Survey Control

Purpose
In 2011, the City of Falls Church Department of Public Works contracted with a surveying firm to establish 30 new survey control monuments in accordance with Blue Book procedures by National Geodetic Surveys (NGS).  The monuments were accepted into the NGS database in January of 2012.

The new monumentation attained Future Generation Computer Systems (FGCS) Class C.
  • First order global positioning system (GPS) positional tolerances and RT-1 classification
  • For vertical control, the monumentation reached FGCS
  • Third order specifications level with a Leica digital level following NGS guidelines
Survey Control
Method
The method used was a modified approach that integrated the NGS Guidelines for Real Time v2.0.04 specifications and conventional GPS specifications published by NGS.
Each of the 30 survey monuments can be found in the National Geodetic Survey database. The Falls Church Control Cards are provided to assist in locating the new monuments.

The locations can also be found on the city's online Geographic Information System (GIS).