Melissa Riskin
Melissa Riskin is a Hydrologist and Coordinator of the National Water Quality Network (NWQN).
Professional Experience
2023-present, National Water Quality Network (NWQN) Coordinator. Coordinates the sampling of 105 stream and river sites with long-term, consistent information on streamflow and water-quality conditions. Product owner of Superfly Field Software.
2019-2022, National Water Quality Network Assistant Coordinator, Assist in coordination of the USGS National Water Quality Network (NWQN) that consists of 110 stream and river sites with long-term, consistent information on streamflow and water-quality conditions. Product owner of Superfly Field Software.
2014-2019, NAWQA Status and Trends Team, National Water Quality Program. Project Lead for the National Water Quality Trends update. Harmonizing over 112 million records retrieved from the Water Quality Portal for use in the national surface-water trends report and mapper update.
2012-2014, NAWQA Data Aggregation Team, National Water Quality Program. Compilation, validation and formatting of large water-quality data sets for inclusion in the national database.
2003-2015, Hydrologist 1) Surface water-quality and ecology sampling lead for NAWQA Project 2) Canadian River Study to compare streamflow for various climate change scenarios 3) Hydrologic Total Maximum Daily Load Study to address aquatic life impairment 4) Field coordinator to evaluate effects of potential changes in streamflow regime on aquatic-invertebrates
2000-2002, Hydrologist, New Hampshire-Vermont WSC. Surface-water and ecological sampling; Investigated relation between nutrient and chlorophyll a concentrations in New England Streams; Responsible for the deployment and maintenance of sondes with a special focus on the YSI chlorophyll a sensor.
1998-2000, Hydrologist, New Jersey WSC. Collection and processing of surface-water and ground-water quality samples as part of the NJ Ambient Monitoring Network using USGS protocols.
Education and Certifications
M.S. in Hydrology, University of New Hampshire, 2002
B.S. in Earth Science (Minor in Geology), Pennsylvania State University, 1997
Science and Products
Concentrations of 6PPD and 6PPD-Quinone in a United States reconnaissance of stormwater, surface water, and groundwater, 2018-24
From 2018 to 2024 surface waters (fresh and brackish), groundwater, and stormwater (runoff, re-use) samples were collected from sites with varying landuse (agricultural, forested, and urban) and streamflow conditions and analyzed at the Organic Geochemistry Research Laboratory in Lawrence, Kansas for the tire antioxidant 6PPD (6-p-phenylenediamine; N-(1,3-Dimethylbutyl)-N’-phenyl-p...
Evaluation of preservation techniques for trace metals and major cations for surface waters collected from the U.S. Geological Survey's National Water Quality Network Sites
The USGS National Field Manual (NFM) states "A representative sample is one that typifies in time and space that part of the aqueous system to be studied" and "obtaining representative samples is of primary importance for a relevant description of the environment." The NFM contains detailed chapters on the best practices for representative and contamination free sampling of major and...
Water-quality and streamflow datasets used in Weighted Regressions on Time, Discharge, and Season (WRTDS) models to determine trends in the Nation’s rivers and streams, 1972-2017
In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project. One of the major goals of the NAWQA project was to determine how river water quality has changed over time. To support that goal, long-term consistent and comparable monitoring has been conducted by the USGS on...
Pesticide datasets from the National Water Quality Laboratory: a review of recent practices of censoring scenarios for select groundwater and surfacewater results, 2001-2015
This data release includes all pesticide results from selected batches of water samples analyzed by the U.S Geological Survey National Water Quality Laboratory (NWQL). Samples were analyzed using gas chromatography/mass spectrometry (GCMS) or liquid chromatography/mass spectrometry (LCMS) methods. Eight datasets are included in this data release; 1) all environmental and field quality...
Daily streamflow datasets used to analyze trends in streamflow at sites also analyzed for trends in water quality and ecological condition in the Nation's rivers and streams
In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring...
Ecological community datasets used to evaluate the presence of trends in ecological communities in selected rivers and streams across the United States, 1992-2012
In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality and ecological conditions change over time. To support that goal, long-term consistent and...
Pesticide concentration and streamflow datasets used to evaluate pesticide trends in the Nations rivers and streams, 1992-2012
In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring...
Filter Total Items: 17
The U.S. Geological Survey National Water Quality Network—Surface Water—2023
The U.S. Geological Survey (USGS) National Water Quality Network for surface water (NWQN-SW) was established in 2013 to develop long-term, comparable assessments of surface-water quality in support of national, regional, state, and local needs related to water-quality management and policy. Waterquality samples are collected at each site and measured for a variety of parameters. In 2023...
Authors
Melissa L. Riskin
USGS National Water Quality Monitoring Network
What is the U.S. Geological Survey National Water Quality Monitoring Network?Understanding the water quality of U.S. streams and rivers requires consistent data collection and analysis over decades. The U.S. Geological Survey’s (USGS) National Water Quality Network (NWQN) was established to facilitate national-scale understanding of surface-water quality conditions through the collection...
Authors
Melissa L. Riskin, Casey J. Lee
Landscape drivers of dynamic change in water quality of US rivers
Water security is a top concern for social well-being and dramatic changes in the availability of freshwater have occurred as a result of human uses and landscape management. Elevated nutrient loading and perturbations to major ion composition have resulted from human activities and have degraded freshwater resources. This study addresses the emerging nature of stream water quality in...
Authors
Edward G. Stets, Lori A. Sprague, Gretchen P. Oelsner, Henry M. Johnson, Jennifer C. Murphy, Karen R. Ryberg, Aldo V. Vecchia, Robert E. Zuellig, James A. Falcone, Melissa L. Riskin
Use of set blanks in reporting pesticide results at the U.S. Geological Survey National Water Quality Laboratory, 2001-15
Executive SummaryBackground.—Pesticide results from the U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL) are used for water-quality assessments by many agencies and organizations. The USGS is committed to providing data of the highest possible quality to the consumers of its data. A cooperator’s inquiries about specific pesticide detections in water revealed...
Authors
Laura Medalie, Mark W. Sandstrom, Patricia L. Toccalino, William T. Foreman, Rhiannon C. ReVello, Laura M. Bexfield, Melissa L. Riskin
Water-quality trends in U.S. rivers, 2002 to 2012: Relations to levels of concern
Effective management and protection of water resources relies upon understanding how water-quality conditions are changing over time. Water-quality trends for ammonia, chloride, nitrate, sulfate, total dissolved solids (TDS), total nitrogen (TN) and total phosphorus (TP) were assessed at 762 sites located in the conterminous United States between 2002 and 2012. Annual mean concentrations...
Authors
Megan E. Shoda, Lori A. Sprague, Jennifer C. Murphy, Melissa L. Riskin
Quality-control design for surface-water sampling in the National Water-Quality Network
The data-quality objectives for samples collected at surface-water sites in the National Water-Quality Network include estimating the extent to which contamination, matrix effects, and measurement variability affect interpretation of environmental conditions. Quality-control samples provide insight into how well the samples collected at surface-water sites represent the true...
Authors
Melissa L. Riskin, David C. Reutter, Jeffrey D. Martin, David K. Mueller
Water-quality trends in the nation’s rivers and streams, 1972–2012—Data preparation, statistical methods, and trend results
Since passage of the Clean Water Act in 1972, Federal, State, and local governments have invested billions of dollars to reduce pollution entering rivers and streams. To understand the return on these investments and to effectively manage and protect the Nation’s water resources in the future, we need to know how and why water quality has been changing over time. As part of the National...
Authors
Gretchen P. Oelsner, Lori A. Sprague, Jennifer C. Murphy, Robert E. Zuellig, Henry M. Johnson, Karen R. Ryberg, James A. Falcone, Edward G. Stets, Aldo V. Vecchia, Melissa L. Riskin, Laura A. De Cicco, Taylor J. Mills, William H. Farmer
Method to support Total Maximum Daily Load development using hydrologic alteration as a surrogate to address aquatic life impairment in New Jersey streams
More than 300 ambient monitoring sites in New Jersey have been identified by the New Jersey Department of Environmental Protection (NJDEP) in its integrated water-quality monitoring and assessment report (that is, the 305(b) Report on general water quality and 303(d) List of waters that do not support their designated uses) as being impaired with respect to aquatic life; however, no...
Authors
Jonathan Kennen, Melissa L. Riskin, Pamela A. Reilly, Susan J. Colarullo
Variable contributions of mercury from groundwater to a first-order urban coastal plain stream in New Jersey, USA
Filtered total mercury (FTHg) concentrations in a rapidly urbanizing area ranged from 50 to 250 ng/L in surface waters of the Squankum Branch, a tributary to a major river (Great Egg Harbor River (GEHR)) traversing both urban and forested/wetland areas in the Coastal Plain of New Jersey. An unsewered residential area with Hg-contaminated well water (one of many in the region) is adjacent...
Authors
Julia Barringer, Zoltan Szabo, Pamela A. Reilly, Melissa L. Riskin
Evaluating effects of potential changes in streamflow regime on fish and aquatic-invertebrate assemblages in the New Jersey Pinelands
Changes in water demand associated with population growth and changes in land-use practices in the Pinelands region of southern New Jersey will have a direct effect on stream hydrology. The most pronounced and measurable hydrologic effect is likely to be flow reductions associated with increasing water extraction. Because water-supply needs will continue to grow along with population in...
Authors
Jonathan Kennen, Melissa L. Riskin
Mercury and methylmercury dynamics in a coastal plain watershed, New Jersey, USA
The upper Great Egg Harbor River watershed in New Jersey's Coastal Plain is urbanized but extensive freshwater wetlands are present downstream. In 2006-2007, studies to assess levels of total mercury (THg) found concentrations in unfiltered streamwater to range as high as 187 ng/L in urbanized areas. THg concentrations were
Authors
J. L. Barringer, M.L. Riskin, Z. Szabo, P.A. Reilly, R. Rosman, J.L. Bonin, J.M. Fischer, H.A. Heckathorn
Water resources data, New Jersey, water year 2004--volume 3. water-quality data
No abstract available.
Authors
Michael J. DeLuca, Heather A. Heckathorn, Jason M. Lewis, Bonnie J. Gray, Emma-Lynn Melvin, Melissa L. Riskin, Nicholas A. Liu
Science and Products
Concentrations of 6PPD and 6PPD-Quinone in a United States reconnaissance of stormwater, surface water, and groundwater, 2018-24
From 2018 to 2024 surface waters (fresh and brackish), groundwater, and stormwater (runoff, re-use) samples were collected from sites with varying landuse (agricultural, forested, and urban) and streamflow conditions and analyzed at the Organic Geochemistry Research Laboratory in Lawrence, Kansas for the tire antioxidant 6PPD (6-p-phenylenediamine; N-(1,3-Dimethylbutyl)-N’-phenyl-p...
Evaluation of preservation techniques for trace metals and major cations for surface waters collected from the U.S. Geological Survey's National Water Quality Network Sites
The USGS National Field Manual (NFM) states "A representative sample is one that typifies in time and space that part of the aqueous system to be studied" and "obtaining representative samples is of primary importance for a relevant description of the environment." The NFM contains detailed chapters on the best practices for representative and contamination free sampling of major and...
Water-quality and streamflow datasets used in Weighted Regressions on Time, Discharge, and Season (WRTDS) models to determine trends in the Nation’s rivers and streams, 1972-2017
In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project. One of the major goals of the NAWQA project was to determine how river water quality has changed over time. To support that goal, long-term consistent and comparable monitoring has been conducted by the USGS on...
Pesticide datasets from the National Water Quality Laboratory: a review of recent practices of censoring scenarios for select groundwater and surfacewater results, 2001-2015
This data release includes all pesticide results from selected batches of water samples analyzed by the U.S Geological Survey National Water Quality Laboratory (NWQL). Samples were analyzed using gas chromatography/mass spectrometry (GCMS) or liquid chromatography/mass spectrometry (LCMS) methods. Eight datasets are included in this data release; 1) all environmental and field quality...
Daily streamflow datasets used to analyze trends in streamflow at sites also analyzed for trends in water quality and ecological condition in the Nation's rivers and streams
In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring...
Ecological community datasets used to evaluate the presence of trends in ecological communities in selected rivers and streams across the United States, 1992-2012
In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality and ecological conditions change over time. To support that goal, long-term consistent and...
Pesticide concentration and streamflow datasets used to evaluate pesticide trends in the Nations rivers and streams, 1992-2012
In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring...
Filter Total Items: 17
The U.S. Geological Survey National Water Quality Network—Surface Water—2023
The U.S. Geological Survey (USGS) National Water Quality Network for surface water (NWQN-SW) was established in 2013 to develop long-term, comparable assessments of surface-water quality in support of national, regional, state, and local needs related to water-quality management and policy. Waterquality samples are collected at each site and measured for a variety of parameters. In 2023...
Authors
Melissa L. Riskin
USGS National Water Quality Monitoring Network
What is the U.S. Geological Survey National Water Quality Monitoring Network?Understanding the water quality of U.S. streams and rivers requires consistent data collection and analysis over decades. The U.S. Geological Survey’s (USGS) National Water Quality Network (NWQN) was established to facilitate national-scale understanding of surface-water quality conditions through the collection...
Authors
Melissa L. Riskin, Casey J. Lee
Landscape drivers of dynamic change in water quality of US rivers
Water security is a top concern for social well-being and dramatic changes in the availability of freshwater have occurred as a result of human uses and landscape management. Elevated nutrient loading and perturbations to major ion composition have resulted from human activities and have degraded freshwater resources. This study addresses the emerging nature of stream water quality in...
Authors
Edward G. Stets, Lori A. Sprague, Gretchen P. Oelsner, Henry M. Johnson, Jennifer C. Murphy, Karen R. Ryberg, Aldo V. Vecchia, Robert E. Zuellig, James A. Falcone, Melissa L. Riskin
Use of set blanks in reporting pesticide results at the U.S. Geological Survey National Water Quality Laboratory, 2001-15
Executive SummaryBackground.—Pesticide results from the U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL) are used for water-quality assessments by many agencies and organizations. The USGS is committed to providing data of the highest possible quality to the consumers of its data. A cooperator’s inquiries about specific pesticide detections in water revealed...
Authors
Laura Medalie, Mark W. Sandstrom, Patricia L. Toccalino, William T. Foreman, Rhiannon C. ReVello, Laura M. Bexfield, Melissa L. Riskin
Water-quality trends in U.S. rivers, 2002 to 2012: Relations to levels of concern
Effective management and protection of water resources relies upon understanding how water-quality conditions are changing over time. Water-quality trends for ammonia, chloride, nitrate, sulfate, total dissolved solids (TDS), total nitrogen (TN) and total phosphorus (TP) were assessed at 762 sites located in the conterminous United States between 2002 and 2012. Annual mean concentrations...
Authors
Megan E. Shoda, Lori A. Sprague, Jennifer C. Murphy, Melissa L. Riskin
Quality-control design for surface-water sampling in the National Water-Quality Network
The data-quality objectives for samples collected at surface-water sites in the National Water-Quality Network include estimating the extent to which contamination, matrix effects, and measurement variability affect interpretation of environmental conditions. Quality-control samples provide insight into how well the samples collected at surface-water sites represent the true...
Authors
Melissa L. Riskin, David C. Reutter, Jeffrey D. Martin, David K. Mueller
Water-quality trends in the nation’s rivers and streams, 1972–2012—Data preparation, statistical methods, and trend results
Since passage of the Clean Water Act in 1972, Federal, State, and local governments have invested billions of dollars to reduce pollution entering rivers and streams. To understand the return on these investments and to effectively manage and protect the Nation’s water resources in the future, we need to know how and why water quality has been changing over time. As part of the National...
Authors
Gretchen P. Oelsner, Lori A. Sprague, Jennifer C. Murphy, Robert E. Zuellig, Henry M. Johnson, Karen R. Ryberg, James A. Falcone, Edward G. Stets, Aldo V. Vecchia, Melissa L. Riskin, Laura A. De Cicco, Taylor J. Mills, William H. Farmer
Method to support Total Maximum Daily Load development using hydrologic alteration as a surrogate to address aquatic life impairment in New Jersey streams
More than 300 ambient monitoring sites in New Jersey have been identified by the New Jersey Department of Environmental Protection (NJDEP) in its integrated water-quality monitoring and assessment report (that is, the 305(b) Report on general water quality and 303(d) List of waters that do not support their designated uses) as being impaired with respect to aquatic life; however, no...
Authors
Jonathan Kennen, Melissa L. Riskin, Pamela A. Reilly, Susan J. Colarullo
Variable contributions of mercury from groundwater to a first-order urban coastal plain stream in New Jersey, USA
Filtered total mercury (FTHg) concentrations in a rapidly urbanizing area ranged from 50 to 250 ng/L in surface waters of the Squankum Branch, a tributary to a major river (Great Egg Harbor River (GEHR)) traversing both urban and forested/wetland areas in the Coastal Plain of New Jersey. An unsewered residential area with Hg-contaminated well water (one of many in the region) is adjacent...
Authors
Julia Barringer, Zoltan Szabo, Pamela A. Reilly, Melissa L. Riskin
Evaluating effects of potential changes in streamflow regime on fish and aquatic-invertebrate assemblages in the New Jersey Pinelands
Changes in water demand associated with population growth and changes in land-use practices in the Pinelands region of southern New Jersey will have a direct effect on stream hydrology. The most pronounced and measurable hydrologic effect is likely to be flow reductions associated with increasing water extraction. Because water-supply needs will continue to grow along with population in...
Authors
Jonathan Kennen, Melissa L. Riskin
Mercury and methylmercury dynamics in a coastal plain watershed, New Jersey, USA
The upper Great Egg Harbor River watershed in New Jersey's Coastal Plain is urbanized but extensive freshwater wetlands are present downstream. In 2006-2007, studies to assess levels of total mercury (THg) found concentrations in unfiltered streamwater to range as high as 187 ng/L in urbanized areas. THg concentrations were
Authors
J. L. Barringer, M.L. Riskin, Z. Szabo, P.A. Reilly, R. Rosman, J.L. Bonin, J.M. Fischer, H.A. Heckathorn
Water resources data, New Jersey, water year 2004--volume 3. water-quality data
No abstract available.
Authors
Michael J. DeLuca, Heather A. Heckathorn, Jason M. Lewis, Bonnie J. Gray, Emma-Lynn Melvin, Melissa L. Riskin, Nicholas A. Liu