Hydro lines (arcs) in Fairfax County, Virginia, USA as retrieved from the Fairfax County GIS website on 15 March 2011. Data was exported on 14 April 2008. Per communication with office staff, data on that page is in the public domain.

Loudoun County was founded in 1757. Loudoun's boundary with Maryland is the mean low water mark of the Potomac River on the Virginia side; it has not been surveyed. Loudoun's boundary with Prince William County is the Bull Run Creek. The border has not been modified for recent surveys. Individual plats along the Potomac and Bull Run Rivers have not resulted in a change in the border along those rivers- since measurements of the waters edge vary seasonally and the County Boundary needs to be seamless and constant. Many decades ago tax commissioners from surrounding jurisdictions assigned parcels to one jurisdiction or another rather than splitting parcels. Currently there is a mix of parcels split by a County Boundary, parcels taxed entirely in Loudoun, and portions of parcels within the County but taxed by another jurisdiction. The Office of the Commissioner of the Revenue dictates how these parcels are taxed, as do other jurisdictions. In 1957, the boundary with Fairfax County was re-established and finalized. The boundary with Fauquier County was surveyed and monumented in 1966. The boundary with Clarke County was surveyed in 1989, and the boundary survey with Jefferson County West Virginia was completed in 1998. The West Virginia, Fairfax, Fauquier, and Clarke boundary arcs were created by generating coverages from the monument coordinates using the generate command.

Loudoun County was founded and surveyed in 1757. Loudoun's boundary with Maryland is the mean low water mark of the Potomac River on the Virginia side; it has not been surveyed. Loudoun's boundary with Prince William County is the Bull Run Creek. The border has not been modified for recent surveys. Individual plats along the Potomac and Bull Run Rivers have not resulted in a change in the border along those rivers- since measurements of the waters edge vary seasonally and the County Boundary needs to be seamless and constant. Many decades ago tax commissioners from surrounding jurisdictions assigned parcels to one jurisdiction or another rather than splitting parcels. Currently there is a mix of parcels split by a County Boundary, parcels taxed entirely in Loudoun, and portions of parcels within the County but taxed by another jurisdiction. The Assessor's office dictates how these parcels are taxed, as do other jusidictions. In 1957, the boundary with Fairfax County was re-established and finalized. The boundary with Fauquier County was surveyed and monumented in 1966. The boundary with Clarke County was surveyed in 1989, and the boundary survey with Jefferson County West Virginia was completed in 1998. The West Virginia, Fairfax, Fauquier, and Clarke boundary arcs were created by generating coverages from the monument coordinates using the generate command.

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Edge refers to the linear topological primitives that make up MTDB. The All Lines Shapefile contains linear features such as roads, railroads, and hydrography. Additional attribute data associated with the linear features found in the All Lines Shapefile are available in relationship (.dbf) files that users must download separately. The All Lines Shapefile contains the geometry and attributes of each topological primitive edge. Each edge has a unique TIGER/Line identifier (TLID) value.

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) System (MTS). The MTS represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Edges refer to the linear topological primitives that make up the MTS. The All Lines shapefile contains linear features such as roads, railroads, and hydrography. Additional attribute data associated with the linear features found in the All Lines shapefile are available in relationship (.dbf) files that users must download separately. The All Lines shapefile contains the geometry and attributes of each topological primitive edge. Each edge has a unique TIGER/Line identifier (TLID) value.

This layer contains data defining the exterior boundaries of subdivided land within Fairfax County, Virginia. The Subdivision layer was created to depict subdivided land areas defined by recorded documents (plats) for the County of Fairfax. The polygons portrayed on this layer define the second portion of the County's Parcel Identification Numbering system (Map / Subdivision / Block / Parcel). Information portrayed on this layer was initially derived from the ink-on-mylar property maps maintained by the County since the early 1960s.For more information go to the Geospatial Property Data Guide.Contact: Fairfax County Department of Information Technology GIS DivisionData Accessibility: Publicly AvailableUpdate Frequency: DailyLast Revision Date: 1/1/2000Creation Date: 1/1/2000Feature Dataset Name: GISMGR.PARCELSLayer Name: GISMGR.SUBDIVISIONS

Loudoun County, Virginia Boundary

Fairfax County Supervisor (Magisterial) Districts.

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Edge refers to the linear topological primitives that make up MTDB. The All Lines Shapefile contains linear features such as roads, railroads, and hydrography. Additional attribute data associated with the linear features found in the All Lines Shapefile are available in relationship (.dbf) files that users must download separately. The All Lines Shapefile contains the geometry and attributes of each topological primitive edge. Each edge has a unique TIGER/Line identifier (TLID) value.

Stormwater easements (ex: storm drainage, storm sewer, floodplain) as captured from recorded plats using coordinate geometry (COGO) capture method. All easements are contained within the Fairfax County boundary.

This layer contains data defining the exterior boundaries of subdivided land within subdivisions in Fairfax County, Virginia. The Block layer was created to depict subdivided land areas within subdivisions defined by recorded documents (plats) for the County of Fairfax. The polygons portrayed on this layer define the third portion of the County's Parcel Identification Numbering system (Map / Subdivision / Block / Parcel). Blocks are indicated on the property maps using a number within a single circle and boundaries that have heavy dashed lines. Information portrayed on this layer was initially derived from the ink-on-mylar property maps maintained by the County since the early 1960s.For more information go to the Geospatial Property Data Guide.Contact: Fairfax County Department of Information Technology GIS DivisionData Accessibility: Publicly AvailableUpdate Frequency: DailyLast Revision Date: 1/1/2000Creation Date: 1/1/2000Feature Dataset Name: GISMGR.PARCELSLayer Name: GISMGR.BLOCKS

The voting precincts within Fairfax County.

This layer contains data defining the exterior boundaries of land under common ownership, typically within condominium properties within Fairfax County, Virginia. The common area layer was created to depict these areas of land that do not actually have parcel identification numbers. These areas of land are owned by a group of properties that lie within the common area. Information portrayed on this layer was initially derived from the ink-on-mylar property maps maintained by the County since the early 1960s. Contact: Fairfax County Department of Information Technology GIS DivisionData Accessibility: Publicly AvailableUpdate Frequency: DailyLast Revision Date: 1/1/2000Creation Date: 1/1/2000Feature Dataset Name: GISMGR.PARCELSLayer Name: GISMGR.COMMON_AREAS

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. The Feature Names Relationship File (FEATNAMES.dbf) contains a record for each feature name and any attributes associated with it. Each feature name can be linked to the corresponding edges that make up that feature in the All Lines Shapefile (EDGES.shp), where applicable to the corresponding address range or ranges in the Address Ranges Relationship File (ADDR.dbf), or to both files. Although this file includes feature names for all linear features, not just road features, the primary purpose of this relationship file is to identify all street names associated with each address range. An edge can have several feature names; an address range located on an edge can be associated with one or any combination of the available feature names (an address range can be linked to multiple feature names). The address range is identified by the address range identifier (ARID) attribute, which can be used to link to the Address Ranges Relationship File (ADDR.dbf). The linear feature is identified by the linear feature identifier (LINEARID) attribute, which can be used to relate the address range back to the name attributes of the feature in the Feature Names Relationship File or to the feature record in the Primary Roads, Primary and Secondary Roads, or All Roads Shapefiles. The edge to which a feature name applies can be determined by linking the feature name record to the All Lines Shapefile (EDGES.shp) using the permanent edge identifier (TLID) attribute. The address range identifier(s) (ARID) for a specific linear feature can be found by using the linear feature identifier (LINEARID) from the Feature Names Relationship File (FEATNAMES.dbf) through the Address Range / Feature Name Relationship File (ADDRFN.dbf).

Boundaries for Fairfax County High School Attendance

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. The All Roads Shapefile includes all features within the MTDB Super Class "Road/Path Features" distinguished where the MAF/TIGER Feature Classification Code (MTFCC) for the feature in MTDB that begins with "S". This includes all primary, secondary, local neighborhood, and rural roads, city streets, vehicular trails (4wd), ramps, service drives, alleys, parking lot roads, private roads for service vehicles (logging, oil fields, ranches, etc.), bike paths or trails, bridle/horse paths, walkways/pedestrian trails, stairways, and winter trails.

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Edge refers to the linear topological primitives that make up MTDB. The All Lines Shapefile contains linear features such as roads, railroads, and hydrography. Additional attribute data associated with the linear features found in the All Lines Shapefile are available in relationship (.dbf) files that users must download separately. The All Lines Shapefile contains the geometry and attributes of each topological primitive edge. Each edge has a unique TIGER/Line identifier (TLID) value.

This layer contains the boundaries of special tax areas as defined by the taxing authority of Fairfax County. These are special tax districts where additional fees are levied on the properties within the districts. For current tax rates on properties for each of the tax areas refer to this page: https://www.fairfaxcounty.gov/taxes/real-estate/tax-rates Contact: Fairfax County Department of Information Technology GIS DivisionData Accessibility: Publicly AvailableUpdate Frequency: DailyLast Revision Date: 1/1/2000Creation Date: 1/1/2000Feature Dataset Name: GISMGR.PARCELSLayer Name: GISMGR.SPECIAL_TAX_AREAS