U.S. flag An official website of the United States government.
Official websites use .gov

A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS

A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

i

Control leveling

Public Domain
File Language:


Select the Download button to view the document
Please click the download button to view the document.

Details

  • Personal Author:
    Whalen, Charles T.
  • Corporate Authors:
  • NOAA Program & Office:
  • Description:
    Control leveling is used to determine precise elevations of bench marks (monumented points) above or below a reference surface called a datum. The National Geodetic Survey (NGS) of the

    National Ocean Survey (NOS), formerly the U. S. Coast and Geodetic Survey (USC&GS), now a component of the National Oceanic and Atmospheric Administration, determines elevations in meters above or below the National Geodetic Vertical Datum of 1929.

    Bench marks are located at distances of about 1.6 km along railroads and highways in the United States to form level lines. These level lines form a net of closed loops. The present program for

    development of the fundamental vertical control net calls for first-order lines at approximately 160-km intervals with a subdivision of second-order lines spaced at 40 to 80 km. In certain areas of intense development, the net is again subdivided by second-order lines spaced at 8 to 16 km. The current net consists of 370,000 km of first- and second-order leveling.

  • Keywords:
  • Series:
    NOAA technical report NOS NGS ; 73-8
  • Document Type:
    Technical Report
  • Rights Information:
    Public domain
  • Compliance:
    Library
  • Main Document Checksum:
    urn:sha256:93d909e31e8f5e148ef685db6360aad76d1a7dd5dae18a635736b2e782736de0
  • Download URL:
  • File Type:
    Filetype[PDF - 62.86 MB ]
PREVIOUS
File Language:
ON THIS PAGE
Details
The NOAA IR serves as an archival repository of NOAA-published products including scientific findings, journal articles, guidelines, recommendations, or other information authored or co-authored by NOAA or funded partners. As a repository, the NOAA IR retains documents in their original published format to ensure public access to scientific information.
BACK TO TOP