Martha G Nielsen
Martha Nielsen is a Hydrologist with the Upper Midwest Water Science Center.
Science and Products
New England Water Use
Monthly water use estimates for New England and the rest of the conterminous U.S. are now available for the three largest categories of use in the United States: public supply, crop irrigation, and thermoelectric power generation.
Recharge Estimates for Maine: 25-year Average, Range, and Uncertainty, 1990-2015
The USGS Soil-Water-Balance model (SWB) has been used to estimate potential recharge across the State of Maine. The average and range (minimum and maximum) of annual recharge were estimated for the 25-year period from 1990 to 2015. Datasets of estimated recharge and the modeled uncertainty in the recharge estimates are available for download.
Data for improved understanding of the susceptibility of Lake Superior to threats from groundwater contamination Data for improved understanding of the susceptibility of Lake Superior to threats from groundwater contamination
This data release contains a data compilation and analysis of the hydrogeology in the U.S. portion of the Lake Superior watershed, for the purpose of providing background data for future study and modeling of groundwater and contaminant movement in the watershed. The data support an analysis of groundwater contributions to the water budget of Lake Superior and provide hydrogeologic...
Model archive and output files for net infiltration, runoff, and irrigation water use for the Mississippi Embayment Regional Aquifer System, 2000 to 2020, simulated with the Soil-Water-Balance model Model archive and output files for net infiltration, runoff, and irrigation water use for the Mississippi Embayment Regional Aquifer System, 2000 to 2020, simulated with the Soil-Water-Balance model
This item provides Soil-Water-Balance (SWB) model output and a model archive of water budget simulations for the Mississippi Embayment Regional Aquifer System (MERAS) during the period 2000 to 2020. Gridded daily data (1 kilometer resolution) include net infiltration (groundwater recharge), rejected net infiltration, runoff, irrigation, actual evapotranspiration and gross precipitation...
Prototype updated principal aquifer datasets for three aquifer systems in the Upper Midwest, USA Prototype updated principal aquifer datasets for three aquifer systems in the Upper Midwest, USA
This geospatial dataset represents a prototype of a finer-scale representation of the principal aquifers of the United States, using four original principal aquifers in the Upper Midwest, United States, which were re-analyzed and condensed into three updated principal aquifers. The original principal aquifer definitions and extents were published in the Ground Water Atlas of the United...
Soil-Water-Balance (SWB) model archive used to simulate potential annual recharge for the former Badger Army Ammunition Plant study area, Prairie du Sac, Wisconsin, 1980 to 2020 Soil-Water-Balance (SWB) model archive used to simulate potential annual recharge for the former Badger Army Ammunition Plant study area, Prairie du Sac, Wisconsin, 1980 to 2020
This model archive makes available the U.S. Geological Survey Soil-Water-Balance (SWB) model created in support of a groundwater flow model of the former Badger Army Ammunition Plant in Sauk County, Wisconsin. The SWB model provides initial estimates of potential recharge to the groundwater system in the study area, which are used in a calibrated 3-dimensional MODFLOW (modular finite...
Upper Midwest Water Science Center Groundwater Model Archive Index v1.0 2023 Upper Midwest Water Science Center Groundwater Model Archive Index v1.0 2023
This vector geospatial dataset contains bounding polygons that visualize the domain of archived groundwater flow models published by the Upper Midwest Water Science Center and attributes pertaining to the associated publication (citation, year of publication, authors, report ID, publication URL), model construction details, and a URL for publicly available model archives when available...
OFR 2021-1008 MODEL ARCHIVE: Soil-Water-Balance model developed to simulate net infiltration and irrigation water use for the Mississippi Embayment Regional Aquifer System, 1915 to 2018 OFR 2021-1008 MODEL ARCHIVE: Soil-Water-Balance model developed to simulate net infiltration and irrigation water use for the Mississippi Embayment Regional Aquifer System, 1915 to 2018
This model archive makes available the calibrated Soil-Water-Balance (SWB) model used to simulate potential recharge for the Mississippi Alluvial Aquifer for 1915 to 2018. The model was calibrated using monthly values of evapotranspiration and annual values of runoff and recharge for 19 drainage basins selected from within or nearby the Mississippi Alluvial Aquifer system. The calibrated...
OFR 2021-1008 MODEL OUTPUT: Soil-Water-Balance net infiltration and irrigation water use output datasets for the Mississippi Embayment Regional Aquifer System, 1915 to 2018 OFR 2021-1008 MODEL OUTPUT: Soil-Water-Balance net infiltration and irrigation water use output datasets for the Mississippi Embayment Regional Aquifer System, 1915 to 2018
This data release includes four sets of gridded annual net infiltration (groundwater recharge) and irrigation water use data sets for the Mississippi Embayment Regional Aquifer System (MERAS).Also included are gridded water balance component data sets of precipitation, runoff, actual evapotranspiration, and soil-water storage for 2000 to 2018. The net infiltration, irrigation, runoff...
Estimated Groundwater Withdrawals from Principal Aquifers in the United States--County Level Data for 2015 Estimated Groundwater Withdrawals from Principal Aquifers in the United States--County Level Data for 2015
This dataset contains estimates of water withdrawals from 66 principal aquifers and "other" non-principal aquifers during 2015 for various categories of use in each county or county equivalent in the United States, Puerto Rico, and the U.S. Virgin Islands. The U.S. Geological Survey's (USGS) National Water Use Science Project is responsible for compiling and disseminating the Nation's...
Simulated 25-year potential annual recharge datasets for Maine, 1991-2015 Simulated 25-year potential annual recharge datasets for Maine, 1991-2015
This set of data includes four potential annual recharge grids for the State of Maine that were simulated using the Maine Soil-Water-Balance model for 1991 through 2015. The files include a grid representing the uncertainty in the potential recharge and a grid showing the annual average precipitation from the climate dataset that the simulation is based on. A 25-year simulation of...
Soil-Water-Balance (SWB) model archive used to simulate potential annual recharge in Maine, 1991-2015 Soil-Water-Balance (SWB) model archive used to simulate potential annual recharge in Maine, 1991-2015
This set of data includes four potential annual recharge grids for the State of Maine that were simulated using the Maine Soil-Water-Balance model for 1991 through 2015. The files include a grid representing the uncertainty in the potential recharge and a grid showing the annual average precipitation from the climate dataset that the simulation is based on. A 25-year simulation of...
Data related to the degree of potential human influence near 2228 groundwater wells in the U.S. glacial aquifer system Data related to the degree of potential human influence near 2228 groundwater wells in the U.S. glacial aquifer system
This dataset contains information on the degree of potential human influence near 2228 groundwater wells in the U.S. glacial aquifer system. Data include well identification, name, latitude, longitude, potential-human-influence category, percent urban and crop land use in a 500 meter radius around each well, and measures of county-based groundwater use and irrigation.
Filter Total Items: 27
Using hydrogeologic context and water budgets to evaluate the potential for groundwater contributions to contaminants in Lake Superior Using hydrogeologic context and water budgets to evaluate the potential for groundwater contributions to contaminants in Lake Superior
This study presents a synthesis of the hydrogeology in the U.S. Lake Superior watershed and the contribution of groundwater to the water budget of the U.S. Lake Superior basin. Much of the shoreline of Lake Superior in Minnesota and Michigan is composed of hydrogeologic units contributing very little direct groundwater discharge to the lake. Groundwater in watersheds adjacent to the lake...
Authors
Martha G. Nielsen, Sherry Lynn Martin
Updated estimates of water budget components for the Mississippi Embayment Region using a soil-water-balance model, 2000–2020 Updated estimates of water budget components for the Mississippi Embayment Region using a soil-water-balance model, 2000–2020
A Soil-Water-Balance (SWB) model for the Mississippi embayment region in Arkansas, Tennessee, Mississippi, and Louisiana was constructed and calibrated to gain insight into potential recharge patterns for the Mississippi River Valley alluvial aquifer, which has had substantial drawdown under intense pumping stress over the last several decades. An analysis of the net infiltration term...
Authors
Martha G. Nielsen, Stephen, M. Westenbroek
Documentation of a pilot workflow for reanalyzing the U.S. Geological Survey principal aquifers datasets and prototype principal aquifer version 2 dataset for three aquifer systems Documentation of a pilot workflow for reanalyzing the U.S. Geological Survey principal aquifers datasets and prototype principal aquifer version 2 dataset for three aquifer systems
A pilot workflow to refine the principal aquifers of the United States as defined in the Ground Water Atlas of the United States and create a new version of the principal aquifers (referred to as “version 2”) is documented in this report. The workflow incorporates decision points for creating finer scale spatial data for the principal aquifers and refining the original principal aquifer...
Authors
Martha G. Nielsen
Simulation of groundwater flow at the former Badger Army Ammunition Plant, Sauk County, Wisconsin Simulation of groundwater flow at the former Badger Army Ammunition Plant, Sauk County, Wisconsin
To help support remedial efforts at the former Badger Army Ammunition Plant the U.S. Geological Survey built and calibrated a transient groundwater flow model using the Newton Raphson formulation (MODFLOW–NWT) of the U.S. Geological Survey’s modular three-dimensional finite-difference code. The model simulates the groundwater flow system at the site from 1984 to 2020. The former Badger...
Authors
Megan J. Haserodt, Howard W. Reeves, Martha G. Nielsen, Laura A. Schachter, Nicholas T. Corson-Dosch, Daniel T. Feinstein
Initial estimates of net infiltration and irrigation from a soil-water-balance model of the Mississippi Embayment Regional Aquifer Study Area Initial estimates of net infiltration and irrigation from a soil-water-balance model of the Mississippi Embayment Regional Aquifer Study Area
The Mississippi embayment encompasses about 100,000 square miles and covers parts of eight States. In 2016, the U.S. Geological Survey began updating previous work for a part of the embayment known as the Mississippi Alluvial Plain to support informed water use and agricultural policy in the region. Groundwater, water use, economic, and other related models are being combined with field...
Authors
Stephen, M. Westenbroek, Martha G. Nielsen, David E. Ladd
Estimated groundwater withdrawals from principal aquifers in the United States, 2015 Estimated groundwater withdrawals from principal aquifers in the United States, 2015
In 2015, about 84,600 million gallons per day (Mgal/d) of groundwater were withdrawn in the United States for various uses including public supply, self-supplied domestic, industrial, mining, thermoelectric power, aquaculture, livestock, and irrigation. Of this total, about 94 percent (79,200 Mgal/d) was withdrawn from principal aquifers, which are defined as regionally extensive...
Authors
John K. Lovelace, Martha G. Nielsen, Amy L. Read, Chid J. Murphy, Molly A. Maupin
Groundwater recharge estimates for Maine using a Soil-Water-Balance model—25-year average, range, and uncertainty, 1991 to 2015 Groundwater recharge estimates for Maine using a Soil-Water-Balance model—25-year average, range, and uncertainty, 1991 to 2015
To address the lack of information on the spatial and temporal variability of recharge to groundwater systems in Maine, a study was initiated in cooperation with the Maine Geological Survey to use the U.S. Geological Survey Soil-Water-Balance model to evaluate annual average potential recharge across the State over a 25-year period from 1991 to 2015. The Maine Soil-Water-Balance model...
Authors
Martha G. Nielsen, Stephen M. Westenbroek
The Connecticut Streamflow and Sustainable Water Use Estimator—A decision-support tool to estimate water availability at ungaged stream locations in Connecticut The Connecticut Streamflow and Sustainable Water Use Estimator—A decision-support tool to estimate water availability at ungaged stream locations in Connecticut
Freshwater streams in Connecticut are subject to many competing demands, including public water supply; agricultural, commercial, and industrial water use; and ecosystem and habitat needs. In recent years, drought has further stressed Connecticut’s water resources. To sustainably allocate and manage water resources among these competing uses, Federal, State, and local water-resource...
Authors
Sara B. Levin, Scott A. Olson, Martha G. Nielsen, Gregory E. Granato
Groundwater-level trends in the U.S. glacial aquifer system, 1964-2013 Groundwater-level trends in the U.S. glacial aquifer system, 1964-2013
The glacial aquifer system in the United States is a major source of water supply but previous work on historical groundwater trends across the system is lacking. Trends in annual minimum, mean, and maximum groundwater levels for 205 monitoring wells were analyzed across three regions of the system (East, Central, West Central) for four time periods: 1964-2013, 1974-2013, 1984-2013, and...
Authors
Glenn A. Hodgkins, Robert W. Dudley, Martha G. Nielsen, Benjamin Renard, Sharon L. Qi
Simulation of groundwater flow and streamflow depletion in the Branch Brook, Merriland River, and parts of the Mousam River watersheds in southern Maine Simulation of groundwater flow and streamflow depletion in the Branch Brook, Merriland River, and parts of the Mousam River watersheds in southern Maine
Watersheds of three streams, the Mousam River, Branch Brook, and Merriland River in southeastern Maine were investigated from 2010 through 2013 under a cooperative project between the U.S. Geological Survey and the Maine Geological Survey. The Branch Brook watershed previously had been deemed “at risk” by the Maine Geological Survey because of the proportionally large water withdrawals...
Authors
Martha G. Nielsen, Daniel B. Locke
Flow and sorption controls of groundwater arsenic in individual boreholes from bedrock aquifers in central Maine, USA Flow and sorption controls of groundwater arsenic in individual boreholes from bedrock aquifers in central Maine, USA
To understand the hydrogeochemical processes regulating well water arsenic (As) evolution in fractured bedrock aquifers, three domestic wells with [As] up to 478 μg/L are investigated in central Maine. Geophysical logging reveals that fractures near the borehole bottom contribute 70-100% of flow. Borehole and fracture water samples from various depths show significant proportions of As...
Authors
Qiang Yang, Charles W. Culbertson, Martha G. Nielsen, Charles W. Schalk, Carole D. Johnson, Robert G. Marvinney, Martin Stute, Yan Zheng
Changes in nitrogen loading to the Northeast Creek Estuary, Bar Harbor, Maine, 2000 to 2010 Changes in nitrogen loading to the Northeast Creek Estuary, Bar Harbor, Maine, 2000 to 2010
Since 1999, the U.S. Geological Survey and the National Park Service have been monitoring land use and nitrogen loading in a 26.3-square-kilometer (10-square-mile) estuarine watershed at Acadia National Park, Mount Desert Island, Maine. The initial study linking land use and nitrogen loads entering the Northeast Creek estuary was completed in 2000, and findings were used to develop...
Authors
Martha G. Nielsen
Science and Products
New England Water Use
Monthly water use estimates for New England and the rest of the conterminous U.S. are now available for the three largest categories of use in the United States: public supply, crop irrigation, and thermoelectric power generation.
Recharge Estimates for Maine: 25-year Average, Range, and Uncertainty, 1990-2015
The USGS Soil-Water-Balance model (SWB) has been used to estimate potential recharge across the State of Maine. The average and range (minimum and maximum) of annual recharge were estimated for the 25-year period from 1990 to 2015. Datasets of estimated recharge and the modeled uncertainty in the recharge estimates are available for download.
Data for improved understanding of the susceptibility of Lake Superior to threats from groundwater contamination Data for improved understanding of the susceptibility of Lake Superior to threats from groundwater contamination
This data release contains a data compilation and analysis of the hydrogeology in the U.S. portion of the Lake Superior watershed, for the purpose of providing background data for future study and modeling of groundwater and contaminant movement in the watershed. The data support an analysis of groundwater contributions to the water budget of Lake Superior and provide hydrogeologic...
Model archive and output files for net infiltration, runoff, and irrigation water use for the Mississippi Embayment Regional Aquifer System, 2000 to 2020, simulated with the Soil-Water-Balance model Model archive and output files for net infiltration, runoff, and irrigation water use for the Mississippi Embayment Regional Aquifer System, 2000 to 2020, simulated with the Soil-Water-Balance model
This item provides Soil-Water-Balance (SWB) model output and a model archive of water budget simulations for the Mississippi Embayment Regional Aquifer System (MERAS) during the period 2000 to 2020. Gridded daily data (1 kilometer resolution) include net infiltration (groundwater recharge), rejected net infiltration, runoff, irrigation, actual evapotranspiration and gross precipitation...
Prototype updated principal aquifer datasets for three aquifer systems in the Upper Midwest, USA Prototype updated principal aquifer datasets for three aquifer systems in the Upper Midwest, USA
This geospatial dataset represents a prototype of a finer-scale representation of the principal aquifers of the United States, using four original principal aquifers in the Upper Midwest, United States, which were re-analyzed and condensed into three updated principal aquifers. The original principal aquifer definitions and extents were published in the Ground Water Atlas of the United...
Soil-Water-Balance (SWB) model archive used to simulate potential annual recharge for the former Badger Army Ammunition Plant study area, Prairie du Sac, Wisconsin, 1980 to 2020 Soil-Water-Balance (SWB) model archive used to simulate potential annual recharge for the former Badger Army Ammunition Plant study area, Prairie du Sac, Wisconsin, 1980 to 2020
This model archive makes available the U.S. Geological Survey Soil-Water-Balance (SWB) model created in support of a groundwater flow model of the former Badger Army Ammunition Plant in Sauk County, Wisconsin. The SWB model provides initial estimates of potential recharge to the groundwater system in the study area, which are used in a calibrated 3-dimensional MODFLOW (modular finite...
Upper Midwest Water Science Center Groundwater Model Archive Index v1.0 2023 Upper Midwest Water Science Center Groundwater Model Archive Index v1.0 2023
This vector geospatial dataset contains bounding polygons that visualize the domain of archived groundwater flow models published by the Upper Midwest Water Science Center and attributes pertaining to the associated publication (citation, year of publication, authors, report ID, publication URL), model construction details, and a URL for publicly available model archives when available...
OFR 2021-1008 MODEL ARCHIVE: Soil-Water-Balance model developed to simulate net infiltration and irrigation water use for the Mississippi Embayment Regional Aquifer System, 1915 to 2018 OFR 2021-1008 MODEL ARCHIVE: Soil-Water-Balance model developed to simulate net infiltration and irrigation water use for the Mississippi Embayment Regional Aquifer System, 1915 to 2018
This model archive makes available the calibrated Soil-Water-Balance (SWB) model used to simulate potential recharge for the Mississippi Alluvial Aquifer for 1915 to 2018. The model was calibrated using monthly values of evapotranspiration and annual values of runoff and recharge for 19 drainage basins selected from within or nearby the Mississippi Alluvial Aquifer system. The calibrated...
OFR 2021-1008 MODEL OUTPUT: Soil-Water-Balance net infiltration and irrigation water use output datasets for the Mississippi Embayment Regional Aquifer System, 1915 to 2018 OFR 2021-1008 MODEL OUTPUT: Soil-Water-Balance net infiltration and irrigation water use output datasets for the Mississippi Embayment Regional Aquifer System, 1915 to 2018
This data release includes four sets of gridded annual net infiltration (groundwater recharge) and irrigation water use data sets for the Mississippi Embayment Regional Aquifer System (MERAS).Also included are gridded water balance component data sets of precipitation, runoff, actual evapotranspiration, and soil-water storage for 2000 to 2018. The net infiltration, irrigation, runoff...
Estimated Groundwater Withdrawals from Principal Aquifers in the United States--County Level Data for 2015 Estimated Groundwater Withdrawals from Principal Aquifers in the United States--County Level Data for 2015
This dataset contains estimates of water withdrawals from 66 principal aquifers and "other" non-principal aquifers during 2015 for various categories of use in each county or county equivalent in the United States, Puerto Rico, and the U.S. Virgin Islands. The U.S. Geological Survey's (USGS) National Water Use Science Project is responsible for compiling and disseminating the Nation's...
Simulated 25-year potential annual recharge datasets for Maine, 1991-2015 Simulated 25-year potential annual recharge datasets for Maine, 1991-2015
This set of data includes four potential annual recharge grids for the State of Maine that were simulated using the Maine Soil-Water-Balance model for 1991 through 2015. The files include a grid representing the uncertainty in the potential recharge and a grid showing the annual average precipitation from the climate dataset that the simulation is based on. A 25-year simulation of...
Soil-Water-Balance (SWB) model archive used to simulate potential annual recharge in Maine, 1991-2015 Soil-Water-Balance (SWB) model archive used to simulate potential annual recharge in Maine, 1991-2015
This set of data includes four potential annual recharge grids for the State of Maine that were simulated using the Maine Soil-Water-Balance model for 1991 through 2015. The files include a grid representing the uncertainty in the potential recharge and a grid showing the annual average precipitation from the climate dataset that the simulation is based on. A 25-year simulation of...
Data related to the degree of potential human influence near 2228 groundwater wells in the U.S. glacial aquifer system Data related to the degree of potential human influence near 2228 groundwater wells in the U.S. glacial aquifer system
This dataset contains information on the degree of potential human influence near 2228 groundwater wells in the U.S. glacial aquifer system. Data include well identification, name, latitude, longitude, potential-human-influence category, percent urban and crop land use in a 500 meter radius around each well, and measures of county-based groundwater use and irrigation.
Filter Total Items: 27
Using hydrogeologic context and water budgets to evaluate the potential for groundwater contributions to contaminants in Lake Superior Using hydrogeologic context and water budgets to evaluate the potential for groundwater contributions to contaminants in Lake Superior
This study presents a synthesis of the hydrogeology in the U.S. Lake Superior watershed and the contribution of groundwater to the water budget of the U.S. Lake Superior basin. Much of the shoreline of Lake Superior in Minnesota and Michigan is composed of hydrogeologic units contributing very little direct groundwater discharge to the lake. Groundwater in watersheds adjacent to the lake...
Authors
Martha G. Nielsen, Sherry Lynn Martin
Updated estimates of water budget components for the Mississippi Embayment Region using a soil-water-balance model, 2000–2020 Updated estimates of water budget components for the Mississippi Embayment Region using a soil-water-balance model, 2000–2020
A Soil-Water-Balance (SWB) model for the Mississippi embayment region in Arkansas, Tennessee, Mississippi, and Louisiana was constructed and calibrated to gain insight into potential recharge patterns for the Mississippi River Valley alluvial aquifer, which has had substantial drawdown under intense pumping stress over the last several decades. An analysis of the net infiltration term...
Authors
Martha G. Nielsen, Stephen, M. Westenbroek
Documentation of a pilot workflow for reanalyzing the U.S. Geological Survey principal aquifers datasets and prototype principal aquifer version 2 dataset for three aquifer systems Documentation of a pilot workflow for reanalyzing the U.S. Geological Survey principal aquifers datasets and prototype principal aquifer version 2 dataset for three aquifer systems
A pilot workflow to refine the principal aquifers of the United States as defined in the Ground Water Atlas of the United States and create a new version of the principal aquifers (referred to as “version 2”) is documented in this report. The workflow incorporates decision points for creating finer scale spatial data for the principal aquifers and refining the original principal aquifer...
Authors
Martha G. Nielsen
Simulation of groundwater flow at the former Badger Army Ammunition Plant, Sauk County, Wisconsin Simulation of groundwater flow at the former Badger Army Ammunition Plant, Sauk County, Wisconsin
To help support remedial efforts at the former Badger Army Ammunition Plant the U.S. Geological Survey built and calibrated a transient groundwater flow model using the Newton Raphson formulation (MODFLOW–NWT) of the U.S. Geological Survey’s modular three-dimensional finite-difference code. The model simulates the groundwater flow system at the site from 1984 to 2020. The former Badger...
Authors
Megan J. Haserodt, Howard W. Reeves, Martha G. Nielsen, Laura A. Schachter, Nicholas T. Corson-Dosch, Daniel T. Feinstein
Initial estimates of net infiltration and irrigation from a soil-water-balance model of the Mississippi Embayment Regional Aquifer Study Area Initial estimates of net infiltration and irrigation from a soil-water-balance model of the Mississippi Embayment Regional Aquifer Study Area
The Mississippi embayment encompasses about 100,000 square miles and covers parts of eight States. In 2016, the U.S. Geological Survey began updating previous work for a part of the embayment known as the Mississippi Alluvial Plain to support informed water use and agricultural policy in the region. Groundwater, water use, economic, and other related models are being combined with field...
Authors
Stephen, M. Westenbroek, Martha G. Nielsen, David E. Ladd
Estimated groundwater withdrawals from principal aquifers in the United States, 2015 Estimated groundwater withdrawals from principal aquifers in the United States, 2015
In 2015, about 84,600 million gallons per day (Mgal/d) of groundwater were withdrawn in the United States for various uses including public supply, self-supplied domestic, industrial, mining, thermoelectric power, aquaculture, livestock, and irrigation. Of this total, about 94 percent (79,200 Mgal/d) was withdrawn from principal aquifers, which are defined as regionally extensive...
Authors
John K. Lovelace, Martha G. Nielsen, Amy L. Read, Chid J. Murphy, Molly A. Maupin
Groundwater recharge estimates for Maine using a Soil-Water-Balance model—25-year average, range, and uncertainty, 1991 to 2015 Groundwater recharge estimates for Maine using a Soil-Water-Balance model—25-year average, range, and uncertainty, 1991 to 2015
To address the lack of information on the spatial and temporal variability of recharge to groundwater systems in Maine, a study was initiated in cooperation with the Maine Geological Survey to use the U.S. Geological Survey Soil-Water-Balance model to evaluate annual average potential recharge across the State over a 25-year period from 1991 to 2015. The Maine Soil-Water-Balance model...
Authors
Martha G. Nielsen, Stephen M. Westenbroek
The Connecticut Streamflow and Sustainable Water Use Estimator—A decision-support tool to estimate water availability at ungaged stream locations in Connecticut The Connecticut Streamflow and Sustainable Water Use Estimator—A decision-support tool to estimate water availability at ungaged stream locations in Connecticut
Freshwater streams in Connecticut are subject to many competing demands, including public water supply; agricultural, commercial, and industrial water use; and ecosystem and habitat needs. In recent years, drought has further stressed Connecticut’s water resources. To sustainably allocate and manage water resources among these competing uses, Federal, State, and local water-resource...
Authors
Sara B. Levin, Scott A. Olson, Martha G. Nielsen, Gregory E. Granato
Groundwater-level trends in the U.S. glacial aquifer system, 1964-2013 Groundwater-level trends in the U.S. glacial aquifer system, 1964-2013
The glacial aquifer system in the United States is a major source of water supply but previous work on historical groundwater trends across the system is lacking. Trends in annual minimum, mean, and maximum groundwater levels for 205 monitoring wells were analyzed across three regions of the system (East, Central, West Central) for four time periods: 1964-2013, 1974-2013, 1984-2013, and...
Authors
Glenn A. Hodgkins, Robert W. Dudley, Martha G. Nielsen, Benjamin Renard, Sharon L. Qi
Simulation of groundwater flow and streamflow depletion in the Branch Brook, Merriland River, and parts of the Mousam River watersheds in southern Maine Simulation of groundwater flow and streamflow depletion in the Branch Brook, Merriland River, and parts of the Mousam River watersheds in southern Maine
Watersheds of three streams, the Mousam River, Branch Brook, and Merriland River in southeastern Maine were investigated from 2010 through 2013 under a cooperative project between the U.S. Geological Survey and the Maine Geological Survey. The Branch Brook watershed previously had been deemed “at risk” by the Maine Geological Survey because of the proportionally large water withdrawals...
Authors
Martha G. Nielsen, Daniel B. Locke
Flow and sorption controls of groundwater arsenic in individual boreholes from bedrock aquifers in central Maine, USA Flow and sorption controls of groundwater arsenic in individual boreholes from bedrock aquifers in central Maine, USA
To understand the hydrogeochemical processes regulating well water arsenic (As) evolution in fractured bedrock aquifers, three domestic wells with [As] up to 478 μg/L are investigated in central Maine. Geophysical logging reveals that fractures near the borehole bottom contribute 70-100% of flow. Borehole and fracture water samples from various depths show significant proportions of As...
Authors
Qiang Yang, Charles W. Culbertson, Martha G. Nielsen, Charles W. Schalk, Carole D. Johnson, Robert G. Marvinney, Martin Stute, Yan Zheng
Changes in nitrogen loading to the Northeast Creek Estuary, Bar Harbor, Maine, 2000 to 2010 Changes in nitrogen loading to the Northeast Creek Estuary, Bar Harbor, Maine, 2000 to 2010
Since 1999, the U.S. Geological Survey and the National Park Service have been monitoring land use and nitrogen loading in a 26.3-square-kilometer (10-square-mile) estuarine watershed at Acadia National Park, Mount Desert Island, Maine. The initial study linking land use and nitrogen loads entering the Northeast Creek estuary was completed in 2000, and findings were used to develop...
Authors
Martha G. Nielsen