Diagram of the process of water use from source (surface water, groundwater, reuse water) through transmission, utility reservoir, water treatment, distribution, and withdrawal for industry, residential, and commercial.
Richard G Niswonger
Richard Niswonger is a Research Hydrologist with the USGS Water Resources Mission Area.
We study local and regional water resources to aid water management decisions by developing software and constructing models that simulate both natural hydrologic processes and human water usage.
In my current role as the national water use research manager, I lead teams in the development of nationally consistent models with three key features: automated data retrieval, monthly simulation at the USGS 12-digit Watershed Boundary Dataset (HUC12) resolution, and periodic updates for current and forecasted results. These models help identify data gaps, enhance data collection, and refine water use predictions. They facilitate frequent reporting, synthesis, and interpretation of data that support communities making informed water resources decisions.
Science and Products
Water for the Seasons
Water for the Seasons (WftS) is a four year study funded by the National Science Foundation and the U.S. Department of Agriculture. WtfS uses the Truckee-Carson River System (TCRS) as a pilot study to learn how to best link science with decision-making in snow-fed arid-land river systems. By working collaboratively with stakeholders, WftS aims to create a model for improving community climate...
Public supply water use reanalysis for the 2000-2020 period by HUC12, month, and year for the conterminous United States (ver. 2.0, August 2024)
The U.S. Geological Survey is developing national water-use models to support water resources management in the United States. Model benefits include a nationally consistent estimation approach, greater temporal and spatial resolution of estimates, efficient and automated updates of results, and capabilities to forecast water use into the future and assess model uncertainty. The term...
Thermoelectric-power condenser duty estimates by month and cooling type for use to calculate water use by power plant for the 2008-2020 reanalysis period for the conterminous United States
The U.S. Geological Survey (USGS) developed models to estimate the amount of water that is withdrawn and consumed by thermoelectric power plants (Diehl and others, 2013; Diehl and Harris, 2014; Harris and Diehl, 2019). The thermoelectric water use models are based on linked heat-and-water budgets that are constrained by power plant generation and cooling system technologies, the amount...
Thermoelectric-power water use reanalysis for the 2008-2020 period by power plant, month, and year for the conterminous United States
Previous work by the U.S. Geological Survey (USGS) developed models to estimate the amount of water that is withdrawn and consumed by thermoelectric power plants (Diehl and others, 2013; Diehl and Harris, 2014; Harris and Diehl, 2019 [full citations listed in srcinfo of the metadata file]). This data release presents a historical reanalysis of thermoelectric water use from 2008 to 2020...
Monthly crop irrigation withdrawals and efficiencies by HUC12 watershed for years 2000-2020 within the conterminous United States (ver. 2.0, September 2024)
The USGS has published United States water-use data every five years since 1950. To increase the temporal and spatial availability of water use estimates using nationally consistent methods, the USGS is developing national water-use models for each major water-use category. This data release publishes crop irrigation withdrawals for the conterminous United States (CONUS) that are...
Irrigation water use reanalysis for the 2000-20 period by HUC12, month, and year for the conterminous United States (ver. 2.0, September 2024)
This data release provides a monthly irrigation water use reanalysis for the period 2000-20 for all USGS Watershed Boundary Dataset of Subwatersheds (HUC12) in the conterminous United States (CONUS). Results include reference evapotranspiration (ETo), actual evapotranspiration (ETa), irrigated areas, consumptive use, and effective precipitation for each HUC12. ETo and ETa were estimated...
MODFLOW-NWT model used to simulate Potential Effects of Changes in Water Use in the Middle Carson River Basin for Eagle, Dayton, and Churchill Valleys, West-Central, Nevada
A three-dimensional MODFLOW-NWT groundwater flow model was developed to evaluate the impacts of alternative water management scenarios on the groundwater resources of Eagle, Dayton, and Churchill Valleys, Nevada. In addition, the resulting impact on flows in the Carson River and Lahontan Reservoir are also evaluated. During the economic boom that occurred from 2004-2006 in northwestern...
GSFLOW and MODSIM-GSFLOW model used to evaluate the potential effects of increased temperature on the Carson Valley watershed and agricultural system in eastern California and western Nevada
The USGS developed an integrated river operations-groundwater model using GSFLOW and MODSIM GSFLOW to simulate streamflow derived from snowmelt, the distribution of surface water based on the existing prior appropriations water doctrine, supplemental pumping in response to surface water shortfalls, and the resulting surface water-groundwater interactions in the Carson Valley in...
Nitrogen and phosphorus, other water quality parameters, and sediment temperature data for Incline Creek and Marlette Creek stream-lake interface, Lake Tahoe, Nevada, September 2013
This data set contains the following parameters: sediment and water temperature, dissolved nitrate plus nitrite dissolved, ammonium, total Kjeldahl nitrogen, soluble orthophosphate, dissolved phosphorus, total phosphorus, and dissolved organic carbon.
Water Use Diagram
Diagram of the process of water use from source (surface water, groundwater, reuse water) through transmission, utility reservoir, water treatment, distribution, and withdrawal for industry, residential, and commercial.
Filter Total Items: 57
Automating physics-based models to estimate thermoelectric-power water use
Thermoelectric (TE) power plants withdraw more water than any other sector of water use in the United States and consume water at rates that can be significant especially in water-stressed regions. Historical TE water-use data have been inconsistent, incomplete, or discrepant, resulting in an increased research focus on improving the accuracy and availability of TE water-use data using...
Authors
Melissa A. Harris, Timothy H. Diehl, Lillian Gorman Sanisaca, Amy E. Galanter, Melissa Lombard, Kenneth Skinner, Catherine A. Chamberlin, Brendan A. McCarthy, Richard G. Niswonger, Jana Stewart, Kristen J. Valseth
Next generation public supply water withdrawal estimation for the conterminous United States using machine learning and operational frameworks
Estimation of human water withdrawals is more important now than ever due to uncertain water supplies, population growth, and climate change. Fourteen percent of the total water withdrawal in the United States is used for public supply, typically including deliveries to domestic, commercial, and occasionally including industrial, irrigation, and thermoelectric water withdrawal. Stewards...
Authors
Ayman H. Alzraiee, Richard G. Niswonger, Carol L. Luukkonen, Joshua Larsen, Donald Martin, Deidre Mary Herbert, Cheryl A. Buchwald, Cheryl A. Dieter, Lisa D. Miller, Jana Stewart, Natalie Houston, Scott R. Paulinski, Kristen Valseth
A probabilistic approach to training machine learning models using noisy data
Machine learning (ML) models are increasingly popular in environmental and hydrologic modeling, but they typically contain uncertainties resulting from noisy data (erroneous or outlier data). This paper presents a novel probabilistic approach that combines ML and Markov Chain Monte Carlo simulation to (1) detect and underweight likely noisy data, (2) develop an approach capable of...
Authors
Ayman H. Alzraiee, Richard G. Niswonger
Development and evaluation of public-supply community water service area boundaries for the conterminous United States
The water service area dataset, derived from the National Boundary Dataset for public-supply water systems in the United States, offers a detailed resolution surpassing county-level assessments, emphasizing water-centric land use. Crucial for linking populations and infrastructure to system withdrawals, it supports the creation of a national public-supply water-use model, enhancing...
Authors
Cheryl A. Buchwald, Natalie Houston, Jana Stewart, Ayman H. Alzraiee, Richard G. Niswonger, Joshua Larsen
Declining groundwater storage expected to amplify mountain streamflow reductions in a warmer world
Groundwater interactions with mountain streams are often simplified in model projections, potentially leading to inaccurate estimates of streamflow response to climate change. Here, using a high-resolution, integrated hydrological model extending 400 m into the subsurface, we find groundwater an important and stable source of historical streamflow in a mountainous watershed of the...
Authors
Rosemary W.H. Carroll, Richard G. Niswonger, Craig Ulrich, Charuleka Varadharajan, Erica Siirila-Woodburn, Kenneth H. Williams
An agricultural package for MODFLOW 6 using the Application Programming Interface
An agricultural water use package has been developed for MODFLOW 6 using the MODFLOW Application Programming Interface (API). The MODFLOW API Agricultural Water Use Package (API-Ag) was based on the approach to simulate irrigation demand in the MODFLOW-NWT and GSFLOW Agricultural Water Use (AG) Package. The API-Ag Package differs from the previous approach by implementing new features...
Authors
Joshua Larsen, Christian D. Langevin, Joseph D. Hughes, Richard G. Niswonger
Assessing potential effects of changes in water use in the middle Carson River Basin with a numerical groundwater-flow model, Eagle, Dayton, and Churchill Valleys, west-central Nevada
During the economic boom of the mid part of the first decade of the 2000s in northwestern Nevada, municipal and housing growth increased use of the water resources of this semi-arid region. In 2008, when the economy slowed, new housing development stopped, and immediate pressure on groundwater resources abated. The U.S. Geological Survey, in cooperation with the Bureau of Reclamation...
Authors
Eric D. Morway, Susan G. Buto, Richard G. Niswonger, Justin L. Huntington
Can hydrological models benefit from using global soil moisture, evapotranspiration, and runoff products as calibration targets?
Hydrological models are usually calibrated to in-situ streamflow observations with reasonably long and uninterrupted records. This is challenging for poorly gage or ungaged basins where such information is not available. Even for gaged basins, the single-objective calibration to gaged streamflow cannot guarantee reliable forecasts because, as has been documented elsewhere, the inverse...
Authors
Yiwen Mei, Juliane Mai, Hong Xuan Do, Andrew Gronewold, Howard W. Reeves, Sandra M. Eberts, Richard G. Niswonger, R. Steve Regan, Randall J. Hunt
Integrated hydrologic model development and postprocessing for GSFLOW using pyGSFLOW
pyGSFLOW is a python package designed to create new GSFLOW integrated hydrologic models, read existing models, edit model input data, run GSFLOW models, process output, and visualize model data.
Authors
Joshua Larsen, Ayman H. Alzraiee, Richard G. Niswonger
Integrated hydrology and operations modeling to evaluate climate change impacts in an agricultural valley irrigated with snowmelt runoff
Applying models to developed agricultural regions remains a difficult problem because there are no existing modeling codes that represent both the complex physics of the hydrology and anthropogenic manipulations to water distribution and consumption. We apply an integrated groundwater – surface water and hydrologic river operations model to an irrigated river valley in northwestern...
Authors
Wesley Kitlasten, Eric D. Morway, Richard G. Niswonger, Murphy Gardner, Jeremy T. White, Enrique Triana, David J. Selkowitz
Baseflow age distributions and depth of active groundwater flow in a snow‐dominated mountain headwater basin
Deeper flows through bedrock in mountain watersheds could be important, but lack of data to characterize bedrock properties limits understanding. To address data scarcity, we combine a previously published integrated hydrologic model of a snow‐dominated, headwater basin of the Colorado River with a new method for dating baseflow age using dissolved gas tracers SF6, CFC‐113, N2, and Ar...
Authors
Rosemary W.H. Carroll, Andrew H. Manning, Richard G. Niswonger, David W Marchetti, Kenneth H. Williams
An agricultural water use package for MODFLOW and GSFLOW
The Agricultural Water Use (AG) Package was developed for simulating demand-driven and supply-constrained agricultural water use in MODFLOW and GSFLOW models. The AG Package uses pre-existing hydrologic simulation provided by MODFLOW and GSFLOW. Three options are available for simulating water use for agriculture: (1) user-specified demands, (2) demands determined by a user-specified...
Authors
Richard G. Niswonger
Version 2.3.0 of Coupled Ground-Water and Surface-Water Flow Model Based on the Integration of the Precipitation-Runoff Modeling System (PRMS) and the Modular Ground-Water Flow Model
GSFLOW is a coupled Groundwater and Surface-Water Flow model based on the integration of the U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS; Markstrom and others, 2015) and the U.S. Geological Survey Modular Groundwater Flow Model (MODFLOW-2005, Harbaugh, 2005; MODFLOW-NWT, Niswonger and others, 2011). In addition to the basic PRMS and MODFLOW simulation methods...
GSFLOW: Coupled Groundwater and Surface-Water Flow Model
Groundwater and Surface-water FLOW (GSFLOW) was developed to simulate coupled groundwater and surface-water resources. The model is based on the integration of the U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS) and the U.S. Geological Survey Modular Groundwater Flow Model (MODFLOW).
MODFLOW-NWT: A Newton Formulation for MODFLOW-2005
MODFLOW-NWT is a Newton-Raphson formulation for MODFLOW-2005 to improve solution of unconfined groundwater-flow problems. MODFLOW-NWT is a standalone program that is intended for solving problems involving drying and rewetting nonlinearities of the unconfined groundwater-flow equation.
GSFLOW: Coupled Groundwater and Surface-Water Flow Model, version 2.2.1
GSFLOW is a coupled Groundwater and Surface-Water Flow model based on the integration of the U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS; Markstrom and others, 2015) and the U.S. Geological Survey Modular Groundwater Flow Model (MODFLOW-2005, Harbaugh, 2005; MODFLOW-NWT, Niswonger and others, 2011). In addition to the basic PRMS and MODFLOW simulation methods...
GSFLOW: Coupled Groundwater and Surface-Water Flow Model, version 2.2.0
GSFLOW is a coupled Groundwater and Surface-Water Flow model based on the integration of the U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS; Markstrom and others, 2015) and the U.S. Geological Survey Modular Groundwater Flow Model (MODFLOW-2005, Harbaugh, 2005; MODFLOW-NWT, Niswonger and others, 2011). In addition to the basic PRMS and MODFLOW simulation methods...
pyGSFLOW v1.0.0
Python package software release for pyGSFLOW. pyGSFLOW is a python package to create, read, write, edit, and visualize GSFLOW models. Source code, examples, installation instructions, and documentation can be found at https://github.com/pygsflow/pygsflow
GSFLOW: Coupled Groundwater and Surface-Water Flow Model, version 2.1.0
GSFLOW is a coupled Groundwater and Surface-water FLOW model based on the integration of the USGS Precipitation-Runoff Modeling System (PRMS-V) and the USGS Modular Groundwater Flow Model (MODFLOW-2005 and MODFLOW-NWT). GSFLOW was developed to simulate coupled groundwater/surface-water flow in one or more watersheds by simultaneously simulating flow across the land surface, within...
CRT: Cascade Routing Tool to Define and Visualize Flow Paths for Grid-Based Watershed Models
The U.S. Geological Survey Cascade Routing Tool (CRT) is a computer application for watershed models that include the coupled Groundwater and Surface-water FLOW model GSFLOW and the Precipitation-Runoff Modeling System (PRMS). CRT generates output to define cascading surface and shallow subsurface flow paths for grid-based model domains.
Science and Products
Water for the Seasons
Water for the Seasons (WftS) is a four year study funded by the National Science Foundation and the U.S. Department of Agriculture. WtfS uses the Truckee-Carson River System (TCRS) as a pilot study to learn how to best link science with decision-making in snow-fed arid-land river systems. By working collaboratively with stakeholders, WftS aims to create a model for improving community climate...
Public supply water use reanalysis for the 2000-2020 period by HUC12, month, and year for the conterminous United States (ver. 2.0, August 2024)
The U.S. Geological Survey is developing national water-use models to support water resources management in the United States. Model benefits include a nationally consistent estimation approach, greater temporal and spatial resolution of estimates, efficient and automated updates of results, and capabilities to forecast water use into the future and assess model uncertainty. The term...
Thermoelectric-power condenser duty estimates by month and cooling type for use to calculate water use by power plant for the 2008-2020 reanalysis period for the conterminous United States
The U.S. Geological Survey (USGS) developed models to estimate the amount of water that is withdrawn and consumed by thermoelectric power plants (Diehl and others, 2013; Diehl and Harris, 2014; Harris and Diehl, 2019). The thermoelectric water use models are based on linked heat-and-water budgets that are constrained by power plant generation and cooling system technologies, the amount...
Thermoelectric-power water use reanalysis for the 2008-2020 period by power plant, month, and year for the conterminous United States
Previous work by the U.S. Geological Survey (USGS) developed models to estimate the amount of water that is withdrawn and consumed by thermoelectric power plants (Diehl and others, 2013; Diehl and Harris, 2014; Harris and Diehl, 2019 [full citations listed in srcinfo of the metadata file]). This data release presents a historical reanalysis of thermoelectric water use from 2008 to 2020...
Monthly crop irrigation withdrawals and efficiencies by HUC12 watershed for years 2000-2020 within the conterminous United States (ver. 2.0, September 2024)
The USGS has published United States water-use data every five years since 1950. To increase the temporal and spatial availability of water use estimates using nationally consistent methods, the USGS is developing national water-use models for each major water-use category. This data release publishes crop irrigation withdrawals for the conterminous United States (CONUS) that are...
Irrigation water use reanalysis for the 2000-20 period by HUC12, month, and year for the conterminous United States (ver. 2.0, September 2024)
This data release provides a monthly irrigation water use reanalysis for the period 2000-20 for all USGS Watershed Boundary Dataset of Subwatersheds (HUC12) in the conterminous United States (CONUS). Results include reference evapotranspiration (ETo), actual evapotranspiration (ETa), irrigated areas, consumptive use, and effective precipitation for each HUC12. ETo and ETa were estimated...
MODFLOW-NWT model used to simulate Potential Effects of Changes in Water Use in the Middle Carson River Basin for Eagle, Dayton, and Churchill Valleys, West-Central, Nevada
A three-dimensional MODFLOW-NWT groundwater flow model was developed to evaluate the impacts of alternative water management scenarios on the groundwater resources of Eagle, Dayton, and Churchill Valleys, Nevada. In addition, the resulting impact on flows in the Carson River and Lahontan Reservoir are also evaluated. During the economic boom that occurred from 2004-2006 in northwestern...
GSFLOW and MODSIM-GSFLOW model used to evaluate the potential effects of increased temperature on the Carson Valley watershed and agricultural system in eastern California and western Nevada
The USGS developed an integrated river operations-groundwater model using GSFLOW and MODSIM GSFLOW to simulate streamflow derived from snowmelt, the distribution of surface water based on the existing prior appropriations water doctrine, supplemental pumping in response to surface water shortfalls, and the resulting surface water-groundwater interactions in the Carson Valley in...
Nitrogen and phosphorus, other water quality parameters, and sediment temperature data for Incline Creek and Marlette Creek stream-lake interface, Lake Tahoe, Nevada, September 2013
This data set contains the following parameters: sediment and water temperature, dissolved nitrate plus nitrite dissolved, ammonium, total Kjeldahl nitrogen, soluble orthophosphate, dissolved phosphorus, total phosphorus, and dissolved organic carbon.
Water Use Diagram
Diagram of the process of water use from source (surface water, groundwater, reuse water) through transmission, utility reservoir, water treatment, distribution, and withdrawal for industry, residential, and commercial.
Diagram of the process of water use from source (surface water, groundwater, reuse water) through transmission, utility reservoir, water treatment, distribution, and withdrawal for industry, residential, and commercial.
Filter Total Items: 57
Automating physics-based models to estimate thermoelectric-power water use
Thermoelectric (TE) power plants withdraw more water than any other sector of water use in the United States and consume water at rates that can be significant especially in water-stressed regions. Historical TE water-use data have been inconsistent, incomplete, or discrepant, resulting in an increased research focus on improving the accuracy and availability of TE water-use data using...
Authors
Melissa A. Harris, Timothy H. Diehl, Lillian Gorman Sanisaca, Amy E. Galanter, Melissa Lombard, Kenneth Skinner, Catherine A. Chamberlin, Brendan A. McCarthy, Richard G. Niswonger, Jana Stewart, Kristen J. Valseth
Next generation public supply water withdrawal estimation for the conterminous United States using machine learning and operational frameworks
Estimation of human water withdrawals is more important now than ever due to uncertain water supplies, population growth, and climate change. Fourteen percent of the total water withdrawal in the United States is used for public supply, typically including deliveries to domestic, commercial, and occasionally including industrial, irrigation, and thermoelectric water withdrawal. Stewards...
Authors
Ayman H. Alzraiee, Richard G. Niswonger, Carol L. Luukkonen, Joshua Larsen, Donald Martin, Deidre Mary Herbert, Cheryl A. Buchwald, Cheryl A. Dieter, Lisa D. Miller, Jana Stewart, Natalie Houston, Scott R. Paulinski, Kristen Valseth
A probabilistic approach to training machine learning models using noisy data
Machine learning (ML) models are increasingly popular in environmental and hydrologic modeling, but they typically contain uncertainties resulting from noisy data (erroneous or outlier data). This paper presents a novel probabilistic approach that combines ML and Markov Chain Monte Carlo simulation to (1) detect and underweight likely noisy data, (2) develop an approach capable of...
Authors
Ayman H. Alzraiee, Richard G. Niswonger
Development and evaluation of public-supply community water service area boundaries for the conterminous United States
The water service area dataset, derived from the National Boundary Dataset for public-supply water systems in the United States, offers a detailed resolution surpassing county-level assessments, emphasizing water-centric land use. Crucial for linking populations and infrastructure to system withdrawals, it supports the creation of a national public-supply water-use model, enhancing...
Authors
Cheryl A. Buchwald, Natalie Houston, Jana Stewart, Ayman H. Alzraiee, Richard G. Niswonger, Joshua Larsen
Declining groundwater storage expected to amplify mountain streamflow reductions in a warmer world
Groundwater interactions with mountain streams are often simplified in model projections, potentially leading to inaccurate estimates of streamflow response to climate change. Here, using a high-resolution, integrated hydrological model extending 400 m into the subsurface, we find groundwater an important and stable source of historical streamflow in a mountainous watershed of the...
Authors
Rosemary W.H. Carroll, Richard G. Niswonger, Craig Ulrich, Charuleka Varadharajan, Erica Siirila-Woodburn, Kenneth H. Williams
An agricultural package for MODFLOW 6 using the Application Programming Interface
An agricultural water use package has been developed for MODFLOW 6 using the MODFLOW Application Programming Interface (API). The MODFLOW API Agricultural Water Use Package (API-Ag) was based on the approach to simulate irrigation demand in the MODFLOW-NWT and GSFLOW Agricultural Water Use (AG) Package. The API-Ag Package differs from the previous approach by implementing new features...
Authors
Joshua Larsen, Christian D. Langevin, Joseph D. Hughes, Richard G. Niswonger
Assessing potential effects of changes in water use in the middle Carson River Basin with a numerical groundwater-flow model, Eagle, Dayton, and Churchill Valleys, west-central Nevada
During the economic boom of the mid part of the first decade of the 2000s in northwestern Nevada, municipal and housing growth increased use of the water resources of this semi-arid region. In 2008, when the economy slowed, new housing development stopped, and immediate pressure on groundwater resources abated. The U.S. Geological Survey, in cooperation with the Bureau of Reclamation...
Authors
Eric D. Morway, Susan G. Buto, Richard G. Niswonger, Justin L. Huntington
Can hydrological models benefit from using global soil moisture, evapotranspiration, and runoff products as calibration targets?
Hydrological models are usually calibrated to in-situ streamflow observations with reasonably long and uninterrupted records. This is challenging for poorly gage or ungaged basins where such information is not available. Even for gaged basins, the single-objective calibration to gaged streamflow cannot guarantee reliable forecasts because, as has been documented elsewhere, the inverse...
Authors
Yiwen Mei, Juliane Mai, Hong Xuan Do, Andrew Gronewold, Howard W. Reeves, Sandra M. Eberts, Richard G. Niswonger, R. Steve Regan, Randall J. Hunt
Integrated hydrologic model development and postprocessing for GSFLOW using pyGSFLOW
pyGSFLOW is a python package designed to create new GSFLOW integrated hydrologic models, read existing models, edit model input data, run GSFLOW models, process output, and visualize model data.
Authors
Joshua Larsen, Ayman H. Alzraiee, Richard G. Niswonger
Integrated hydrology and operations modeling to evaluate climate change impacts in an agricultural valley irrigated with snowmelt runoff
Applying models to developed agricultural regions remains a difficult problem because there are no existing modeling codes that represent both the complex physics of the hydrology and anthropogenic manipulations to water distribution and consumption. We apply an integrated groundwater – surface water and hydrologic river operations model to an irrigated river valley in northwestern...
Authors
Wesley Kitlasten, Eric D. Morway, Richard G. Niswonger, Murphy Gardner, Jeremy T. White, Enrique Triana, David J. Selkowitz
Baseflow age distributions and depth of active groundwater flow in a snow‐dominated mountain headwater basin
Deeper flows through bedrock in mountain watersheds could be important, but lack of data to characterize bedrock properties limits understanding. To address data scarcity, we combine a previously published integrated hydrologic model of a snow‐dominated, headwater basin of the Colorado River with a new method for dating baseflow age using dissolved gas tracers SF6, CFC‐113, N2, and Ar...
Authors
Rosemary W.H. Carroll, Andrew H. Manning, Richard G. Niswonger, David W Marchetti, Kenneth H. Williams
An agricultural water use package for MODFLOW and GSFLOW
The Agricultural Water Use (AG) Package was developed for simulating demand-driven and supply-constrained agricultural water use in MODFLOW and GSFLOW models. The AG Package uses pre-existing hydrologic simulation provided by MODFLOW and GSFLOW. Three options are available for simulating water use for agriculture: (1) user-specified demands, (2) demands determined by a user-specified...
Authors
Richard G. Niswonger
Version 2.3.0 of Coupled Ground-Water and Surface-Water Flow Model Based on the Integration of the Precipitation-Runoff Modeling System (PRMS) and the Modular Ground-Water Flow Model
GSFLOW is a coupled Groundwater and Surface-Water Flow model based on the integration of the U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS; Markstrom and others, 2015) and the U.S. Geological Survey Modular Groundwater Flow Model (MODFLOW-2005, Harbaugh, 2005; MODFLOW-NWT, Niswonger and others, 2011). In addition to the basic PRMS and MODFLOW simulation methods...
GSFLOW: Coupled Groundwater and Surface-Water Flow Model
Groundwater and Surface-water FLOW (GSFLOW) was developed to simulate coupled groundwater and surface-water resources. The model is based on the integration of the U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS) and the U.S. Geological Survey Modular Groundwater Flow Model (MODFLOW).
MODFLOW-NWT: A Newton Formulation for MODFLOW-2005
MODFLOW-NWT is a Newton-Raphson formulation for MODFLOW-2005 to improve solution of unconfined groundwater-flow problems. MODFLOW-NWT is a standalone program that is intended for solving problems involving drying and rewetting nonlinearities of the unconfined groundwater-flow equation.
GSFLOW: Coupled Groundwater and Surface-Water Flow Model, version 2.2.1
GSFLOW is a coupled Groundwater and Surface-Water Flow model based on the integration of the U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS; Markstrom and others, 2015) and the U.S. Geological Survey Modular Groundwater Flow Model (MODFLOW-2005, Harbaugh, 2005; MODFLOW-NWT, Niswonger and others, 2011). In addition to the basic PRMS and MODFLOW simulation methods...
GSFLOW: Coupled Groundwater and Surface-Water Flow Model, version 2.2.0
GSFLOW is a coupled Groundwater and Surface-Water Flow model based on the integration of the U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS; Markstrom and others, 2015) and the U.S. Geological Survey Modular Groundwater Flow Model (MODFLOW-2005, Harbaugh, 2005; MODFLOW-NWT, Niswonger and others, 2011). In addition to the basic PRMS and MODFLOW simulation methods...
pyGSFLOW v1.0.0
Python package software release for pyGSFLOW. pyGSFLOW is a python package to create, read, write, edit, and visualize GSFLOW models. Source code, examples, installation instructions, and documentation can be found at https://github.com/pygsflow/pygsflow
GSFLOW: Coupled Groundwater and Surface-Water Flow Model, version 2.1.0
GSFLOW is a coupled Groundwater and Surface-water FLOW model based on the integration of the USGS Precipitation-Runoff Modeling System (PRMS-V) and the USGS Modular Groundwater Flow Model (MODFLOW-2005 and MODFLOW-NWT). GSFLOW was developed to simulate coupled groundwater/surface-water flow in one or more watersheds by simultaneously simulating flow across the land surface, within...
CRT: Cascade Routing Tool to Define and Visualize Flow Paths for Grid-Based Watershed Models
The U.S. Geological Survey Cascade Routing Tool (CRT) is a computer application for watershed models that include the coupled Groundwater and Surface-water FLOW model GSFLOW and the Precipitation-Runoff Modeling System (PRMS). CRT generates output to define cascading surface and shallow subsurface flow paths for grid-based model domains.