FLOOD06950

• County: Statewide
• Basin: Statewide
• Title: Techniques of Water-Resources Investigations of the US Geological Survey General Procedure for Gaging Streams
• Date: 1/1/1968
• Prepared By: USGS
• Floodplain - Doc Type: Educational/Technical/Reference Information

GENERAL PROCEDURE FOR GAGING STREAMS

By R. W. Carter and Jacob Davidian

Abstract

This chapter brielly describes the objectives and pro-
cedures used in obtaining streamflow records. It is
consideri:'d an introduction to other chapters on sur-
face-water techniques which treat individual prore-
dures in greater detail.

Introduction

Measurement of the flow of streams was be-
guu by the U.S. Geological Sur\'ey in 1888 as
part of special studies relating to the irrigation
of public lands. Since that time svstematic
records of streamflow have been obtained at
more than 16,lXlO places in the United States by
the Geological Survey. In 1967 the stream-
g-aging- network comprised about 9,000 continu-
oils-record stations. In addition. there were
about 7,200 p.trtial-record stations where data
on only ftoodftow or low flow were obtained.
Stream p;aging is the largest operation among
the ""rious hydrolog-ic networks. Streamflow is
the only part of thc hydrologic cycle in which
moisture i~ so confined as to permit re.tlsonu-
hly a{,L'Ul'ate measnrements of the volumes in-
volved. c\ll other measurements in the hydro-
logic cycle are at best only inadequate sa;llples
of the whole.
'Vater in streams serves mall in many ways;
it provides water supply for man and animals,
irrigation wruter for plants, dilution and trans-
port for removal of waste, energy for produc-
tion of power, channels for water transport,
and a medium of recreation. Records of stream-
flow are important in each of these uses.
\"ah'r in streams cnn nlso be a hazard. Floods
('lW1'*-' pxtt~llsin~ dUllIug'e and hardship. Records
of fto(}(l (.y(.]}ts obtailll;'(l at :,!ag-illg' :-:otatioHs Sf'l'Yl;'
as tIlt'- basis fol' tIll' ell'sign of highwllY bl"id~~
and eHln~rts, (lalll~, and f1oO(l~~'ontrol reSl'l"\"Oil'H

l~~

and for flood-plain delineation and flood-
warning systems.
The network of stream-gaging stations is de-
signed to meet the various needs for informa-
tion on streamflow. MallY stations are operlVted
to provide current information for use in the
day-by-day management of water supplies or
for use in forecasting flood events. Most of the
"t"tions, however, are operated as a pam of the
hydrologic network. Records for these stations
reflcct the natural hydrologic characteristics of
the basins and can thus be used as samples of the
variations of streamflow in time and space.
The design of strCltmflow networks is gov-
erned to some extent by the nbilit.y to measure
stage and rliselULrge at a given site to the re-
quired degree of accuracy. The continued de-
velopment of new instrumentation and analyti-
cal techniques has improved the capability of
obhtining streamflow records under difficult
eonditions.
This chapter describes in general terms the
t-edlniqlles used in obtaining- eontilluouS stream-
flow re,'ords-- from selection of site to publica-
tion of records. H is considered an introduction
to four other chapters in book 3, section A,
surfnce-water techniques, which describe in de-
htil the instrumeuts and techniques used in
making specific measurements. This series of
chapters may be considered an updating of
Water-Supply Paper 888, "Stream Gaging
Procedure."

General Objective and Procedures

The objective in operating a gaging station
is to obtain a continuous record of stage and
,liselmrge at the sitc. The exact location of the
station is chosen to take advantage of the best

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