Water Resources

Measuring and Monitoring Water

Hydrologic Instrumentation Facility (HIF)

Hydrologic Instrumentation Facility (HIF)

The HIF provides quality hydrologic equipment and instrumentation

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Streamgaging Basics

Streamgaging Basics

The USGS has a nationwide network of over 8,500 sites that measure streamflow and water levels.

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Filter Total Items: 153
Date published: February 28, 2019
Status: Active

Groundwater Quality—Current Conditions and Changes Through Time

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.

Contacts: Bruce Lindsey
Date published: February 28, 2019
Status: Active

Rapid Fluctuations in Groundwater Quality

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?

Date published: February 28, 2019
Status: Active

Predicting Groundwater Quality in Unmonitored Areas

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.

Date published: February 28, 2019
Status: Completed

Factors Affecting Vulnerability of Public-Supply Wells to Contamination

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...

Contacts: Sandra Eberts
Date published: February 27, 2019
Status: Active

Groundwater Age

The age of groundwater is key in predicting which contaminants it might contain. There are many tracers and techniques that allow us to estimate the age—or mix of ages—of the groundwater we depend on as a drinking water supply. 

Date published: February 27, 2019
Status: Active

Surface-Water Quality and Ecology

Research by the USGS National Water Quality Assessment (NAWQA) Project on water quality of rivers and streams covers a broad range of topics, from nonpoint pollution issues to vulnerability of aquatic ecosystems. Dive in and find out more about current water-quality conditions, how and where water quality is changing, and the latest information on pesticides, nutrients, and other contaminants...

Date published: February 27, 2019
Status: Active

Estimated Annual Agricultural Pesticide Use

These tables, maps, and graphs provide estimates of U.S. agricultural pesticide use suitable for evaluating national and regional patterns and trends of annual pesticide use.

Attribution: Water Resources
Date published: February 27, 2019
Status: Active

Water-Quality Trends From Lake Cores

Sediment cores let us look back in time at the contaminant history of a watershed. Learn about what lake and reservoir sediment cores tell us about trends in metals, organochlorine pesticides, polycyclic aromatic hydrocarbons, and other sediment-related contaminants.

Attribution: Water Resources
Date published: February 27, 2019
Status: Active

Volatile Organic Compounds (VOCs)

Volatile organic compounds (VOCs) are chemicals that both vaporize into air and dissolve in water. VOCs are pervasive in daily life, because they’re used in industry, agriculture, transportation, and day-to-day activities around the home. Once released into groundwater, many VOCs are persistent and can migrate to drinking-water supply wells.

Contacts: Bruce Lindsey
Date published: February 27, 2019
Status: Active

Oxidation/Reduction (Redox)

The redox state of groundwater—whether the groundwater is oxic (oxidized) or anoxic (reduced)—has profound implications for groundwater quality.  Knowing the redox conditions of groundwater can help determine whether it contains elevated levels of many contaminants, including arsenic, nitrate, and even some manmade contaminants.

Contacts: Peter B McMahon
Date published: February 27, 2019
Status: Active

Everything you need to know about SPARROW

What is SPARROW? SPARROW (SPAtially Referenced Regression On Watershed attributes) is a watershed modeling technique for relating water-quality measurements made at a network of monitoring stations to attributes of the watersheds such as contaminant sources and environmental factors that affect rates of delivery to streams and in-stream processing. The core of the model...

Date published: February 27, 2019
Status: Archived

SPARROW: Nutrients and the Nation's Estuaries

Tracking the Source and Quantity of Nutrients to the Nation's Estuaries (archived) provides maps and data of watershed nutrient contributions to the Nation's estuaries estimated using SPARROW (SPAtially Referenced Regressions On Watershed attributes) models.

Attribution: Water Resources