Water Resources

Types of Water

The Water Cycle

The Water Cycle

Water is constantly moving through the hydrologic cycle

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Rivers, Streams, and Creeks

Rivers, Streams, and Creeks

Water quality data from state, federal, tribal, and local agencies

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Filter Total Items: 148
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

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: 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
Date published: February 27, 2019
Status: Active

Linking Selenium Sources to Ecosystems: Irrigation

Adverse effects of selenium (Se) on fish and waterfowl in wetlands receiving agricultural drainage occurred in the 1980s in the San Joaquin Valley of California. The identified mechanisms of Se enrichment helped resolve Se toxicity problems associated with irrigated agriculture in the arid West. Bioaccumulation of Se in ancient marine sediments is postulated as a primary pathway in source...

Contacts: Theresa Presser, Joseph P. Skorupa
Attribution: Water Resources
Date published: February 27, 2019
Status: Active

Linking Selenium Sources to Ecosystems: Refining

The San Francisco Bay-Delta receives selenium (Se) internally from oil refineries and externally through riverine agricultural discharges. Predator species considered at risk from Se consume the estuary’s dominant bivalve, C. amurensis, an efficient bioaccumulator of Se. Modeling predicts site-specific ecological risk and derives a range of protective Se concentrations for use by decision-...

Contacts: Theresa Presser, Joseph P. Skorupa
Attribution: Water Resources
Date published: February 27, 2019
Status: Completed

National Water-Quality Assessment (NAWQA): 1991-2012

In 1991, Congress established the National Water-Quality Assessment (NAWQA) Project to address where, when, why, and how the Nation's water quality has changed, or is likely to change in the future, in response to human activities and natural factors. This page discusses the first two decadal cycles of NAWQA research from 1991 through 2012.

Date published: February 26, 2019
Status: Active

Flood Inundation Map (FIM) Libraries

The Flood Inundation Mapping Program focuses on developing flood inundation map libraries and helping communities pair those libraries with real-time stream data and National Weather Service flood forecasts to form a two-dimensional flood warning system. Together, these products can help communities estimate the extent of a flood and identify at-risk areas and resources in advance of...

Attribution: Water Resources