Search USGS⌕ Search

USGS · 70180265

A national look at water quality

Abstract

Most water - quality problems we face today result from diffuse "nonpoint" sources of pollution from agricultural land, urban development, forest harvesting and the atmosphere (U.S. Army Corps of Engineers et al., 1999). It is difficult to quantify nonpoint sources because the contaminants they deliver vary in composition and concentrations from hour to hour and season to season. Moreover, the nature of the contamination is complex and varied. When Congress enacted the Clean Water Act 30 years ago, attention was focused on water - quality issues related to the sanitation of rivers and streams - bacteria counts, oxygen in the water for fish, nutrients, temperature, and salinity. Now, attention is turning to the hundreds of synthetic organic compounds like pesticides used in agricultural and residential areas, volatile organics in solvents and gasoline, microbial and viral contamination, and pharmaceuticals and hormones.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Robert J. Gilliom, David K. Mueller, John S. Zogorski, Sarah J. Ryker. 2002. A national look at water quality. https://pubs.usgs.gov/publication/70180265

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

Contaminants of emerging concern in the environment: Where we have been and what does the future hold?

In 1962, Rachel Carson’s book Silent Spring alerted the nation to the dangers of manmade chemicals and indiscriminate use of pesticides. DDT was the culprit and its use threatened a variety of wildlife, including the national bird, bald eagles. In 1969, pressured by scientists and the public, the United States banned almost all uses of DDT; however, DDT was just the tip of the chemical iceberg. In 1996, Theo Colborn’s book, Our Stolen Future, again alerted the public to the dangers of chemical exposure. Endocrine-disrupting chemicals were identified as concerns because exposure to extremely small concentrations can have adverse effects on people and wildlife by interfering with chemical messaging systems, affecting things like sexual development and reproduction.

Water Resources Impact↗

Biota: Providing often-overlooked connections among freshwater systems

When we think about connections in and among aquatic systems, we typically envision clear headwater streams flowing into downstream rivers, river floodwaters spilling out onto adjacent floodplains, or groundwater connecting wetlands to lakes and streams. However, there is another layer of connectivity moving materials among freshwater systems, one with connections that are not always tied to downgradient flows of surface waters and groundwater. These movements are those of organisms, key components of virtually every freshwater system on the planet. In their movements across the landscape, biota connect aquatic systems in often-overlooked ways.

Water Resources Impact↗

The Open Water Data Initiative: Water information for a thirsty nation

Initial efforts of the Open Water Data Initiative have focused on three use cases covering flooding, drought, and contaminant spill response, with a goal of identifying critical water data resources and making them more accessible. Significant progress has been made in the past year, although much remains to be done.

Water Resources Impact↗