Every day, millions of gallons of groundwater are pumped to supply drinking water for about 140 million people, almost one-half of the Nation’s population. Learn about the quality and availability of groundwater for drinking, where and why groundwater quality is degraded, and where groundwater quality is changing.
Featured: 3-D Models of As and Mn in the Glacial Aquifer System
New 3-D models from the USGS National Water Quality Program predict where high concentrations of arsenic and manganese likely occur in the glacial aquifer system, groundwater supply for 30 million. Redox conditions and pH are controlling factors.
Featured: Updated Information on Groundwater Quality
Three new USGS fact sheets update information on groundwater quality in the nation's most heavily used aquifers. Fact sheets are now available for the Edwards-Trinity aquifer system, the Stream Valley aquifers, and the Colorado Plateau aquifers.
Groundwater is our invisible, vital resource. The USGS National Water Quality Program (NWQP) is focusing on studies of principal aquifers, regionally extensive aquifers that are critical sources of groundwater used for public supply. The studies have two main thrusts:
- Current conditions and changes through time. These assessments characterize groundwater quality in principal aquifers, comparing concentrations of inorganic constituents, such as arsenic and nitrate, and organic constituents, such as pesticides and volatile organic compounds, to benchmarks established for the protection of human health. Tracking changes in groundwater quality through time and investigating the reasons for these changes is crucial for informing management decisions to protect and sustain our valuable groundwater resources. See how concentrations of metals, nutrients, pesticides, and organic contaminants in groundwater are changing during decadal periods across the Nation, and view real-time fluctuations in groundwater quality.
- Predicting groundwater quality. Statistical models and 3-D characterizations predict where a contaminant is likely to occur in groundwater, at what depth, and at what concentration. These forecasts anticipate water quality in areas where groundwater has not been sampled.
From 1991 to 2010, about 6,600 wells were sampled by the NWQP to document where contaminants occur and to develop an understanding of the natural and human factors that affect the occurrence of contaminants in the Nation’s groundwater. Learn about groundwater quality in the Nation’s principal aquifers, 1991–2010.
Explore USGS science on topics related to groundwater quality:
National Water Quality Assessment (NAWQA) Project
Contaminants in groundwater
Arsenic and Drinking Water
Chloride, Salinity, and Dissolved Solids
Emerging Contaminants
Metals and Other Trace Elements
Nutrients and Eutrophication
Pesticides and Water Quality
Radionuclides
Volatile organic compounds (VOCs)
Hydraulic Fracturing
Drinking and source-water quality
Corrosivity
Domestic (private) supply wells
Public-supply wells
Drinking-water taste and odor
Water-Quality Benchmarks for Contaminants
Processes affecting groundwater quality
Groundwater Age
Oxidation/Reduction (Redox)
How do we do it? Access USGS publications and manuals on National Water-Quality Project sampling methods.
Looking for information on surface-water quality as well? Explore these links:
Surface-Water Quality and Ecology
Groundwater/Surface-Water Interaction
National Water-Quality Assessment (NAWQA)
Nutrients and Eutrophication
Drinking Water and Source Water Research
Groundwater/Surface-Water Interaction
Hydraulic Fracturing
Chloride, Salinity, and Dissolved Solids
Arsenic and Drinking Water
Pesticides and Water Quality
Metals and Other Trace Elements
Corrosivity
Public Supply Wells
Domestic (Private) Supply Wells
Contaminants present in many parts of the Glacial aquifer system
Are you one of 30 million Americans whose drinking-water supply relies on groundwater from the glacial aquifer system? A new USGS study assesses the quality of untreated groundwater from this critical water resource, which underlies parts of 25 northern U.S. states.
- Overview
Every day, millions of gallons of groundwater are pumped to supply drinking water for about 140 million people, almost one-half of the Nation’s population. Learn about the quality and availability of groundwater for drinking, where and why groundwater quality is degraded, and where groundwater quality is changing.
Featured: 3-D Models of As and Mn in the Glacial Aquifer System
New 3-D models from the USGS National Water Quality Program predict where high concentrations of arsenic and manganese likely occur in the glacial aquifer system, groundwater supply for 30 million. Redox conditions and pH are controlling factors.
Featured: Updated Information on Groundwater Quality
Three new USGS fact sheets update information on groundwater quality in the nation's most heavily used aquifers. Fact sheets are now available for the Edwards-Trinity aquifer system, the Stream Valley aquifers, and the Colorado Plateau aquifers.
Groundwater is our invisible, vital resource. The USGS National Water Quality Program (NWQP) is focusing on studies of principal aquifers, regionally extensive aquifers that are critical sources of groundwater used for public supply. The studies have two main thrusts:
Sources/Usage: Public Domain.Collecting groundwater data - Current conditions and changes through time. These assessments characterize groundwater quality in principal aquifers, comparing concentrations of inorganic constituents, such as arsenic and nitrate, and organic constituents, such as pesticides and volatile organic compounds, to benchmarks established for the protection of human health. Tracking changes in groundwater quality through time and investigating the reasons for these changes is crucial for informing management decisions to protect and sustain our valuable groundwater resources. See how concentrations of metals, nutrients, pesticides, and organic contaminants in groundwater are changing during decadal periods across the Nation, and view real-time fluctuations in groundwater quality.
- Predicting groundwater quality. Statistical models and 3-D characterizations predict where a contaminant is likely to occur in groundwater, at what depth, and at what concentration. These forecasts anticipate water quality in areas where groundwater has not been sampled.
From 1991 to 2010, about 6,600 wells were sampled by the NWQP to document where contaminants occur and to develop an understanding of the natural and human factors that affect the occurrence of contaminants in the Nation’s groundwater. Learn about groundwater quality in the Nation’s principal aquifers, 1991–2010.
Explore USGS science on topics related to groundwater quality:
National Water Quality Assessment (NAWQA) Project
Contaminants in groundwater
Arsenic and Drinking Water
Chloride, Salinity, and Dissolved Solids
Emerging Contaminants
Metals and Other Trace Elements
Nutrients and Eutrophication
Pesticides and Water Quality
Radionuclides
Volatile organic compounds (VOCs)
Hydraulic FracturingDrinking and source-water quality
Corrosivity
Domestic (private) supply wells
Public-supply wells
Drinking-water taste and odor
Water-Quality Benchmarks for ContaminantsProcesses affecting groundwater quality
Groundwater Age
Oxidation/Reduction (Redox)How do we do it? Access USGS publications and manuals on National Water-Quality Project sampling methods.
Looking for information on surface-water quality as well? Explore these links:
Surface-Water Quality and Ecology
Groundwater/Surface-Water Interaction
- Science
Filter Total Items: 20
National Water-Quality Assessment (NAWQA)
Our surface water, groundwater, and aquatic ecosystems are priceless resources, used by people across the Nation for drinking, irrigation, industry, and recreation. The National Water-Quality Assessment (NAWQA) Project is a leading source of scientific data and knowledge for development of science-based policies and management strategies to improve and protect our water resources.Nutrients and Eutrophication
Like people, plants need nutrients, but too much of a good thing can be a problem. Nutrients, such as nitrogen and phosphorus, occur naturally, but most of the nutrients in our waterways come from human activities and sources—fertilizers, wastewater, automobile exhaust, animal waste. The USGS investigates the source, transport, and fate of nutrients and their impacts on the world around us.Drinking Water and Source Water Research
Reliable drinking water is vital for the health and safety of all Americans. The USGS monitors and assesses the quality of the water used as a source for our nation's drinking water needs.Groundwater/Surface-Water Interaction
Water and the chemicals it contains are constantly being exchanged between the land surface and the subsurface. Surface water seeps into the ground and recharges the underlying aquifer—groundwater discharges to the surface and supplies the stream with baseflow. USGS Integrated Watershed Studies assess these exchanges and their effect on surface-water and groundwater quality and quantity.Hydraulic Fracturing
Hydraulic fracturing, commonly known as fracking, is the process of injecting water, sand, and/or chemicals into a well to break up underground bedrock to free up oil or gas reserves. The USGS monitors the environmental impact of this practice across the country, from potential earthquakes to degraded groundwater quality.Chloride, Salinity, and Dissolved Solids
All natural waters contain some dissolved solids (salinity) from contact with soils, rocks, and other natural materials. Too much, though, and dissolved solids can impair water use. Unpleasant taste, high water-treatment costs, mineral accumulation in plumbing, staining, corrosion, and restricted use for irrigation are among the problems associated with elevated concentrations of dissolved solids.Arsenic and Drinking Water
Arsenic is a naturally occurring element, but long-term exposure can cause cancer in people. There has been a substantial amount of research done to address arsenic in groundwater and drinking-water supplies around the country. The USGS studies local and national sources of arsenic to help health officials better manage our water resources.Pesticides and Water Quality
Pesticides are chemicals designed to kill pests, including insects (insecticides), weeds (herbicides), and fungi (fungicides). The USGS assesses the occurrence and behavior of pesticides in streams, lakes, and groundwater and the potential for pesticides to contaminate our drinking-water supplies or harm aquatic ecosystems.Metals and Other Trace Elements
Metals, metalloids, and radionuclides all are trace elements that occur naturally in the Earth's crust. In small quantities many trace elements are essential for health in all living organisms, but some trace elements can be toxic or cause cancer, and some can bioaccumulate. The USGS investigates where and how trace elements make their way into our Nation's surface water and groundwater.Corrosivity
Corrosivity describes how aggressive water is at corroding pipes and fixtures. Corrosive water can cause lead and copper in pipes to leach into drinking water and can eventually cause leaks in plumbing. Surface water and groundwater, both sources of drinking water, can potentially be corrosive.Public Supply Wells
Are you among the more than 100 million people in the U.S. who relies on a public-supply well for your drinking water? Although the quality of finished drinking water from public water systems is regulated by the EPA, long-term protection and management of the raw groundwater tapped by public-supply wells requires an understanding of the occurrence of contaminants in this invisible, vital resource...Domestic (Private) Supply Wells
More than 43 million people—about 15 percent of the U.S. population—rely on domestic (private) wells as their source of drinking water. The quality and safety of water from domestic wells are not regulated by the Federal Safe Drinking Water Act or, in most cases, by state laws. Instead, individual homeowners are responsible for maintaining their domestic well systems and for monitoring water... - Data
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Contaminants present in many parts of the Glacial aquifer system
Are you one of 30 million Americans whose drinking-water supply relies on groundwater from the glacial aquifer system? A new USGS study assesses the quality of untreated groundwater from this critical water resource, which underlies parts of 25 northern U.S. states.