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 is currently in its third decade-Cycle 3. The science strategy for Cycle 3 is based on evaluation of progress by NAWQA and its partners during Cycles 1 and 2 (1991-2012) and an analysis of stakeholder priorities. Specifically, input on key water issues and science needs has been solicited, reviewed, and supported by the National Research Council and more than 50 internal and external stakeholders who provided input between 2008-10. Nationally, the science strategy for Cycle 3 includes four common goals:
- Monitor surface-water and groundwater quality at multiple scales.
- Link the nature and distribution of water-quality conditions, as well as changes and trends in water-quality and aquatic ecosystems, to the human and natural factors that influence water quality and aquatic ecosystems.
- Evaluate relations between important water-quality and hydrologic stressors that cause degradation of stream ecosystems; findings will be incorporated into regional ecological models that examine the interdependent effects of multiple stressors.
- Evaluate the effects of management practices and future land use on stream ecosystems.
NEBRASKA WATER SCIENCE CENTER NAWQA STUDIES
Surface Water Status and Trends
The Nebraska Water Science Center (NEWSC) currently collects water samples from four surface-water sites in Nebraska. These four sites are sampled year round, but sampling is more frequent during the agricultural growing season (April through August):
- Dismal River near Thedford
- Maple Creek near Nickerson
- Elkhorn River near Waterloo
- Platte River at Louisville
One of the sites is considered a reference site (Dismal River near Thedford) because the watershed is relatively undisturbed. Constituents collected at these sites include nutrients, major ions, trace metals, carbon, and pesticides. Field parameters (water temperature, pH, specific conductance, alkalinity and dissolved oxygen) are measured in conjunction with each sample.
See how water-quality of the Nation's River and Streams has changed over time
Agriculture and Land Use Study
Thirty monitoring wells in the shallow glacial aquifers of eastern Nebraska were sampled to evaluate the amount of agricultural chemicals.
Regional Stream Quality Assessment
The Regional Stream Quality Assessment (RSQA) goals are to characterize multiple water-quality factors that are stressors to aquatic life ‐ contaminants, nutrients, sediment, and streamflow alteration – and to develop a better understanding of the relation of these stressors to ecological conditions in streams throughout the region. The Regional Stream Quality Assessment (RSQA) focused on a different region of the U.S. each year—the Midwest (2013), the Southeast (2014), the Pacific Northwest (2015), the Northeast (2016), and California (2017). Eight sites in Nebraska were sampled as part of the Midwest Stream Quality Assessment.
Midwest Stream Quality Assessment
Thirty-two public-supply wells, screened in the deeper portions of the High Plains aquifer, were sampled to evaluate the quality of public drinking water supply. Samples were analyzed for a large suite of regulated and unregulated constituents.
Learn more about the Principal Aquifer Survey: USGS Fact Sheet 2014-3024
Vertical Flow Path study
Fifteen moderate-depth domestic wells and 15 shallow-depth monitoring wells, screened in shallow quaternary aquifers within the High Plains aquifer in eastern Nebraska, were sampled to evaluate age-related trends of constituents across different land uses.
Agricultural Chemicals: Sources, Transport, and Fate
NAWQA assessed the sources, transport, and fate of chemicals applied to crops in agricultural basins across the Nation. Chemicals selected for study include nutrients (nitrogen and phosphorus) and about 50 commonly used pesticides and their transformation products, including triazine and acetanilide herbicides such as atrazine and metolachlor, and organophosphorus insecticides such as chlorpyrifos and diazinon.
Maple Creek, in Nebraska, respresents nationally important agricultural settings (chemical use, crops, and agricultural management practices) and natural settings (climate, geology, topography, and soils). Maple Creek, which is part of the Elkhorn River watershed, is representative of corn and soybean row cropping in the upper Great Plains. Water-quality samples were collected in the Maple Creek watershed from 2003 to 2005.
Effects of Nutrient Enrichment on Stream Ecosystems
This study determined how biological communities and processes respond to varying levels of nutrient enrichment among agricultural streams from contrasting environmental settings. Data for assessments of water quality, algae, invertebrates, and physical habitat were collected at 28 Nebraska streams during summer 2003. At each sampling site, water-quality, invertebrate and algal community structure and physical habitat parameters were assessed. At a subset of 20 sites measurements of specific conductance, pH, water temperature, and dissolved oxygen were collected at 5- to 15-minute intervals for a 48-hour period to allow the calculation of stream metabolism.
A NAWQA study of mercury contamination in streams across the U.S. was designed to describe the occurrence of total mercury and methylmercury in water and sediment, and total mercury in fish. Sampling sites were selected to represent the large national range of mercury deposition, and across the ranges of the transport and methylation of mercury in differing aquatic ecosystems. Samples of fish fillets, water, and bed sediments were collected at eight sites in Nebraska during low-flow conditions in July 2002. Widely available predacious fish species, of approximately 3 to 4 years of age, were targeted for sampling. Channel catfish were sampled at five Nebraska sites, and black crappie, creek chub, and largemouth bass were sampled at one site each. Laboratories determined mercury concentrations in the water, sediment, and tissue, and will verify fish-specimen age.
Transport of Anthropogenic and Natural Contaminants to Supply Wells Study
As part of NAWQA, a study was conducted from 2001 to 2011 to shed light on factors that affect the vulnerability of water from public-supply wells to contamination. The study was designed as a follow-up to earlier NAWQA studies that found mixtures of contaminants at low concentrations in groundwater near the water table in urban areas across the Nation and, less frequently, in deeper groundwater typically used for public supply.
Select publications from NAWQA studies in Nebraska are listed below.
Complete list of NAWQA publications for Nebraska :: All NAWQA publications
Water Quality in the High Plains Aquifer, Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming, 1999-2004
Trends in concentrations and use of agricultural herbicides for Corn Belt rivers, 1996-2006
Hydrogeology, Chemical Characteristics, and Transport Processes in the Zone of Contribution of a Public-Supply Well in York, Nebraska
Assessing the vulnerability of public-supply wells to contamination—High Plains Aquifer near York, Nebraska
Simulations of Ground-Water Flow, Transport, Age, and Particle Tracking near York, Nebraska, for a Study of Transport of Anthropogenic and Natural Contaminants (TANC) to Public-Supply Wells
Pesticides in rain in four agricultural watersheds in the United States
Occurrence and fate of pesticides in four contrasting agricultural settings in the United States
Riparian Land Use/Land Cover Data for Five Study Units in the Nutrient Enrichment Effects Topical Study of the National Water-Quality Assessment Program
Nutrient and Suspended-Sediment Trends in the Missouri River Basin, 1993-2003
Occurrence of Agricultural Chemicals in Shallow Ground Water and the Unsaturated Zone, Northeast Nebraska Glacial Till, 2002-04
Environmental setting of Maple Creek watershed, Nebraska
Water-quality assessment of the central Nebraska basins — Entering a new decade
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 is currently in its third decade-Cycle 3. The science strategy for Cycle 3 is based on evaluation of progress by NAWQA and its partners during Cycles 1 and 2 (1991-2012) and an analysis of stakeholder priorities. Specifically, input on key water issues and science needs has been solicited, reviewed, and supported by the National Research Council and more than 50 internal and external stakeholders who provided input between 2008-10. Nationally, the science strategy for Cycle 3 includes four common goals:
- Monitor surface-water and groundwater quality at multiple scales.
- Link the nature and distribution of water-quality conditions, as well as changes and trends in water-quality and aquatic ecosystems, to the human and natural factors that influence water quality and aquatic ecosystems.
- Evaluate relations between important water-quality and hydrologic stressors that cause degradation of stream ecosystems; findings will be incorporated into regional ecological models that examine the interdependent effects of multiple stressors.
- Evaluate the effects of management practices and future land use on stream ecosystems.
NEBRASKA WATER SCIENCE CENTER NAWQA STUDIES
Surface Water Status and Trends
The Nebraska Water Science Center (NEWSC) currently collects water samples from four surface-water sites in Nebraska. These four sites are sampled year round, but sampling is more frequent during the agricultural growing season (April through August):
- Dismal River near Thedford
- Maple Creek near Nickerson
- Elkhorn River near Waterloo
- Platte River at Louisville
One of the sites is considered a reference site (Dismal River near Thedford) because the watershed is relatively undisturbed. Constituents collected at these sites include nutrients, major ions, trace metals, carbon, and pesticides. Field parameters (water temperature, pH, specific conductance, alkalinity and dissolved oxygen) are measured in conjunction with each sample.
See how water-quality of the Nation's River and Streams has changed over time
Agriculture and Land Use Study
Thirty monitoring wells in the shallow glacial aquifers of eastern Nebraska were sampled to evaluate the amount of agricultural chemicals.
Regional Stream Quality Assessment
The Regional Stream Quality Assessment (RSQA) goals are to characterize multiple water-quality factors that are stressors to aquatic life ‐ contaminants, nutrients, sediment, and streamflow alteration – and to develop a better understanding of the relation of these stressors to ecological conditions in streams throughout the region. The Regional Stream Quality Assessment (RSQA) focused on a different region of the U.S. each year—the Midwest (2013), the Southeast (2014), the Pacific Northwest (2015), the Northeast (2016), and California (2017). Eight sites in Nebraska were sampled as part of the Midwest Stream Quality Assessment.
Midwest Stream Quality Assessment
Thirty-two public-supply wells, screened in the deeper portions of the High Plains aquifer, were sampled to evaluate the quality of public drinking water supply. Samples were analyzed for a large suite of regulated and unregulated constituents.
Learn more about the Principal Aquifer Survey: USGS Fact Sheet 2014-3024
Vertical Flow Path study
Fifteen moderate-depth domestic wells and 15 shallow-depth monitoring wells, screened in shallow quaternary aquifers within the High Plains aquifer in eastern Nebraska, were sampled to evaluate age-related trends of constituents across different land uses.
Agricultural Chemicals: Sources, Transport, and Fate
NAWQA assessed the sources, transport, and fate of chemicals applied to crops in agricultural basins across the Nation. Chemicals selected for study include nutrients (nitrogen and phosphorus) and about 50 commonly used pesticides and their transformation products, including triazine and acetanilide herbicides such as atrazine and metolachlor, and organophosphorus insecticides such as chlorpyrifos and diazinon.
Maple Creek, in Nebraska, respresents nationally important agricultural settings (chemical use, crops, and agricultural management practices) and natural settings (climate, geology, topography, and soils). Maple Creek, which is part of the Elkhorn River watershed, is representative of corn and soybean row cropping in the upper Great Plains. Water-quality samples were collected in the Maple Creek watershed from 2003 to 2005.
Effects of Nutrient Enrichment on Stream Ecosystems
This study determined how biological communities and processes respond to varying levels of nutrient enrichment among agricultural streams from contrasting environmental settings. Data for assessments of water quality, algae, invertebrates, and physical habitat were collected at 28 Nebraska streams during summer 2003. At each sampling site, water-quality, invertebrate and algal community structure and physical habitat parameters were assessed. At a subset of 20 sites measurements of specific conductance, pH, water temperature, and dissolved oxygen were collected at 5- to 15-minute intervals for a 48-hour period to allow the calculation of stream metabolism.
A NAWQA study of mercury contamination in streams across the U.S. was designed to describe the occurrence of total mercury and methylmercury in water and sediment, and total mercury in fish. Sampling sites were selected to represent the large national range of mercury deposition, and across the ranges of the transport and methylation of mercury in differing aquatic ecosystems. Samples of fish fillets, water, and bed sediments were collected at eight sites in Nebraska during low-flow conditions in July 2002. Widely available predacious fish species, of approximately 3 to 4 years of age, were targeted for sampling. Channel catfish were sampled at five Nebraska sites, and black crappie, creek chub, and largemouth bass were sampled at one site each. Laboratories determined mercury concentrations in the water, sediment, and tissue, and will verify fish-specimen age.
Transport of Anthropogenic and Natural Contaminants to Supply Wells Study
As part of NAWQA, a study was conducted from 2001 to 2011 to shed light on factors that affect the vulnerability of water from public-supply wells to contamination. The study was designed as a follow-up to earlier NAWQA studies that found mixtures of contaminants at low concentrations in groundwater near the water table in urban areas across the Nation and, less frequently, in deeper groundwater typically used for public supply.
Select publications from NAWQA studies in Nebraska are listed below.
Complete list of NAWQA publications for Nebraska :: All NAWQA publications