydrologic Unit Geography web page at: www.dcr.virginia.gov/soil_&_water/hu.shtml. Version 4 of the NWBD Permutation: Completion of the NWBD 6th order units in the surrounding states has lead to the minor adjustments made to create this version of the Virginia layer. This includes small boundary adjustments at state borders and a few attribution corrections. Attribution changes include the following for polygons: HU_10_NAME (1), HU_12_NAME (4), and ACRES (2). For arc attributes, HU_LEVEL was modified in 27 places. There was also six minor linework modifications that created no new polygons or units. The largest only affected 10 acres. In addition, the META_ID variable was changed to VA04 for all polygons affected by polygon attribute changes and all arcs affected by arc attribute changes or geometry modifications. A spreadsheet of the changes made between the versions of the VA form of the NWBD can be accessed from the DCR Hydrologic Unit Geography web page at: www.dcr.virginia.gov/soil_&_water/hu.shtml. State vs Federal Form: All versions of the Virginia NWBD have two forms - one used internally by the state and jurisdictions of the state, and another "federal" form that strictly meets the standards as stated in the Federal Standards for Delineation of Hydrologic Unit Boundaries. This metadata file describes the Virginia form. The differences between the two are: (A) the inclusion of a 4 character strings used to identify the fifth and sixth order units in the state version. (B) more than two features are allowed in the unit name in the state form. (C) unit names are in order of large to small feature in the state form, the reverse in the federal form. (D) water features with two common references are both entered in the state form with a forward slash connector (i.e. Leesville Lake/Roanoke River) whereas either only one reference is used in the federal form or they are the maximum two listed features. (E) the actual percentage of water in a unit is noted in the state form whereas this info is just used for determining and noting when a unit is of type "water". (F) the tidal notation is only added to the state form. (G) the database tables are more normalized in the state form. (H) and the state form includes a number of files that relate to the layer (long listings of water features, main stem descriptions, and the geographic extent relationships between NWBD and previous 14-digit units). Reviews_Applied_to_Data: Advance copies were sent to the USDA NRCS in VA, the USFS in VA, the Virginia DEQ, and VIMS for comment. Copies of portions of the VA NWBD also went to the agencies in the surrounding states during linework and coding development for their review and use in making a seamless product. DCR, Virginia DEQ, and the Virginia office of the USDA NRCS had previously reviewed the base 1995 product. A compliance team of federal agency representatives (USDA, EPA, USGS) reviewed the procedures and draft product in a visit to the DCR office and provided comment. Near complete copies of the VA NWBD were isued to the EPA office in Philadelphia, EPA contractors and other NWBD developers in the surrounding states, the USGS office in Richmond, and the USDA NRCS offices in Richmond and Harrisonburg. The latest copies of the NWBD of bordering states were obtained at the last possible moment in a final review of linework and version 1 attribution across state boundaries, as this was the last portions of the Virginia NWBD development work to be completed. Possible problems found by users who contacted the VA DCR were either explained or logged for the subsequent development of version 2 of this effort. An evaluation of the types of noted attribution problems that were found to be errors resulted in an exhaustive evaluation of this product prior to the creation and release of version 2. The USDA office in Fort Worth Texas coordinated certification of the federal form of versions 1 and 2 of this product as well as for other states. The USGS also reviewed version 2 of the Virginia layer as part of a review of North Carolina's layer. In addition, an EPA contractor reviewed the Upper Potomac units in Virginia as part of their work on the NWBD in Pennsylvania and the units shared by Maryland and Virginia in general. A USDA representative reviewed the units shared by Virginia and West Virginia. These recent reviews resulted in the need for changes in Virginia units near state borders as reflected in version 3. DCR performed the review that resulted in the linework and arc attribution changes of version 4 at the time that the USDA claimed all states were initially completed in their NWBD development. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20050318 Ending_Date: Present Currentness_Reference: Publication date of sources Status: Progress: Complete but uncertified Maintenance_and_Update_Frequency: Changes to the linework detail are made whenever reason can be shown to do so. These changes are usually so minor as to only be visible at a very large scale display, and do not constitute a significant variance from the original form of this version. Should any significant linework errors or any further significant attribution errors be found after Sept 2009 they will be logged for revision in a fifth version. Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -83.675 East_Bounding_Coordinate: -75.176 North_Bounding_Coordinate: 39.466 South_Bounding_Coordinate: 36.541 Keywords: Theme: Theme_Keyword_Thesaurus: none Theme_Keyword: hydrologic units Theme_Keyword: watersheds Theme_Keyword: Watershed Boundary Dataset Theme_Keyword: fifth order Theme_Keyword: sixth order Place: Place_Keyword_Thesaurus: Counties and County Equivalents of the United States and the District of Columbia (FIPS Pub 6-3). Place_Keyword: Virginia Access_Constraints: none Use_Constraints: Linework and hydrologic unit codes should not be altered except by the developer, as this dataset constitutes the accepted digital version of these geographic units for all state and federal programs referencing the VA NWBD. Use at scales greater than 1:24,000 is discouraged. Crediting the VA DCR for dataset development is requested. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: Virginia Dept. of Conservation & Recreation - DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Contact_Facsimile_Telephone: 804 371 2630 Contact_Electronic_Mail_Address: karl.huber@dcr.virginia.gov Hours_of_Service: 0900-1800 Data_Set_Credit: This dataset has been developed by the Virginia Department of Conservation and Recreation (DCR) with assistance from the Virginia Tech Biological Systems Engineering Dept. It is built upon an earlier version developed by the VA DCR with assistance from the USDA NRCS and the VA DEQ. Native_Data_Set_Environment: UNIX (Solaris), ARC/INFO v7.2.1 thru ArcGIS 9.3 Cross_Reference: Citation_Information: Originator: USDA-NRCS Publication_Date: 2000 Title: Enhanced DRGs of Virginia Edition: 2000 Geospatial_Data_Presentation_Form: digital raster graphic Series_Information: Series_Name: Enhanced DRGs Issue_Identification: Virginia Quads Publication_Information: Publication_Place: Fort Worth, Texas Publisher: USDA-NRCS Cross_Reference: Citation_Information: Originator: Virginia Dept. of Conservation and Recreation - DSWC Publication_Date: 19950601 Title: Virginia's Revised 14 Digit Hydrologic Unit Boundaries. Edition: 2 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: hydrologic units Issue_Identification: version 2 Publication_Information: Publication_Place: Richmond, Virginia Publisher: Virginia DCR with USDA NRCS Other_Citation_Details: Jointly developed by DCR and USDA NRCS. Cross_Reference: Citation_Information: Originator: Virginia Dept. of Conservation and Recreation - DSWC Publication_Date: 19910901 Title: Virginia's (Original) 14 Digit Hydrologic Unit Boundaries. Edition: 1 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: hydrologic units Issue_Identification: version 1 Publication_Information: Publication_Place: Richmond, Virginia Publisher: Virginia DCR with USDA NRCS Other_Citation_Details: With contractual help of ISSL. Cross_Reference: Citation_Information: Originator: U.S. Water Resources Council Publication_Date: 1974 Title: Hydrologic Unit Map of Virginia Edition: unknown Geospatial_Data_Presentation_Form: map Publication_Information: Publication_Place: Reston, Virginia Publisher: USGS Other_Citation_Details: Only useful to the fourth order. Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The assigning of all attributes in this dataset to the arcs and polygons of the sixth order hydrologic units has been done by the state personnel with the authority and resources to do so. Their work has been reviewed by interested agencies of the Commonwealth and Federal government. Any miscoded attribution is corrected upon discovery. Because not all states have completed their NWBD at the same time, some attribution in units at state borders is the expected correct coding as opposed to the verified coding. This mostly affects the downstream unit codes and unit names. Likewise, because there are no gaps in the sequential sixth order numbering it is possible that subsequent revisions in bordering states will require revisions to the current 12 digit unit reference codes. The self-imposed unit coding rule to have units only flow into other units with higher unit codes (i.e. 0507020102 cannot flow into 0507020101) could not be strictly enforced at all orders. It was not strictly followed in the original coding of units for the first through fourth orders in the 1970s (i.e. 03010105 flows into 03010104, and fourth order units of 020801 flow into 02080101). Unit codes up to the fourth order were considered established and not open to recoding as part of the NWBD development except for rare cases where mistakes had been made and all federal and state parties were agreeable to recoding. The higher order flow direction of coding has been adhered to for all fifth and sixth order units within all fourth order units. Reported downstream unit codes for sixth order units that, at their confluence, join to flow across a fifth order unit boundary disagree by design between the actual unit boundary alignment regarding flow and the way the downstream unit attribute is recorded. As an example, if units A and B join to flow into C, and units A-C are all in the same fifth order unit, units A and B will both have a downstream unit code of C. If however unit C is in a different fifth order unit from A and B, the downstream unit code attribute will still say that they both flow into C but a close inspection of the linework at the confluence will show that B appears to flow into A (or vice versa) before they jointly flow into C. This was required by the Compliance Team, who decided that to not make this linework modification would cause the effect of having two distinct inflows (A and B's) from one fifth order unit to the next. Logical_Consistency_Report: All arcs are used to define hydrologic unit boundaries. There are no dangling arcs, nor does any polygon contain more than one label. Boundaries at both the fifth and sixth order are or will be seamless across the boundaries of the adjoining states at each order. Fifth order units may be constructed by aggregating sixth order units without exception. Completeness_Report: While this dataset could now be considered complete for VA other states may continue to modify their units in such a way as to affect the Virginia NWBD. This data set may also face more minor changes in the future depending on evolving NWBD standards, geomorphological change, and the need to correctly overlay the high res NHD for Virginia. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Hydrologic unit boundary locations as captured from the DRGs will degrade in accuracy from the value reported below where topography is flat and contours more widely dispersed from one another, since contours are the basis for positioning hydrologic unit boundaries. Accuracy will be most compromised along the Chesapeake Bay and Atlantic Ocean shorelines, particularly on barrier islands, due to the speed of geomorphological change in these areas. Quantitative_Horizontal_Positional_Accuracy_Assessment: Horizontal_Positional_Accuracy_Value: 14.342 Horizontal_Positional_Accuracy_Explanation: Calculated as the offset in meters from true ground location due to the National Map Accuracy Standards of the source map plus the resolution of the capture of coordinates from this source at display scale plus the maximum movement possible due to processing tolerances applied. Therefore the value represents the worst accuracy expected under normal data capture and processing procedures. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Hession, W. Cully Publication_Date: 19910901 Title: Virginia's Hydrologic Units Source_Scale_Denominator: 24000 Type_of_Source_Media: 7.5 minute quad maps Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1949 Ending_Date: 1987 Source_Currentness_Reference: out of date Source_Citation_Abbreviation: 1991 HUs Source_Contribution: base upon which 1995 updates were made Source_Information: Source_Citation: Citation_Information: Originator: Huber, Karl Publication_Date: 19950601 Title: Virginia's Hydrologic Units Source_Scale_Denominator: 24000 Type_of_Source_Media: 7.5 minute quad maps Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1949 Ending_Date: 1987 Source_Currentness_Reference: out of date Source_Citation_Abbreviation: 1995 HUs Source_Contribution: base upon which NWBD was developed Process_Step: Process_Description: Delineation - the rough delineation of the new sixth order NWBD units were made to the paper USGS 7.5 minute topographic quad maps on which the 1995 version of the jurisdiction and hydrologic units were drawn. Process_Date: 200403 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Digitize - the refined linework for sixth order hydrologic unit boundaries was captured on enhanced DRGs of the USGS 7.5 minute topographic quad maps by performing heads-up digitizing. The paper maps containing the rough delineations of new sixth order boundaries were used as indicators of where refined linework was to be captured. Process_Date: 200406 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Seamless Boundaries - many map services and much correspondance with the NWBD developers in surrounding states and in the federal government was necessary to assure a seamless dataset across state boundaries. To develop the many map services required the creation of many shapefiles of specific areas of NWBD concern. Process_Date: 200408 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber, Gina Beale, Rebecca Cottle Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Updates - evolving NWBD boundary issues in other states required some late changes to the NWBD dataset not originally delineated on the paper quad maps. Process_Date: 200408 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Arc Attribution - the boundary lines of this data set were attributed with references to the source of each arc and the lowest order hydrologic unit that uses it. Process_Date: 200408 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gina Beale Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 0297 Process_Step: Process_Description: Polygon Attribution - two databases of unit attributes were created. One was the master table of attributes of the sixth order units. The other was the master table of attributes of the fifth order units. Attributes include items such as unit names, modifiers, types, codes, and downstream codes. These tables will eventually be joined to the polygon attribute table to create the federal form of this layer. Process_Date: 200408 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gina Beale, Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 0297 Process_Step: Process_Description: Mid-Atlantic Resolutions - remaining coastal issues and state dataset differences for the mid-Atlantic states were resolved by a meeting of those states in Dover DE. Changes were made to the NWBD to reflect these decisions, particularly changes to the original 2nd and 4th order unit boundaries and codes. Process_Date: 20050303 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber, Gina Beale Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Projected - initial UTM cover of combined NWBD and jurisdiction boundaries was projected to Lambert NAD83 with Virginia standards. Process_Date: 20050315 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gina Beale Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 0297 Process_Step: Process_Description: Dissolve - the NWBD boundaries were separated from the jurisdiction boundaries by dissolving on HUC codes to create covers at each order (1-6) of hydrologic units. Process_Date: 20050315 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Reselection Test - arcs were reselected from the combined NWBD-jurisdiction boundary cover based on AAT HU_LEVEL, LPOLY#, and RPOLY# values. Polygons were built from these arcs and the PAT compared to the PAT created by dissolving on HUC codes. This was done for all orders (1-6). Where the reselection created polygons did not match the dissolved created polygons, bad HU_LEVEL codes were found and corrected. Process_Date: 20050315 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Contact_Organization: VA DCR-DSWC Process_Step: Process_Description: Updates - evolving standards (March 2002 to Oct 2004) required some additions to the set of NWBD attributes. Changes were made to the master fifth and sixth order unit tables, including stream name order. Process_Date: 20050317 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber, Gina Beale Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Projected - fifth and sixth order covers of NWBD were projected to Albers NAD83 with N. America standards for best polygon acres determination and then reprojected back to Lambert. Process_Date: 20050317 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gina Beale Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 0297 Process_Step: Process_Description: Joining of Attribution - the master tables of attributes of the sixth and fifth order units were joined to the polygon attribute table of the dissolved boundary product creating the federal form of NWBD attribution. Process_Date: 20050317 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gina Beale Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 0297 Process_Step: Process_Description: Projected - Cover of sixth order units was projected to Geographic NAD83 to meet compliance standards. Process_Date: 20050317 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gina Beale Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 0297 Process_Step: Process_Description: Draft Layer Created - a coverage and shapefile of the VA NWBD with all related attribute files was created and made available to all. This draft layer included all edits known to be needed as of 28Feb06. Process_Date: 20060301 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gina Beale Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 0297 Process_Step: Process_Description: Final Border Unit Review and Attribution - copies of the NWBD of bordering states KY, TN, WV, and NC were obtained for final border linework and attribution review and editing. Only attribution edits were necessary for the VA layer. Required attribution corrections were issued to the other states. Only verbal agreements with EPA contractors could be made for final seamless attempts with MD. Process_Date: 20060417 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gina Beale, Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Final Version 1 Layer Created - a coverage of the VA NWBD with all related attribute files was created and made available to all. This layer included all edits needed to best assure a seamless product at this time. Process_Date: 20060616 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gina Beale Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 0297 Process_Step: Process_Description: Attribute Error Logging - about 20 attribute errors were reported by users. The nature of these errors led to a complete review of the coding of almost all polygon attributes. As a result, another 70 errors were found. Process_Date: 20070511 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Version 2 Created - 90 attribute errors were corrected in the base NWBD cover and in all related tables and files to create version 2 of the VA NWBD. Process_Date: 20070513 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Version 3 Created - 3 new polygons of existing units were added and 50 attribute values were changed in the base NWBD cover and in all related tables to maintain a seamless NWBD across the NC, WV, and MD border and meet other agreed upon corrections, thus creating version 3 of the base state form. Process_Date: 20081106 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Version 3 Derivative Layers Created - programs were run to create the federal layer and the 5th and 6th order central office layers from the various tables of the normalized base form. Process_Date: 20081107 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Version 4 Created - a few attribute values were changed in the base NWBD cover and in some related tables. Some minor linework modifications were made to maintain a seamless NWBD across the NC, and WV border. Process_Date: 20090910 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: Process_Description: Meta_ID: VA04 Version 4 Derivative Layers Created - programs were run to create the federal layer and the 5th and 6th order central office layers from the various tables of the normalized base form. Process_Date: 20090915 - 20110120 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA DCR-DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Process_Step: META_ID: VA06 Process_Description: The Line Mods, HU_Level, Linesource, DS codes and states were checked, the following meta ids were used for any updates. Source_Used_Citation_Abbreviation: Process_Date: 201109 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Label point Point_and_Vector_Object_Count: 1279 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 5676 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains Point_and_Vector_Object_Count: 1279 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.000018 Longitude_Resolution: 0.0000233 Geographic_Coordinate_Units: decimal degrees Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 Ellipsoid_Name: Geodetic Reference System 80 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257222101 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: VA_HU12.PAT Entity_Type_Definition: attributes of polygons in cover Entity_Type_Definition_Source: ESRI Attribute: Attribute_Label: AREA Attribute_Definition: area of polygon in square coverage units Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Although the values for AREA are in the domain of positive real numbers, they have no meaning because the coverage units is degrees. Attribute: Attribute_Label: PERIMETER Attribute_Definition: perimeter of polygon in coverage units Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Although the values for PERIMETER are in the domain of positive real numbers, they have no meaning because the coverage units is degrees. Attribute: Attribute_Label: VA_HU12# Attribute_Definition: internal feature number Attribute_Definition_Source: ESRI Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 1277 Attribute: Attribute_Label: VA_HU12-ID Attribute_Definition: user-assigned feature number Attribute_Definition_Source: ESRI Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 1276 Attribute: Attribute_Label: HUC_8 Attribute_Definition: unique 8 digit code of fourth order unit Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 02040303 Range_Domain_Maximum: 06010206 Attribute: Attribute_Label: HUC_10 Attribute_Definition: unique 10 digit code of fifth order unit Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0204030305 Range_Domain_Maximum: 0601020604 Attribute: Attribute_Label: HUC_12 Attribute_Definition: unique 12 digit code of sixth order unit Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 020403030501 Range_Domain_Maximum: 060102060403 Attribute: Attribute_Label: ACRES Attribute_Definition: area of this HUC_12 unit in Virginia Attribute_Definition_Source: VADCR Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 684864.13 Attribute_Units_of_Measure: acres Attribute: Attribute_Label: STATES Attribute_Definition: Abbreviations of all the states that sixth order unit HUC_12 falls within. Multiple states are separated by commas. Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: VA Enumerated_Domain_Value_Definition: Virginia Enumerated_Domain_Value_Definition_Source: USPS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: MD Enumerated_Domain_Value_Definition: Maryland Enumerated_Domain_Value_Definition_Source: USPS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: WV Enumerated_Domain_Value_Definition: West Virginia Enumerated_Domain_Value_Definition_Source: USPS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: TN Enumerated_Domain_Value_Definition: Tennessee Enumerated_Domain_Value_Definition_Source: USPS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: KY Enumerated_Domain_Value_Definition: Kentucky Enumerated_Domain_Value_Definition_Source: USPS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: NC Enumerated_Domain_Value_Definition: North Carolina Enumerated_Domain_Value_Definition_Source: USPS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: DC Enumerated_Domain_Value_Definition: District of Columbia Enumerated_Domain_Value_Definition_Source: USPS Attribute: Attribute_Label: NCONTRB_A Attribute_Definition: Areas within sixth order unit HUC_12 that are non-contributing to the outflow of the unit. Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 0 Attribute_Units_of_Measure: acres Attribute: Attribute_Label: HU_10_DS Attribute_Definition: Either the unique 10 digit code of the fifth order unit which is receiving the majority of the flow from unit HUC_10, or "OCEAN". If any state names appear in this field they are temporary place holders awaiting completion of unit coding in that state. Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0204030306 Range_Domain_Maximum: 0601020604 Attribute: Attribute_Label: HU_10_NAME Attribute_Definition: English name that uniquely identifies the fifth order unit HUC_10. Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Unrepresentable_Domain: Watershed names consist of the names of major water features within the watershed beginning with the least prominent feature and continuing until the unit name is unique within its fourth order unit. Attribute: Attribute_Label: HU_10_MOD Attribute_Definition: Identifiers of modifications to natural overland flow within the fifth order unit HUC_10. Multiple modifiers may apply. Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: KA Enumerated_Domain_Value_Definition: karst Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: DM Enumerated_Domain_Value_Definition: dam at outlet or HU boundary Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: RS Enumerated_Domain_Value_Definition: a reservoir influences the HU boundary Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: UA Enumerated_Domain_Value_Definition: urbanization influences the HU boundary Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: IT Enumerated_Domain_Value_Definition: interbasin transfer Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: DD Enumerated_Domain_Value_Definition: drainage ditch Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: MA Enumerated_Domain_Value_Definition: mining activity Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: OT Enumerated_Domain_Value_Definition: other Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: NM Enumerated_Domain_Value_Definition: no modifications Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute: Attribute_Label: HU_10_TYPE Attribute_Definition: hydrologic unit type for fifth order unit HUC_10 Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: S Enumerated_Domain_Value_Definition: Standard units - mostly land with a single outlet point. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: F Enumerated_Domain_Value_Definition: Frontal units along ocean, bay, and large lake shorelines that usually have more than one outlet. Predominantly land but may include some water near the outlet(s). Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: W Enumerated_Domain_Value_Definition: Water units - composed of at least 70% water, which includes mudflats. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: M Enumerated_Domain_Value_Definition: Multiple outlet units - those with more than one outlet, excluding frontal and water units. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: U Enumerated_Domain_Value_Definition: Unclassified units - those that cannot be defined using list of approved types. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute: Attribute_Label: HU_12_DS Attribute_Definition: Either the unique 12 digit code of the sixth order unit which is receiving the majority of the flow from unit HUC_12, or "OCEAN". Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 020403030503 Range_Domain_Maximum: 060102060306 Attribute: Attribute_Label: HU_12_NAME Attribute_Definition: English name that uniquely identifies the sixth order unit HUC_12. Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Unrepresentable_Domain: Watershed names consist of the names of major water features within the watershed beginning with the least prominent feature and continuing until the unit name is unique within its fifth order unit. Attribute: Attribute_Label: HU_12_MOD Attribute_Definition: Identifiers of modifications to natural overland flow within the sixth order unit HUC_12. Multiple modifiers may apply. Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: KA Enumerated_Domain_Value_Definition: karst Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: DM Enumerated_Domain_Value_Definition: dam at outlet or HU boundary Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: RS Enumerated_Domain_Value_Definition: a reservoir influences the HU boundary Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: UA Enumerated_Domain_Value_Definition: urbanization influences the HU boundary Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: IT Enumerated_Domain_Value_Definition: interbasin transfer Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: DD Enumerated_Domain_Value_Definition: drainage ditch Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: MA Enumerated_Domain_Value_Definition: mining activity Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: OT Enumerated_Domain_Value_Definition: other Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: NM Enumerated_Domain_Value_Definition: no modifications Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute: Attribute_Label: HU_12_TYPE Attribute_Definition: hydrologic unit type for sixth order unit HUC_12 Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: S Enumerated_Domain_Value_Definition: Standard units - mostly land with a single outlet point. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: F Enumerated_Domain_Value_Definition: Frontal units along ocean, bay, and large lake shorelines that usually have more than one outlet. Predominantly land but may include some water near the outlet(s). Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: W Enumerated_Domain_Value_Definition: Water units - composed of at least 70% water, which includes mudflats. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: M Enumerated_Domain_Value_Definition: Multiple outlet units - those with more than one outlet, excluding frontal and water units. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: U Enumerated_Domain_Value_Definition: Unclassified units - those that cannot be defined using list of approved types. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute: Attribute_Label: HU_10_GNIS# Attribute_Definition: GNIS feature numbers for hydrographic features in the fifth order unit. Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Codeset_Domain: Codeset_Name: Geographic Names Information System Codeset_Source: U.S. Board on Geographical Names Attribute: Attribute_Label: HU_12_GNIS# Attribute_Definition: GNIS feature numbers for hydrographic features in the sixth order unit. Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Codeset_Domain: Codeset_Name: Geographic Names Information System Codeset_Source: U.S. Board on Geographical Names Attribute: Attribute_Label: META_ID Attribute_Definition: version indicator Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: VA01 Enumerated_Domain_Value_Definition: Polygon attributes set at the time of initial layer completion (2006). Enumerated_Domain_Value_Definition_Source: VADCR Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: VA02 Enumerated_Domain_Value_Definition: Polygons with revised attributes in the creation of version 2 of the VA NWBD in May 2007. Enumerated_Domain_Value_Definition_Source: VADCR Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: VA03 Enumerated_Domain_Value_Definition: New polygons or polygons with revised attributes in the creation of version 3 of the VA NWBD in Sept and Oct 2008. Enumerated_Domain_Value_Definition_Source: VADCR Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: VA04 Enumerated_Domain_Value_Definition: New polygons or polygons with revised attributes in the creation of version 4 of the VA NWBD in Aug and Sept 2009. Enumerated_Domain_Value_Definition_Source: VADCR Detailed_Description: Entity_Type: Entity_Type_Label: VA_HU12.AAT Entity_Type_Definition: attributes of arcs in cover Entity_Type_Definition_Source: ESRI Attribute: Attribute_Label: FNODE# Attribute_Definition: internal number of from-node Attribute_Definition_Source: ESRI Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 2664 Attribute: Attribute_Label: TNODE# Attribute_Definition: internal number of to-node Attribute_Definition_Source: ESRI Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 2665 Attribute: Attribute_Label: LPOLY# Attribute_Definition: internal number of polygon to the left of arc Attribute_Definition_Source: ESRI Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 1279 Attribute: Attribute_Label: RPOLY# Attribute_Definition: internal number of the polygon to the right of arc Attribute_Definition_Source: ESRI Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 1279 Attribute: Attribute_Label: LENGTH Attribute_Definition: length of arc in cover units Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Although the values for LENGTH are in the domain of positive real numbers, they have no meaning because the coverage units is degrees. Attribute: Attribute_Label: VA_HU12# Attribute_Definition: internal feature number Attribute_Definition_Source: ESRI Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 4670 Attribute: Attribute_Label: VA_HU12-ID Attribute_Definition: user-assigned feature number Attribute_Definition_Source: ESRI Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 12914 Attribute: Attribute_Label: HU_LEVEL Attribute_Definition: lowest level of hydrologic units using this arc Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 6 Attribute: Attribute_Label: LINESOURCE Attribute_Definition: a code defining base map source of linework Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: DRG24 Enumerated_Domain_Value_Definition: Delineated from 1:24,000 Digital Raster Graphics of USGS quads. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: BATH40 Enumerated_Domain_Value_Definition: Interpreted from NOAA 1:40,000 scale bathymetric charts. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: ORTHO12 Enumerated_Domain_Value_Definition: Interpreted from 1:12,000 scale Ortho-imagery. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: TIGER Enumerated_Domain_Value_Definition: Interpreted from 1:100,000 scale TIGER files. Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: OTH Enumerated_Domain_Value_Definition: other Enumerated_Domain_Value_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute: Attribute_Label: META_ID Attribute_Definition: version indicator Attribute_Definition_Source: Federal standards for delineations of hydrologic units (Oct 2004). Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: VA01 Enumerated_Domain_Value_Definition: Arc linework and attributes set at the time of initial layer completion (2006). Enumerated_Domain_Value_Definition_Source: VADCR Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: VA02 Enumerated_Domain_Value_Definition: Arc attributes revised in the creation of version 2 of the VA NWBD in May 2007. Enumerated_Domain_Value_Definition_Source: VADCR Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: VA03 Enumerated_Domain_Value_Definition: Arc linework and/or attributes revised in the creation of version 3 of the VA NWBD in Sept and Oct 2008. Enumerated_Domain_Value_Definition_Source: VADCR Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: VA04 Enumerated_Domain_Value_Definition: Arc linework and/or attributes revised in the creation of version 4 of the VA NWBD in Aug and Sept 2009. Enumerated_Domain_Value_Definition_Source: VADCR Overview_Description: Entity_and_Attribute_Overview: The delineated hydrologic units are represented in the dataset as closed polygons. Boundaries are representative of ridge lines or, where there is little topographic difference, the imagined line along which water on either side flows off into different immediate streams or other bodies of water. The polygons/units are coded with the official 10 and 12 digit codes. Entity_and_Attribute_Detail_Citation: This metadata file, section Entity_and_Attribute_Information, compound element Detailed_Description. Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Steve Nechero Contact_Organization: U.S. Department of Agriculture Contact_Address: Address_Type: mailing address Address: 501 W. Felix St., Bldg 23 City: Ft. Worth State_or_Province: Texas Postal_Code: 76115 Country: USA Contact_Voice_Telephone: 817 509 3336 Contact_Electronic_Mail_Address: Steven.Nechero@ftw.usda.gov Resource_Description: NWBD of Virginia Distribution_Liability: No warranty expressed or implied is made by the USDA regarding the utility of the data on any system, nor shall the act of distribution constitute any such warranty. Neither the USDA 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 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 Communication at (202) 720-5881 (voice) or (202) 720-7808 (TDD). Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: ARC/INFO export file of cover Format_Version_Number: 9.2 File_Decompression_Technique: "uncompress" on unix, extract in Windows XP, or use WinZip. Transfer_Size: 6.9 MB compressed, 20.98 MB as uncompressed export Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://www.ftw.nrcs.usda.gov/nsdi_node.html Access_Instructions: local area network Offline_Option: Offline_Media: CD-ROM Recording_Format: ISO 9660 Level 1 Fees: an administrative charge of $50 for a CD-ROM that contains this data set Ordering_Instructions: call or write Turnaround: 10 working days Metadata_Reference_Information: Metadata_Date: 20050311 Metadata_Review_Date: 20090916 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Huber Contact_Organization: VA Dept. of Conservation & Recreation - DSWC Contact_Address: Address_Type: mailing and physical address Address: 203 Governor Street, Suite 206 City: Richmond State_or_Province: Virginia Postal_Code: 23219-2094 Country: USA Contact_Voice_Telephone: 804 371 7484 Contact_Facsimile_Telephone: 804 371 2630 Contact_Electronic_Mail_Address: karl.huber@dcr.virginia.gov Hours_of_Service: 0900-1800 Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Access_Constraints: none