Water Quality

Water quality refers to whether water is suitable for a certain purpose, like drinking or irrigation. Both natural and man-made factors can affect water quality. Contaminants can include bacteria, metals, and man-made chemicals like pesticides or pharmaceutical drugs.


Water sampling for quality assessment in Pakistan. Image Credit: Centers for Disease Control and Prevention

Water quality is a measurement of how suitable water is for a particular use, like drinking or irrigation. Drinking water quality standards are based on the health effects that are likely to occur if a person is exposed to poor water. Industrial or agricultural water supplies will require different water standards. Water contaminants can be natural or man-made. Contaminants can include bacteria, metals, and man-made chemicals like pesticides or pharmaceutical drugs. Other natural properties of water can affect its quality, such as pH and dissolved minerals (such as salts or calcium).[1] Contamination can also alter these natural properties.   Read more

Frequently Asked Questions

American Geosciences Institute
American Geosciences Institute
American Geosciences Institute

Latest News

Atlean Lake in British Columbia
September 27, 2017 In recent years, massive harmful algal blooms (HABs) have devastated critical habitats along the Florida coasts and Great Lakes. These phenomena can cause significant “dead zones” and disastrous consequences for ecosystems and economies, resulting in economic losses from multi-...
Atlean Lake in British Columbia
April 26, 2017 On April 26, the Senate Committee on Environment and Public Works (EPW) held an oversight hearing to review the Obama Administration’s Waters of the United States (WOTUS) rule. The WOTUS rule, also known as the Clean Water Rule, was established to provide a more clear definition of...
Atlean Lake in British Columbia
April 4, 2017 The U.S. Geological Survey (USGS) hosted a briefing on April 4 to discuss the economic and public health impacts of harmful algal blooms. An algal bloom is a rapid accumulation of algae in freshwater or marine systems. It can be caused by various different species, both harmful and...
Atlean Lake in British Columbia
March 16, 2017 Representative Scott Peters (D-CA-52) introduced the Secure and Resilient Water Systems Act (H.R.1579) on March 16. The bill would help communities protect their drinking water systems from drought, industrial pollution, and potential attacks. The bill amends the Safe Drinking Water...
IES Water Glyph
February 15, 2017 On February 15, Congressman Frank Pallone, Jr. (D-NJ-6) introduced an amendment  (H.R.1068) to the Safe Drinking Water Act, which was last amended in 1996. H.R.1068 would update laws, direct the Environmental Protection Agency (EPA) to set deadlines for the development of new...
Nuclear power plant, Czech Republic
February 16, 2017 Rep. Keith Rothfus (R-PA-12) introduced legislation (H.R.1119) to modify existing regulations applying to coal-refuse-to-energy power plants on February 16. The bill acts to exempt these specific power plants from emission standards required under the Environmental Protection...
IES Water Glyph
February 7, 2017 Senators Mike Crapo (R-ID) and Claire McCaskill (D-MO) introduced the Sensible Environment Protection Act (S.340) on February 7. The act will remove an Environmental Protection Agency (EPA) regulation requiring permits for pesticide spraying over or near waterways. This bill will...
Salt marsh near Pescadero, California
January 30, 2017 On January 30, the House passed Joint Resolutions H.J.Res.38 and H.J.Res.36, expressing disapproval of the Stream Protection Rule and a rule regulating natural gas leaks. These Department of Interior (DOI) regulations are subject to termination under the Congressional Review Act....
IES Water Glyph
January 11, 2017 Representatives David Trott (R-MI-11), Debbie Dingell (D-MI-12), and Jack Bergman (R-MI-1) introduced the “Preserve Our Lakes and Keep Our Environment Safe Act” (H.R. 458) on January 11. This bill calls on the Department of Transportation (DOT) to conduct a study assessing...
An earthquake-resistant pipeline crossing the San Andreas Fault at Cholame, California. Image Copyright © Michael Collier http://www.earthscienceworld.org/images
On Thursday and Friday, December 1-2, the National Academies' Roundtable on Unconventional Hydrocarbons held a workshop on Unconventional Hydrocarbon Development: Legacy Issues, Induced Seismicity, and Innovations in Managing Risk. The meeting brought together experts from industry, academia, state...

Case Studies & Factsheets


Why water storage? A reliable water supply is essential for economic, environmental, and public health, but natural water supplies vary with the seasons and between years. Water storage, whether in reservoir lakes or underground, helps to ensure that water is available even during droughts....


The Need for Groundwater Management: Sustaining water supplies and preventing hazards In California, surface water from rainfall, snowmelt, and distant rivers rarely meets the state’s urban and agricultural water needs. Groundwater is an essential water source, providing 35% of the fresh water...


Introduction Dry wells improve stormwater drainage and aquifer recharge by providing a fast, direct route for rainwater to drain deep into underlying sediment and rock. Dry wells are most common in the western U.S. where clay or caliche layers slow down the natural drainage of water into...


What is a Dry Well? A dry well is a well that is used to transmit surface water underground and is deeper than its width at the surface (see image, below). Most dry wells are 30 to 70 feet deep and 3 feet wide at the surface. They are lined with perforated casings and can be filled with gravel...

Fig. 1 - The geologic map of part of the Pell City quadrangle, AL, accurately identifies the recharge area of the Fort Payne Chert aquifer (medium blue) that must be protected from pollution. Credit: W. Thomas

Defining the Problem In central Alabama, the Mississippian-age Fort Payne Chert is an important aquifer for domestic and municipal water supplies. Rainfall recharges groundwater where the chert is exposed at the land surface. Where the chert has been quarried, many of the abandoned pits have...

Research Database Publications

Cover for USGS FS 2014-3117 ; Source: USGS
2014, U.S. Geological Survey (USGS)
Hydrologists, geographers, geophysicists, and geologists with the U.S. Geological Survey (USGS) Texas Water Science Center (TXWSC) work in the USGS Water Mission Area on a diverse range of projects built on a foundation of spatial data. The TXWSC has developed sophisticated data and spatial-studies...
Cover image for WFS 2010-10 ; Source: Iowa Geological Survey
2009, Iowa Geological Survey (IGS)
Water quality parameters for Iowa’s stream sites.
Cover image for TIS-47 ; Source: Iowa Geological Survey
2004, Iowa Geological Survey (IGS)
Inputs and outputs of nitrogen and phosphorous were estimated for the state of Iowa and 68 of its major watersheds. Included in the input estimates are nutrients from fertilizer, legumes, soil processes, manure, atmospheric deposition, and human and industrial waste discharges. Output estimates...
Cover image for WFS 2004-8 ; Source: Iowa Geological Survey
2004, Iowa Geological Survey (IGS)
Water quality parameters for Iowa’s stream sites.
Cover of UR-52 ; Source: South Dakota Geological Survey
1989, South Dakota Geological Survey (SDGS)
This report contains the results of a ground-water investigation, conducted by the South Dakota Geological Survey, for the city of Hoven, Walworth County, South Dakota. Field work was conducted from May 27 to June 3, 1983, and on June 18 and 19, 1984. The investigation included the drilling of 16...
Cover of FS078-00; Source: USGS
2000, U.S. Geological Survey (USGS)
To evaluate the vulnerability of the city's drinking-water supply to contaminants from the Elkhorn and Platte Rivers, the U.S. Geological Survey conducted several studies in cooperation with the city of Lincoln from 1991 to 2000. This fact sheet summarizes selected results from those studies;...
Cover of MBMG 658; Source: Montana Bureau of Mines and Geology (MBMG)
2015, Montana Bureau of Mines and Geology (MBMG)
Montana and the surrounding states have a unique geology that presents many opportunities for valuable continuing research on mineral deposits. Research centered on economic geology and mineralogy can lead to a better understanding of the mineral deposits in this region, and thus the discovery of...
Cover image for WFS 2004-9 ; Source: Iowa Geological Survey
2004, Iowa Geological Survey (IGS)
Considerable national and local interest continues to be focused on Eastern Iowa surface water quality. A recent study by the U.S. Geological Survey of Mississippi River watersheds ranks the Iowa River and Cedar River 2nd and 3rd highest out of 42 river systems, respectively, in average nitrate-N (...
Cover image for TIS-40 ; Source: Iowa Geological Survey
1999, Iowa Geological Survey (IGS)
Since 1984, the Iowa Department of Natural Resources - Geological Survey Bureau has monitored the effects of agricultural drainage wells (ADWs) on groundwater quality in three Devonian bedrock aquifer units beneath central Floyd County. Results from a nest of four bedrock piezometers drilled to...
Autumn Foliage in the Adirondacks, New York, USA
2012, American Geosciences Institute (AGI)
Every Tuesday at 9 a.m., Dave Warner collects water from a white plastic 3.5-gallon tub that sits on a strip of tall grass between two cornfields at the University of Nebraska Agricultural Research and Development Center near Mead, Neb. For more than 30 years, the bucket has collected all forms of...