Discharge Measurements at Gaging Stations

Techniques and Methods 3-A8
By:  and 



The techniques and standards for making discharge measurements at streamflow gaging stations are described in this publication. The vertical axis rotating-element current meter, principally the Price current meter, has been traditionally used for most measurements of discharge; however, advancements in acoustic technology have led to important developments in the use of acoustic Doppler current profilers, acoustic Doppler velocimeters, and other emerging technologies for the measurement of discharge. These new instruments, based on acoustic Doppler theory, have the advantage of no moving parts, and in the case of the acoustic Doppler current profiler, quickly and easily provide three-dimensional stream-velocity profile data through much of the vertical water column. For much of the discussion of acoustic Doppler current profiler moving-boat methodology, the reader is referred to U.S. Geological Survey Techniques and Methods 3–A22 (Mueller and Wagner, 2009).

Personal digital assistants (PDAs), electronic field notebooks, and other personal computers provide fast and efficient data-collection methods that are more error-free than traditional hand methods. The use of portable weirs and flumes, floats, volumetric tanks, indirect methods, and tracers in measuring discharge are briefly described.

Suggested Citation

Turnipseed, D.P., and Sauer, V.B., 2010, Discharge measurements at gaging stations: U.S. Geological Survey Techniques and Methods book 3, chap. A8, 87 p. (Also available at https://pubs.usgs.gov/tm/tm3-a8/.)

ISSN: 2328-7055 (online)

Table of Contents

  • Preface
  • Abstract
  • Purpose and Scope
  • Definition of Streamflow
  • Discharge Measurements at Gaging Stations
  • Measurement of Width
  • Measurement of Depth
  • Measurement of Velocity
  • Direction of Flow Measurements
  • Current-Meter Measurements by Wading
  • Current-Meter Measurements From Cableways
  • Current-Meter Measurements From Bridges
  • Current-Meter Measurements From Ice Cover
  • Current-Meter Measurements From Stationary Boats
  • Moving-Boat Measurements of Discharge
  • Networks of Current Meters
  • Discharge Measurement of Deep, Swift Streams With a Mechanical Current Meter
  • Recording Field Notes
  • Mean Gage Height of Discharge Measurements
  • Discharge Measurements During Rapidly Changing Stage
  • Correction of Discharge for Storage During Measurement
  • Instruments and Equipment
  • Accuracy of Current-Meter Discharge Measurements
  • Quality Assurance and Quality Control
  • Safety Requirements
  • Portable Weir-Plate Measurements
  • Portable Parshall-Flume Measurements
  • Float Measurements
  • Indirect Discharge Measurements
  • Tracer Discharge Measurements
  • References Cited
Publication type Report
Publication Subtype USGS Numbered Series
Title Discharge measurements at gaging stations
Series title Techniques and Methods
Series number 3-A8
DOI 10.3133/tm3A8
Year Published 2010
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) U.S. Geological Survey
Description xiv, 87 p.
Public Comments This edition supersedes USGS Techniques of Water-Resources Investigations 3A–8, 1969, “Discharge measurements at gaging stations,” by T.J. Buchanan and W.P. Somers, available at https://pubs.usgs.gov/twri/twri3a8/, and supplements USGS Water-Supply Paper 2175, volume 1, 1982, “Measurement and computation of streamflow: Measurement of stage and discharge,” by S.E. Rantz and others, available at https://pubs.usgs.gov/wsp/wsp2175/.
Online Only (Y/N) Y
Additional Online Files (Y/N) N
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