A water quality standard is defined as the designated
beneficial use(s) of a water segment and the water
quality criteria necessary to support those uses (CWA,
1972). Water quality standards establish the environmental baselines used for measuring the health of
aquatic ecosystems.
Measuring water quality
The parameters for water quality are determined by the
intended use. Water quality is measured by several factors, such as the concentration of dissolved oxygen, bacteria levels, nutrients concentrations (commonly nitrogen
and phosphorus), amount of salt (or salinity), or the
amount of material suspended in the water (turbidity).
In some bodies of water, the microscopic algae and quantities of pesticides, herbicides, heavy metals, and other
contaminants may also be measured to determine water
quality. Parameters commonly measured in water bodies
include temperature, pH, turbidity, Secchi disk depth,
dissolved oxygen, conductivity, and oxygen reduction
potential (ORP). Biological metrics have been developed
in many places, and one widely used measure is the presence and abundance of members of the insects. Biological indexes vary from region to region; however, the
greater the number of taxa from these orders, the better
the water quality.
Water quality models
Various water quality models have been used to simulate
the fate of pollutants and the state of selected water quality
variables in water bodies. They incorporate a variety of
physical, chemical, and biological processes that control
the transport and transformation of these variables. For
example, the Water Quality Analysis Simulation Program
(WASP7) is one of the most widely used water quality
models in the United States and throughout the world
(Di Toro et al., 1983; Connolly and Winfield, 1984;
Ambrose et al., 1988). Users are able to interpret and predict water quality responses to natural phenomena and
man-made pollution for various pollution management
decisions. AQUATOX is a simulation model for aquatic
systems and predicts the fate of various pollutants, such
as nutrients and organic chemicals, and their effects on
ecosystems, including fish, invertebrates, and aquatic
plants.
Bibliography
Ambrose, R. B., et al., 1988. WASP4, A Hydrodynamic and Water
Quality Model – Model Theory, User’s Manual and Programmer’s Guide. Athens: USEPA. EPA/600/3-87-039.
APHA, Program Area Committee on Housing and Health, 1969.
Basic health principles of housing and its environment. American Journal of Public Health, 59, 841–851.
Brown, L. C., and Barnwell, T. O., 1987. The Enhanced Stream Water
Quality Models QUAL2E and QUAL2E-UNCAS: Documentation
and User Manual. Environmental Research Laboratory,
US EPA, EPA/600/3-87/007, Athens, GA.
Clean Water Act (CWA) of 1972, 33 U.S.C. } 1251 et seq., 2002,
Retrieved from http://epw.senate.gov/water.pdf
Connolly, J. P., and Winfield, R. P., 1984. A User’s Guide for
WASTOX, a Framework for Modeling the Fate of Toxic
Chemicals in Aquatic Environments. Part 1. Exposure Concentration. Gulf Breeze: USEPA. EPA-600/3-84-077.
Di Toro, D. M., Fitzpatrick, J. J., and Thomann, R. V., 1983. Water
Quality Analysis Simulation Program (WASP) and Model Verification Program (MVP) – Documentation. Hydroscience, Inc. for
U.S. EPA, Duluth, MN.
Dubrovsky, N. M., Burow, K. R., Clark, G. M., Gronberg, J. M.,
Hamilton, P. A., Hitt, K. J., Mueller, D. K., Munn, M. D.,
Nolan, B. T., Puckett, L. J., Rupert, M. G., Short, T. M.,
Spahr, N. E., Sprague, L. A., and Wilber, W. G., 2010.
The Quality of Our Nation’s Waters – Nutrients in the Nation’s
Streams and Groundwater, 1992–2004. U.S. Geological Survey
Circular 1350, 174 p. Additional information about this study
is available at http://water.usgs.gov/nawqa/nutrients/pubs/
circ1350
Gilliom, R. J. et al., 2006. The quality of our nation’s waters — pesticides in the nation’s streams and ground water, 1992–2001.
U.S. Geological Survey Circular, 1291, 172.
Horowitz, A. J., and Stephens, V. C., 2008. The effects of land use on
fluvial sediment chemistry for the conterminous U.S. – results
from the first cycle of the NAWQA Program: trace and major elements, phosphorus, carbon, and sulfur. Science of the Total Environment, 400, 290–314.
Johnson, D. L., Ambrose, S. H., Bassett, T. J., Bowen, M. L.,
Crummey, D. E., Isaacson, J. S., Johnson, D. N., Lamb, P., Saul,
M., and Winter-Nelson, A. E., 1997. Meanings of environmental
terms. Journal of Environmental Quality, 26, 581–589,
doi:10.2134/jeq1997.00472425002600030002.
Richard, P. A., and McQuisten, R., 1968. Glossary of Selected
Hydrologic Terms. Laramie: Water Resources Institute, University of Wyoming, pp. 1–53.
Sprague, L. A., Mueller, D. K., Schwarz, G. E., and Lorenz, D. L.,
2009. Nutrient Trends in Streams and Rivers of the United States,
1993–2003. U.S. Geological Survey Scientific Investigations
Report 2008–5202, 196 pp.
USEPA, 1999. Ecological Conditions of Estuaries in the Gulf of
Mexico. U.S. Environmental Protection Agency, Office of
Research and Development, National Health and Environmental
Effects Research Laboratory, Gulf Ecology Division, Gulf
Breeze, Florida. EPA 620-R-98-004
Veatch, J. O., and Humphrys, C. R., 1966. Water and Water Use
Terminology. Kaukauna: Thomas Printing & Publishing,
pp. 1–75.
Cross-references
Algal Blooms
Anoxia, Hypoxia, and Dead Zones
Biochemical Oxygen Demand
Clean Water Act
Eutrophication
Nonpoint Source Pollution
Nutrients
Oil Pollution
Oxygen Depletion
Pathogens
Water Quality
730
WATER QUALITY
beneficial use(s) of a water segment and the water
quality criteria necessary to support those uses (CWA,
1972). Water quality standards establish the environmental baselines used for measuring the health of
aquatic ecosystems.
Measuring water quality
The parameters for water quality are determined by the
intended use. Water quality is measured by several factors, such as the concentration of dissolved oxygen, bacteria levels, nutrients concentrations (commonly nitrogen
and phosphorus), amount of salt (or salinity), or the
amount of material suspended in the water (turbidity).
In some bodies of water, the microscopic algae and quantities of pesticides, herbicides, heavy metals, and other
contaminants may also be measured to determine water
quality. Parameters commonly measured in water bodies
include temperature, pH, turbidity, Secchi disk depth,
dissolved oxygen, conductivity, and oxygen reduction
potential (ORP). Biological metrics have been developed
in many places, and one widely used measure is the presence and abundance of members of the insects. Biological indexes vary from region to region; however, the
greater the number of taxa from these orders, the better
the water quality.
Water quality models
Various water quality models have been used to simulate
the fate of pollutants and the state of selected water quality
variables in water bodies. They incorporate a variety of
physical, chemical, and biological processes that control
the transport and transformation of these variables. For
example, the Water Quality Analysis Simulation Program
(WASP7) is one of the most widely used water quality
models in the United States and throughout the world
(Di Toro et al., 1983; Connolly and Winfield, 1984;
Ambrose et al., 1988). Users are able to interpret and predict water quality responses to natural phenomena and
man-made pollution for various pollution management
decisions. AQUATOX is a simulation model for aquatic
systems and predicts the fate of various pollutants, such
as nutrients and organic chemicals, and their effects on
ecosystems, including fish, invertebrates, and aquatic
plants.
Bibliography
Ambrose, R. B., et al., 1988. WASP4, A Hydrodynamic and Water
Quality Model – Model Theory, User’s Manual and Programmer’s Guide. Athens: USEPA. EPA/600/3-87-039.
APHA, Program Area Committee on Housing and Health, 1969.
Basic health principles of housing and its environment. American Journal of Public Health, 59, 841–851.
Brown, L. C., and Barnwell, T. O., 1987. The Enhanced Stream Water
Quality Models QUAL2E and QUAL2E-UNCAS: Documentation
and User Manual. Environmental Research Laboratory,
US EPA, EPA/600/3-87/007, Athens, GA.
Clean Water Act (CWA) of 1972, 33 U.S.C. } 1251 et seq., 2002,
Retrieved from http://epw.senate.gov/water.pdf
Connolly, J. P., and Winfield, R. P., 1984. A User’s Guide for
WASTOX, a Framework for Modeling the Fate of Toxic
Chemicals in Aquatic Environments. Part 1. Exposure Concentration. Gulf Breeze: USEPA. EPA-600/3-84-077.
Di Toro, D. M., Fitzpatrick, J. J., and Thomann, R. V., 1983. Water
Quality Analysis Simulation Program (WASP) and Model Verification Program (MVP) – Documentation. Hydroscience, Inc. for
U.S. EPA, Duluth, MN.
Dubrovsky, N. M., Burow, K. R., Clark, G. M., Gronberg, J. M.,
Hamilton, P. A., Hitt, K. J., Mueller, D. K., Munn, M. D.,
Nolan, B. T., Puckett, L. J., Rupert, M. G., Short, T. M.,
Spahr, N. E., Sprague, L. A., and Wilber, W. G., 2010.
The Quality of Our Nation’s Waters – Nutrients in the Nation’s
Streams and Groundwater, 1992–2004. U.S. Geological Survey
Circular 1350, 174 p. Additional information about this study
is available at http://water.usgs.gov/nawqa/nutrients/pubs/
circ1350
Gilliom, R. J. et al., 2006. The quality of our nation’s waters — pesticides in the nation’s streams and ground water, 1992–2001.
U.S. Geological Survey Circular, 1291, 172.
Horowitz, A. J., and Stephens, V. C., 2008. The effects of land use on
fluvial sediment chemistry for the conterminous U.S. – results
from the first cycle of the NAWQA Program: trace and major elements, phosphorus, carbon, and sulfur. Science of the Total Environment, 400, 290–314.
Johnson, D. L., Ambrose, S. H., Bassett, T. J., Bowen, M. L.,
Crummey, D. E., Isaacson, J. S., Johnson, D. N., Lamb, P., Saul,
M., and Winter-Nelson, A. E., 1997. Meanings of environmental
terms. Journal of Environmental Quality, 26, 581–589,
doi:10.2134/jeq1997.00472425002600030002.
Richard, P. A., and McQuisten, R., 1968. Glossary of Selected
Hydrologic Terms. Laramie: Water Resources Institute, University of Wyoming, pp. 1–53.
Sprague, L. A., Mueller, D. K., Schwarz, G. E., and Lorenz, D. L.,
2009. Nutrient Trends in Streams and Rivers of the United States,
1993–2003. U.S. Geological Survey Scientific Investigations
Report 2008–5202, 196 pp.
USEPA, 1999. Ecological Conditions of Estuaries in the Gulf of
Mexico. U.S. Environmental Protection Agency, Office of
Research and Development, National Health and Environmental
Effects Research Laboratory, Gulf Ecology Division, Gulf
Breeze, Florida. EPA 620-R-98-004
Veatch, J. O., and Humphrys, C. R., 1966. Water and Water Use
Terminology. Kaukauna: Thomas Printing & Publishing,
pp. 1–75.
Cross-references
Algal Blooms
Anoxia, Hypoxia, and Dead Zones
Biochemical Oxygen Demand
Clean Water Act
Eutrophication
Nonpoint Source Pollution
Nutrients
Oil Pollution
Oxygen Depletion
Pathogens
Water Quality
730
WATER QUALITY