Water Quality

Learn what happens at a wastewater treatment plant.

Water Questions & Answers Is saline water useful?

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

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

La Ciencia del Agua para Escuelas

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.

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 ecosystems...

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...

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.

There are many pieces of equipment, both mechanical and electronic, that are installed at stream-monitoring sites all around the world to measure, record, and transmit both water-quantity and water-quality information. The U.S. Geological Survey (USGS) monitors "real-time" streamflow and water-quality conditions for thousands of streams nationwide.

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.

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.