Water Resources

Filter Total Items: 359
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
Date published: February 27, 2019
Status: Active

Linking Selenium Sources to Ecosystems: Mining

Environmental sources of selenium (Se) such as from organic-enriched sedimentary deposits are geologic in nature and thus can occur on regional scales. A constructed map of the global distribution of Se source rocks informs potential areas of reconnaissance for modeling of Se risk including the phosphate deposits of southeastern Idaho and the coals of Appalachia.

Contacts: Theresa Presser, Joseph P. Skorupa
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 27, 2019
Status: Active

Linking Selenium Sources to Ecosystems: Modeling

Selenium (Se) as a contaminant of ecosystems is bioaccumulative and causes reproductive effects in fish and wildlife. Ecosystem-scale Se modeling predicts Se bioaccumulation based on dietary biodynamics within site-specific food webs. The model can be used to forecast Se toxicity under different management or regulatory proposals or to translate a tissue guideline to a dissolved guideline. ...

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

Water-Use Terminology

The following terms have been used in one or more of the water-use publications. The ...

Date published: February 27, 2019
Status: Completed

Hurricane Florence

Hurricane Florence was a long-lived Category 4 hurricane that impacted Cape Verde, the Bahamas, and the southeastern U.S. Hurricane Florence caused substantial flooding in North and South Carolina, primarily from freshwater flooding.

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

Hurricane Nate

Hurricane Nate affected Central America and the U.S. Gulf Coast from Oct. 4-11, 2017, making U.S. landfall near the mouth of the Mississippi River in Louisiana.

Date published: February 27, 2019
Status: Completed

Hurricane Maria

Hurricane Maria had devastating effects on the Carribean region including Puerto Rico, which took a direct hit as the Category Four hurricane crossed the entire island on Sept. 20, 2017.