National Water Quality Program


The National Water Quality Program provides an understanding of water-quality conditions; whether conditions are getting better or worse over time; and how natural features and human activities affect those conditions.

More about this program

Featured Study: Flow Modification of the Nation's Streams

Featured Study: Flow Modification of the Nation

A new USGS study reports that human management of land and water resources have modified natural patterns of streamflow along more than 1.2 million miles of U.S. streams. Flow modification was associated with losses of native fish or invertebrates.

Learn more

Featured Study: Fluoride in Groundwater Used for Drinking

Featured Study: Fluoride in Groundwater Used for Drinking

Fluoride occurs commonly in groundwater used for drinking, but typically at concentrations less than the drinking-water standard for human health, reports a new study, and in many cases below the optimal concentration to prevent tooth decay.

Learn More


Date published: September 16, 2020

New Study Identifies Pesticide Mixtures in U.S. Rivers and Streams

A mix of multiple pesticides is common in many U.S. streams, reports a new study by the U.S. Geological Survey National Water Quality Program.

Date published: September 4, 2020

New USGS website provides water quality information for U.S. streams and rivers

Interested in water-quality concentrations, loads, and trends in streams and rivers across the United States? Check out a new USGS website with data from the USGS National Water Quality Network—110 stream and river sites with long-term, consistent data on water quality.

Date published: June 24, 2020

Pavement is contributing sediment to urban streams

Dirt, sand, and other particulate material on parking lots and streets is washing off into urban streams, reports a new study by the U.S. Geological Survey Regional Stream Quality Assessment. The study used novel particle tracers to determine that particles washed from pavement made up...


Publication Thumbnail
Year Published: 2019

Hydrocarbons in upland groundwater, Marcellus Shale Region, Northeastern Pennsylvania and Southern New York, USA

Water samples from 50 domestic wells located <1 km (proximal) and >1 km (distal) from shale-gas wells in upland areas of the Marcellus Shale region were analyzed for chemical, isotopic, and groundwater-age tracers. Uplands were targeted because natural mixing with brine and hydrocarbons from deep formations is less common in those areas...

McMahon, Peter B.; Lindsey, Bruce D.; Conlon, Matthew D.; Hunt, Andrew G.; Belitz, Kenneth; Jurgens, Bryant; Varela, Brian

Publication Thumbnail
Year Published: 2019

Estimating domestic well locations and populations served in the contiguous U.S. for years 2000 and 2010

Domestic wells provide drinking water supply for approximately 40 million people in the United States. Knowing the location of these wells, and the populations they serve, is important for identifying heavily used aquifers, locations susceptible to contamination, and populations potentially impacted by poor-quality groundwater. The 1990 census was...

Johnson, Tyler D.; Belitz, Kenneth; Lombard, Melissa

Publication Thumbnail
Year Published: 2019

Assessing water-quality changes in U.S. rivers at multiple geographic scales using results from probabilistic and targeted monitoring

Two commonly used approaches for water quality monitoring are probabilistic and targeted. In a probabilistic approach like the US Environmental Protection Agency’s National Rivers and Streams Assessment, monitoring sites are selected using a statistically representative approach. In a targeted approach like that used by many monitoring...

Sprague, Lori A.; Mitchell, Richard M; Pollard, Amina I.; Falcone, James A.