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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.

The Basics

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.

Why does water quality matter?

Contaminants are harmful to human health, especially to vulnerable populations such as the elderly or the very young. The quality of a stream or wetland affects everyone’s health, from the plants and animals that live in it to the people who live downstream. If water is unsuitable for a particular purpose, we have to find alternative resources, sometimes at high cost.

How does geoscience help inform decisions on water quality?

Geoscientists monitor the quality of surface water and ground water for society’s needs, especially for human consumption. They find the origin of natural and man-made contaminants, and determine ways to remove them.

References

1 U.S. Geological Survey, 2001, “A Primer on Water Quality”

Learn More

Introductory Resources

  • A Primer on Water Quality, U.S. Geological Survey
    A basic overview of water quality, how it is measured, and how natural and human processes affect it.

  • Surf Your Watershed, Environmental Protection Agency
    Searchable data hub allowing users to find information on water quality and other environmental information for watersheds across the United States

Resources for Educators

Additional Resources

Drought

Since 1980 the United States has experienced more than 24 major droughts, resulting in almost 3,000 deaths and economic impacts exceeding $225 billion.All areas of the U.S. have some drought risk.

Groundwater

Groundwater is the water found underground in the cracks and spaces in soil, sand, and rock. Groundwater has been used by humans for thousands of years; today it provides 25% of the fresh water used in the United States, mostly for irrigation and public water supplies.

Waste Management

Although our industrial society produces a variety of solid wastes and waste waters, over the past 50 years we have made progress in disposing of them safely in landfills, by incineration, and in underground injection wells. Many wastes are also increasingly recycled or reused.

Water

Water is essential for society and, as demand steadily rises, our most precious commodity. Geoscientists study how to provide a clean and secure water source to meet society’s needs.

Water Availability

Water is constantly moving on the Earth between the atmosphere, ocean, rivers and streams, snowpacks and ice sheets, and underground. Water availability, both as surface water and groundwater, is essential for agriculture, human consumption, industry, and energy generation.

Wildfires

Wildfires are causing more frequent and wider-ranging societal impacts, especially as residential communities continue to expand into wildland areas. Since 2000, there have been twelve wildfires in the United States that have each caused damages exceeding $1 billion; cumulatively, these twelve wildfires have caused a total of $44 billion in damages.