Water Quality

Corrosivity describes how aggressive water is at corroding pipes and fixtures. Corrosive water can cause lead and copper in pipes to leach into drinking water and can eventually cause leaks in plumbing. Surface water and groundwater, both sources of drinking water, can potentially be corrosive.

Are you among the more than 100 million people in the U.S. who relies on a public-supply well for your drinking water? Although the quality of finished drinking water from public water systems is regulated by the EPA, long-term protection and management of the raw groundwater tapped by public-supply wells requires an understanding of the occurrence of contaminants in this invisible, vital resource...

More than 43 million people—about 15 percent of the U.S. population—rely on domestic (private) wells as their source of drinking water. The quality and safety of water from domestic wells are not regulated by the Federal Safe Drinking Water Act or, in most cases, by state laws. Instead, individual homeowners are responsible for maintaining their domestic well systems and for monitoring water...

The National Field Manual for the Collection of Water-Quality Data (NFM) provides documented methods and protocols for USGS field personnel who collect water-quality data. The NFM provides detailed, comprehensive, and citable procedures for sampling water resources, processing samples for analysis of water quality, measuring field parameters, and specialized procedures.

The clams Potamocorbula amurensis and Corbicula fluminea were collected at a variety of sites in the San Francisco Bay/ Delta beginning July 1990 and ending February 2010. These invasive species were used as biosentinels of the fate, transport, and effects of trace metals in the San Francisco Bay ecosystem.

What’s in your groundwater? Learn about groundwater quality in the Principal Aquifers of nine regions across the United States in informative circulars filled with figures, photos, and water-quality information.

This searchable online database provides Health-Based Screening Levels (HBSLs) for hundreds of chemicals, including pesticides and degradates. HBSLs are non-enforceable benchmark concentrations of contaminants in water. These screening levels supplement federal drinking-water standards and guidelines.

The USGS is undertaking a 3-year study of water use, availability, and change in the Red River basin, which covers more than 93,000 square miles in New Mexico, Texas, Oklahoma, Arkansas, and Louisiana. Water resources are being stressed by increasing water demands and increasingly severe droughts, and a comprehensive water-resource assessment of the basin is needed to enable sustainable water use.

Is groundwater the source of your drinking water? The USGS is assessing the quality of groundwater used for public supply using newly collected data along with existing water-quality data. Learn more about this invisible, vital resource so many of us depend on.

We think of groundwater as moving slowly, and groundwater quality as changing slowly—over decades or even centuries. But in some parts of some aquifers, groundwater quality can fluctuate rapidly, sometimes over just a few hours. Are such changes part of a long-term trend, or just part of a short-term cycle? And what does that mean for suitability for drinking?

Groundwater provides nearly one-half of the Nation’s drinking water, and sustains the steady flow of streams and rivers and the ecological systems that depend on that flow. Unless we drill a well, how can we know the quality of the groundwater below? Learn about how the USGS is using sophisticated techniques to predict groundwater quality and view national maps of groundwater quality.

More than 100 million people in the United States—about 35 percent of the population—receive their drinking water from public-supply wells. These systems can be vulnerable to contamination from naturally occurring constituents, such as radon, uranium and arsenic, and from commonly used manmade chemicals, such as fertilizers, pesticides, solvents, and gasoline hydrocarbons. Learn about the...