Water Quality

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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

Case Studies & Factsheets


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 or...


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 underlying...

Cover of Heavy Oil

Introduction Naturally occurring crude oil comes in many forms. The most familiar to many people is light crude oil, which is less dense than water and flows easily at room temperature. Heavy oil and bitumen are forms of crude oil that are more viscous (thicker) and dense. The largest crude oil...


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 used...

Cover of Spills in Oil and Natural Gas Fields

Introduction Oilfield spills can harm wildlife and pose a risk to human health if they reach fresh water sources or contaminate soil or air. The enormous size of the oil and gas industry and the huge volumes of oil and produced water that are handled, stored, and transported result in thousands of...

Cover of Water in the Oil and Gas Industry

Introduction The oil and gas industry consumes and produces water. Water is used to drill and hydraulically fracture (“frack”) wells, refine and process oil and gas, and produce electricity in some natural gas power plants. Water is also naturally present in the rocks that contain oil and gas and...

Cover of Using Produced Water

Opportunities and Concerns in Using Produced Water Produced water is natural groundwater that is extracted along with oil and gas. It is commonly salty and mixed with oil residues,1 so it must be either disposed of or treated and reused. About 2.5 billion gallons of produced water are extracted...

Cover of Petroleum and the Environment - an Introduction

Introduction When oil and gas were first extracted and used on an industrial scale in the 19th century, they provided significant advantages over existing fuels: they were cleaner, easier to transport, and more versatile than coal and biomass (wood, waste, and whale oil). Diesel and gasoline...


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....

Cover of Geoscientists in Petroleum and the Environment

Introduction Geoscience – the study of the Earth – underpins our understanding of the many intersections between petroleum and the environment, from the search for resources to the study of air pollutants. Without the work of geoscientists, we would have neither the energy system nor the...

Cover of Groundwater Protection in Oil and Gas Production

Introduction The United States relies on groundwater for roughly 25% of its fresh water.1 This groundwater is found in porous, permeable rocks (aquifers) that often lie close to the Earth’s surface – the deepest freshwater aquifers are found more than 6,000 feet underground,2 but most are much...

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

In central Alabama, the Mississippian-age Fort Payne Chert is an important aquifer for domestic and municipal water supplies. Geologic mapping shows the extent of Fort Payne Chert exposure at the ground surface, which is the recharge area for the aquifer. Planning for protection of the groundwater...

Cover of Abandoned Wells

Introduction In 2017, there were one million active oil and gas wells in the United States.1 When a well reaches the end of its productive life, or if it fails to find economic quantities of oil or gas, the well operator is required by regulators to remove all equipment and plug the well to prevent...

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GOLI Online Courses

GOLI Course: Techniques for Developing High Resolution LNAPL Conceptual Site Models; Image courtesy of Roger Lamb
Course Type: GOLI Online Course

This course is intended for geologists involved in Light Non-Aqueous Phase Liquid (LNAPL) assessment and remediation. This course provides information on the development of high resolution conceptual site models that can be used to guarantee the project goals are met. The class will cover...

Course catalog image for Well Development in New England GOLI course. Courtesy: Ted Morine
Course Type: GOLI Online Course

This course is designed to provide water utility personnel, engineers, hydrogeologists, regulatory officials, and other interested persons an understanding about the sand and gravel and bedrock aquifers in New England, how and why well performance declines over time, and information about...

GOLI Course: Desalination as a Source of Fresh Water; Image credit: James Grellier, Licensed under Creative Commons, CC-BY-SA-3.0, http://creativecommons.org/licenses/by-sa/3.0) via Wikimedia Commons.
Course Type: GOLI Online Course

Fresh water is an increasingly scarce resource in an increasingly populous and water-intensive world. Maintaining an adequate supply of fresh water both nationally and globally will be one of the largest challenges of the 21st century. Desalination of salty water, from both the ocean and the...

Cover of Bedrock Wells Exploration and Development course
Course Type: GOLI Online Course

This course provides a straightforward, informational "building block" approach to a working understanding of bedrock wells. Essential information will be presented with the goal of providing a thorough, yet realistic, understanding of bedrock wells, and in particular, enhanced awareness of the...

GOLI Course: Converting Membrane Interface Probe Sensor Results into VOC NAPL Distribution Information. Image courtesy of Roger Lamb
Course Type: GOLI Online Course

This course will focus on how to use Membrane Interface Probe sensor results in combination with soil and groundwater analytical results to map the distribution of volatile organic chemical non aqueous phase liquids. This course covers guidelines for using direct sensing tools such as the MIHPT...

Geological Surveys Database Publications

2007, United States Geological Survey

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2001, United States Geological Survey

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1989, Illinois State Geological Survey

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1979, Oklahoma Geological Survey

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2003, Georgia Geologic Survey

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1999, Colorado Geological Survey

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1986, Alaska Division of Geological & Geophysical Surveys

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1997, Georgia Geologic Survey

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1996, Georgia Geologic Survey

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1997, Georgia Geologic Survey

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