The U.S. Geological Survey, in cooperation with Broward County Environmental Planning and Resilience Division, has developed a groundwater/surface-water model to evaluate the response of the drainage infrastructure and groundwater system in Broward County to increases in sea level and potential changes in precipitation. The model was constructed using a modified version of MODFLOW-NWT, with the surface-water system represented using the Surface-Water Routing process and the Urban Runoff Process. The surface-water drainage system within this newly developed model actively simulates the extensive canal network using level-pool routing and active structures representing gates, weirs, culverts, and pumps. Steady-state and transient simulation results represented historical conditions (2013-17). Simulation results incorporating increased sea level and precipitation were used to evaluate the effects on the surface-water drainage system and wet season groundwater levels. Four future sea-level scenarios were simulated by modifying the historical inputs for both the steady-state and the transient models to represent mean sea levels of 0.5, 2.0, 2.5, and 3.0 ft above the North American Vertical Datum of 1988. This USGS data release contains all of the input and output files for the simulations described in the associated model documentation report. (https://doi.org/10.3133/sir20225074)

A three-dimensional, surface-water/groundwater model (MODFLOW-NWT with the Surface-Water Routing Process) was developed to the predict the effects of groundwater pumpage on canal leakage and regional groundwater flow in urban portions of Miami-Dade County, Florida. The model was calibrated by using observation data collected from 1997 through 2004. The model calibration was verified using observation data collected from 2005 through 2010. The model is designed to simulate surface-water stage and discharge in the managed canal system and dynamic canal leakage to the Biscayne aquifer as well as seepage to the canal from the aquifer. The model was used to evaluate the effect of increased groundwater pumpage and (or) increased sea level on canal leakage, regional groundwater flow, and the position of the freshwater-seawater interface. This USGS data release contains all of the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20145162). This data release also includes (1) postprocessing python scripts, (2) python source code used by pre-processing scripts, (3) MODFLOW-NWT (v 1.0.8) source code with the General Finite Difference (GFD) boundary package, and (4) ZONEBUDGET (v 3.01) source code.

A three-dimensional, surface-water/groundwater model (MODFLOW-NWT with the Surface-Water Routing Process) was developed to the predict the effects of groundwater pumpage on canal leakage and regional groundwater flow in urban portions of Miami-Dade County, Florida. The model was calibrated by using observation data collected from 1997 through 2004. The model calibration was verified using observation data collected from 2005 through 2010. The model is designed to simulate surface-water stage and discharge in the managed canal system and dynamic canal leakage to the Biscayne aquifer as well as seepage to the canal from the aquifer. The model was used to evaluate the effect of increased groundwater pumpage and (or) increased sea level on canal leakage, regional groundwater flow, and the position of the freshwater-seawater interface. This USGS data release contains all of the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20145162). This data release also includes (1) postprocessing python scripts, (2) python source code used by pre-processing scripts, (3) MODFLOW-NWT (v 1.0.8) source code with the General Finite Difference (GFD) boundary package, and (4) ZONEBUDGET (v 3.01) source code.

This groundwater-flow model archive contains all of the input and output files for an inset MODFLOW-NWT model extracted from the northern (Wisconsin) half of a published USGS steady-state regional model of the Upper Fox River Basin in the U.S. Upper Midwest. The construction and details of the published USGS steady-state model of the Upper Fox River Basin is outlined in the U.S. Geological Survey Scientific Investigations Report 2018-5038 (https://doi.org/10.3133/sir20185038). The regional model is archived in the data release at https://doi.org/10.5066/F76D5R5V. The extracted model was used to demonstrate an innovative new method for delinating fen distribution and discharge using the MODFLOW UZF package. The extracted model incorporates the Mukwonago River Basin, a 10-digit hydrologic unit code (HUC10) basin occupying 86.2 mi2 (223 km2) in southeastern Wisconsin. The extracted model was used to demonstrate how regional and local flow patterns can be enhanced by adding a version of the UZF file that automatically inserts “seepage drains” in cells where the water table is near the land surface (within the “undulation depth”). Details on the extracted model construction and calibration, including preparation of the “stripped-down” UZF file central to the proposed fen delineation method can be found in the supporting information of the journal article in Groundwater (https://doi.org/10.1111/gwat.12931). This USGS data release contains all of the input and output files for the simulations described in the journal article in Groundwater (https://doi.org/10.1111/gwat.12931).

This groundwater-flow model archive contains all of the input and output files for an inset MODFLOW-NWT model extracted from the northern (Wisconsin) half of a published USGS steady-state regional model of the Upper Fox River Basin in the U.S. Upper Midwest. The construction and details of the published USGS steady-state model of the Upper Fox River Basin is outlined in the U.S. Geological Survey Scientific Investigations Report 2018-5038 (https://doi.org/10.3133/sir20185038). The regional model is archived in the data release at https://doi.org/10.5066/F76D5R5V. The extracted model was used to demonstrate an innovative new method for delinating fen distribution and discharge using the MODFLOW UZF package. The extracted model incorporates the Mukwonago River Basin, a 10-digit hydrologic unit code (HUC10) basin occupying 86.2 mi2 (223 km2) in southeastern Wisconsin. The extracted model was used to demonstrate how regional and local flow patterns can be enhanced by adding a version of the UZF file that automatically inserts “seepage drains” in cells where the water table is near the land surface (within the “undulation depth”). Details on the extracted model construction and calibration, including preparation of the “stripped-down” UZF file central to the proposed fen delineation method can be found in the supporting information of the journal article in Groundwater (https://doi.org/10.1111/gwat.12931). This USGS data release contains all of the input and output files for the simulations described in the journal article in Groundwater (https://doi.org/10.1111/gwat.12931).

A previously developed groundwater flow model (https://doi.org/10.5066/P9051RUT) was slightly modified to estimate the risk-based discrete relation between groundwater extraction and surface-water/groundwater exchange. Previously, the concept of a ''capture map'' has been put forward as a means to effectively summarize this relation for decision-making consumption. While capture maps have enjoyed success in the environmental simulation industry, they are deterministic, ignoring uncertainty in the underlying model. Furthermore, capture maps are not typically calculated in a manner that facilitates analysis of varying combinations of extraction locations and/or reaches. That is, they are typically constructed with focus on a single reach or group of reaches. The former of these limitations is important for conveying risk to decision makers, while the latter is important for decision-making support related to surface-water management, where future foci may include reaches that were not the focus of the original capture analysis. Herein, we use a MODFLOW-NWT groundwater/surface-water model of the lower San Antonio River, Texas, USA to demonstrate a technique to estimate risk-based and spatially discrete streamflow depletion potential. This USGS data release contains all of the input and output files for the simulations described in the associated journal article (https://doi.org/10.1111/gwat.13080)

The U.S. Geological Survey (USGS), in cooperation with the U.S Fish and Wildlife Service, has investigated the hydrology of the Great Dismal Swamp (Swamp) National Wildlife Refuge (Refuge) in Virginia and North Carolina and developed a three-dimensional numerical model to simulate groundwater and surface-water hydrology. The model was developed with MODFLOW-NWT, a USGS numerical groundwater flow modeling program, in combination with the Surface-Water Routing Process, a software package that simulates dynamic surface-water flows, water-control-structure management, and groundwater/surface-water interactions. The steady-state model was calibrated to average spring conditions using automated parameter estimation software (PEST) to reduce simulation errors and assess model parameter sensitivity. The model was then used to simulate wet and dry climatic conditions and a variety of hypothetical scenarios in which water levels in the Swamp were raised and lowered by simulated management of water control structures. Results of the model simulations indicate that, under average spring conditions, precipitation is the primary water input (92%); surface-water (5%) and groundwater (3%) inflows make up the remainder. The primary outflow (or loss) is evapotranspiration (55%), with surface outflows (about 41%) and groundwater outflow (about 4%) making up the remainder. Simulated adjustment of water-control structure weir levels demonstrates that groundwater levels are affected by water levels in adjacent ditches and that surface-water and groundwater levels can be controlled through management of water control structures, allowing the Refuge to better manage fire risks and preserve forested-wetland ecosystems in the Refuge. The 13 water control structures proposed in the simulated scenario representing possible future conditions effectively raised simulated water levels in the northeastern corner of the study area, a goal of the Refuge management. Results of this study demonstrate use of MODFLOW with the Surface-Water Routing Process for simulating water management options in peat wetlands and will help Refuge managers to better understand existing hydrologic conditions, assess the hydrologic effects of planned changes to water control structures, and apply the new simulation tool to guide water management on the Refuge.

The U.S. Geological Survey (USGS), in cooperation with the U.S Fish and Wildlife Service, has investigated the hydrology of the Great Dismal Swamp (Swamp) National Wildlife Refuge (Refuge) in Virginia and North Carolina and developed a three-dimensional numerical model to simulate groundwater and surface-water hydrology. The model was developed with MODFLOW-NWT, a USGS numerical groundwater flow modeling program, in combination with the Surface-Water Routing Process, a software package that simulates dynamic surface-water flows, water-control-structure management, and groundwater/surface-water interactions. The steady-state model was calibrated to average spring conditions using automated parameter estimation software (PEST) to reduce simulation errors and assess model parameter sensitivity. The model was then used to simulate wet and dry climatic conditions and a variety of hypothetical scenarios in which water levels in the Swamp were raised and lowered by simulated management of water control structures. Results of the model simulations indicate that, under average spring conditions, precipitation is the primary water input (92%); surface-water (5%) and groundwater (3%) inflows make up the remainder. The primary outflow (or loss) is evapotranspiration (55%), with surface outflows (about 41%) and groundwater outflow (about 4%) making up the remainder. Simulated adjustment of water-control structure weir levels demonstrates that groundwater levels are affected by water levels in adjacent ditches and that surface-water and groundwater levels can be controlled through management of water control structures, allowing the Refuge to better manage fire risks and preserve forested-wetland ecosystems in the Refuge. The 13 water control structures proposed in the simulated scenario representing possible future conditions effectively raised simulated water levels in the northeastern corner of the study area, a goal of the Refuge management. Results of this study demonstrate use of MODFLOW with the Surface-Water Routing Process for simulating water management options in peat wetlands and will help Refuge managers to better understand existing hydrologic conditions, assess the hydrologic effects of planned changes to water control structures, and apply the new simulation tool to guide water management on the Refuge.

A previously published groundwater flow model (https://pubs.usgs.gov/sir/2005/5089/) was revised with refined grid spacing and updated hydrogeolgic framework and hydrologic properties (http://doi.org/10.3133/sir20155061) and used in this study to predict the effects of Upper Floridan aquifer (UFA) groundwater pumpage on horizontal hydraulic-head gradients in the upper-water-bearing zone of the UFA in the downtown Brunswick area, Glynn County, Georgia. The model used MOFLOW-2000 and was calibrated using groundwater-use information for October 2015, which was the basis for the 2015 Base Case simulation. A comparison of the 2015 Base Case simulation with seven groundwater-management scenarios evaluated potential changes to the upper-water-bearing zone of the UFA near downtown Brunswick. Particle-tracking analysis, using MODPATH, provided pathlines and time-of-travel for the 2015 Base Case simulation and scenario C. This USGS data release contains all of the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20195035).

A previously published groundwater flow model (https://pubs.usgs.gov/sir/2005/5089/) was revised with refined grid spacing and updated hydrogeolgic framework and hydrologic properties (http://doi.org/10.3133/sir20155061) and used in this study to predict the effects of Upper Floridan aquifer (UFA) groundwater pumpage on horizontal hydraulic-head gradients in the upper-water-bearing zone of the UFA in the downtown Brunswick area, Glynn County, Georgia. The model used MOFLOW-2000 and was calibrated using groundwater-use information for October 2015, which was the basis for the 2015 Base Case simulation. A comparison of the 2015 Base Case simulation with seven groundwater-management scenarios evaluated potential changes to the upper-water-bearing zone of the UFA near downtown Brunswick. Particle-tracking analysis, using MODPATH, provided pathlines and time-of-travel for the 2015 Base Case simulation and scenario C. This USGS data release contains all of the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20195035).