| Town Wells of Lovettsville, VA (2008) | |
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Data format: SDE Feature Class File or table name: GISDBB.GISBROW.LVILLE_TOWN_WELLS_POINT Coordinate system: Lambert Conformal Conic Theme keywords: utillitiesCommunication, wells, water, water supply |
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Abstract:
This feature class identifies all of the town owned water wells in Lovettsville, VA. The town derived ID number of each well is included in the data's attributes. |
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Metadata elements shown with blue text are defined in the Federal Geographic Data Committee's (FGDC) Content Standard for Digital Geospatial Metadata (CSDGM). Elements shown with green text are defined in the ESRI Profile of the CSDGM. Elements shown with a green asterisk (*) will be automatically updated by ArcCatalog. ArcCatalog adds hints indicating which FGDC elements are mandatory; these are shown with gray text.
This feature class identifies all of the town owned water wells in Lovettsville, VA. The town derived ID number of each well is included in the data's attributes.
Town wells were collected at the request of the town of Lovettsville for town mapping purposes. They can be used in town related planning projects to map the present infrastructure of the town.
Data are stored in the corporate ArcSDE Geodatabase as a point feature class. The coordinate system is Virginia State Plane (North), Zone 4501, datum NAD83 HARN (vertical datum, if applicable, NAVD88), US Survey foot units.
publication date
Every reasonable effort has been made to assure the accuracy of these data. Loudoun County, Virginia does not assume any liability arising from the use of these data. These data are provided without warranty of any kind, expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular service. Reliance on these data is at the risk of the user. These data were generated for use by Loudoun County and are available to the public. These data are intended for use at 1:2400 scale or smaller. Acknowledgement of Loudoun County would be appreciated in products derived from this data.
1 Harrison Street SE, 2nd Floor
MS 65
Retention of attribute accuracy throughout the GPS data file to geodatabase feature class coversion process was ensured by a manual QA/QC programmatic check. To meet satisfactory QA/QC requirements the input data file and output feature class must have, on a record by record basis, identical attribution to all the user-defined attribution.
Topologically clean
Features may have been eliminated or generalized due to scale and intended use. To assist Loudoun County, Virginia in the maintenance of the data, please provide any information concerning discovered errors, omissions, or other discrepancies found in the data.
Retention of coordinate accuracy throughout the GPS data file to geodatabase feature class conversion process ensured by following a specific differential correction process with GPS Pathfinder software. Base files for differential correction are downloaded from a Continuously Operating Reference Station (CORS) at Gaithersburg, MD. The GPS data files are differentially corrected using the Standard Automatic Code Correction Process. This process results in sub-meter accuracy for corrected data files; predominately at a 0.5-1 meter distance, with some files at 30-50 cm & 1-2 meters. The corrected files are then exported using the County's standary projection & copied into the Lovettsville PGDB & appropriate feature class. To meet satisfactory QA/QC requirements the input GPS file and output feature class must have the same record total, and on a record by record basis, same location as corrected GPS files. Features may be spatially adjusted using 2007 digital photography if higher sub-meter accuracy places them incorrectly.
Request for assistance in data collection by Keith Markel, Lovettsville Town Manager in January 2008
GPS collection of all existing town wells in the town of Lovettsville with Trimble GPS unit. A GPS data dictionary was created and used to collect targeted attribute values for each feature type collected.
GPS data downloaded from unit & then differentially corrected in GPS Pathfinder using base files from CORS at Gaithersburg, MD. The Standard Automatic Code Correction process was used to correct the data, which resulted in a predominately sub-meter accuracy of .5 to 1 meters (1.5 to 3 feet). The differentially corrected data was then exported from Pathfinder as a sample shapefile & copied into the existing Lovettsville PGDB & corresponding feature class.
Internal feature number.
ESRI
ID number of well
Loudoun County
Source by which feature class was created or modified
Loudoun County
eature creation or modification date
Loudoun County
Feature geometry.
ESRI
Not for public distribution. Internal User ID of editor creating or modifying a feature
Loudoun County
TW_UPD_SOURCE: Source that created or modified feature class
Code Description 0 Undetermined 1 Legacy 2 County 3 Contract
1 Harrison Street SE, 2nd Floor
MS 65
Every reasonable effort has been made to assure the accuracy of these data. Loudoun County, Virginia does not assume any liability arising from the use of these data. These data are provided without warranty of any kind, either expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular service. Reliance on these data is at the risk of the user.
ESRI Personal Geodatabase Feature Class
ESRI Shapefile
AutoCad Digital Exchange File
Size limit: 4.5 GB. Visit our website at: http://www.loudoun.gov/omagi, click on "Loudoun County Mapping Documents & Order Forms." The "Forms" directory will lead you to custom & standard (countywide) data order forms. Hardcopy maps may also be available; please contact the Mapping Office Public Information Counter for more information regarding all data requests.
1 Harrison Street SE, 2nd Floor
MS 65