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Craig J Brown, Ph.D. (Former Employee)

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Hydrogeologic and Geochemical Assessment of the Effects of Leakage from the Catskill and Delaware Aqueducts on the Local Bedrock and Overburden Aquifers in Southeastern New York

PROBLEM As part of an effort to sustain a viable water-supply system for 8 million residents in New York City, and 1 million other residents in upstate New York that rely on City water, the New York City Department of Environmental Protection (NYCDEP) has requested a multi-disciplinary study by the U.S. Geological Survey (USGS) to determine the source(s) of water to surface-water sites...
By
New York Water Science Center
link

Hydrogeologic and Geochemical Assessment of the Effects of Leakage from the Catskill and Delaware Aqueducts on the Local Bedrock and Overburden Aquifers in Southeastern New York

PROBLEM As part of an effort to sustain a viable water-supply system for 8 million residents in New York City, and 1 million other residents in upstate New York that rely on City water, the New York City Department of Environmental Protection (NYCDEP) has requested a multi-disciplinary study by the U.S. Geological Survey (USGS) to determine the source(s) of water to surface-water sites (springs
Learn More

Model and Data Resources Supporting Water-Quality Modeling of Hydrologic Systems

This dataset provides detailed information on availability of model resources (including models and datasets) that support the modeling of six key water-quality constituents (or constituent categories) across the hydrologic system. In addition, resources associated with nine “cross-cutting” topics for modeling water quality are included, with “cross-cutting” defined herein as having...
By
New England Water Science Center

Data and Model Archive for Simulations of Seawater Restoration on Diked Salt Marshes

This dataset and model archive provides geochemical modeling input and selected output data used in simulations of seawater restoration on historically diked salt marshes. Biogeochemical changes resulting from seawater reintroduction were simulated using the computer program PHREEQC (Parkhurst and Appelo, 2013) to help support efforts to restore tidal flow and associated estuarine...
By
New England Water Science Center

Data for Occurrence and Sources of Lead in Private Wells, Sturbridge, Massachusetts

This dataset contains water-quality data, quality-control data, and input and output data for geochemical models that support the findings of a study of lead in drinking water in the Sturbridge, Massachusetts, study area. These data include major and trace element data for unfiltered and filtered (dissolved) samples collected from both taps and well heads at private well sites, and...
By
New England Water Science Center

Data for machine learning predictions of pH in the glacial aquifer system, northern USA

A boosted regression tree (BRT) model was developed to predict pH conditions in three-dimensions throughout the glacial aquifer system (GLAC) of the contiguous United States using pH measurements in samples from 18,258 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of soils and aquifer materials...
By
Water Resources Mission Area

Inventory of well-construction data, water-quality and quality control data, statistical data, and geochemical modeling data for wells in Atlantic and Gulf Coastal Plain aquifers, eastern United States, 2012 and 2013

This dataset provides analytical and other data in support of an analysis of lead and manganese in untreated drinking water from Atlantic and Gulf Coastal Plain aquifers, eastern United States. The occurrence of dissolved lead and manganese in sampled groundwater, prior to its distribution or treatment, is related to the potential presence of source minerals and specific environmental...
By
Lower Mississippi-Gulf Water Science Center

Inventory of arsenic and uranium water-quality results from private wells in Connecticut, 2013-2015

This dataset contains the water-quality results from the testing of unfiltered water samples collected from 674 private wells in Connecticut for the analysis of arsenic and (or) uranium, using EPA method 200.8. All of the environmental water-quality data and georeferenced locations of the sampled wells were provided by the Connecticut Department of Public Health (CT-DPH). The water...
By
New England Water Science Center
Image: SWaTH Nework Bracket Level
SWaTH Nework Bracket Level
SWaTH Nework Bracket Level
Image: SWaTH Nework Bracket Level

SWaTH Nework Bracket Level

SWaTH Nework Bracket Level

Tim Sargent, a hydrology tech at the New England Water Science Center, is checking to make sure that the bracket he installed is level.

By
Natural Hazards Mission Area, Communications and Publishing
Image: SWaTH Nework Bracket Level

SWaTH Nework Bracket Level

SWaTH Nework Bracket Level

Tim Sargent, a hydrology tech at the New England Water Science Center, is checking to make sure that the bracket he installed is level.

By
Natural Hazards Mission Area, Communications and Publishing
Filter Total Items: 28

Gaps in water quality modeling of hydrologic systems

This review assesses gaps in water quality modeling, emphasizing opportunities to improve next-generation models that are essential for managing water quality and are integral to meeting goals of scientific and management agencies. In particular, this paper identifies gaps in water quality modeling capabilities that, if addressed, could support assessments, projections, and evaluations...
Authors
Lisa Lucas, Craig J. Brown, Dale M. Robertson, Nancy T. Baker, Zachary Johnson, Christopher T. Green, Se Jong Cho, Melinda Erickson, Allen C. Gellis, Jeramy Roland Jasmann, Noah Knowles, Andreas Prein, Paul E. Stackelberg
By
Water Resources Mission Area

Prioritizing US Geological Survey science on salinization and salinity in candidate and selected priority river basins

The US Geological Survey (USGS) is selecting and prioritizing basins, known as Integrated Water Science basins, for monitoring and intensive study. Previous efforts to aid in this selection process include a scientifically defensible and quantitative assessment of basins facing human-caused water resource challenges (Van Metre et al. in Environmental Monitoring and Assessment, 192(7)...
Authors
Christopher Conaway, Nancy T. Baker, Craig J. Brown, Christopher T. Green, Douglas B. Kent
By
Water Resources Mission Area, New England Water Science Center, Ohio-Kentucky-Indiana Water Science Center

Prioritizing water availability study settings to address geogenic contaminants and related societal factors

Water availability for human and ecological uses depends on both water quantity and water quality. The U.S. Geological Survey (USGS) is developing strategies for prioritizing regional-scale and watershed basin-scale studies of water availability across the nation. Previous USGS ranking processes for basin-scale studies incorporated primarily water quantity factors but are now considering...
Authors
Melinda Erickson, Craig J. Brown, Elizabeth J. Tomaszewski, Joseph D. Ayotte, Sharon L. Qi, Douglas B. Kent, J.K. Böhlke
By
Water Resources Mission Area

Estimating lithium concentrations in groundwater used as drinking water for the conterminous United States

Lithium (Li) concentrations in drinking-water supplies are not regulated in the United States; however, Li is included in the 2022 U.S. Environmental Protection Agency list of unregulated contaminants for monitoring by public water systems. Li is used pharmaceutically to treat bipolar disorder, and studies have linked its occurrence in drinking water to human-health outcomes. An extreme...
Authors
Melissa Lombard, Eric K. Brown, Daniel Saftner, Monica M. Arienzo, Esme Fuller-Thomson, Craig J. Brown, Joseph D. Ayotte
By
Water Resources Mission Area, New England Water Science Center

Occurrence and sources of lead in private wells, Sturbridge, Massachusetts

Lead (Pb) occurrence and sources and aqueous geochemistry were assessed in private wellhead and tap water at a targeted area of concern for possible exceedances and at a control area in the same geologic formation, and in wells at a nearby landfill in south-central Massachusetts (MA). Total Pb concentrations were below the U.S. Environmental Protection Agency (USEPA) Action Level of 15...
Authors
Leah M. Santangelo, Craig J. Brown, James B. Shanley, Michael Pribil, Danny Rutherford
By
Water Resources Mission Area, Geology, Geophysics, and Geochemistry Science Center, New England Water Science Center

Machine-learning predictions of high arsenic and high manganese at drinking water depths of the glacial aquifer system, northern continental United States

Globally, over 200 million people are chronically exposed to arsenic (As) and/or manganese (Mn) from drinking water. We used machine-learning (ML) boosted regression tree (BRT) models to predict high As (>10 μg/L) and Mn (>300 μg/L) in groundwater from the glacial aquifer system (GLAC), which spans 25 states in the northern United States and provides drinking water to 30 million people...
Authors
Melinda Erickson, Sarah M. Elliott, Craig J. Brown, Paul E. Stackelberg, Katherine Marie Ransom, James E. Reddy, Charles A. Cravotta
By
Water Resources Mission Area, California Water Science Center, New England Water Science Center, New York Water Science Center, Pennsylvania Water Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Machine learning predicted redox conditions in the glacial aquifer system, northern continental United States

Groundwater supplies 50% of drinking water worldwide and 30% in the United States. Geogenic and anthropogenic contaminants can, however, compromise water quality, thus limiting groundwater availability. Reduction/oxidation (redox) processes and redox conditions affect groundwater quality by influencing the mobility and transport of common geogenic and anthropogenic contaminants. In the...
Authors
Melinda Erickson, Sarah M. Elliott, Craig J. Brown, Paul E. Stackelberg, Katherine Marie Ransom, James E. Reddy
By
Water Resources Mission Area, California Water Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center, New York Water Science Center

Machine learning predictions of pH in the Glacial Aquifer System, Northern USA

A boosted regression tree model was developed to predict pH conditions in three dimensions throughout the glacial aquifer system of the contiguous United States using pH measurements in samples from 18,386 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of soils and aquifer materials strongly controls pH...
Authors
Paul E. Stackelberg, Kenneth Belitz, Craig J. Brown, Melinda Erickson, Sarah M. Elliott, Leon J. Kauffman, Katherine Marie Ransom, James E. Reddy
By
Water Resources Mission Area

Arsenic and uranium occurrence in private wells in Connecticut, 2013–18—A spatially weighted and bedrock geology assessment

The U.S. Geological Survey, in cooperation with the Connecticut Department of Public Health, conducted a study to determine the presence of arsenic and uranium in private drinking water wells in Connecticut. Samples were collected during 2013–18 from wells completed in 115 geologic units, with 2,433 samples analyzed for arsenic and 2,191 samples analyzed for uranium. The study concluded...
Authors
Eliza L. Gross, Craig J. Brown
By
Water Resources Mission Area, New York Water Science Center, Pennsylvania Water Science Center

A multi-model approach toward understanding iron fouling at rock-fill drainage sites along roadways in New Hampshire, USA

Factors affecting iron fouling in wet areas adjacent to roadways were investigated by collecting field rock cut and aqueous physicochemical data; developing exploratory predictive models; and developing geochemical models. Basic data included the identification of iron fouling from aerial imagery and field visits at 374 New Hampshire rock cut locations, and their associated rock-fill...
Authors
Melissa Lombard, Pamela J. Lombard, Craig J. Brown, James R. Degnan
By
Water Resources Mission Area, New England Water Science Center

Fluoride occurrence in United States groundwater

Data from 38,105 wells were used to characterize fluoride (F) occurrence in untreated United States (U.S.) groundwater. For domestic wells (n = 11,032), water from which is generally not purposely fluoridated or monitored for quality, 10.9% of the samples have F concentrations >0.7 mg/L (U.S. Public Health Service recommended optimal F concentration in drinking water for preventing tooth...
Authors
Peter B. McMahon, Craig J. Brown, Tyler Johnson, Kenneth Belitz, Bruce Lindsey
By
Water Resources Mission Area, California Water Science Center, Colorado Water Science Center, New England Water Science Center, Pennsylvania Water Science Center

Factors affecting the occurrence of lead and manganese in untreated drinking water from Atlantic and Gulf Coastal Plain aquifers, eastern United States—Dissolved oxygen and pH framework for evaluating risk of elevated concentrations

Groundwater samples collected during 2012 and 2013 from public-supply wells screened in the Atlantic and Gulf Coastal Plain aquifers of the eastern and southeastern U.S. rarely contained lead or manganese concentrations that exceeded drinking-water limits, despite having corrosive characteristics. Data indicate that the occurrence of dissolved lead and manganese in sampled groundwater...
Authors
Craig J. Brown, Jeannie R. B. Barlow, Charles A. Cravotta, Bruce Lindsey
By
Water Resources Mission Area, New England Water Science Center, Pennsylvania Water Science Center

Non-USGS Publications**

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

Science and Products

link
orange colored area on a white map

Hydrogeologic and Geochemical Assessment of the Effects of Leakage from the Catskill and Delaware Aqueducts on the Local Bedrock and Overburden Aquifers in Southeastern New York

PROBLEM As part of an effort to sustain a viable water-supply system for 8 million residents in New York City, and 1 million other residents in upstate New York that rely on City water, the New York City Department of Environmental Protection (NYCDEP) has requested a multi-disciplinary study by the U.S. Geological Survey (USGS) to determine the source(s) of water to surface-water sites...
By
New York Water Science Center
link

Hydrogeologic and Geochemical Assessment of the Effects of Leakage from the Catskill and Delaware Aqueducts on the Local Bedrock and Overburden Aquifers in Southeastern New York

PROBLEM As part of an effort to sustain a viable water-supply system for 8 million residents in New York City, and 1 million other residents in upstate New York that rely on City water, the New York City Department of Environmental Protection (NYCDEP) has requested a multi-disciplinary study by the U.S. Geological Survey (USGS) to determine the source(s) of water to surface-water sites (springs
Learn More

Model and Data Resources Supporting Water-Quality Modeling of Hydrologic Systems

This dataset provides detailed information on availability of model resources (including models and datasets) that support the modeling of six key water-quality constituents (or constituent categories) across the hydrologic system. In addition, resources associated with nine “cross-cutting” topics for modeling water quality are included, with “cross-cutting” defined herein as having...
By
New England Water Science Center

Data and Model Archive for Simulations of Seawater Restoration on Diked Salt Marshes

This dataset and model archive provides geochemical modeling input and selected output data used in simulations of seawater restoration on historically diked salt marshes. Biogeochemical changes resulting from seawater reintroduction were simulated using the computer program PHREEQC (Parkhurst and Appelo, 2013) to help support efforts to restore tidal flow and associated estuarine...
By
New England Water Science Center

Data for Occurrence and Sources of Lead in Private Wells, Sturbridge, Massachusetts

This dataset contains water-quality data, quality-control data, and input and output data for geochemical models that support the findings of a study of lead in drinking water in the Sturbridge, Massachusetts, study area. These data include major and trace element data for unfiltered and filtered (dissolved) samples collected from both taps and well heads at private well sites, and...
By
New England Water Science Center

Data for machine learning predictions of pH in the glacial aquifer system, northern USA

A boosted regression tree (BRT) model was developed to predict pH conditions in three-dimensions throughout the glacial aquifer system (GLAC) of the contiguous United States using pH measurements in samples from 18,258 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of soils and aquifer materials...
By
Water Resources Mission Area

Inventory of well-construction data, water-quality and quality control data, statistical data, and geochemical modeling data for wells in Atlantic and Gulf Coastal Plain aquifers, eastern United States, 2012 and 2013

This dataset provides analytical and other data in support of an analysis of lead and manganese in untreated drinking water from Atlantic and Gulf Coastal Plain aquifers, eastern United States. The occurrence of dissolved lead and manganese in sampled groundwater, prior to its distribution or treatment, is related to the potential presence of source minerals and specific environmental...
By
Lower Mississippi-Gulf Water Science Center

Inventory of arsenic and uranium water-quality results from private wells in Connecticut, 2013-2015

This dataset contains the water-quality results from the testing of unfiltered water samples collected from 674 private wells in Connecticut for the analysis of arsenic and (or) uranium, using EPA method 200.8. All of the environmental water-quality data and georeferenced locations of the sampled wells were provided by the Connecticut Department of Public Health (CT-DPH). The water...
By
New England Water Science Center
Image: SWaTH Nework Bracket Level
SWaTH Nework Bracket Level
SWaTH Nework Bracket Level
Image: SWaTH Nework Bracket Level

SWaTH Nework Bracket Level

SWaTH Nework Bracket Level

Tim Sargent, a hydrology tech at the New England Water Science Center, is checking to make sure that the bracket he installed is level.

By
Natural Hazards Mission Area, Communications and Publishing
Image: SWaTH Nework Bracket Level

SWaTH Nework Bracket Level

SWaTH Nework Bracket Level

Tim Sargent, a hydrology tech at the New England Water Science Center, is checking to make sure that the bracket he installed is level.

By
Natural Hazards Mission Area, Communications and Publishing
Filter Total Items: 28

Gaps in water quality modeling of hydrologic systems

This review assesses gaps in water quality modeling, emphasizing opportunities to improve next-generation models that are essential for managing water quality and are integral to meeting goals of scientific and management agencies. In particular, this paper identifies gaps in water quality modeling capabilities that, if addressed, could support assessments, projections, and evaluations...
Authors
Lisa Lucas, Craig J. Brown, Dale M. Robertson, Nancy T. Baker, Zachary Johnson, Christopher T. Green, Se Jong Cho, Melinda Erickson, Allen C. Gellis, Jeramy Roland Jasmann, Noah Knowles, Andreas Prein, Paul E. Stackelberg
By
Water Resources Mission Area

Prioritizing US Geological Survey science on salinization and salinity in candidate and selected priority river basins

The US Geological Survey (USGS) is selecting and prioritizing basins, known as Integrated Water Science basins, for monitoring and intensive study. Previous efforts to aid in this selection process include a scientifically defensible and quantitative assessment of basins facing human-caused water resource challenges (Van Metre et al. in Environmental Monitoring and Assessment, 192(7)...
Authors
Christopher Conaway, Nancy T. Baker, Craig J. Brown, Christopher T. Green, Douglas B. Kent
By
Water Resources Mission Area, New England Water Science Center, Ohio-Kentucky-Indiana Water Science Center

Prioritizing water availability study settings to address geogenic contaminants and related societal factors

Water availability for human and ecological uses depends on both water quantity and water quality. The U.S. Geological Survey (USGS) is developing strategies for prioritizing regional-scale and watershed basin-scale studies of water availability across the nation. Previous USGS ranking processes for basin-scale studies incorporated primarily water quantity factors but are now considering...
Authors
Melinda Erickson, Craig J. Brown, Elizabeth J. Tomaszewski, Joseph D. Ayotte, Sharon L. Qi, Douglas B. Kent, J.K. Böhlke
By
Water Resources Mission Area

Estimating lithium concentrations in groundwater used as drinking water for the conterminous United States

Lithium (Li) concentrations in drinking-water supplies are not regulated in the United States; however, Li is included in the 2022 U.S. Environmental Protection Agency list of unregulated contaminants for monitoring by public water systems. Li is used pharmaceutically to treat bipolar disorder, and studies have linked its occurrence in drinking water to human-health outcomes. An extreme...
Authors
Melissa Lombard, Eric K. Brown, Daniel Saftner, Monica M. Arienzo, Esme Fuller-Thomson, Craig J. Brown, Joseph D. Ayotte
By
Water Resources Mission Area, New England Water Science Center

Occurrence and sources of lead in private wells, Sturbridge, Massachusetts

Lead (Pb) occurrence and sources and aqueous geochemistry were assessed in private wellhead and tap water at a targeted area of concern for possible exceedances and at a control area in the same geologic formation, and in wells at a nearby landfill in south-central Massachusetts (MA). Total Pb concentrations were below the U.S. Environmental Protection Agency (USEPA) Action Level of 15...
Authors
Leah M. Santangelo, Craig J. Brown, James B. Shanley, Michael Pribil, Danny Rutherford
By
Water Resources Mission Area, Geology, Geophysics, and Geochemistry Science Center, New England Water Science Center

Machine-learning predictions of high arsenic and high manganese at drinking water depths of the glacial aquifer system, northern continental United States

Globally, over 200 million people are chronically exposed to arsenic (As) and/or manganese (Mn) from drinking water. We used machine-learning (ML) boosted regression tree (BRT) models to predict high As (>10 μg/L) and Mn (>300 μg/L) in groundwater from the glacial aquifer system (GLAC), which spans 25 states in the northern United States and provides drinking water to 30 million people...
Authors
Melinda Erickson, Sarah M. Elliott, Craig J. Brown, Paul E. Stackelberg, Katherine Marie Ransom, James E. Reddy, Charles A. Cravotta
By
Water Resources Mission Area, California Water Science Center, New England Water Science Center, New York Water Science Center, Pennsylvania Water Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Machine learning predicted redox conditions in the glacial aquifer system, northern continental United States

Groundwater supplies 50% of drinking water worldwide and 30% in the United States. Geogenic and anthropogenic contaminants can, however, compromise water quality, thus limiting groundwater availability. Reduction/oxidation (redox) processes and redox conditions affect groundwater quality by influencing the mobility and transport of common geogenic and anthropogenic contaminants. In the...
Authors
Melinda Erickson, Sarah M. Elliott, Craig J. Brown, Paul E. Stackelberg, Katherine Marie Ransom, James E. Reddy
By
Water Resources Mission Area, California Water Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center, New York Water Science Center

Machine learning predictions of pH in the Glacial Aquifer System, Northern USA

A boosted regression tree model was developed to predict pH conditions in three dimensions throughout the glacial aquifer system of the contiguous United States using pH measurements in samples from 18,386 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of soils and aquifer materials strongly controls pH...
Authors
Paul E. Stackelberg, Kenneth Belitz, Craig J. Brown, Melinda Erickson, Sarah M. Elliott, Leon J. Kauffman, Katherine Marie Ransom, James E. Reddy
By
Water Resources Mission Area

Arsenic and uranium occurrence in private wells in Connecticut, 2013–18—A spatially weighted and bedrock geology assessment

The U.S. Geological Survey, in cooperation with the Connecticut Department of Public Health, conducted a study to determine the presence of arsenic and uranium in private drinking water wells in Connecticut. Samples were collected during 2013–18 from wells completed in 115 geologic units, with 2,433 samples analyzed for arsenic and 2,191 samples analyzed for uranium. The study concluded...
Authors
Eliza L. Gross, Craig J. Brown
By
Water Resources Mission Area, New York Water Science Center, Pennsylvania Water Science Center

A multi-model approach toward understanding iron fouling at rock-fill drainage sites along roadways in New Hampshire, USA

Factors affecting iron fouling in wet areas adjacent to roadways were investigated by collecting field rock cut and aqueous physicochemical data; developing exploratory predictive models; and developing geochemical models. Basic data included the identification of iron fouling from aerial imagery and field visits at 374 New Hampshire rock cut locations, and their associated rock-fill...
Authors
Melissa Lombard, Pamela J. Lombard, Craig J. Brown, James R. Degnan
By
Water Resources Mission Area, New England Water Science Center

Fluoride occurrence in United States groundwater

Data from 38,105 wells were used to characterize fluoride (F) occurrence in untreated United States (U.S.) groundwater. For domestic wells (n = 11,032), water from which is generally not purposely fluoridated or monitored for quality, 10.9% of the samples have F concentrations >0.7 mg/L (U.S. Public Health Service recommended optimal F concentration in drinking water for preventing tooth...
Authors
Peter B. McMahon, Craig J. Brown, Tyler Johnson, Kenneth Belitz, Bruce Lindsey
By
Water Resources Mission Area, California Water Science Center, Colorado Water Science Center, New England Water Science Center, Pennsylvania Water Science Center

Factors affecting the occurrence of lead and manganese in untreated drinking water from Atlantic and Gulf Coastal Plain aquifers, eastern United States—Dissolved oxygen and pH framework for evaluating risk of elevated concentrations

Groundwater samples collected during 2012 and 2013 from public-supply wells screened in the Atlantic and Gulf Coastal Plain aquifers of the eastern and southeastern U.S. rarely contained lead or manganese concentrations that exceeded drinking-water limits, despite having corrosive characteristics. Data indicate that the occurrence of dissolved lead and manganese in sampled groundwater...
Authors
Craig J. Brown, Jeannie R. B. Barlow, Charles A. Cravotta, Bruce Lindsey
By
Water Resources Mission Area, New England Water Science Center, Pennsylvania Water Science Center

Non-USGS Publications**

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

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