The USGS National Water-Quality Assessment Project (NAWQA) is now part of the USGS National Water-Quality Program (NWQP). NAWQA provides nationally consistent data and information on the quality of the Nation’s water. Studies provide information on current water-quality conditions, a baseline for trend evaluation, and an understanding of what factors affect water quality. Groundwater studies for the NAWQA program provide information on the quality of water in shallow monitoring wells, domestic-supply wells, and public-supply wells. The data collected from surface water samples will be used in a national context to describe water quality characteristics of rivers and streams influenced by various land uses (urban, agricultural, and reference).
In 1991, Congress established the National Water-Quality Assessment (NAWQA) 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. Since then, NAWQA has been a leading source of scientific data and knowledge used by national, regional, state, and local agencies to develop science-based policies and management strategies to improve and protect water resources used for drinking water, recreation, irrigation, energy development, and ecosystem needs.
NAWQA studies have been conducted during decadal cycles:
- Cycle I: 1991-2001
- Cycle II: 2002-2012
- Cycle III: 2013-2023
NAWQA Cycle 3 has the followig science goals:
- Goal 1 –Assess the current quality of the Nation’s freshwater resources and how water quality is changing over time (Status and Trends)
- Goal 2 – Continuing: Evaluate how human activities and natural factors, such as land use and climate change, are affecting the quality of surface water and groundwater (Understanding Causes)
- Goal 3 –Determine the effects of contaminants, excess nutrients, sediment, and streamflow alteration on aquatic ecosystems (Understanding Effects)
- Goal 4 –Predict the effects of human activities, climate change, and management strategies on water quality and ecosystem condition (Forecasting)
Groundwater Studies
NAWQA studies include Land Use Studies (LUS), Major Aquifer Studies (MAS), and Principal Aquifer Studies (PAS). These three study types are based on sampling networks of wells distributed across an area of interest.
- LUS networks typically consist of observation wells that are relatively shallow;
- MAS networks typically consist of domestic-supply wells that are intermediate in depth; and
- PAS networks typically consist of public-supply wells that are relatively deep.
As part of NAWQA Cycle III, USGS scientists collect and record both water levels and water quality data on local groundwater through well networks and collect samples within LUS, MAS, and PAS network within the Basin and Range.
The Decadal Change in Groundwater Quality web-mapping application shows how concentrations of pesticides, nutrients, metals, and organic contaminants in groundwater are changing during decadal periods across the Nation:
Visit the Decadal Change in Groundwater Quality web site
Surface-Water Studies
NAWQA characterizes the status and trends of water quality and aquatic ecosystems by monitoring ambient water-quality and ecological conditions through the newly established National Water Quality Network (NWQN) for Rivers and Streams. The NWQN is the primary source of data for the systematic annual reporting of ambient conditions nationally. The new NWQN includes 22 large river coastal sites, 41 large river inland sites, 30 wadeable stream reference sites, 10 wadeable stream urban sites, and 10 wadeable stream agricultural sites.
One NWQN site currently is monitored in Nevada:
Truckee River Near Tracy (USGS Site ID 10350340)
Samples are collected from this site 18 times per year and analyzed for
- Nutrients (nitrogen and phosphorus species)
- Chloride and sulfate
- Turbidity
- Dissolved organic carbon, Dissolved inorganic carbon, UV-absorbing constituents
- Selected trace elements (arsenic, lithium, selenium, and vanadium)
- Suspended sediment
- Pesticides
An annual summary of water-quality data from Nevada's NWQN is available from the USGS Water Quality Tracking web site:
- Overview
The USGS National Water-Quality Assessment Project (NAWQA) is now part of the USGS National Water-Quality Program (NWQP). NAWQA provides nationally consistent data and information on the quality of the Nation’s water. Studies provide information on current water-quality conditions, a baseline for trend evaluation, and an understanding of what factors affect water quality. Groundwater studies for the NAWQA program provide information on the quality of water in shallow monitoring wells, domestic-supply wells, and public-supply wells. The data collected from surface water samples will be used in a national context to describe water quality characteristics of rivers and streams influenced by various land uses (urban, agricultural, and reference).
Sources/Usage: Public Domain.Map of the Nevada NAWQA study units. (Public domain.) In 1991, Congress established the National Water-Quality Assessment (NAWQA) 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. Since then, NAWQA has been a leading source of scientific data and knowledge used by national, regional, state, and local agencies to develop science-based policies and management strategies to improve and protect water resources used for drinking water, recreation, irrigation, energy development, and ecosystem needs.
NAWQA studies have been conducted during decadal cycles:
Sources/Usage: Public Domain.Map of the Nevada Basin and Range NAWQA study unit showing land use. (Public domain.) - Cycle I: 1991-2001
- Cycle II: 2002-2012
- Cycle III: 2013-2023
NAWQA Cycle 3 has the followig science goals:
- Goal 1 –Assess the current quality of the Nation’s freshwater resources and how water quality is changing over time (Status and Trends)
- Goal 2 – Continuing: Evaluate how human activities and natural factors, such as land use and climate change, are affecting the quality of surface water and groundwater (Understanding Causes)
- Goal 3 –Determine the effects of contaminants, excess nutrients, sediment, and streamflow alteration on aquatic ecosystems (Understanding Effects)
- Goal 4 –Predict the effects of human activities, climate change, and management strategies on water quality and ecosystem condition (Forecasting)
Groundwater Studies
Sources/Usage: Public Domain.USGS scientist Dan Riddle processing water-quality samples from a well in Nevada. (Public domain.) NAWQA studies include Land Use Studies (LUS), Major Aquifer Studies (MAS), and Principal Aquifer Studies (PAS). These three study types are based on sampling networks of wells distributed across an area of interest.
- LUS networks typically consist of observation wells that are relatively shallow;
- MAS networks typically consist of domestic-supply wells that are intermediate in depth; and
- PAS networks typically consist of public-supply wells that are relatively deep.
As part of NAWQA Cycle III, USGS scientists collect and record both water levels and water quality data on local groundwater through well networks and collect samples within LUS, MAS, and PAS network within the Basin and Range.
The Decadal Change in Groundwater Quality web-mapping application shows how concentrations of pesticides, nutrients, metals, and organic contaminants in groundwater are changing during decadal periods across the Nation:
Visit the Decadal Change in Groundwater Quality web site
Surface-Water Studies
Sources/Usage: Public Domain.Collecting water-quality samples using a crane from a bridge on the Truckee River near Tracy, Nevada. (Public domain.) NAWQA characterizes the status and trends of water quality and aquatic ecosystems by monitoring ambient water-quality and ecological conditions through the newly established National Water Quality Network (NWQN) for Rivers and Streams. The NWQN is the primary source of data for the systematic annual reporting of ambient conditions nationally. The new NWQN includes 22 large river coastal sites, 41 large river inland sites, 30 wadeable stream reference sites, 10 wadeable stream urban sites, and 10 wadeable stream agricultural sites.
One NWQN site currently is monitored in Nevada:
Truckee River Near Tracy (USGS Site ID 10350340)
Samples are collected from this site 18 times per year and analyzed for
- Nutrients (nitrogen and phosphorus species)
- Chloride and sulfate
- Turbidity
- Dissolved organic carbon, Dissolved inorganic carbon, UV-absorbing constituents
- Selected trace elements (arsenic, lithium, selenium, and vanadium)
- Suspended sediment
- Pesticides
An annual summary of water-quality data from Nevada's NWQN is available from the USGS Water Quality Tracking web site:
- Publications