Water Science School

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 suitability of water for a particular use based on selected physical, chemical, and biological characteristics

All Water Quality Science Topics

All Water Quality Science Topics

View a list of all of our science topics about water quality.

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Water Quality Data for the Nation

Water Quality Data for the Nation

The USGS National Water Information System (NWIS) contains extensive water-quality data, both real-time and historical, for the nation.

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Filter Total Items: 44
Date published: June 20, 2019
Status: Completed

Water Q&A: Is saline water useful?

Water Questions & Answers
Is saline water useful?

Contacts: Ask USGS
Date published: June 20, 2019
Status: Completed

Water Q&A: What water data does the USGS gather?

The USGS collects data about the country's water resources including the quantity and quality of water in our streams, rivers, groundwater, and more.

Contacts: Ask USGS
Date published: April 2, 2019
Status: Completed

Water Q&A: Why can't I rinse the soap off my hands

Water Quality Q&A:
Why can't I rinse the soap off my hands?

Contacts: Ask USGS
Date published: April 2, 2019
Status: Completed

La Ciencia del Agua para Escuelas

La Ciencia del Agua para Escuelas

Contacts: Ask USGS
Date published: February 6, 2019
Status: Completed

Groundwater Quality

Even though the ground is an excellent mechanism for filtering out particulate matter, such as leaves, soil, and bugs, dissolved chemicals and gases can still occur in large enough concentrations in groundwater to cause problems.

Contacts: Ask USGS
Date published: November 13, 2018
Status: Completed

Mercury Contamination of Aquatic Environments

Mercury has got to be one of the most fascinating elements around. In looking at the bubbles of bright silver sitting on a flat surface, it is easy to see why mercury is also called "quicksilver." Mercury is the only metal that exists in liquid form. It may act somewhat like water, but it is nothing at all like water, especially in the potential harmful effects it can have on humans and...

Contacts: Ask USGS
Date published: November 13, 2018
Status: Completed

Water Quality Information by Topic

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 suitability of water for...

Contacts: Ask USGS
Date published: October 26, 2018
Status: Completed

Water Science Activity Center

This is the interactive section of our site where you can answer challenge questions, participate in opinion surveys about water issues, and take true/false quizzes.

Contacts: Ask USGS
Date published: June 18, 2018
Status: Completed

A Visit to a Wastewater Treatment Plant

Have you ever wondered what happens to that water and waste after you flush? How about after you pull the plug on your tub? The modern wastewater-treatment plant employs basic physics and high technology to purify the dirtiest of water so it can go back into the environment as a member in good standing of the water cycle.

 

Contacts: Ask USGS
Date published: June 18, 2018
Status: Completed

Wastewater Treatment Water Use

Wastewater is used water. It includes substances such as human waste, food scraps, oils, soaps and chemicals. In homes, this includes water from sinks, showers, bathtubs, toilets, washing machines and dishwashers. Businesses and industries also contribute their share of used water that must be cleaned.

Contacts: Ask USGS
Date published: June 12, 2018
Status: Completed

Urbanization and Water Quality

There's no end to the effects that urbanization can have on water bodies. Millions of people; landscape manipulation; waste material; dumping of chemicals and fertilizers; withdrawing water for peoples' uses. As you expect, urbanization rarely improves water quality, but in order to prevent problems, one needs to understand how urbanization affects the local waters.

Contacts: Ask USGS
Date published: June 11, 2018
Status: Completed

Saline Water and Salinity

In your everyday life you are not involved much with saline water. You are concerned with freshwater to serve your life's every need. But, most of Earth's water, and almost all of the water that people can access, is saline, or salty water. Just look at the oceans and remember that oceans comprise about 97% of all water on, in, and above the Earth.

Contacts: Ask USGS