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Address points mark the location of each addressable structure and its access point. The access point is the place where a driveway intersects the road. The building point is where the structure is located. An addressable structure is one where people live, work, or gather. A 1 to 5-digit number designates an address. Purpose: The access point is used to assign an address to the structure. Addresses are also assigned to assist in the provision of emergency services; they can be queried at all Fire and Rescue stations and by E-911 dispatchers. Supplemental Information: Data are stored in the corporate ArcSDE Geodatabase as a feature class. The coordinate system is Virginia State Plane (North), Zone 4501, datum NAD83 HARN. Maintenance and Update Frequency: Daily 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.

Data Owner: Office of Mapping and Geographic Information

WebLogis, Loudoun County's Online Mapping System. Provides access to the County’s Enterprise Geographic Information System data layers.

More MetadataThis Water Well layer was created in March 2010 to provide an easily accessiable spatial database of water wells only. It also provides additional attribute information on Status, Depth, etc.The original water well & pollution source layer was developed in 1988 by the County’s Environmental Health Department. Records were entered into a database from 40 years of historical paper files, which exhibited a wide range of completeness and accuracy. This was an on-going process until early 1996 at which time the layer was no longer maintained. In late 2000, the Department of Building and Development began a process of updating the layer by entering data from the permit files, which had accumulated since 1996.

DATA MAINTENANCE / UPDATE FREQUENCY: ANNUALLY - DATA LAST UPDATED BASED ON 2023 IMAGERY More MetadataTree Points are a base map data layer derived by automated processes and processed for cartographic representation at 1:2400 scale. The point features represent any isolated, visible, single standing tree as seen from above and are mapped to National Map Accuracy Standards (NMAS). These may be orchards, single specimen trees or rows of landscape tree features that together do not comprise a polygonal forest feature.

Loudoun County annually obtains leaf-off, aerial imagery in the spring. Since 2004, the County has utilized this imagery to support the development of an annual digital orthophoto base. In 2021, the imagery was captured with a Vexcel Ultracam Eagle digital camera, in 4-band (R,G,B, and NIR) format. These files contain 1-foot ground-resolution, 8-bit, 4-band orthorectified aerial image map products in GeoTIFF version 6.0 file format. GeoTIFF files are uncompressed raster images complete with TFW coordinate information. The aerial imagery project encompasses the entire land area of the County of Loudoun, VA. Images were flown during leaf-off conditions and cover 5000' by 5000' and are tiled according to the VBMP 200-scale gridding schema (Virginia Geographic Information Network)."March 2021 Photography flown by the Sanborn Map Company, Colorado Springs, CO." "Digital Orthophotography compiled by Sanborn Map Company, Colorado Springs, CO"

Loudoun County, Virginia Boundary

More MetadataThis layer identifies existing parcels within Loudoun County and their current Land Use. The existing structures data source is Loudoun County VA, Office of Mapping & Geographic Information's (OMAGI) addressable structure layer for all of Loudoun County, VA. All residential uses, which includes Single Family, Multi-Family and Group Quarter uses, are specified and existing Commercial structures (Offices, Retail, Medical Offices, Data Centers, etc.) are combined into a single Non-Residential use. The other uses specifically identified are HOA (Home owner Association owned parcels), Miscellaneous (no employment generating), and Multi-Use (2 different uses), and Vacant (parcel with no land use).

The stormwater pipes and culverts data is comprised of lines. The pipes and culverts are the man-made structures composed of concrete, metal and plastic used to convey stormwater from catch basins and ponds to the natural drainage ways and swales that eventually discharge to creeks and streams. The pipes and culverts data was collected primarily in eastern Loudoun in the more urbanized portions of the County and was collected in the field using GPS instrumentation. At least 95% of the locational data for the pipes and culverts is accurate to within 1 meter or less. Pipes and culverts are named and digitized in the direction of water flow.

Loudoun County annually obtains leaf-off, aerial imagery in the spring. Since 2004, the County has utilized this imagery to support the development of an annual digital orthophoto base.

Geospatial data about Loudoun County, Virginia Topography (4ft). Export to CAD, GIS, PDF, CSV and access via API.

More MetadataPlanar Index of Loudoun County is used primarily for locator reference and establishes the first 3 digits in the MCPI number for parcels. This information can also be known as Map, Sheet, or Tile number in other data sets.The index coverage contains approximately 690 polygons which coincide with Loudoun County's GIS library tile system. Digital Data orders and associated maps are available to the extent of any individual tile as well as county wide. Each tile is designated with a unique ID number that is used in GIS data orders to identify the area of interest.

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This layer contains the geographical boundaries of the Metropolitan Washington Council of Government's Traffic Analysis Zones (TAZ) of Loudoun County, Virginia. TAZs are designed to be relatively homogeneous units with respect to population, economic, and transportation characteristics. These TAZ boundaries were delineated by Loudoun County Government and adopted by the Metropolitan Washington Council of Governments.

Loudoun County Parcel X,Y coordinates table. Available in Latitude and Longitude decimal degrees and Virginia State Plane North.

This data set contains the 1937 aerial imagery for the majority of Loudoun County, VA. It is composed of United States Farm Service Agency (USDA FSA) hardcopy imagery, which were scanned, georeferenced, and mosaicked by Loudoun County OMAGI to produce digital representations. This aerial imagery is at a much larger scale than the County's other Historical Raster image (1957). There are only 200 photos that cover Loudoun County for the 37 imagery, as opposed to 700 for the 57.