Election Precincts of Loudoun County, VA (2012)

Metadata also available as

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:: Loudoun County, VA, Department of Management and Financial Services
Publication_Date: 20120910
Title: Election Precincts of Loudoun County, VA (2012)
Geospatial_Data_Presentation_Form: vector digital data

Description:

Abstract:: This file contains the voting precincts. These precinct boundaries were last reviewed, updated, and adopted by the Board of Supervisors on November 15, 2011. The Department of Justice subsequently approved the precincts. Precincts are wholly contained within the Loudoun Board of Supervisors' election districts. The first digit of the three digit PR_Number (precinct number) identifies the precinct's local BOS election district.
Purpose:: Voting districts are established by the Loudoun County Board of Supervisors and Electoral Board for the purpose of conducting elections.
Supplemental_Information:: Data are stored in the corporate ArcSDE Geodatabase as a polygon feature class. The coordinate system is Virginia State Plane (North), Zone 4501, datum NAD83 HARN (vertical datum, if applicable, NAVD88), US Survey foot units.

Status:

Progress: Complete
Maintenance_and_Update_Frequency: As needed

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -77.963439
East_Bounding_Coordinate: -77.323973
North_Bounding_Coordinate: 39.326230
South_Bounding_Coordinate: 38.844263

Keywords:

Theme:

Theme_Keyword_Thesaurus: none; Employee generated
Theme_Keyword: election
Theme_Keyword: voting
Theme_Keyword: district
Theme_Keyword: precinct

Theme:

Theme_Keyword_Thesaurus: ISO 19115 Topic Categories
Theme_Keyword: location
Theme_Keyword: society

Place:

Place_Keyword_Thesaurus: none; Employee generated
Place_Keyword: Virginia
Place_Keyword: County
Place_Keyword: 51107
Place_Keyword: Loudoun

Access_Constraints: None

Use_Constraints:

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.

Point_of_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization:: Loudoun County, VA, Department of Management and Financial Services

Contact_Position: Demographer

Contact_Address:

Address_Type: mailing and physical
Address: MS 41
Address: 1 Harrison St
City: Leesburg
State_or_Province: VA
Postal_Code: 20175
Country: US

Contact_Voice_Telephone: (703) 777-0563

Hours_of_Service: 8:30-5:00 EST, M-F

Native_Data_Set_Environment:

Microsoft Windows Server 2008 Version 6.0 (Build 6002) Service Pack 2; ESRI ArcGIS 10.0.5.4400

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:: Retention of attribute accuracy throughout the personal geodatabase or shapefile to ArcSDE geodatabase feature class coversion process was ensured by a manual or automatic QA/QC programmatic check. To meet satisfactory QA/QC requirements the input coverage and output feature class must have, on a record by record basis, identical attribution when comparing all concatenated fields to all the user-defined attribution.

Logical_Consistency_Report: Topologically clean

Completeness_Report:

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.

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:: Retention of coordinate accuracy throughout the personal geodatabase or shapefile to ArcSDE geodatabase feature class conversion process was ensured by a manual or automatic QA/QC programmatic check. To meet satisfactory QA/QC requirements the input coverage and output feature class must have the same record total, and on a record by record basis, area, perimeter, and length differential of less than +/- 0.5%.

Lineage:

Source_Information:

Source_Citation:

Citation_Information:

Originator: U.S. Census Bureau
Publication_Date: 20100401
Title: 2010 Census SF1 block data

Type_of_Source_Media: onLine

Source_Citation_Abbreviation: 2010 Census SF1 block data

Source_Contribution:

The 2010 Census SF1 block data were the basis for deriving the demographic data.

Source_Information:

Source_Citation:

Citation_Information:

Originator: Loudoun County, VA
Publication_Date: 20120102

Type_of_Source_Media: hardcopy

Source_Contribution:

Loudoun County Department of Management and Financial Services is the source for population, housing units, household estimates.

Source_Information:

Source_Citation:

Citation_Information:

Title: Loudoun County GIS

Type_of_Source_Media: None

Source_Citation_Abbreviation: Loudoun County GIS

Source_Contribution:

Loudoun County Government GIS layers for Census Block & precinct line "adjustments"

Source_Information:

Source_Citation:

Citation_Information:

Originator: ESRI
Publication_Date: 20100111
Title: ESRI Tiger data

Type_of_Source_Media: None

Source_Citation_Abbreviation: ESRI Tiger data

Source_Contribution:

TIGER/Line files provided the foundation upon which census blocks were drawn. The 2010 Census blocks were the basis for devising the election district boundaries.

Process_Step:

Process_Description:: The precinct layer has the potential to be updated on a yearly basis as the County's population growth dictates. As precincts exceed their designated population amount, precincts are either split or merged with existing precincts.

Process_Step:

Process_Description:

The precinct boundaries are designated to follow physical features, natural features, and governmental units such as town boundaries. Census blocks are designated to follow these types of features as well. Census block shapefiles were downloaded from the U.S. Census Bureau. Overlaid the Census Bureau block shapefile with Loudoun County Government's detailed GIS layers to determine the actual location of the physical features, natural features, and governmental units such as town boundaries that the census blocks are designated to follow. Digitized block lines using Loudoun County Government's detailed GIS layers. Precinct boundaries that do not follow block boundaries were identified. The identified boundaries were digitized using Loudoun County Government's detailed GIS layers, and in doing so, census blocks were split into parts. Created the precinct layer by assigning the precinct name to each census block or census block split area and then spatially dissolving the census block with splits layer. The population, household, and housing unit totals were derived by summing U.S. Census Bureau 2010 Census block and census block split area totals. For split census blocks, the percentage of a blocks housing units that existed for the 2010 Census in the split area was determined using a combination of building permit, occupancy permit, and assessment data. This calculated percentage for a census block's split area was then multiplied by the population, household, and housing unit totals of the census block to derive the estimated population, household, and housing unit totals for the block split area.

Process_Date: 20120109

Process_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: Loudoun County Department of Management and Financial Services

Contact_Position: Demographer

Spatial_Data_Organization_Information:

Indirect_Spatial_Reference: Loudoun County

Direct_Spatial_Reference_Method: Vector

Point_and_Vector_Object_Information:

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains
Point_and_Vector_Object_Count: 84

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Map_Projection:

Map_Projection_Name: Lambert Conformal Conic

Lambert_Conformal_Conic:

Standard_Parallel: 38.03333333333333
Standard_Parallel: 39.2
Longitude_of_Central_Meridian: -78.5
Latitude_of_Projection_Origin: 37.66666666666666
False_Easting: 11482916.66666666
False_Northing: 6561666.666666666

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: coordinate pair

Coordinate_Representation:

Abscissa_Resolution: 0.00020833333333333297
Ordinate_Resolution: 0.00020833333333333297

Planar_Distance_Units:

Geodetic_Model:

Horizontal_Datum_Name: D North American 1983 HARN
Ellipsoid_Name: GRS 1980
Semi-major_Axis: 6378137.0
Denominator_of_Flattening_Ratio: 298.257222101

Entity_and_Attribute_Information:

Detailed_Description:

Entity_Type:

Entity_Type_Label: GISDBB.GISBROW.PRECINCT_POLY

Attribute:

Attribute_Label: PR_HHLDS2010

Attribute_Definition:

2010 households of the precinct. Households are occupied housing units.

Attribute_Definition_Source: Loudoun County