ASTM D5737/D5737M-19

Standard Guide for Methods for Measuring Well Discharge

SIGNIFICANCE AND USE
4.1 This guide is limited to the description of test methods typical for measurement of ground water discharge from a control well.  
4.1.1 Controlled field tests are the primary means of determining aquifer properties. Most mathematical equations developed for analyzing field tests require measurement of control well discharge.  
4.1.2 Discharge may be needed for evaluation of well design and efficiency.  
4.1.3 For aquifer tests, a conceptual model should be prepared to evaluate the proper test method and physical test requirements, such as well placement and design (see Guide D4043). Review the site data for consistency with the conceptual model. Revise the conceptual model as appropriate and consider the implications on the planned activities.  
4.1.4 For aquifer tests, the discharge rate should be sufficient to cause significant stress of the aquifer without violating test assumptions. Conditions that may violate test assumptions include conversion of the aquifer from confined to unconfined conditions, lowering the water level in the control well to below the top of the well screen, causing a well screen entrance velocity that promotes well development during the test, or decreasing the filter pack permeability characteristics.  
4.1.5 Some test methods described here are not applicable to injection well tests.  
4.2 This guide does not apply to test methods used in measurement of flow of other fluids used in industrial operations, such as waste water, sludge, oil, and chemicals.
Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors;...
SCOPE
1.1 This guide covers an overview of methods to measure well discharge. This guide is an integral part of a series of standards prepared on the in-situ determination of hydraulic properties of aquifer systems by single- or multiple-well tests. Measurement of well discharge is a common requirement to the determination of aquifer and well hydraulic properties.  
1.2 This guide does not establish a fixed procedure for any method described. Rather, it describes different methods for measuring discharge from a pumping or flowing well. A pumping well is one type of control well. A control well can also be an injection well or a well in which slug tests are conducted.  
1.3 This guide does not address borehole flow meters that are designed for measuring vertical or horizontal flow within a borehole.  
1.4 Units—The values stated in either SI units or inch-pound units [presented in brackets] are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. Reporting of results in units other than SI shall not be regarded as nonconformance with this standard.  
1.5 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus ...

General Information

• Status: Published
• Publication Date: 31-Oct-2019
• ICS: 17.120.20 - Flow in open channels
• Technical Committee: D18 - Soil and Rock
• Drafting Committee: D18.21 - Groundwater and Vadose Zone Investigations

Relations

• Replaces: ASTM D5737/D5737M-14 - Standard Guide for Methods for Measuring Well Discharge
• Effective Date: 01-Nov-2019
• Refers: ASTM D3740-23 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Nov-2023
• Refers: ASTM D3740-19 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Oct-2019
• Refers: ASTM D4043-17 - Standard Guide for Selection of Aquifer Test Method in Determining Hydraulic Properties by Well Techniques
• Effective Date: 01-Jan-2017
• Refers: ASTM D653-14 - Standard Terminology Relating to Soil, Rock, and Contained Fluids
• Effective Date: 01-Aug-2014
• Refers: ASTM D3740-12a - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-May-2012
• Refers: ASTM D3740-12 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Mar-2012
• Refers: ASTM D653-11 - Standard Terminology Relating to Soil, Rock, and Contained Fluids
• Effective Date: 01-Sep-2011
• Refers: ASTM D3740-11 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Sep-2011
• Refers: ASTM D4043-96(2010)e1 - Standard Guide for Selection of Aquifer Test Method in Determining Hydraulic Properties by Well Techniques
• Effective Date: 01-Aug-2010
• Refers: ASTM D3740-10 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Mar-2010
• Refers: ASTM D653-09 - Standard Terminology Relating to Soil, Rock, and Contained Fluids
• Effective Date: 01-Jan-2009
• Refers: ASTM D653-08a - Standard Terminology Relating to Soil, Rock, and Contained Fluids
• Effective Date: 01-Dec-2008
• Refers: ASTM D653-08 - Standard Terminology Relating to Soil, Rock, and Contained Fluids
• Effective Date: 01-Nov-2008
• Refers: ASTM D3740-08 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Mar-2008

Overview

ASTM D5737/D5737M-19 is the Standard Guide for Methods for Measuring Well Discharge, published by ASTM International. This standard provides guidance on various methods to measure groundwater discharge from control wells, which is essential for accurate aquifer testing and the evaluation of well design and efficiency. Precise measurement of well discharge rates is a critical requirement in determining both aquifer and well hydraulic properties. The guide forms part of a series addressing in-situ determinations in hydrogeologic investigations and is applicable primarily to groundwater flow and aquifer testing.

Key Topics

• Methods of Measuring Well Discharge: The guide covers a range of techniques suitable for pumping or flowing wells, emphasizing both open channel and closed conduit flow measurement methods.

  • Open Channel Flow Methods
    • Weirs (sharp crested): Inexpensive, reliable, and suitable for accurate low-flow measurements.
    • Flumes (Parshall flume): Handle a wide range of flows with minimal head loss and self-cleaning capability.
  • Closed Conduit Flow Methods
    • Turbine (Propeller) Flow Meters: Typically totalize flow volume in-line and require proper calibration.
    • Magnetic Flow Meters: Offer no head loss and facilitate continuous readings but can be costlier.
    • Venturi Meters: Lower maintenance and head loss with reliable performance.
    • Acoustic (Doppler) Meters: Use sound waves for flow estimation, ideal for applications with suspended material.
  • Discharge to Air Methods
    • Bucket and Stop Watch: Manual, straightforward, and best for intermittent, low-precision tasks.
    • Orifice Buckets and Weirs: Suitable for variable discharge rates, with calibrated readings for enhanced accuracy.
    • Trajectory Method: Determines flow rate based on the water trajectory from horizontal or vertical pipes.

• Significance in Aquifer Testing:

  • Accurate discharge measurement is integral to determining aquifer properties via controlled field tests and mathematical solutions.
  • Selection of methods depends on required accuracy, flow rate, and site-specific circumstances.
  • The guide stresses the importance of preparing a conceptual site model and the need for professional judgment in applying these methods.

• Limitations:

  • The guide does not specify fixed procedures for individual methods, nor does it address borehole flow meters for intra-borehole flow.
  • Not all methods are suitable for injection wells or non-water fluids such as wastewater or chemicals.

• Reporting and Documentation:

  • A report should detail the purpose of the discharge measurement, selected methods, measurement frequency, and accuracy goals.
  • Personnel responsible for measurements must be identified.

Applications

• Hydrogeologic Investigations: Used in groundwater studies to determine aquifer hydraulic properties through pumping or slug tests.
• Well Design and Efficiency Evaluation: Helps assess whether existing or proposed well designs are performing as expected.
• Aquifer Stress Testing: Ensures discharge rates induce sufficient aquifer response for accurate data without violating test assumptions.
• Environmental and Regulatory Compliance: Supports requirements for precise discharge documentation in water resource management and site contaminated land assessments.

Related Standards

• ASTM D4043 - Guide for Selection of Aquifer Test Method in Determining Hydraulic Properties by Well Techniques
• ASTM D653 - Terminology Relating to Soil, Rock, and Contained Fluids
• ASTM D1941, D5242, D5390, D5716 - Various methods for open-channel and orifice-based flow measurements
• ASTM D3740 - Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock
• ASTM D6026 - Practice for Using Significant Digits in Geotechnical Data
• ISO Recommendation R541 - Measurement of Fluid Flow by Means of Orifice Plates and Nozzles
• ANSI Standard 1042 Part 1 - Methods for the Measurement of Fluid Flow in Pipes
• ASME MFC-3M-1995 - Measurement of Fluid Flow in Pipes Using Orifice, Nozzle, and Venturi

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Keywords: well discharge, groundwater measurement, aquifer testing, flow rate measurement, weir, flume, discharge methods, ASTM D5737/D5737M-19, hydrogeologic testing, water resource management

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D5737/D5737M − 19
Standard Guide for
Methods for Measuring Well Discharge
This standard is issued under the fixed designation D5737/D5737M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* 1.6 All observed and calculated values shall conform to the
guidelines for significant digits and rounding established in
1.1 This guide covers an overview of methods to measure
Practice D6026.
well discharge. This guide is an integral part of a series of
1.6.1 Theproceduresusedtospecifyhowdataarecollected/
standards prepared on the in-situ determination of hydraulic
recorded or calculated in the standard are regarded as the
properties of aquifer systems by single- or multiple-well tests.
industry standard. In addition, they are representative of the
Measurement of well discharge is a common requirement to
significant digits that generally should be retained. The proce-
the determination of aquifer and well hydraulic properties.
dures used do not consider material variation, purpose for
1.2 This guide does not establish a fixed procedure for any
obtaining the data, special purpose studies, or any consider-
method described. Rather, it describes different methods for
ations for the user’s objectives; and it is common practice to
measuring discharge from a pumping or flowing well. A
increase or reduce significant digits of reported data to be
pumping well is one type of control well. A control well can
commensuratewiththeseconsiderations.Itisbeyondthescope
also be an injection well or a well in which slug tests are
of this standard to consider significant digits used in analysis
conducted.
methods for engineering data.
1.3 This guide does not address borehole flow meters that
1.7 This standard does not purport to address all of the
are designed for measuring vertical or horizontal flow within a
safety concerns, if any, associated with its use. It is the
borehole.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
1.4 Units—The values stated in either SI units or inch-
mine the applicability of regulatory limitations prior to use.
pound units [presented in brackets] are to be regarded sepa-
Furthermore, it is the user’s responsibility to properly dispose
rately as standard.The values stated in each system may not be
of water discharged.
exact equivalents; therefore, each system shall be used inde-
1.8 This international standard was developed in accor-
pendentlyoftheother.Combiningvaluesfromthetwosystems
dance with internationally recognized principles on standard-
may result in non-conformance with the standard. Reporting of
ization established in the Decision on Principles for the
results in units other than SI shall not be regarded as noncon-
Development of International Standards, Guides and Recom-
formance with this standard.
mendations issued by the World Trade Organization Technical
1.5 This guide offers an organized collection of information
Barriers to Trade (TBT) Committee.
or a series of options and does not recommend a specific
course of action. This document cannot replace education or
2. Referenced Documents
experience and should be used in conjunction with professional
2.1 ASTM Standards:
judgment. Not all aspects of this guide may be applicable in all
D653 Terminology Relating to Soil, Rock, and Contained
circumstances. This ASTM standard is not intended to repre-
Fluids
sent or replace the standard of care by which the adequacy of
D1941 Test Method for Open Channel Flow Measurement
a given professional service must be judged, nor should this
of Water with the Parshall Flume
document be applied without consideration of a project’s many
D3740 Practice for Minimum Requirements for Agencies
unique aspects. The word “Standard” in the title of this
Engaged in Testing and/or Inspection of Soil and Rock as
document means only that the document has been approved
Used in Engineering Design and Construction
through the ASTM consensus process.
D4043 Guide for Selection of Aquifer Test Method in
Determining Hydraulic Properties by Well Techniques
This guide is under the jurisdiction ofASTM Committee D18 on Soil and Rock
and is the direct responsibility of Subcommittee D18.21 on Groundwater and
Vadose Zone Investigations. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Nov. 1, 2019. Published December 2019. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1995. Last previous edition approved in 2014 as D5737 – 14. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/D5737_D5737M-19. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5737/D5737M − 19
dependent on the competence of the personnel performing it, and the
D5242 Test Method for Open-Channel Flow Measurement
suitability of the equipment and facilities used. Agencies that meet the
of Water with Thin-Plate Weirs
criteria of Practice D3740 are generally considered capable of competent
D5390 Test Method for Open-Channel Flow Measurement
and objective testing/sampling/inspection/etc. Users of this standard are
of Water with Palmer-Bowlus Flumes
cautioned that compliance with Practice D3740 does not in itself assure
D5716 Test Method for Measuring the Rate of Well Dis-
reliable results. Reliable results depend on many factors; Practice D3740
provides a means of evaluating some of those factors.
charge by Circular Orifice Weir
D6026 Practice for Using Significant Digits in Geotechnical
5. Measurement Methods
Data
5.1 Selection of a Well Discharge Rate Measurement
2.2 ISO Standard:
Method—Select a well discharge measurement method based
Recommendation R541 Measurement of Fluid Flow by
on the desired discharge rate or rates, the desired pumping
Means of Orifice Plates and Nozzles
method, the needed accuracy and frequency of measurement,
2.3 ANSI Standard:
the type of pump discharge and the water conveyance method.
Standard 1042 Part1MethodsfortheMeasurementofFluid
Flow in Pipes, 1, Orifice Plates, Nozzles and Venturi
5.2 Principal Well Discharge Rate Measurement
Tubes
Methods—Asummary of principal methods is given below for
2.4 ASME Standard:
typical hydrogeologic testing. Additional information may be
Standard MFC-3M-1995 Measurement of Fluid Flow in
found in a publication of the National Institute of Standards
Pipes Using Orifice, Nozzle, and Venturi
and Technology (NIST) (1), the American Society of Me-
chanical Engineers (ASME) (2), or in a comprehensive book
3. Terminology
on the subject of flow meter engineering (3). Discharge
3.1 Definitions—For definitions of common technical terms
methods can be classified as open channel flow and closed
used within this standard, refer to Terminology D653.
conduit flow. Open channel flow is limited to calibrated control
structures, such as weirs and flumes. Closed conduit flow
4. Significance and Use
includes methods such as turbine meters and magnetic meters.
4.1 This guide is limited to the description of test methods
Also included are methods that measure the discharge of water
typical for measurement of ground water discharge from a
from the closed conduit to the air, such as the orifice tube.
control well.
5.3 Open Channel Flow Methods:
4.1.1 Controlled field tests are the primary means of deter-
5.3.1 Weirs—A weir is a vertical obstruction that restricts
mining aquifer properties. Most mathematical equations devel-
the total flow of water in channel. Weirs fall into three general
oped for analyzing field tests require measurement of control
classifications, sharp crested, broad crested, and suppressed.
well discharge.
Sharp crested weirs use a flat plate that is configured in a
4.1.2 Discharge may be needed for evaluation of well
triangular “V” or rectangular shape; they are described in
design and efficiency.
5.3.1.1. See Test Method D5242. Broad crested weirs are wide
4.1.3 For aquifer tests, a conceptual model should be
rectangular restrictions that are usually only used as spillways
prepared to evaluate the proper test method and physical test
in dams. They are not described here. More information on
requirements, such as well placement and design (see Guide
broad crested weirs may be found in Ref (4). A third classifi-
D4043). Review the site data for consistency with the concep-
cation of weirs, called suppressed weirs, are more commonly
tual model. Revise the conceptual model as appropriate and
known as flumes. Flumes are discussed in 5.3.2.
consider the implications on the planned activities.
5.3.1.1 Sharp Crested Weirs—The weir is placed flush
4.1.4 For aquifer tests, the discharge rate should be suffi-
against the flowing stream, and the notch is made as sharp as
cient to cause significant stress of the aquifer without violating
practicableusingaflatpieceofmetalwithsharpedgesforming
test assumptions. Conditions that may violate test assumptions
theweirnotch.Therelationbetweentheheadandthedischarge
include conversion of the aquifer from confined to unconfined
of a weir varies according to the shape of the weir notch. A
conditions, lowering the water level in the control well to
weir is inexpensive to construct, easy to install and highly
belowthetopofthewellscreen,causingawellscreenentrance
accurate when installed and used correctly.
velocity that promotes well development during the test, or
5.3.2 Flume—A flume is a device that restricts flow in the
decreasing the filter pack permeability characteristics.
channel which causes the water to accelerate, producing a
4.1.5 Sometestmethodsdescribedherearenotapplicableto
corresponding change in the water level. The head can then be
injection well tests.
related to discharge. Several types of flumes have been
4.2 This guide does not apply to test methods used in
developed; the most common flume for measuring well dis-
measurement o
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5737/D5737M − 14 D5737/D5737M − 19
Standard Guide for
Methods for Measuring Well Discharge
This standard is issued under the fixed designation D5737/D5737M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This guide covers an overview of methods to measure well discharge. This guide is an integral part of a series of standards
prepared on the in-situ determination of hydraulic properties of aquifer systems by single- or multiple-well tests. Measurement of
well discharge is a common requirement to the determination of aquifer and well hydraulic properties.
1.2 This guide does not establish a fixed procedure for any method described. Rather, it describes different methods for
measuring discharge from a pumping or flowing well. A pumping well is one type of control well. A control well can also be an
injection well or a well in which slug tests are conducted.
1.3 This guide does not address borehole flow meters that are designed for measuring vertical or horizontal flow within a
borehole.
1.4 Units—The values stated in either SI units or inch-pound units [presented in brackets] are to be regarded separately as
standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of
the other. Combining values from the two systems may result in non-conformance with the standard. Reporting of results in units
other than SI shall not be regarded as nonconformance with this standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use. Furthermore, it is the user’s responsibility to properly dispose of water discharged.
1.5 This guide offers an organized collection of information or a series of options and does not recommend a specific course
of action. This document cannot replace education or experience and should be used in conjunction with professional judgment.
Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replace
the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied
without consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the
document has been approved through the ASTM consensus process.
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice
D6026.
1.6.1 The procedures used to specify how data are collected/recorded or calculated in the standard are regarded as the industry
standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not
consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives;
and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations.
It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering data.
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use. Furthermore, it is the user’s responsibility to properly dispose of water discharged.
1.8 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
This guide is under the jurisdiction of ASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.21 on Groundwater and Vadose
Zone Investigations.
Current edition approved June 1, 2014Nov. 1, 2019. Published July 2014December 2019. Originally approved in 1995. Last previous edition approved in 20062014 as
D5737 – 95 (2006).D5737 – 14. DOI: 10.1520/D5737_D5737M-14.10.1520/D5737_D5737M-19.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5737/D5737M − 19
2. Referenced Documents
2.1 ASTM Standards:
D653 Terminology Relating to Soil, Rock, and Contained Fluids
D1941 Test Method for Open Channel Flow Measurement of Water with the Parshall Flume
D3740 Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in
Engineering Design and Construction
D4043 Guide for Selection of Aquifer Test Method in Determining Hydraulic Properties by Well Techniques
D5242 Test Method for Open-Channel Flow Measurement of Water with Thin-Plate Weirs
D5390 Test Method for Open-Channel Flow Measurement of Water with Palmer-Bowlus Flumes
D5716 Test Method for Measuring the Rate of Well Discharge by Circular Orifice Weir
D6026 Practice for Using Significant Digits in Geotechnical Data
2.2 ISO Standard:
Recommendation R541 Measurement of Fluid Flow by Means of Orifice Plates and Nozzles
2.3 ANSI Standard:
Standard 1042 Part 1 Methods for the Measurement of Fluid Flow in Pipes, 1, Orifice Plates, Nozzles and Venturi Tubes
2.4 ASME Standard:
Standard MFC-3M-1995 Measurement of Fluid Flow in Pipes Using Orifice, Nozzle, and Venturi
3. Terminology
3.1 Definitions—For definitions of common technical terms used within this guidestandard, refer to Terminology D653.
4. Significance and Use
4.1 This guide is limited to the description of test methods typical for measurement of ground water discharge from a control
well.
4.1.1 Controlled field tests are the primary means of determining aquifer properties. Most mathematical equations developed
for analyzing field tests require measurement of control well discharge.
4.1.2 Discharge may be needed for evaluation of well design and efficiency.
4.1.3 For aquifer tests, a conceptual model should be prepared to evaluate the proper test method and physical test requirements,
such as well placement and design (see Guide D4043). Review the site data for consistency with the conceptual model. Revise the
conceptual model as appropriate and consider the implications on the planned activities.
4.1.4 For aquifer tests, the discharge rate should be sufficient to cause significant stress of the aquifer without violating test
assumptions. Conditions that may violate test assumptions include conversion of the aquifer from confined to unconfined
conditions, lowering the water level in the control well to below the top of the well screen, causing a well screen entrance velocity
that promotes well development during the test, or decreasing the filter pack permeability characteristics.
4.1.5 Some test methods described here are not applicable to injection well tests.
4.2 This guide does not apply to test methods used in measurement of flow of other fluids used in industrial operations, such
as waste water, sludge, oil, and chemicals.
NOTE 1—The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the
equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective
testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable
results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.
5. TestMeasurement Methods
5.1 Selection of a Well Discharge Rate Measurement Method—Select a well discharge measurement method based on the
desired discharge rate or rates, the desired pumping method, the requiredneeded accuracy and frequency of measurement, the type
of pump discharge and the water conveyance method.
5.2 Principal Well Discharge Rate Measurement Methods—A summary of principal methods is given below for typical
hydrogeologic testing. Additional information may be found in a publication of the National Institute of Standards and Technology
(NIST) (1), the American Society of Mechanical Engineers (ASME) (2), or in a comprehensive book on the subject of flow meter
engineering (3). Discharge methods can be classified as open channel flow and closed conduit flow. Open channel flow is limited
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
Available from American Society of Mechanical Engineers (ASME), ASME International Headquarters, Two Park Ave., New York, NY 10016-5990, http://
www.asme.org.
The boldface numbers given in parentheses refer to a list of references at the end of the text.
D5737/D5737M − 19
to calibrated control structures, such as weirs and flumes. Closed conduit flow includes methods such as turbine meters and
magnetic meters. Also included are methods that measure the discharge of water from the closed conduit to the air, such as the
orifice tube.
5.3 Open Channel Flow Methods:
5.3.1 Weirs—A weir is a vertical obstruction that restricts the total flow of water in channel. Weirs fall into three general
classifications, sharp crested, broad crested, and suppressed. Sharp crested weirs use a flat plate that is configured in a triangular
“V” or rectangular shape; they are described in 5.3.1.1. See Test Method D5242. Broad crested weirs are wide rectangular
restrictions that are usually only used as spillways in dams. They are not described here. More information on broad crested weirs
may be found in Ref (4). A third classification of weirs, called suppressed weirs, are more commonly known as flumes. Flumes
are discussed in 5.3.2.
5.3.1.1 Sharp Crested Weirs—The weir is placed flush against the flowing stream, and the notch is made as sharp as
possiblepracticable using a flat piece of metal with sharp edges forming the we
...