Which are the methods used for discharge measurement?

Stream discharge can be measured using (1) volumetric gauging, (2) float gauging, (3) current metering, (4) dilution gauging (constant injection or gulp methods), (5) structural methods, and (6) slope-area methods. The choice of method depends on the characteristics of the stream and on the application.

What is a USGS gauge?

Most USGS streamgages are used to generate continuous streamflow information year-round. Together these gages constitute the National Streamflow Network. Some gages, however, only record the water level (gage height or stage) of a stream, lake or reservoir; no streamflow (discharge) is computed.

How does a USGS Streamgage work?

USGS computers use these site-specific rating curves to convert the water-level data into information about the flow of the river. The rating curve is developed from a number of physical discharge measurements collected over a period of time and over a range of stages (from low flow to flood stage).

Which is the simplest method to measure the discharge rate of a well?

A simple method is to see how fast a floating object travels downstream over a chosen distance. This is called the float method.

What is float method?

Float method – This method measures surface velocity. Mean velocity is obtained using a correction factor. The basic idea is to measure the time that it takes the object to float a specified distance downstream.

What is discharge USGS?

discharge = area x velocity The USGS uses numerous methods and types of equipment to measure velocity and cross-sectional area, including the following current meter and Acoustic Doppler Current Profiler. Sources/Usage: Public Domain.

What does USGS stand for?

The U.S. Geological Survey
The U.S. Geological Survey is the nation’s largest water, earth, and biological science and civilian mapping agency. It collects, monitors, analyzes, and provides scientific understanding of natural resource conditions, issues, and problems.

Why does the USGS use the spelling Gage instead of gauge?

Newell is purported to be the person responsible for the adoption of the USGS spelling of “gage” instead of “gauge”. Around 1892, Newell reasoned that “gage” was the proper Saxon spelling before the Norman influence added a ‘u’.

How do you calculate stream flow?

Multiply the average depth of the stream by the width of the stream to find the area in ft2. Divide the distance traveled by the average travel time to find the velocity of the stream in ft/sec. Multiply the velocity of the stream by a correction factor. This is the corrected velocity of the stream.

How will you measure discharge using current meter?

In the simplest method, a current meter turns with the flow of the river or stream. The current meter is used to measure water velocity at predetermined points (subsections) along a marked line, suspended cableway, or bridge across a river or stream. The depth of the water is also measured at each point.

What is tracer dilution method?

Tracer dilution is a method of determining the flow rate in a ground or surface water environment where a hydraulic structure (flume / weir) cannot be installed either due to cost, monitoring duration, or ecological reasons.

What is gage height USGS?

Stream stage (also called stage or gage height) is the height of the water surface, in feet, above an established altitude where the stage is zero. The zero level is arbitrary, but is often close to the streambed.

What are three major streamflow measurements?

Number of Velocity Measurements per Vertical There are three methods: One-point, Two-point, and Three-point.

What is USGS data used for?

The U.S. Geological Survey is the nation’s largest water, earth, and biological science and civilian mapping agency. It collects, monitors, analyzes, and provides scientific understanding of natural resource conditions, issues, and problems.

Why is USGS important?

The USGS provides science about the natural hazards that threaten lives and livelihoods; the water, energy, minerals, and other natural resources we rely on; the health of our ecosystems and environment; and the impacts of climate and land-use change.

What do USGS gauging stations directly measure?

A streamgage contains instruments that measure and record the amount of water flowing in the river or stream, or its discharge. Generally, these measurements occur automatically every 15 minutes or more frequently in times of flooding.

What are indirect method to compute discharge?

The slope-area method is the most commonly used technique of indirect discharge determination. In the slope-area method, discharge is computed on the basis of a uniform-flow equation involving channel characteristics, water-surface profiles, and a roughness or retardation coefficient.

How are stream discharge data collected?

Stream stage (or water level) and streamflow (or discharge) are measured at locations called streamflow gaging stations. Stage is measured and recorded continuously by electronic instruments.

What is the best method for measuring discharge?

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.

How is discharge measured at gage stations?

The use of portable weirs and flumes, floats, volumetric tanks, indirect methods, and tracers in measuring discharge are briefly described. 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.

How do you calculate the discharge from a channel?

Pacific Creek at Moran, WY x Water Velocity Cross section area Discharge = (Area of water in cross section) x (Water velocity) THE VELOCITY-AREA METHOD Discharge of each sub-section = Area x Average Water Velocity The channel cross section is divided into numerous sub-sections Total Discharge = ((Area 1x Velocity 1 ) + (Area 2x Velocity

How do you calculate discharge from a cross sectional area?

x Water Velocity Cross section area Discharge = (Area of water in cross section) x (Water velocity) THE VELOCITY-AREA METHOD Discharge of each sub-section = Area x Average Water Velocity