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National Field Manual for the Collection of Water-Quality Data (NFM) Active

By Water Resources Mission Area February 28, 2019

New NFM publication: Chapter A6.4 pH

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The National Field Manual for the Collection of Water-Quality Data (NFM) provides documented methods and protocols for USGS field personnel who collect water-quality data. The NFM provides detailed, comprehensive, and citable procedures for sampling water resources, processing samples for analysis of water quality, measuring field parameters, and specialized procedures.

USGS WQ field Manual Logo
Sources/Usage: Public Domain.

As part of its mission, the USGS collects data to assess the quality of our Nation’s water resources. A high degree of reliability and standardization of these data are paramount to fulfilling this mission. Documentation of nationally accepted methods used by USGS personnel serves to maintain consistency and technical quality in data-collection activities. The National Field Manual for the Collection of Water-Quality Data (NFM) provides documented guidelines and protocols for USGS field personnel who collect water-quality data. The NFM provides detailed, comprehensive, and citable procedures for monitoring the quality of surface water and groundwater. Topics in the NFM include:

  1. Methods and protocols for sampling water resources
  2. Methods for processing samples for analysis of water quality
  3. Methods for measuring field parameters
  4. Specialized procedures, such as sampling water for low levels of mercury and organic wastewater chemicals, measuring biological indicators, and sampling bottom sediment for chemistry.

Personnel who collect water-quality data for national USGS programs and projects, including projects supported by USGS cooperative programs, are mandated to use protocols provided in the NFM per USGS Office of Water Quality Technical Memorandum 2002.13. Formal training, for example, as provided in the USGS class, “Field Water-Quality Methods for Groundwater and Surface Water,” and field apprenticeships supplement the guidance provided in the NFM and ensure that the data collected are high quality, accurate, and scientifically defensible.

File icon USGS Technical and Policy Memorandums that relate to the NFM

Before 2017, NFM chapters were released in the USGS Techniques of Water-Resources Investigations (TWRI) series. Effective in 2017, new and revised NFM chapters are being released in the USGS Techniques and Methods series, which was established in 2003 to replace the TWRI series and other USGS reports. The change in the series classification does not in itself affect the content and format of the NFM. Each chapter of the NFM is reviewed regularly and revised periodically to update procedures, incorporate technical advances, and to address additional emerging topics of relevance to water quality field studies.

 

USGS National Field Manual for the Collection of Water-Quality Data:
Table of Contents

A0. General Introduction for the NFM (Version 1.1, 6/2018)

A1. Preparations for Water Sampling (11/2018).

A2. Selection of Equipment for Water Sampling (Version 3.1, 4/2014)

A3. Cleaning of Equipment for Water Sampling (Version 2.0, 4/2004)

A4. Collection of Water Samples (Version 2.0, 9/2006)

A5. Processing of Water Samples, Version 2.2 (9/2004)

A6. Field Measurements

A7. Biological Indicators

A8. Bottom-Material Samples (Version 1.1, 6/2005)

A9. Superceded by the USGS handbook on "Safety and Health for Field Operations" (USGS 2014)

A10. Lakes and Reservoirs: Guidelines for Study Design and Sampling

 

Comments and errata for the NFM can be found here.

Below are publications associated with the National Field Manual for the Collection of Water-Quality Data (NFM).

Water-quality sampling by the U.S. Geological Survey-Standard protocols and procedures

Thumbnail of and link to report PDF (1.0 MB) The U.S. Geological Survey (USGS) develops the sampling procedures and collects the data necessary for the accurate assessment and wise management of our Nation's surface-water and groundwater resources. Federal and State agencies, water-resource regulators and managers, and many organizations and interested parties in the public and private sectors
Filter Total Items: 26

Chapter A6. Section 6.4. pH

Measurement of pH is critical to the understanding of the viability and vulnerability of environmental waters and is considered a master variable in determining the aqueous geochemistry of an aqueous system. pH is a measure that represents the hydrogen-ion concentration (activity) of a solution. This section of the National Field Manual (NFM) describes U.S. Geological Survey (USGS) guidance and pr

Chapter A6.2. Dissolved oxygen

The “National Field Manual for the Collection of Water-Quality Data” (NFM) provides guidelines and procedures for U.S. Geological Survey (USGS) personnel who collect data used to assess the quality of the Nation’s surface water and groundwater resources. This chapter, NFM A6.2, provides guidance and protocols for the measurement of dissolved oxygen, which include the scientific basis of the measur
By
Water Resources Mission Area

Preparations for water sampling

The “National Field Manual for the Collection of Water-Quality Data” (NFM) provides guidelines and procedures for U.S. Geological Survey (USGS) personnel who collect data used to assess the quality of the Nation’s surface-water and groundwater resources. This chapter, NFM A1, provides an overview of preparations for water sampling, which includes site reconnaissance, project work plans, quality-as

General introduction for the “National Field Manual for the Collection of Water-Quality Data”

BackgroundAs part of its mission, the U.S. Geological Survey (USGS) collects data to assess the quality of our Nation’s water resources. A high degree of reliability and standardization of these data are paramount to fulfilling this mission. Documentation of nationally accepted methods used by USGS personnel serves to maintain consistency and technical quality in data-collection activities. “The N
By
National Water Quality Program

Capsule- and disk-filter procedure

Capsule and disk filters are disposable, self-contained units composed of a pleated or woven filter medium encased in a polypropylene or other plastic housing that can be connected inline to a sample-delivery system (such as a submersible or peristaltic pump) that generates sufficient pressure (positive or negative) to force water through the filter. Filter media are available in several pore size

Lakes and reservoirs—Guidelines for study design and sampling

The “National Field Manual for the Collection of Water-Quality Data” (NFM) is an online report with separately published chapters that provides the protocols and guidelines by which U.S. Geological Survey personnel obtain the data used to assess the quality of the Nation’s surface-water and groundwater resources. Chapter A10 reviews limnological principles, describes the characteristics that disti
By
Water Resources Mission Area, Lower Mississippi-Gulf Water Science Center

Chapter A5. Section 2.2B. Syringe-Filter Procedure for Processing Samples for Analysis of Organic Compounds by DAI LC-MS/MS

This section of chapter 5 of the National Field Manual for the Collection of Water-Quality Data (NFM) describes the field procedures for collecting small-volume samples using a syringe-tip filtration method. The samples are sent to the U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL) for analysis of organic compounds by direct aqueous injection high-performance liquid chromat
By
Water Resources Mission Area, National Water Quality Laboratory

Chapter A7. Section 7.2. Fecal Indicator Viruses

More than 100 types of human pathogenic viruses may be present in fecal-contaminated waters. Coliphages are used as indicators of virus-related fecal contamination and of the microbiological quality of waters. This report provides information on the equipment, sampling protocols, and laboratory methods that are in standard use by U.S. Geological Survey (USGS) personnel for the collection of data o

Chapter A5. Section 6.4.A. Arsenic Speciation

Two sample-processing methods (field speciation and laboratory speciation) used at the USGS National Water Quality Laboratory (NWQL) are specific to sample analysis by inductively coupled plasma-mass spectrometry (ICP-MS) for determining the concentration of inorganic and organic arsenic species in a water sample. The field-speciation method requires NWQL Schedule 1729. The laboratory-speciation m

Chapter A6. Section 6.0. General information and guidelines for field-measured water-quality properties

This report summarizes information, guidelines, and minimum requirements that apply generally to the seven field-measurement sections that comprise the rest of Chapter A6 of this U.S. Geological Survey (USGS) National Field Manual for the Collection of Water-Quality Data (NFM). Protocols are specified for establishing and maintaining data records, use of field-measurement instruments and methods,

Chapter A7. Section 7.3. Protozoan Pathogens

Protozoan pathogens are widely distributed in the aquatic environment. Cryptosporidium and Giardia are the principal protozoan pathogens that are known to affect the acceptability of water supplies for public use within the United States. A sampling program for protozoan pathogens should be conducted over an extended period of time because of cyclical and seasonal variations in their concentration

Chapter A6. Section 6.5. Reduction-Oxidation Potential (Electrode Method)

Reduction-oxidation (redox) potential--also referred to as Eh--is a measure of the equilibrium potential, relative to the standard hydrogen electrode, developed at the interface between a noble metal electrode and an aqueous solution containing electroactive chemical species. Measurements of Eh are used to evaluate geochemical speciation models, and Eh data can provide insights on the evolution an