Summary Statement:

This metadata summary applies exclusively to the data as it appears in this Loudoun County intranet/internet mapping application. To see the fully FGDC compliant version of this metadata click here

Abstract:

Elevation contours are a base map data layer derived by automated processes and processed for cartographic representation at 1:2400 scale. The line features represent the 4' contour intervals, and 20' index contours as mapped from above and are mapped to National Map Accuracy Standards (NMAS).

Purpose:

Typically contours are used in both the private and public sectors for planning land management applications such as :

  • Land development
  • Site design
  • Agricultural planning
  • Utilities
  • Floodplain analysis
  • Route location
  • Emergency response
  • FEMA mapping
  • Storm water management
  • Disaster preparedness and response
  • Water supply and quality
  • Land transportation and safety

    • Supplemental Information:

    This new 4ft topographic dataset, which was received in 2010 through agreement with Virginia Geographic Information Network (VGIN), is the beginning of the County's changing in mapping topographic contours. All future updates will use 4ft contour intervals.

    OMAGI updates all base map data via a photogrammetric process, using aerial imagery that is flown yearly in phases. A different portion of the County is updated each year with the base map maintenance services contract, depending upon development patterns and update funding. See "Lineage" section, in the full FGDC version, for the list of extents for each Phase area, which are listed as Data Sources. For a map of the most recent reviews and updates within the county, please click here.

    Use Constraints:

    Chapter 54.1-402 of the Code of Virginia.
    "Any determination of topography or contours, or any depiction of physical improvements, property lines or boundaries is for general information only and shall not be used for the design, modification, or construction of improvements to real property or for flood plain determination."

    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 are intended for use at 1:2400 scale or smaller.

    Maintenance and Update Frequency:

    Annually

    Completeness Report:

    Initial County-wide mapping project that will be updating in future years based on the previously mentioned development patterns and update funding. The entire County is reviewed prior to any update.

    Data Owner:

    Office of Mapping and Geographic Information