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Interannual differences in the water quality of Anvil Lake, WI, were examined to determine how water level and climate affect the hydrodynamics and trophic state of shallow lakes, and their importance compared to anthropogenic changes in the watershed. To determine how changes in water level may affect these processes, the General Lake Model (GLM) was used to simulate how the lake’s thermal structure should change in response to changes in water level using R. This dataset includes the data inputs to the GLM model and the direct outputs from the model. Model Calibration (GLM_CalibrationZ); Simulation of with Deep Lake and Cold Weather (GLM_Deep_Cold_SimulationZ); Simulation of with Deep Lake and Hot Weather (GLM_Deep_Hot_SimulationZ);...
A three-dimensional, groundwater-flow model developed by Halford and Jackson (https://doi.org/10.3133/pp1863) was used to simulate effects of future (2020—2120) groundwater pumping on water levels and natural discharges in the Alkali Flat–Furnace Creek Ranch (AFFCR), Ash Meadows, Pahute Mesa–Oasis Valley (PMOV), and Pahrump to Death Valley South (PDVS) groundwater basins, southern Nevada and California. Four pumping scenarios were simulated, including a base case and scenarios A, B, and C. Scenarios were simulated from 1913 to 2120, with historical pumping occurring from 1913 to 2010, historical 2010 pumping rates projected from 2010 to 2020, and scenario pumping beginning in 2020. The base case projected 2010 pumping...
The integrated hydrologic-flow model, called the Osage Nation Integrated Hydrologic Model (ONIHM) was developed to assess water availability in the Osage Nation. This model was developed using the MODFLOW-One Water Hydrologic Model (MF-OWHM) code. The ONIHM was discretized into an orthogonal grid of 276 rows and 289 columns, and each grid cell measured 1,312.34 feet (ft) per side, with eight variably thick vertical layers that represented the alluvial and bedrock aquifers within the study area, including the Vamoosa-Ada aquifer and other minor bedrock aquifers deposited during the Pennsylvanian Period. The ONIHM was delineated into 128 water-balance subregions based on surface watersheds, land cover, and water supply...
An integrated hydrologic-flow model, called the Central Platte Integrated Hydrologic Model, was constructed using the MODFLOW-One-Water Hydrologic Model code with the Newton solver. This code integrates climate, landscape, surface water, and groundwater-flow processes in a fully coupled approach. This study provided the Central Platte Natural Resources District (CPNRD) with an advanced numerical modeling tool to assist with the update of their Groundwater Management Plan by providing them information on modeled future GW levels under different climate scenarios and management practices. This tool will allow the CPNRD to evaluate other scenarios as management changes in the future. A predevelopment model simulated...
The U.S. Geological Survey, in cooperation with the Oklahoma Water Resources Board, constructed a finite-difference numerical groundwater-flow model of the Salt Fork Red River aquifer using MODFLOW with the Newton formulation solver (MODFLOW-NWT). The 1973 Oklahoma Water Law requires the Oklahoma Water Resources Board to conduct hydrologic investigations of the State’s aquifers to support a determination of the maximum annual yield (MAY) for each groundwater basin. The MAY is defined as the amount of fresh groundwater that can be withdrawn annually while ensuring a minimum 20-year life of the groundwater basin. For alluvium and terrace aquifers, the groundwater-basin-life requirement is satisfied if, after 20 years...
A three-dimensional groundwater flow model was developed to simulate the effects of withdrawals on the groundwater-flow systems of five aquifers in and around Ocean County, New Jersey—the unconfined Kirkwood-Cohansey aquifer system and Vincentown aquifer, and three confined aquifers--the Rio Grande water-bearing zone, the Atlantic City 800-foot sand, and the Piney Point aquifer. A transient model was used to simulate conditions that represent no groundwater withdrawals, 2000–2003 groundwater withdrawals, and maximum-allocation groundwater withdrawals. Particle-tracking analysis, using results from two steady-state simulations, determine flow paths and travel times to near-shore wells screened in the unconfined Kirkwood-Cohansey...
A three-dimensional groundwater flow model (MODFLOW2000) of the Atlantic Coastal Plain aquifers and confining units was developed to evaluate groundwater availability and to forecast the potential effects of climate change on groundwater levels in the study area. Two existing groundwater flow models that simulated flow and water use in the Coastal Plain aquifers of North Carolina (NC), South Carolina (SC), and parts of Georgia and Virginia, were combined and updated to provide a single model. Revisions to the model incorporated additional hydrogeologic, geologic, water-level, and water-use data and hydrogeologic inconsistencies at the NC-SC border reconciled since the development of the previous models. The new...
The U.S. Geological Survey, in cooperation with the Oklahoma Water Resources Board, constructed a finite-difference numerical groundwater-flow model of the Washita River alluvial aquifer using MODFLOW-2005 with the Newton formulation solver (MODFLOW-NWT). The 1973 Oklahoma Water Law (82 OK Stat § 82-1020.5) requires the Oklahoma Water Resources Board to conduct hydrologic investigations of the State's aquifers to support a determination of the maximum annual yield (MAY) for each groundwater basin. A permanent MAY and EPS have not been established for the Washita River alluvial aquifer; thus, the U.S. Geological Survey, in cooperation with the Oklahoma Water Resources Board, conducted calibration and simulations...
Summary Carroll et al. (2009) state that the United States Geological Survey (USGS) Death Valley Regional Flow System (DVRFS) model, which is based on MODFLOW, is “conceptually inaccurate in that it models an unconfined aquifer as a confined system and does not simulate unconfined drawdown in transient pumping simulations.” Carroll et al. (2009) claim that “more realistic estimates of water availability” can be produced by a SURFACT-based model of the DVRFS that simulates unconfined groundwater flow and limits withdrawals from wells to avoid excessive drawdown. Differences in results from the original MODFLOW-based model and the SURFACT-based model stem primarily from application by Carroll et al. (2009) of head...
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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...
A three-dimensional, groundwater model (MODFLOW-2005) was developed to determine effects of future (2019–2100) groundwater development on water levels and natural discharges in the Alkali Flat–Furnace Creek Ranch (AFFCR), Ash Meadows, Pahute Mesa–Oasis Valley (PMOV), and Pahrump to Death Valley South (PDVS) groundwater basins, southern Nevada and California. Two pumping scenarios were developed. Scenario 1 assumed pumping continues at the current (2018) rate through 2100. Scenario 2 assumed all pumping stops in 2018 so that recovery can be observed from 2019–2100. Input and output files for the predictive simulations are in the model and output directories, respectively. The predictive model was calibrated with...
Hypothetical two-dimensional, steady-state groundwater flow models of a previously published 1988 model calibration exercise were developed using the finite-difference computer code, MODFLOW-2005, to demonstrate the power of modern parameter estimation and uncertainty approaches. For this study, an initial run recreated the 1988 "truth" model. The true model was then simplified to account for information not provided the participants in the 1988 calibration exercise. Increasing sophistication was brought to bear to demonstrate how problems identified in 1988 were overcome using modern software approaches. This USGS data release contains all of the input and output to run the model simulations described in the associated...
The Mississippi Alluvial Plain (MAP) is one of the most important agricultural regions in the United States and underlies about 32,000 square miles of Missouri, Kentucky, Tennessee, Mississippi, Louisiana, and Arkansas. The MAP region supports a multibillion-dollar agricultural industry. The MAP is part of the Mississippi Embayment with several water-bearing units that make up the Mississippi Embayment Regional Aquifer System (MERAS). These water bearing units include the Mississippi River Valley Alluvial aquifer, Claiborne aquifers and Wilcox aquifers. In northeastern Arkansas, the Cache area has been designated as a critical groundwater areas because of decades of groundwater declines that resulted from past and...
A three-dimensional groundwater flow model using MODFLOW 6 (version 6.2.2) was developed and calibrated for unconsolidated Coastal Plain aquifers underlying the Joint Base McGuire-Dix-Lakehurst (JBMDL) and vicinity, New Jersey, to evaluate groundwater flow pathways of per- and polyfluoroalkyl substances (PFAS) contamination associated with use of aqueous film forming foam (AFFF). The model was developed and calibrated by the U.S. Geological Survey (USGS) in cooperation with the U.S. Air Force Civil Engineer Center (AFCEC) based on the previously developed hydrogeologic framework (https://doi.org/10.3133/ofr20191134). Steady-state flow in the unconsolidated aquifers was simulated using the MODFLOW 6 which accounts...
A previously-developed groundwater model of the Suwannee River Basin was modified and calibrated to represent transient conditions. A simulation of recent conditions was developed for the 372-month period 1970-2000, and was compared with a simulation of future conditions for a similar-length period 2039-2069, which uses downscaled GCM (Global Climate Model) data. The MODFLOW groundwater-simulation code was used in both of these simulations, and two different MODFLOW boundary condition “packages” (River and Streamflow Routing Packages) were used to represent interactions between surface-water and groundwater features. The parameters for the simulation of future conditions were developed from dynamically downscaled...
The previously developed three-dimensional groundwater flow model (MODFLOW2000) of the Denver Basin bedrock aquifer system and overlying alluvial aquifer (https://pubs.er.usgs.gov/publication/pp1770 and model archive https://doi.org/10.5066/F77W69PQ) was updated to provide quantitative estimates of groundwater flow conditions and provide a useful tool for managers to analyze temporal changes to the hydrologic system in response to changing climatic conditions and future groundwater development. The computer program ZONEBUDGET was used to calculate cell by cell water balances for the major components of the water budget for the Upper Big Sandy Designated Groundwater Basin alluvial aquifer. The original Denver Basin...
A steady-state groundwater flow model, using MODFLOW-NWT, was developed to better understand groundwater flow in coastal Connecticut and adjacent areas of New York and Rhode Island. Aquatic systems in and around Long Island Sound (LIS) provide a variety of ecological and economic benefits such as flood and storm protection, water filtration, recreation, habitat for commercially and recreationally important fish and bird populations, and carbon sequestration. In some areas of LIS and in many embayments along the Connecticut coastline, aquatic ecosystems are degraded due to excess nitrogen from sources such as waste-water treatment plants, septic systems, and fertilizer. A substantial fraction of total nitrogen inputs...
A three-dimension groundwater-flow model (MODFLOW-2005) was developed to improve understanding of groundwater flow and pumping effects near the Long Canyon Mine in Goshute Valley, northeastern Nevada. Bulk hydraulic properties of carbonate rocks and basin-fill aquifers were characterized by simultaneously interpreting steady-state flow during predevelopment conditions and changes in groundwater levels and spring flows from the 2016 multiple-well aquifer test with an integrated groundwater-flow model. 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/sir20215021).
A modified version of SEAWAT was used in a study by the USGS and the Miami-Dade Water and Sewer Department to simulate effluent injection into the Boulder Zone and groundwater flow and effluent transport in the Floridan aquifer system. The Miami-Dade Water and Sewer Department injects nonhazardous, secondarily treated, domestic wastewater (effluent) into the Boulder Zone of the Floridan aquifer system at the North District Wastewater Treatment Plant, in southeastern Florida. Effluent injection into the Boulder Zone began in June 1997 and was first detected outside the Boulder Zone in the overlying Avon Park permeable zone in May 1998. The Department has detected injected effluent outside the Boulder Zone at six...
A three-dimensional, groundwater-flow model (MODFLOW-2005) was developed to estimate the hydraulic properties (e.g., transmissivity, hydraulic conductivity, specific yield, and specific storage) of volcanic rocks in Pahute Mesa, Nye County, Nevada. The model was calibrated using parameter estimation (PEST) by fitting estimated drawdowns to simulated drawdowns from 16 multiple-well aquifer tests. Water-level models were used to estimate drawdowns from continuous water-level data collected during multiple-well aquifer testing. This USGS data release contains all of the input and output files for the simulations described in the associated model documentation report (http://doi.org/10.3133/sir20165151). This data release...
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