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Water

The USGS monitors and studies a wide range of water resources and water conditions, including streamflow, groundwater, water quality, and water use and availability.

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How much natural water is there? How much natural water is there?

Earth is estimated to hold about 1,386,000,000 cubic kilometers of water. The breakdown of where all that water resides is estimated as follows: Oceans (saline) 1,338,000,000 cubic kilometers Ice caps and glaciers (fresh) 24,064,000 cubic kilometers Groundwater (fresh and saline) 23,400,000 cubic kilometers Streams, lakes, swamps (fresh) 104,590 cubic kilometers Lakes (saline) 85,400 cubic...

How much natural water is there?

How much natural water is there?

Earth is estimated to hold about 1,386,000,000 cubic kilometers of water. The breakdown of where all that water resides is estimated as follows: Oceans (saline) 1,338,000,000 cubic kilometers Ice caps and glaciers (fresh) 24,064,000 cubic kilometers Groundwater (fresh and saline) 23,400,000 cubic kilometers Streams, lakes, swamps (fresh) 104,590 cubic kilometers Lakes (saline) 85,400 cubic...

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Why is our porcelain sink stained brown? Why is our porcelain sink stained brown?

The brown stain is from a large amount of iron in your water. It is closely related to simple rust that you see on metal, which is iron oxide. Your water probably comes from groundwater that filtered through rocks containing iron-rich minerals on its way to the well. Learn more: Water Color USGS Drinking Water and Source Water Research

Why is our porcelain sink stained brown?

Why is our porcelain sink stained brown?

The brown stain is from a large amount of iron in your water. It is closely related to simple rust that you see on metal, which is iron oxide. Your water probably comes from groundwater that filtered through rocks containing iron-rich minerals on its way to the well. Learn more: Water Color USGS Drinking Water and Source Water Research

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Why does my drinking water look cloudy sometimes? Why does my drinking water look cloudy sometimes?

Once in a while you get a glass of water that looks cloudy; maybe milky is a better term. After a few seconds it miraculously clears up! The cloudiness is due to tiny air bubbles in the water. Like any bubbles, the air rises to the top of the water and goes into the air, clearing up the water. The water in the pipes coming into your house might be under a bit of pressure. This causes gases (air)...

Why does my drinking water look cloudy sometimes?

Why does my drinking water look cloudy sometimes?

Once in a while you get a glass of water that looks cloudy; maybe milky is a better term. After a few seconds it miraculously clears up! The cloudiness is due to tiny air bubbles in the water. Like any bubbles, the air rises to the top of the water and goes into the air, clearing up the water. The water in the pipes coming into your house might be under a bit of pressure. This causes gases (air)...

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Why does it take so long to rinse the soap off my hands? What are hard water and soft water? Why does it take so long to rinse the soap off my hands? What are hard water and soft water?

Water is said to be soft if it has a low concentration of calcium and magnesium ions in it, while hard water has a high concentration of calcium and magnesium. The minerals in hard water often react with most soaps to create a "soap scum," which is an insoluble substance that can temporarily adhere to your hands or the shower walls. When using hard water, you may have a harder time working your...

Why does it take so long to rinse the soap off my hands? What are hard water and soft water?

Why does it take so long to rinse the soap off my hands? What are hard water and soft water?

Water is said to be soft if it has a low concentration of calcium and magnesium ions in it, while hard water has a high concentration of calcium and magnesium. The minerals in hard water often react with most soaps to create a "soap scum," which is an insoluble substance that can temporarily adhere to your hands or the shower walls. When using hard water, you may have a harder time working your...

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Where can I find information about my local drinking water supply? Where can I find information about my local drinking water supply?

The best way to learn about your local drinking water quality is to read the annual drinking water quality report/consumer confidence report that water suppliers now send out by July 1 of each year. The reports are often sent out with water bills, but they may be sent separately. The reports tell where drinking water comes from, what contaminants are in it, and at what levels. The U.S...

Where can I find information about my local drinking water supply?

Where can I find information about my local drinking water supply?

The best way to learn about your local drinking water quality is to read the annual drinking water quality report/consumer confidence report that water suppliers now send out by July 1 of each year. The reports are often sent out with water bills, but they may be sent separately. The reports tell where drinking water comes from, what contaminants are in it, and at what levels. The U.S...

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Where can I find information about bottled water? Where can I find information about bottled water?

Bottled water is regulated by the U.S. Food and Drug Administration and by individual states. For general information about bottled water, sources include the International Bottled Water Association and NSF International. Learn More: Water bottling across the U.S. - interactive map Water Use - Withdrawals for Bottled Water

Where can I find information about bottled water?

Where can I find information about bottled water?

Bottled water is regulated by the U.S. Food and Drug Administration and by individual states. For general information about bottled water, sources include the International Bottled Water Association and NSF International. Learn More: Water bottling across the U.S. - interactive map Water Use - Withdrawals for Bottled Water

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What can cause our water to have an earthy odor or to smell like rotten eggs? What can cause our water to have an earthy odor or to smell like rotten eggs?

Naturally-occurring organic compounds are created when plant material decays in lakes and reservoirs. Those organic compounds frequently cause musty, earthy odors, especially toward the end of summer. The odors can be objectionable, but generally are not harmful to health. However, odors can be caused by other constituents as well, so you might want to call your local Health Department and mention...

What can cause our water to have an earthy odor or to smell like rotten eggs?

What can cause our water to have an earthy odor or to smell like rotten eggs?

Naturally-occurring organic compounds are created when plant material decays in lakes and reservoirs. Those organic compounds frequently cause musty, earthy odors, especially toward the end of summer. The odors can be objectionable, but generally are not harmful to health. However, odors can be caused by other constituents as well, so you might want to call your local Health Department and mention...

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Does the use of pesticides affect our Nation's water quality? Does the use of pesticides affect our Nation's water quality?

Pesticide use in the United States has increased because not only must we supply our exploding population with food, but crops and food are also grown for export to other countries. The United States has become the largest producer of food products in the world, partly owing to our use of modern chemicals (pesticides) to control the insects, weeds, and other organisms that attack food crops. But...

Does the use of pesticides affect our Nation's water quality?

Does the use of pesticides affect our Nation's water quality?

Pesticide use in the United States has increased because not only must we supply our exploding population with food, but crops and food are also grown for export to other countries. The United States has become the largest producer of food products in the world, partly owing to our use of modern chemicals (pesticides) to control the insects, weeds, and other organisms that attack food crops. But...

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How is the salinity of Great Salt Lake measured? How is the salinity of Great Salt Lake measured?

The salinity of Great Salt Lake is measured by taking specific gravity and temperature measurements and comparing them to standardized values reported in a table. Specific gravity is measured in the field by testing a water sample with a device very similar to a battery or antifreeze tester. Learn more: Water-Resources Investigations Report for Great Salt Lake, Utah

How is the salinity of Great Salt Lake measured?

How is the salinity of Great Salt Lake measured?

The salinity of Great Salt Lake is measured by taking specific gravity and temperature measurements and comparing them to standardized values reported in a table. Specific gravity is measured in the field by testing a water sample with a device very similar to a battery or antifreeze tester. Learn more: Water-Resources Investigations Report for Great Salt Lake, Utah

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Is saline water used for anything? Is saline water used for anything?

In the U.S., about 13 percent of all water used is saline water. But saline water can only be used for certain purposes. The main use is for thermoelectric power-plant cooling. About 5 percent of water used for industrial purposes is saline, and about 53 percent of all water used for mining purposes is saline. Saline water can be desalinated for use as drinking water by putting it through a...

Is saline water used for anything?

Is saline water used for anything?

In the U.S., about 13 percent of all water used is saline water. But saline water can only be used for certain purposes. The main use is for thermoelectric power-plant cooling. About 5 percent of water used for industrial purposes is saline, and about 53 percent of all water used for mining purposes is saline. Saline water can be desalinated for use as drinking water by putting it through a...

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What can be causing our drinking water to have a reddish color? What can be causing our drinking water to have a reddish color?

Your water might be affected by iron, which is a commonly-occurring constituent of drinking water. Iron tends to add a rusty, reddish-brown (or sometimes yellow) color to water. If the color is more black than red, your water might contain a combination of iron and manganese. Both of these metals can cause staining of plumbing fixtures or laundry, but they are not known to cause health problems...

What can be causing our drinking water to have a reddish color?

What can be causing our drinking water to have a reddish color?

Your water might be affected by iron, which is a commonly-occurring constituent of drinking water. Iron tends to add a rusty, reddish-brown (or sometimes yellow) color to water. If the color is more black than red, your water might contain a combination of iron and manganese. Both of these metals can cause staining of plumbing fixtures or laundry, but they are not known to cause health problems...

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Do you have information about water hardness in the United States? Do you have information about water hardness in the United States?

See the USGS map of water hardness (as calcium carbonate) in surface water of the United States. Under the Safe Drinking Water Act, primarily administered by the U.S. Environmental Protection Agency (EPA), your drinking water supplier is required to send you information about the quality of your drinking water every year. These annual drinking water quality reports (also known as consumer...

Do you have information about water hardness in the United States?

Do you have information about water hardness in the United States?

See the USGS map of water hardness (as calcium carbonate) in surface water of the United States. Under the Safe Drinking Water Act, primarily administered by the U.S. Environmental Protection Agency (EPA), your drinking water supplier is required to send you information about the quality of your drinking water every year. These annual drinking water quality reports (also known as consumer...

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