Document
NGDA theme(s)
Maintenance Authority
Scope
Geodetic control surveys are usually performed to establish the
basic positional framework from which supplemental surveying and
mapping are performed. Geodetic control surveys are distinguished by
use of redundant, interconnected, permanently monumented control points
that comprise the National Spatial Reference System (NSRS) or are often
incorporated into NSRS. Geodetic control surveys are performed to far
more rigorous accuracy and quality assurance standards than those for
local control surveys for general engineering, construction, or
topographic mapping purposes. Geodetic control surveys included in NSRS
meet automated data recording, submittal, project review, and least
squares adjustment requirements established by the Federal Geodetic
Control Subcommittee (FGCS).
Purpose
This document provides a common methodology for creating datasets
of horizontal coordinate values and vertical coordinate values for
geodetic control points represented by survey monuments, such as brass
disks and rod marks. It provides a single data structure for relating
coordinate values obtained by one geodetic survey method (for example,
a classical line-of-sight traverse) with coordinate values obtained by
another geodetic survey method (for example, a Global Positioning
System geodetic control survey).
Comments
August 2014: this standard is currently under revision