In Reply Refer To:
Mail Stop 415

April 18, 2011


SUBJECT: Policy on leveling procedures at streamgages and announcement of the publication Techniques and Methods Report Book 3, Section A19 “Levels at gaging stations.”

The Office of Surface Water (OSW) is pleased to announce the release of the U.S. Geological Survey (USGS) Techniques and Methods Report Book 3, Chapter A19 “Levels at gaging stations" by Terry A. Kenney. The report is available on-line at: . This report describes procedures that are now OSW policy and are required for running levels at streamgages. All personnel responsible for running levels at streamgages should become acquainted with the information provided in this report.

The report describes leveling procedures that should be used to ensure that streamgages are accurately set to the established gage datum. Differential leveling techniques are used to determine elevations for reference marks, reference points, all gages, and the water surface. The techniques presented in this report provide guidance on instruments and methods that ensure streamgage levels are run to the required precision and accuracy. A summary of leveling procedures contained in the report is as follows:

A summary of requirements and tolerances specified in Techniques and Methods Report Book 3, Chapter A19 is presented in Appendix E of the report.

With respect to previous OSW policy and guidelines on levels, Techniques and Methods Report Book 3, Chapter A19:

This new report supersedes U.S. Geological Survey (USGS) Techniques of Water-Resources Investigations Book 3, Chapter A19, 1990, “Levels at Streamflow Gaging Stations,” by E.J. Kennedy and USGS Open-File Report 81-1104, 1981 “Manual for leveling at gaging stations in North Carolina” by N.O. Thomas and N.M. Jackson, Jr.

Copies of the report have been mailed to each of the main Water Science Center offices. If you need additional copies of the report, please contact the Office of Surface Water.

Suggested citation: Kenney, T.A., 2010, Levels at gaging stations: U.S. Geological Survey Techniques and Methods 3-A19, 60 p. (Also available at
Comments or suggestions about the subject report should be addressed to the Office of Surface Water.

Stephen F. Blanchard /signed/
Chief, Office of Surface Water

U.S. Geological Survey
National Center, MS 415
12201 Sunrise Valley Drive
Reston, VA 20192


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