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Water Quality

What is in that water that you just drank? Is it just hydrogen and oxygen atoms? Is it safe for drinking? All water is of a certain "quality" (and you can't tell by just looking), but what does "water quality" really mean? Water full of dirt and grime might work fine for a tomato plant but would you want to drink it? Water quality can be thought of as a measure of the suita

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Downloadable Products

The U.S. Geological Survey (USGS) offers you the most comprehensive information about the natural water cycle anywhere, and, our information is available in many languages. Here you can download our water cycle diagrams as well as other educational products to assist you in the classroom or on your own learning adventure!
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Downloadable Products

The U.S. Geological Survey (USGS) offers you the most comprehensive information about the natural water cycle anywhere, and, our information is available in many languages. Here you can download our water cycle diagrams as well as other educational products to assist you in the classroom or on your own learning adventure!
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pH and Water

pH is a measure of how acidic/basic water is. The range goes from 0 to 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base. The pH of water is a very important measurement concerning water quality.
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pH and Water

pH is a measure of how acidic/basic water is. The range goes from 0 to 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base. The pH of water is a very important measurement concerning water quality.
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Water Quality Questions & Answers

What is in that water that you just drank? Is it just hydrogen and oxygen atoms? Is it safe for drinking? All water is of a certain "quality" (and you can't tell by just looking), but what does "water quality" really mean? It can be thought of as a measure of the suitability of water for a particular use based on selected physical, chemical, and biological characteristics. Here at the Water...
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Water Quality Questions & Answers

What is in that water that you just drank? Is it just hydrogen and oxygen atoms? Is it safe for drinking? All water is of a certain "quality" (and you can't tell by just looking), but what does "water quality" really mean? It can be thought of as a measure of the suitability of water for a particular use based on selected physical, chemical, and biological characteristics. Here at the Water...
Learn More

Desalination

Humans cannot drink saline water, but, saline water can be made into freshwater, for which there are many uses. The process is called "desalination", and it is being used more and more around the world to provide people with needed freshwater.
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Desalination

Humans cannot drink saline water, but, saline water can be made into freshwater, for which there are many uses. The process is called "desalination", and it is being used more and more around the world to provide people with needed freshwater.
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Acid Rain and Water

Depending on where you live, maybe you've heard of acid rain. Now, acid rain is not pure acid falling from the sky, but rather it is rainfall or atmospheric moisture that has been mixed with elements and gases that have caused the moisture to become more acidic than normal. Pure water has a pH of 7, and, generally, rainfall is somewhat on the acidic side (a bit less than 6). But, acid rain can...
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Acid Rain and Water

Depending on where you live, maybe you've heard of acid rain. Now, acid rain is not pure acid falling from the sky, but rather it is rainfall or atmospheric moisture that has been mixed with elements and gases that have caused the moisture to become more acidic than normal. Pure water has a pH of 7, and, generally, rainfall is somewhat on the acidic side (a bit less than 6). But, acid rain can...
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The Water Science School -- What We Offer

The U.S. Geological Survey's Water Science SchoolWhere anyone of any age can learn all about water.
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The Water Science School -- What We Offer

The U.S. Geological Survey's Water Science SchoolWhere anyone of any age can learn all about water.
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Water Science Photo Galleries

Learn about water using pictures
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Water Science Photo Galleries

Learn about water using pictures
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Water Q&A: How is sewage and wastewater treated?

Learn about different sewage and wastewater treatment methods.
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Water Q&A: How is sewage and wastewater treated?

Learn about different sewage and wastewater treatment methods.
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Water Q&As: Why does my water smell like rotten eggs?

Learn about the causes of bad-smelling water and what you can do about it.
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Water Q&As: Why does my water smell like rotten eggs?

Learn about the causes of bad-smelling water and what you can do about it.
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Water Q&As: How does our swimming pool stay so clean?

Learn about different methods to keep swimming pool water clean and safe.
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Water Q&As: How does our swimming pool stay so clean?

Learn about different methods to keep swimming pool water clean and safe.
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Water Q&A: What causes fish kills?

Find out more about the causes of fish kills, including dissolved oxygen and toxins.
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Water Q&A: What causes fish kills?

Find out more about the causes of fish kills, including dissolved oxygen and toxins.
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Water Q&A: Is groundwater always clean?

Learn about groundwater quality and potential contaminants.
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Water Q&A: Is groundwater always clean?

Learn about groundwater quality and potential contaminants.
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