The U.S. Geological Survey constructed a steady-state numerical groundwater flow model in cooperation with Des Moines Water Works (DMWW) to simulate groundwater flow conditions in the Des Moines River alluvial aquifer (DMRA) during winter low-flow conditions typical of December 2018-2020. The Des Moines River alluvial aquifer (DMRA) is an important source of water for Des Moines Water Works (DMWW), the municipal water utility that serves residential and commercial water needs in the city of Des Moines, Iowa and surrounding municipalities. A comprehensive understanding of groundwater flow processes in the DMRA is needed for DMWW to make decisions related to the management of this water resource. A three-layered model was constructed using MODFLOW-NWT to simulate an area of about 15 square kilometers near Prospect Park in Des Moines, Iowa. The model has 130 rows and 130 columns of cells within the model boundary. Parameter ESTimation software (PEST) was used for model calibration to assess and optimize performance of individual parameters including the horizontal and vertical hydraulic conductivity of the various units, evapotranspiration rate, and recharge rate. This USGS data release contains all the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/ofr20211110).

The U.S. Geological Survey constructed a steady-state numerical groundwater flow model in cooperation with Des Moines Water Works (DMWW) to simulate groundwater flow conditions in the Des Moines River alluvial aquifer (DMRA) during winter low-flow conditions typical of December 2018-2020. The Des Moines River alluvial aquifer (DMRA) is an important source of water for Des Moines Water Works (DMWW), the municipal water utility that serves residential and commercial water needs in the city of Des Moines, Iowa and surrounding municipalities. A comprehensive understanding of groundwater flow processes in the DMRA is needed for DMWW to make decisions related to the management of this water resource. A three-layered model was constructed using MODFLOW-NWT to simulate an area of about 15 square kilometers near Prospect Park in Des Moines, Iowa. The model has 130 rows and 130 columns of cells within the model boundary. Parameter ESTimation software (PEST) was used for model calibration to assess and optimize performance of individual parameters including the horizontal and vertical hydraulic conductivity of the various units, evapotranspiration rate, and recharge rate. This USGS data release contains all the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/ofr20211110).

A three-dimensional MODFLOW-NWT model was constructed to better understand the effects of drought stress on the Cedar River alluvial aquifer, the principal source of municipal water for the City of Cedar Rapids, Iowa. Historically, the aquifer supported the production needs of the City of Cedar Rapids and surrounding area but between July 2011 and February 2013, Iowa experienced severe drought conditions that affected water availability for communities that relied on alluvial aquifers for their production needs. During that time, the City of Cedar Rapids observed water level declines in their horizontal collector wells (HCW) of as much as about 11 meters. Pumping from affected production wells had to be halted to prevent damage to the pumps and wells and caused concern about the reliability of the alluvial aquifer under future drought conditions. In 2013, the U.S. Geological Survey (USGS), in cooperation with the City of Cedar Rapids, began a study to better understand the effects of drought stress on the Cedar River alluvial aquifer using a numerical groundwater flow model which combined published hydrogeologic data with airborne, waterborne, down-hole, and land-based geophysical survey data collected from 2015 to 2017. The model (1) provided a detailed three-dimensional lithologic model of the Cedar River alluvial aquifer and surrounding area, (2) improved the conceptual model for the groundwater flow system, and (3) evaluated hydrogeologic characteristics of aquifer materials. Two models were constructed for this study. A steady-state model of mean hydrologic conditions for November 2015 and a transient model to simulate conditions from October 1, 2016, to August 31, 2018 (calibration period), and from October 1, 2011, to April 30, 2013 (simulation period). Additional scenarios using the transient model simulate drought conditions from October 2011 to April 2013 and evaluate the transient drought conditions with modifications to the riverbed. The numerical models were developed as a tool for use by water managers to better understand the potential effects of drought and increased demand on production wells. This USGS data release contains all the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20215065).

A three-dimensional MODFLOW-NWT model was constructed to better understand the effects of drought stress on the Cedar River alluvial aquifer, the principal source of municipal water for the City of Cedar Rapids, Iowa. Historically, the aquifer supported the production needs of the City of Cedar Rapids and surrounding area but between July 2011 and February 2013, Iowa experienced severe drought conditions that affected water availability for communities that relied on alluvial aquifers for their production needs. During that time, the City of Cedar Rapids observed water level declines in their horizontal collector wells (HCW) of as much as about 11 meters. Pumping from affected production wells had to be halted to prevent damage to the pumps and wells and caused concern about the reliability of the alluvial aquifer under future drought conditions. In 2013, the U.S. Geological Survey (USGS), in cooperation with the City of Cedar Rapids, began a study to better understand the effects of drought stress on the Cedar River alluvial aquifer using a numerical groundwater flow model which combined published hydrogeologic data with airborne, waterborne, down-hole, and land-based geophysical survey data collected from 2015 to 2017. The model (1) provided a detailed three-dimensional lithologic model of the Cedar River alluvial aquifer and surrounding area, (2) improved the conceptual model for the groundwater flow system, and (3) evaluated hydrogeologic characteristics of aquifer materials. Two models were constructed for this study. A steady-state model of mean hydrologic conditions for November 2015 and a transient model to simulate conditions from October 1, 2016, to August 31, 2018 (calibration period), and from October 1, 2011, to April 30, 2013 (simulation period). Additional scenarios using the transient model simulate drought conditions from October 2011 to April 2013 and evaluate the transient drought conditions with modifications to the riverbed. The numerical models were developed as a tool for use by water managers to better understand the potential effects of drought and increased demand on production wells. This USGS data release contains all the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20215065).

A previously calibrated MODFLOW-NWT groundwater-flow model (https://doi.org/10.3133/sir20205118) was used to determine the effects of climate variability under a range of future climatic conditions on groundwater resources in the reach 1 of the Washita River alluvial aquifer in western Oklahoma. The study area focuses on reach 1 of the Washita River alluvial aquifer; the entire Washita River alluvial aquifer consists of four administrative sections, or reaches, that are designated as reaches 1–4 by the Oklahoma Water Resources Board (OWRB, 2012). To approximate a range in future base-flow conditions in reach 1 of the Washita River alluvial aquifer and base-flow into Foss Reservoir, the Coupled Model Intercomparison Project Phase 5 Global Climate Model climate data were downscaled to watershed scale using monthly Bias-Correction Spatial Disaggregation techniques. A time series of scaling factors was developed and spatially interpolated for three climate scenarios (central tendency, warmer/drier, and less warm-wetter) representing a range of future climate conditions for the period 2050–2079. These scaling factors were then applied to an existing soil-water-balance model (https://doi.org/10.3133/sir20205118) with climate data for the baseline period 1985–2014 to produce recharge and evapotranspiration estimations for this future period. The downscaled climate data were applied to the groundwater-flow model of the reach 1 of the Washita River alluvial aquifer using MODFLOW-NWT. This data release contains the input and output files for the scenarios described in the associated model documentation report (https://doi.org/10.3133/sir20245082).

A previously calibrated MODFLOW-NWT groundwater-flow model (https://doi.org/10.3133/sir20205118) was used to determine the effects of climate variability under a range of future climatic conditions on groundwater resources in the reach 1 of the Washita River alluvial aquifer in western Oklahoma. The study area focuses on reach 1 of the Washita River alluvial aquifer; the entire Washita River alluvial aquifer consists of four administrative sections, or reaches, that are designated as reaches 1–4 by the Oklahoma Water Resources Board (OWRB, 2012). To approximate a range in future base-flow conditions in reach 1 of the Washita River alluvial aquifer and base-flow into Foss Reservoir, the Coupled Model Intercomparison Project Phase 5 Global Climate Model climate data were downscaled to watershed scale using monthly Bias-Correction Spatial Disaggregation techniques. A time series of scaling factors was developed and spatially interpolated for three climate scenarios (central tendency, warmer/drier, and less warm-wetter) representing a range of future climate conditions for the period 2050–2079. These scaling factors were then applied to an existing soil-water-balance model (https://doi.org/10.3133/sir20205118) with climate data for the baseline period 1985–2014 to produce recharge and evapotranspiration estimations for this future period. The downscaled climate data were applied to the groundwater-flow model of the reach 1 of the Washita River alluvial aquifer using MODFLOW-NWT. This data release contains the input and output files for the scenarios described in the associated model documentation report (https://doi.org/10.3133/sir20245082).

A three-dimensional groundwater flow model, MODFLOW 6, was developed to provide a better understanding of the hydrogeology of the Harney Basin, southeastern Oregon. The model was used to investigate the historical groundwater-level decline and storage loss associated with anthropogenic groundwater demands. The model was calibrated to 1930 through 2018 conditions. This USGS data release contains all of the input and output files for the simulation described in the associated model documentation report (https://doi.org/10.3133/sir2023XXXX)

A three-dimensional groundwater flow model, MODFLOW 6, was developed to provide a better understanding of the hydrogeology of the Harney Basin, southeastern Oregon. The model was used to investigate the historical groundwater-level decline and storage loss associated with anthropogenic groundwater demands. The model was calibrated to 1930 through 2018 conditions. This USGS data release contains all of the input and output files for the simulation described in the associated model documentation report (https://doi.org/10.3133/sir2023XXXX)

A three-dimensional groundwater flow model, MODFLOW 6, was developed to provide a better understanding of the hydrogeology of the Harney Basin, southeastern Oregon. The model was used to investigate the historical groundwater-level decline and storage loss associated with anthropogenic groundwater demands. The model was calibrated to 1930 through 2018 conditions. This USGS data release contains all of the input and output files for the simulation described in the associated model documentation report (https://doi.org/10.3133/sir2023XXXX)

This groundwater model archive documents a transient, regional-scale numerical model of the Long Island aquifer system that simulates hydrologic conditions for the period 1900-2019 using US Geological Survey’s groundwater modeling software MODFLOW 6 (Hughes and others, 2017). The development and calibration of the numerical model is documented in Walter and others, 2024. The model input and output files included in this data release are documented in the readme.txt. The model simulates historical water levels, stream flows, and the position of the saltwater interface in response to time-varying changes in pumping and recharge stresses for the period 1900-2019. This archive also contains input and output files for scenarios developed to simulate hydrologic conditions at annual and seasonal time scales averaged for the period 2010-2019, a five-year drought, and sea level rise of 6 feet.