Geodetic Ground Control Points
Keywords: Ground Monument, Station, GPS, Surveying
Published: 199904
Richmond GIS Layer Inventory
Contact Richmond GIS
  Abstract: Represents Geodetic Control Monuments/Network that conforms to Federal Geodetic Control Committee First Order Accuracy Standards for global positioning system horizontal networks. Produced by the Commonwealth of Virginia, Land Surveyor, 4-30-1999.
  Purpose: Geodetic Control Monuments are used by surveyors to locate stations that conform to industry accuracy standards. These ground monuments are used for geodetic control and referencing associated with the City's GIS base mapping projects, i.e. VBMP.
  Supplemental Information: The Ground Monumentation was provided/obtained during the City's original base mapping project in 1999, and has remained little changed in the interim, although a couple stations may have been added to the inventory, and those should be present in this data source. Physical Description of Stations: The stations consist of 3 1/4 inch diameter domed brass alloy disks set in 8 inch diameter concrete posts. The station disks are stamped "City of Richmond Geodetic Control Monument" with the station number and the year 1999. The concrete posts are cast-in-place, 36 inch in depth, adn contain a 5/8 inch diameter reinforcing bar 30 inch in length for stability. Reference and recovery data sheets are available on the City's web site:
  Custodian: Chul Chong
  Department: Public Works
  Position: GIS Engineer
  Address: 900 E Broad St, 7th Floor
  City: Richmond
  State: Virginia
  Zip Code: 23219
Time Period of Content
  Date: 199904
  Progress: Complete
  Update Frequency: None planned
Spatial Domain
  West Coordinate: -77.598979
  East Coordinate: -77.388597
  North Coordinate: 37.604715
  South Coordinate: 37.455268
Spatial Data Information
  Data Type: vector digital data
  Data Format: SDE Feature Class
  Data Projection: Lambert Conformal Conic
Access and Usage Information
  Access Constraints: none
  Use Constraints: All GIS layers and datasets are owned by the City of Richmond and can not be modified, re-distributed, and/or re-sold without a sub-licensing agreement. All guarantees of validity expire once a dataset leaves the City of Richmond firewall or physical premises. Acknowledgement of the City of Richmond GIS would be appreciated in products derived from these data.
Entity and Attribute Information
  Entity Name: vector.ric.base_GroundControl
  Entity Type: Feature Class
  Entity Count: 53