Stephen Westenbroek is a Hydrologist with the Upper Midwest Water Science Center.
Professional Experience
2003-present – Hydrologist, USGS Water Resources Division, Wisconsin Water Science Center
1999 to 2003 – Water resources engineer, Wisconsin Department of Natural Resources, Milwaukee, WI
1996 to 1999 – Water resources engineer, Baird & Associates, Madison, WI
1990 to 1996 – Contaminated sediments project manager, Wisconsin Department of Natural Resources, Madison, WI
1988 to 1990 – Water quality modeler - Wisconsin Department of Natural Resources, Madison, WI
Education and Certifications
M.S. in Water Resources Management, University of Wisconsin-Madison, 1995 Water Resources - Management Practicum: Water Resources of the Bad River Reservation
B.S. in Civil Engineering, University of Michigan, 1988
Science and Products
Filter Total Items: 27
Simulation of monthly mean and monthly base flow of streamflow using random forests for the Mississippi River Alluvial Plain, 1901 to 2018
Improved simulations of streamflow and base flow for selected sites within and adjacent to the Mississippi River Alluvial Plain area are important for modeling groundwater flow because surface-water flows have a substantial effect on groundwater levels. One method for simulating streamflow and base flow, random forest (RF) models, was developed from the data at gaged sites and, in turn, was used t
Authors
Benjamin J. Dietsch, William H. Asquith, Brian K. Breaker, Stephen M. Westenbroek, Wade H. Kress
Simulation of regional groundwater flow and groundwater/lake interactions in the Central Sands, Wisconsin
A multiscale, multiprocess modeling approach was applied to the Wisconsin Central Sands region in central Wisconsin to quantify the connections between the groundwater system, land use, and lake levels in three seepage lakes in Waushara County, Wisconsin: Long and Plainfield (The Plainfield Tunnel Channel Lakes), and Pleasant Lakes. A regional groundwater-flow model, the Newton Raphson formulation
Authors
Michael N. Fienen, Megan J. Haserodt, Andrew T. Leaf, Stephen M. Westenbroek
Appendix C: Central sands lakes study technical report: Modeling documentation
This report provides the necessary documentation of the numerical models developed for the Central Sands Lake study in central Wisconsin and will be included as a technical appendix in the report to the Wisconsin State Legislature by the Wisconsin Department of Natural Resources (WDNR) in response to 2017 Wisconsin Act 10. This legislation directed WDNR to determine whether existing and potential
Authors
Michael N. Fienen, Megan J. Haserodt, Andrew T. Leaf, Stephen, M. Westenbroek
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 surveys an
Authors
Stephen, M. Westenbroek, Martha G. Nielsen, David E. Ladd
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 was calibrat
Authors
Martha G. Nielsen, Stephen M. Westenbroek
Characterization and occurrence of confined and unconfined aquifers in Quaternary sediments in the glaciated conterminous United States
The glacial aquifer system, which is a collection of aquifers within Quaternary sediments in the glaciated conterminous United States, is a principal aquifer that supplies groundwater that serves about 42 million people and accounts for about 5 percent of the Nation’s drinking water. This aquifer system (the area of maximum glacial advance) underlies parts of 25 States and covers 1.87×106 square k
Authors
Richard M. Yager, Leon J. Kauffman, David R. Soller, Adel E. Haj, Paul M. Heisig, Cheryl A. Buchwald, Stephen, M. Westenbroek, James E. Reddy
SWB Version 2.0—A soil-water-balance code for estimating net infiltration and other water-budget components
The U.S. Geological Survey’s Soil-Water-Balance (SWB) code was developed as a tool to estimate distribution and timing of net infiltration out of the root zone by means of an approach that uses readily available data and minimizes user effort required to begin a SWB application. SWB calculates other components of the water balance, including soil moisture, reference and actual evapotranspiration,
Authors
Stephen M. Westenbroek, John A. Engott, Victor A. Kelson, Randall J. Hunt
Simulation of potential groundwater recharge for the glacial aquifer system east of the Rocky Mountains, 1980–2011, using the Soil-Water-Balance Model
An understanding of the spatial and temporal extent of groundwater recharge is critical for many types of hydrologic assessments involving water quality, contaminant transport, ecosystem health, and sustainable use of groundwater. Annual potential groundwater recharge was simulated at a 1-kilometer resolution with the Soil-Water-Balance (SWB) model for the glacial aquifer system east of the Rocky
Authors
Jared J. Trost, Jason L. Roth, Stephen M. Westenbroek, Howard W. Reeves
Updated polychlorinated biphenyl mass budget for Lake Michigan
This study revisits and updates the Lake Michigan Mass Balance Project (LMMBP) for polychlorinated biphenyls (PCBs) that was conducted in 1994–1995. This work uses recent concentrations of PCBs in tributary and open lake water, air, and sediment to calculate an updated mass budget. Five of the 11 LMMBP tributaries were revisited in 2015. In these five tributaries, the geometric mean concentrations
Authors
Jiehong Guo, Kevin Romanak, Stephen M. Westenbroek, An Li, Russell Kreis, Ronald A. Hites, Marta Venier
Current-use flame retardants in the water of Lake Michigan tributaries
In this study, we measured the concentrations of 65 flame retardants in water samples from five Lake Michigan tributaries. These flame retardants included organophosphate esters (OPEs), brominated flame retardants (BFRs), and Dechlorane-related compounds. A total of 59 samples, including both the particulate and the dissolved phases, were collected from the Grand, Kalamazoo, Saint Joseph, and Lowe
Authors
Jiehong Guo, Kevin Romanak, Stephen M. Westenbroek, Ronald A. Hites, Marta Venier
Groundwater flow model for the Little Plover River basin in Wisconsin’s Central Sands
The Little Plover River is a groundwater-fed stream in the sand plains region of central Wisconsin. In this region, sandy sediment deposited during or soon after the last glaciation forms an important unconfined sand and gravel aquifer. This aquifer supplies water for numerous high-capacity irrigation, municipal, and industrial wells that support a thriving agricultural industry. In recent years t
Authors
Ken Bradbury, Michael N. Fienen, Maribeth Kniffin, Jacob Krause, Stephen M. Westenbroek, Andrew T. Leaf, Paul M. Barlow
Identification of Marbon in the Indiana Harbor and Ship Canal
Marbon is isomeric with Dechlorane Plus (DP). Both are produced by the Diels−
Alder condensation of hexachlorocyclopentadiene with cyclic dienes, and both have elemental
compositions of C18H12Cl12. Dechlorane Plus is commonly found in the environment throughout
the world, but Marbon has, so far, only been detected at low levels in one sediment core collected
near the mouth of the Niagara River in
Authors
Jiehong Guo, Marta Venier, Kevin Romanak, Stephen M. Westenbroek, Ronald A. Hites
TSPROC: a general time-series processor to assist in model calibration and result summarization
TSPROC (Time Series PROCessor) is a software package designed to assist in the calibration of models by editing and distilling time series datasets into more meaningful observations to be used in the optimization objective function. The software performs calculations on time-series data associated with surface-water models, including calculation of flow volumes, transformation by means of basic...
Soil-Water-Balance (SWB): A modified Thornthwaite-Mather model for estimating groundwater recharge
The Soil-Water-Balance (SWB) model has been developed to allow estimates of potential recharge to be made quickly and easily. The code calculates components of the water balance at a daily time-step by means of a modified version of the Thornthwaite-Mather soil-moisture-balance approach.
MODFLOW-NWT model used to assess historical and future trends in groundwater availability in the Trinity River alluvium aquifer, Texas
The U.S. Geological Survey, in cooperation with the Trinity River Authority, the Tarrant Regional Water District, the City of Dallas, and the North Texas Municipal Water District, constructed a finite-difference numerical groundwater-flow model of the Trinity River alluvium aquifer using MODFLOW with the Newton formulation solver (MODFLOW-NWT). This model, along with a surface water model and an a
Input data, trained model data, and model outputs for predicting streamflow and base flow for the Mississippi Embayment Regional Study Area using a random forest model
This data release contains datasets developed for the purpose of training and applying random forest models to the Mississippi Embayment Regional Study Area. The random forest models are designed to predict total stream flow and baseflow as a function of a combination of watershed characteristics and monthly weather data. These datasets are associated with a report (SIR 2022-xxxx) and code contain
Soil-Water-Balance model developed to simulate net infiltration, irrigation water requirements, and other water budget components in support of the Central Sands Lakes Study, Wisconsin
This model archive provides input and output for Soil-Water-Balance (SWB) models developed for the Central Sands Lake study in central Wisconsin; this archive supplements the technical appendix in a report to the Wisconsin State Legislature written by the Wisconsin Department of Natural Resources (WDNR) in response to 2017 Wisconsin Act 10. This legislation directed DNR to determine whether existi
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 SWB model
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, actual evapo
Digital products from a hydrogeologic framework for Quaternary sediments within the glaciated conterminous United States
This data release is a compilation of the digital products from a hydrogeologic framework of the glaciated conterminous United States that were constructed to portray sediment and aquifer characteristics within this area. These digital products are described in Yager, R.M., Kauffman, L.J., Soller, D.R., Haj, A.E., Heisig, P.M., Buchwald, C.A., Westenbroek, S.M., and Reddy, J.E., 2018, Characteriza
FishVis, predicted occurrence and vulnerability for 13 fish species for current (1961 - 1990) and future (2046 - 2100) climate conditions in Great Lakes streams.
Climate change is expected to alter the distributions and community composition of stream fishes in the Great Lakes region in the 21st century, in part as a result of altered hydrological systems (stream temperature, streamflow, and habitat). Resource managers need information and tools to understand where fish species and stream habitats are expected to change under future conditions. Fish sample
FishVis Mapper
The FishVis Mapper is the product of an Upper Midwest and Great Lakes LCC project, “A Regional Decision Support Tool for Identifying Vulnerabilities of Riverine Habitat and Fishes to Climate Change” that developed an approach for predicting fish species occurrence under current climate conditions and project how fish species occurrence may change under future climate conditions.
mapRandomForest---Monthly flow estimation in the Mississippi Alluvial Plain by means of Random Forest Modeling
The code included in this package, when combined with data retrieved from an associated ScienceBase archive, is designed to allow for reasonable monthly total and baseflow volumes to be estimated at arbitrary locations within the Mississippi Embayment as part of the Mississippi Alluvial Plain (MAP) Project. The resulting surface water volume estimates were used as inputs to associated groundwater
Soil-Water-Balance (SWB) for estimating groundwater recharge
The Soil-Water-Balance (SWB) model has been developed to allow estimates of potential recharge to be made quickly and easily. The code calculates components of the water balance at a daily time-step by means of a modified version of the Thornthwaite-Mather soil-moisture-balance approach.
TSPROC: a general time-series processor to assist in model calibration and result summarization
TSPROC (Time Series PROCessor) is a software package designed to assist in the calibration of models by editing and distilling time series datasets into more meaningful observations to be used in the optimization objective function. TSPROC uses a simple scripting language to process and analyze time series.
Science and Products
- Publications
Filter Total Items: 27
Simulation of monthly mean and monthly base flow of streamflow using random forests for the Mississippi River Alluvial Plain, 1901 to 2018
Improved simulations of streamflow and base flow for selected sites within and adjacent to the Mississippi River Alluvial Plain area are important for modeling groundwater flow because surface-water flows have a substantial effect on groundwater levels. One method for simulating streamflow and base flow, random forest (RF) models, was developed from the data at gaged sites and, in turn, was used tAuthorsBenjamin J. Dietsch, William H. Asquith, Brian K. Breaker, Stephen M. Westenbroek, Wade H. KressSimulation of regional groundwater flow and groundwater/lake interactions in the Central Sands, Wisconsin
A multiscale, multiprocess modeling approach was applied to the Wisconsin Central Sands region in central Wisconsin to quantify the connections between the groundwater system, land use, and lake levels in three seepage lakes in Waushara County, Wisconsin: Long and Plainfield (The Plainfield Tunnel Channel Lakes), and Pleasant Lakes. A regional groundwater-flow model, the Newton Raphson formulationAuthorsMichael N. Fienen, Megan J. Haserodt, Andrew T. Leaf, Stephen M. WestenbroekAppendix C: Central sands lakes study technical report: Modeling documentation
This report provides the necessary documentation of the numerical models developed for the Central Sands Lake study in central Wisconsin and will be included as a technical appendix in the report to the Wisconsin State Legislature by the Wisconsin Department of Natural Resources (WDNR) in response to 2017 Wisconsin Act 10. This legislation directed WDNR to determine whether existing and potentialAuthorsMichael N. Fienen, Megan J. Haserodt, Andrew T. Leaf, Stephen, M. WestenbroekInitial 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 surveys anAuthorsStephen, M. Westenbroek, Martha G. Nielsen, David E. LaddGroundwater 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 was calibratAuthorsMartha G. Nielsen, Stephen M. WestenbroekCharacterization and occurrence of confined and unconfined aquifers in Quaternary sediments in the glaciated conterminous United States
The glacial aquifer system, which is a collection of aquifers within Quaternary sediments in the glaciated conterminous United States, is a principal aquifer that supplies groundwater that serves about 42 million people and accounts for about 5 percent of the Nation’s drinking water. This aquifer system (the area of maximum glacial advance) underlies parts of 25 States and covers 1.87×106 square kAuthorsRichard M. Yager, Leon J. Kauffman, David R. Soller, Adel E. Haj, Paul M. Heisig, Cheryl A. Buchwald, Stephen, M. Westenbroek, James E. ReddySWB Version 2.0—A soil-water-balance code for estimating net infiltration and other water-budget components
The U.S. Geological Survey’s Soil-Water-Balance (SWB) code was developed as a tool to estimate distribution and timing of net infiltration out of the root zone by means of an approach that uses readily available data and minimizes user effort required to begin a SWB application. SWB calculates other components of the water balance, including soil moisture, reference and actual evapotranspiration,AuthorsStephen M. Westenbroek, John A. Engott, Victor A. Kelson, Randall J. HuntSimulation of potential groundwater recharge for the glacial aquifer system east of the Rocky Mountains, 1980–2011, using the Soil-Water-Balance Model
An understanding of the spatial and temporal extent of groundwater recharge is critical for many types of hydrologic assessments involving water quality, contaminant transport, ecosystem health, and sustainable use of groundwater. Annual potential groundwater recharge was simulated at a 1-kilometer resolution with the Soil-Water-Balance (SWB) model for the glacial aquifer system east of the RockyAuthorsJared J. Trost, Jason L. Roth, Stephen M. Westenbroek, Howard W. ReevesUpdated polychlorinated biphenyl mass budget for Lake Michigan
This study revisits and updates the Lake Michigan Mass Balance Project (LMMBP) for polychlorinated biphenyls (PCBs) that was conducted in 1994–1995. This work uses recent concentrations of PCBs in tributary and open lake water, air, and sediment to calculate an updated mass budget. Five of the 11 LMMBP tributaries were revisited in 2015. In these five tributaries, the geometric mean concentrationsAuthorsJiehong Guo, Kevin Romanak, Stephen M. Westenbroek, An Li, Russell Kreis, Ronald A. Hites, Marta VenierCurrent-use flame retardants in the water of Lake Michigan tributaries
In this study, we measured the concentrations of 65 flame retardants in water samples from five Lake Michigan tributaries. These flame retardants included organophosphate esters (OPEs), brominated flame retardants (BFRs), and Dechlorane-related compounds. A total of 59 samples, including both the particulate and the dissolved phases, were collected from the Grand, Kalamazoo, Saint Joseph, and LoweAuthorsJiehong Guo, Kevin Romanak, Stephen M. Westenbroek, Ronald A. Hites, Marta VenierGroundwater flow model for the Little Plover River basin in Wisconsin’s Central Sands
The Little Plover River is a groundwater-fed stream in the sand plains region of central Wisconsin. In this region, sandy sediment deposited during or soon after the last glaciation forms an important unconfined sand and gravel aquifer. This aquifer supplies water for numerous high-capacity irrigation, municipal, and industrial wells that support a thriving agricultural industry. In recent years tAuthorsKen Bradbury, Michael N. Fienen, Maribeth Kniffin, Jacob Krause, Stephen M. Westenbroek, Andrew T. Leaf, Paul M. BarlowIdentification of Marbon in the Indiana Harbor and Ship Canal
Marbon is isomeric with Dechlorane Plus (DP). Both are produced by the Diels− Alder condensation of hexachlorocyclopentadiene with cyclic dienes, and both have elemental compositions of C18H12Cl12. Dechlorane Plus is commonly found in the environment throughout the world, but Marbon has, so far, only been detected at low levels in one sediment core collected near the mouth of the Niagara River inAuthorsJiehong Guo, Marta Venier, Kevin Romanak, Stephen M. Westenbroek, Ronald A. Hites - Science
TSPROC: a general time-series processor to assist in model calibration and result summarization
TSPROC (Time Series PROCessor) is a software package designed to assist in the calibration of models by editing and distilling time series datasets into more meaningful observations to be used in the optimization objective function. The software performs calculations on time-series data associated with surface-water models, including calculation of flow volumes, transformation by means of basic...Soil-Water-Balance (SWB): A modified Thornthwaite-Mather model for estimating groundwater recharge
The Soil-Water-Balance (SWB) model has been developed to allow estimates of potential recharge to be made quickly and easily. The code calculates components of the water balance at a daily time-step by means of a modified version of the Thornthwaite-Mather soil-moisture-balance approach. - Data
MODFLOW-NWT model used to assess historical and future trends in groundwater availability in the Trinity River alluvium aquifer, Texas
The U.S. Geological Survey, in cooperation with the Trinity River Authority, the Tarrant Regional Water District, the City of Dallas, and the North Texas Municipal Water District, constructed a finite-difference numerical groundwater-flow model of the Trinity River alluvium aquifer using MODFLOW with the Newton formulation solver (MODFLOW-NWT). This model, along with a surface water model and an aInput data, trained model data, and model outputs for predicting streamflow and base flow for the Mississippi Embayment Regional Study Area using a random forest model
This data release contains datasets developed for the purpose of training and applying random forest models to the Mississippi Embayment Regional Study Area. The random forest models are designed to predict total stream flow and baseflow as a function of a combination of watershed characteristics and monthly weather data. These datasets are associated with a report (SIR 2022-xxxx) and code containSoil-Water-Balance model developed to simulate net infiltration, irrigation water requirements, and other water budget components in support of the Central Sands Lakes Study, Wisconsin
This model archive provides input and output for Soil-Water-Balance (SWB) models developed for the Central Sands Lake study in central Wisconsin; this archive supplements the technical appendix in a report to the Wisconsin State Legislature written by the Wisconsin Department of Natural Resources (WDNR) in response to 2017 Wisconsin Act 10. This legislation directed DNR to determine whether existiOFR 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 SWB modelOFR 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, actual evapoDigital products from a hydrogeologic framework for Quaternary sediments within the glaciated conterminous United States
This data release is a compilation of the digital products from a hydrogeologic framework of the glaciated conterminous United States that were constructed to portray sediment and aquifer characteristics within this area. These digital products are described in Yager, R.M., Kauffman, L.J., Soller, D.R., Haj, A.E., Heisig, P.M., Buchwald, C.A., Westenbroek, S.M., and Reddy, J.E., 2018, CharacterizaFishVis, predicted occurrence and vulnerability for 13 fish species for current (1961 - 1990) and future (2046 - 2100) climate conditions in Great Lakes streams.
Climate change is expected to alter the distributions and community composition of stream fishes in the Great Lakes region in the 21st century, in part as a result of altered hydrological systems (stream temperature, streamflow, and habitat). Resource managers need information and tools to understand where fish species and stream habitats are expected to change under future conditions. Fish sample - Web Tools
FishVis Mapper
The FishVis Mapper is the product of an Upper Midwest and Great Lakes LCC project, “A Regional Decision Support Tool for Identifying Vulnerabilities of Riverine Habitat and Fishes to Climate Change” that developed an approach for predicting fish species occurrence under current climate conditions and project how fish species occurrence may change under future climate conditions.
- Software
mapRandomForest---Monthly flow estimation in the Mississippi Alluvial Plain by means of Random Forest Modeling
The code included in this package, when combined with data retrieved from an associated ScienceBase archive, is designed to allow for reasonable monthly total and baseflow volumes to be estimated at arbitrary locations within the Mississippi Embayment as part of the Mississippi Alluvial Plain (MAP) Project. The resulting surface water volume estimates were used as inputs to associated groundwaterSoil-Water-Balance (SWB) for estimating groundwater recharge
The Soil-Water-Balance (SWB) model has been developed to allow estimates of potential recharge to be made quickly and easily. The code calculates components of the water balance at a daily time-step by means of a modified version of the Thornthwaite-Mather soil-moisture-balance approach.
TSPROC: a general time-series processor to assist in model calibration and result summarization
TSPROC (Time Series PROCessor) is a software package designed to assist in the calibration of models by editing and distilling time series datasets into more meaningful observations to be used in the optimization objective function. TSPROC uses a simple scripting language to process and analyze time series.