METRIC DESIGN GUIDE
Civil/Surveying
The two primary Federal agencies involved in the production of survey information for
public use are the National Geodetic Survey (NGS) and the U.S. Geological Survey
(USGS). The databases for these two agencies are metric.
NGS, which maintains a database of hundreds of thousands of horizontal and vertical
survey control points on which U.S. surveys are based, has been metric since 1983.
USGS, which produces topographic maps of terrain elevations, has digitally mapped the
U.S. surface. The ground distance between each pair of digitized points is 30 meters.
Survey and mapping data necessary to do metric design and construction in the United
States are available. Most states have adopted metric in their state plane coordinate
systems.
The following information has been used on site plans and topographic maps.
Contour intervals utilize either 1.000, 0.500, or 0.250 m as contour intervals, depending on
site slope.
Elevation measurements are given in m.
Benchmark elevations are converted from feet to m.
Examples:
Benchmark is 314.15 feet. Convert to 9 .753m.
5
Sample Contour Lines:
____________
106. 0 ____________
____________
105. 5 ____________
PBS-PQ260
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