Surface-Water Quality and Ecology

Featured: Nutrient yields in the Mississippi/Atchafalaya River Basin

Featured: Nutrient yields in the Mississippi/Atchafalaya River Basin

new USGS study estimates total nitrogen (N) and total phosphorus (P) yields from catchments throughout the Mississippi/Atchafalaya River Basin, which drains about 41% of the conterminous U.S. Results could assist nutrient reduction strategies.

Learn more

Featured: Chemical Mixtures in Small U.S. Streams

Featured: Chemical Mixtures in Small U.S. Streams

Mixtures of organic chemicals are ubiquitous in small U.S. streams, reports a new study by the U.S. Geological Survey. In many streams the mixtures could be affecting stream organisms.

Learn More

Science Center Objects

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.

The Nation's rivers and streams are a priceless resource—they provide drinking water for a growing population, irrigation for crops, habitat for aquatic life, and countless recreational opportunities.

NAWQA research on surface-water quality is focusing on three areas:

Explore NAWQA science on topics related to water quality in streams and rivers

Relations between land use and surface-water quality 



Contaminants in surface water



   Emerging contaminants (pharmaceuticals, personal-care products, and more)

   Sediment-associated contaminants (metals, pesticides, PAHs, and more)

   Polycyclic aromatic hydrocarbons (PAHs)


Relations to aquatic life

   Stream ecology

   Mercury in stream ecosystems

   Flow alteration

   Harmful algal blooms (HABs)

Drinking water issues

   Drinking and source water

   Chloride and salinity


   Water-quality benchmarks

Trends in water quality

   Water-quality trends from lake sediment cores

   Water-quality trends


How do we do it?  

Access USGS publications and manuals on sample-collection methods.


Looking for information on groundwater quality as well?  

Explore these links:


   Surface-water/groundwater interaction