Digital Commons Network^™

Groundwater Flow Across The Coyote Wash Fault And Cedar Mesa Anticline Near St. Johns, Arizona, Stephanie Lynn Latour

Theses and Dissertations

As the demand for water increases across the southwestern United States, the region's utilization of and dependence on water stored in groundwater aquifers has risen in kind. The Coconino Aquifer (C-aquifer) underlies much of the southwestern Colorado Plateau and is a primary source of groundwater in northeastern Arizona. One of the largest commercial users of water from the C-aquifer in Apache County, Arizona, is Springerville Generating Station, a coal-fired power plant owned and operated by Tucson Electric Power. The area surrounding the power plant, located between the cities of Springerville and St. Johns, Arizona (the Springerville-St. Johns area), is geologically …

Groundwater Flow And Salt Marsh Migration: The Forest/Marsh Boundary, Camille Rossiello

Theses and Dissertations

Salt marshes migrate landward in response to sea level rise, but the rate of this migration is not constant and can be influenced by pulse disturbances. Long term observations at Sapelo Island, Georgia, show that salt marsh migration has occurred during droughts, but the mechanism for this migration is unclear. Drought is thought to influence salt marsh migration by reducing fresh groundwater discharge from the upland. Rising sea level also encroaches on the upland, which could cause movement of the freshwater lens inland. A two-dimensional numerical model was built to simulate groundwater flow and solute transport based on the Marsh …

Assessment Of Spatial And Temporal Variations In Chloride Concentration In An Agricultural Tile-Drained Area In Central Illinois, Okiemute Commander

Theses and Dissertations

Long-term increase in chloride (Cl-) concentration in surface water and groundwater from anthropogenic sources, including deicing salts, agriculture, septic effluents, and wastewater treatment plants is a growing cause for concern all over the world. In rural midwestern US with predominant agricultural land usage and less impervious surface cover, agriculture may serve as a potential source for Cl- in surface and groundwater systems. A saturated riparian buffer (SRB) installed adjacent to a central Illinois stream to reduce nutrient losses was used to identify populations of Cl-, substantiate agricultural influence, and identify spatial and temporal Cl- variations within the SRB. 2297 water …

Evaluation Of A Radium-Thorium Disequilibrium Sediment Method Used To Model And Assess Porewater And Submarine Groundwater Exchange In The Coastal Marsh, Madeline R. Bodine

Theses and Dissertations

Ground, pore, and surface water exchange has been extensively studied in beach and near shore environments but has been long neglected in saltmarsh systems due to their complexity. Saltmarsh systems are of particular importance as they are the interface between fresh and saltwater. Saltmarshes impact carbon exchange, release and sequestration, and they process particulate matter. Understanding the characteristics of a marsh system such as the nutrient and particulate loads in conjunction with the flux of water exchange through the marsh provides a deeper understanding of these systems and can impact our understanding of the global water and carbon cycles, as …

Multi-Year Analysis Of Groundwater Temperature Fluctuations In A Shallow Aquifer Sysytem Influenced By A Tile-Drain, Jack Thomas Wassik

Theses and Dissertations

Groundwater temperature plays a significant role in regulating geochemical, biological and physical processes with the subsurface with wide ranging environmental and societal impacts. Air temperature, weather conditions and lithology exhibit control on magnitude and timing of thermal responses that ultimately control groundwater temperature. Historical groundwater, tile water, stream and air temperature data from the T3 site were analyzed, including groundwater temperature data from multiple depths was analyzed. Additionally, statistical analyses between the temperature datasets were performed in order to interpret potential relationships. Air temperature was found to be the primary control of groundwater temperatures, though its affect being muted as …

Applied Machine Learning In Development Of Geospatial Information Tools For Sustainable Groundwater Management, Saul Gallegos Ramirez

Theses and Dissertations

Groundwater plays an important role in sustainable water resource management. Globally, the development of groundwater resources for irrigation provides a stable water source and enhances food security. However, developing groundwater resources is difficult, requiring the collection, synthesis, analysis, and dissemination of information about groundwater in an accessible, effective manner so decision makers have the knowledge and tools to implement sustainable management strategies. In this dissertation, I present solutions to assist with the paucity of groundwater data. The first problem I explore is extending the Palmer Drought Severity Index to near present day. This dataset is crucial to current groundwater imputation …

An Analysis Of Groundwater Storage Loss In The Central Valley Using A Novel In Situ Method Compared To Grace-Derived Results, Michael David Stevens

Theses and Dissertations

Robust groundwater management is necessary to maintain long-term aquifer sustainability. Temporally and spatially inconsistent in situ data prevents robust groundwater resource evaluation. Data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission has been used to evaluate long-term, large-scale groundwater trends. However, the spatial resolution of GRACE data presents challenges for groundwater management in medium-sized aquifers like the Central Valley of California (CV). Other researchers have utilized GRACEderived data to evaluate groundwater storage in the CV, but they often make corrections due to what is referred to as the "leakage effect." We demonstrate a method for imputing gaps in …

Methods For Characterizing Groundwater Resources With Sparse In-Situ Data, Ren Nishimura

Theses and Dissertations

Groundwater water resources must be accurately characterized in order to be managed sustainably. Due to the cost to install monitoring wells and challenges in collecting and managing in-situ data, groundwater data is sparse in space and time especially in developing countries. In this study we analyzed long-term groundwater storage changes with limited times-series data where each well had only one groundwater measurement in time. We developed methods to synthetically create times-series groundwater table elevation (WTE) by clustering wells with uniform grid and k-means-constrained clustering and creating pseudo wells. Pseudo wells with the WTE values from the cluster-member wells were temporally …

Baseflow Variability Due To Changes In Climate, Basin Characteristics, And Groundwater Withdrawals In The State Of Wisconsin, Usa, Susan Borchardt

Theses and Dissertations

ABSTRACT

BASEFLOW VARIABILITY DUE TO CHANGES IN CLIMATE,BASIN CHARACTERISTICS, AND GROUNDWATER WITHDRAWALS IN THE STATE OF WISCONSIN, USA

bySusan Borchardt The University of Wisconsin-Milwaukee, 2022 Under the Supervision of Professor Woonsup Choi

In Wisconsin, the number of high-capacity wells has increased substantially, and concerns have been raised about their impact on both groundwater levels and streamflow. At the same time Wisconsin’s climate has been changing, and both the annual precipitation (5%) and temperature (1.5oC) have been trending upward over the last 68 years and both are predicted to increase into the future. This study attempted to demonstrate the simultaneous effects …

Groundwater Flow And Transport At The Forest-Marsh Boundary: A Modeling Study, Sophia Chason Sanders

Theses and Dissertations

The forest-marsh boundary, where tidally influenced salt marshes meet a forested upland, is hydrologically complex due to its multiple water inputs. Groundwater flow and salinity transport at this boundary are not well understood. In order to make predictions about salinity at this boundary as it responds to climatic factors, a two-dimensional model was built to simulate groundwater flow and solute transport at a salt marsh on Sapelo Island, Georgia. After calibration based on observed data from wells at the study site, the model can be used to identify patterns in groundwater movement and solute transport that may influence the vegetation …

Analysis Of Surface Water For Irrigation In The Big Sunflower River Watershed, Meredith Lynn Brock

Theses and Dissertations

Exploitation of groundwater and excess nutrient runoff are major issues plaguing agriculture and streams in the Lower Mississippi River Basin, and increased irrigation intensity has yielded a proportionate increase in water use. Quantifying the use and effects of conservation practices like on-farm water storage (OFWS) systems will justify continued adoption of these practices to mitigate groundwater decline and nutrient runoff. Since 2010, over 795 hectares of surface water storage has been added in the Big Sunflower River Watershed, and analysis of aquifer saturation shows a recent rise in the water table and a decrease in seasonal water table drawdowns. Modeling …

Water Chemistry And Lake Dynamics Of Laguna Bacalar, Quintana Roo, Mexico, Ryan Matzuk

Theses and Dissertations

Laguna Bacalar in the Quintana Roo region is the second largest lake in Mexico and contains freshwater derived solely from groundwater. Local geology on the Yucatan Peninsula is karstic and the southern shoreline of Laguna Bacalar is spotted with a handful of cenotes that contribute substantial amounts of inflowing groundwater to the lake. This is shown by sonde profile data taken in one of the largest cenotes in the area. Outflow is dominated by a surface water outlet in the southern portion of the lake and an unknown amount of outflowing groundwater. During January of 2017 through 2019, UWM researchers …

An Open-Source Web-Application For Regional Analysis Of Grace Groundwater Data And Engaging Stakeholders In Groundwater Management, Travis Clinton Mcstraw

Theses and Dissertations

Since 2002, NASA's GRACE Satellite mission has allowed scientists of various disciplines to analyze and map the changes in Earth's total water storage on a global scale. Although the raw data is available to the public, the process of viewing, manipulating, and analyzing the GRACE data can be difficult for those without strong technological backgrounds in programming or geospatial software. This is particularly true for water managers in developing countries, where GRACE data could be a valuable asset for sustainable water resource management. To address this problem, I have a developed a utility for subsetting GRACE data to particular regions …

Groundwater Level Mapping Tool: Development Of A Web Application To Effectively Characterize Groundwater Resources, Steven William Evans

Theses and Dissertations

Groundwater is used worldwide as a major source for agricultural irrigation, industrial processes, mining, and drinking water. An accurate understanding of groundwater levels and trends is essential for decision makers to effectively manage groundwater resources throughout an aquifer, ensuring its sustainable development and usage. Unfortunately, groundwater is one of the most challenging and expensive water resources to characterize, quantify, and monitor on a regional basis. Data, though present, are often limited or sporadic, and are generally not used to their full potential to aid decision makers in their groundwater management.This thesis presents a solution to this under-utilization of available data …

Geospatial Analyses Of Groundwater Depletion And Contamination: Multiscale - Global, Regional And Local Analyses, Aynaz Lotfata

Theses and Dissertations

The overarching objective of this dissertation was to study groundwater resources on global, local, and regional scales. The first objective of this dissertation was to analyze the groundwater nitrate contamination in the Edwards-Trinity and the Southern High-Plains aquifers of Texas. The second was to study groundwater quality in terms of seawater intrusion in the California Coastal Basin, Upper Floridian, and North Atlantic Coastal Plain aquifers. This dissertation also provided a comprehensive overview of the groundwater level in basins at the global scale and further analyzed agricultural activities on groundwater storage in small and large basins. To achieve first objective, Ordinary …

Capture Zone Analysis Of A Wellfield To Assess Contaminant Transport, Prince Kojo Oware

Theses and Dissertations

Radium is a common contaminant to the deep Cambrian- Ordovician aquifer in northern Illinois. Deep groundwater aquifers are used as fresh water resource in many parts of the world. Due to overuse, increase in salinity, natural and human-driven contamination, sustainability of these aquifer systems is uncertain. The purpose of this study is to better understand the groundwater flow system in deep bedrock aquifers in northern Illinois, and its control on the radium contamination in Rochelle’s Public Water Supply Wells (PWSW). We have tested two hypotheses: (1) the Radium (Ra) transport is driven by large pumping centers that interrupt groundwater flow …

Hydrogeologic Characteristics And Groundwater Sustainability Of A Deep Bedrock Aquifer System In Illinois, Luis Martinez

Theses and Dissertations

Population growth and climate change has made groundwater an increasingly important freshwater resource. This study uses MODFLOW to estimate sustainable yield of a deep St. Peter Aquifer in Bloomington, IL. The city of Bloomington has installed two high capacity wells into the St. Peter Sandstone to meet its growing water demands. The St. Peter Aquifer is confined, receiving almost no modern recharge and is experiencing overexploitation in parts of Northern Illinois. I hypothesize that existing fast depletion of the deep St. Peter occurs due to lower-than-expected aquifer parameters of the aquifer. Further, current pumping of groundwater from the St. Peter, …

Groundwater Quality Assessment Of The Piney Point Aquifer In The Virginia Coastal Plain, Elizabeth J. Keily

Theses and Dissertations

The solid phase of an aquifer has an effect on the aqueous phase; if groundwater quality is degraded by the solid phase of an aquifer this is referred to as geogenic pollution. In this study, the Piney Point aquifer in the Virginia Coastal Plain was assessed for mechanisms that may release anions from the solid to aqueous phases and effect water quality. This was done by conducting leaching experiments modified from Balintova et al. (2013). Piney Point aquifer sediments and groundwaters were also analyzed to give a baseline for these experiments. Sedimentary analysis was found to be consistent with McFarland …

Diurnal And Seasonal Variation In Groundwater Nitrate -N Concentration In A Saturated Buffer Zone, Joseph Miller

Theses and Dissertations

Surface water pollution by nitrate (NO3-) is identified as a critical problem in agricultural land-use areas. Excess NO3- loading causes eutrophication and hypoxia in near-shore marine waters such as the Gulf of Mexico. Diversion of agricultural runoff into saturated buffer zones reduces NO3- loading. Although the mechanisms responsible for NO3- reduction in saturated buffer zones are well characterized, little is known about how NO3- concentrations vary temporally and what factors control those changes. The objective of this study is to understand NO3- concentration and environmental factor variability in a saturated buffer zone on a diurnal scale within and among the …

Dynamics Of Chemical Degradation In Water Using Photocatalytic Reactions In An Ultraviolet Light Emitting Diode Reactor, John E. Stubbs

Theses and Dissertations

This work examined ultraviolet (UV) light emitting diodes (LED) and hydrogen peroxide in an advanced oxidation process in support of a USAF installation net zero water initiative. A UV LED reactor was used for degradation of soluble organic chemicals. There were linear relationships between input drive current, optical output power, and first order degradation rate constants. When drive current was varied, first order degradation rates depended on chemical identities and the drive current. When molar peroxide ratios were varied, kinetic profiles revealed peroxide-limited or radical-scavenged phenomena. Molar absorptivity helped explain the complexity of chemical removal profiles. Degradation kinetics were used …

Phosphorus Occurrence And Origin In The Mississippi River Valley Alluvial Aquifer In Northwestern Mississippi, Claire Elise Rose

Theses and Dissertations

The median total dissolved phosphorus concentration (0.41 mg/L P) of groundwater from the Mississippi River Valley alluvial aquifer exceeded the U.S. Environmental Protection Agency’s stream nutrient criteria (of 0.1 mg/L P) and the national background for phosphorus in groundwater (0.02 mg/L P). A general association between elevated phosphorus and dissolved iron concentrations suggests that reducing conditions that mobilize iron in the aquifer also may facilitate transport of phosphorus. These elevated concentrations of phosphorus may indicate phosphorus in the study area may be concentrated through irrigation return flow and groundwater discharge, and may contribute to the Gulf of Mexico hypoxic zone. …

Cloud-Based Analytic Element Groundwater Modeling, Jacob Baird Fullerton

Theses and Dissertations

Managing groundwater resources requires computer modeling software, which in turn brings its own costs in education and usage fees. Although many groundwater modeling programs can be obtained at relatively inexpensive rates the hidden costs of software training remain high in general. What has been done is to make both the software and training available online for free, but this method delegates all responsibility to the users for both accessing the software in addition to learning how to use it properly. In this research the accessibility of groundwater models has been improved upon by creating a web app of an open …

Methodology To Predict Daily Groundwater Levels By The Implementation Of Machine Learning And Crop Models, Sandra Milena Guzman Gutierrez

Theses and Dissertations

The continuous decline of groundwater levels caused by variations in climatic conditions and crop water demands is an increased concern for the agricultural community. It is necessary to understand the factors that control these changes in groundwater levels so that we can better address declines and develop improved conservation practices that will lead to a more sustainable use of water. In this study, two machine learning techniques namely support vector regression (SVR) and the nonlinear autoregressive with exogenous inputs (NARX) neural network were implemented to predict daily groundwater levels in a well located in the Mississippi Delta Region (MDR). Results …

Ecohydrology And Groundwater Dynamics In A Salt Marsh Island, Andrea L. H. Hughes

Theses and Dissertations

Tidal salt marshes are extraordinarily productive and valuable ecosystems that provide via groundwater a not insignificant portion of coastal solute and nutrient budgets. Among the many goods and services they provide are habitat for diverse wildlife, protection for coastal communities during storms, and protection for coastal surface waters by filtering anthropogenic pollutants. One threat to the health of tidal salt marshes along the East Coast have been episodes of Acute Marsh Dieback (AMD) from 1999 to 2001. Dieback was observed at North Inlet salt marsh from 2000 to 2001. Since salt marsh hydrology is dominated by the local tidal regime, …

An Examination Of The Hydrological Environment In Choctaw County Mississippi Since 1995, With A Focus On An Area Surrounding An Industrial Complex Established In 1998, Jeremy Keith Foote

Theses and Dissertations

The population and industrial complexes of Choctaw County obtains much of its water from an aquifer system in the Tertiary age Wilcox unit of the Mississippi Embayment. Utilizing 20 years of physical chemistry (P-Chem) analysis, potentiometric groundwater records of Choctaw County public water wells as well as industrial P-Chem analysis and surface and ground water level records from an industrial complex, this study examined the changes to the hydrosphere that has taken place since 1995. Analysis of the hydrosphere shows that over the last 20 years, there has been a drop in the potentiometric surface of the Wilcox aquifer system. …

High Capacity Wells And Baseflow Decline In The Wolf River Basin, Northeastern Wisconsin, Susan A. Borchardt

Theses and Dissertations

The baseflow of the Wolf River (drainage area of 1 200 km2) in northeastern Wisconsin has declined by over 30% during the last thirty years, whereas climatic, land cover, and soil characteristics of the basin have remained unchanged. Because groundwater basins do not always coincide with surface water basins, estimating groundwater discharge to streams using variables only pertinent to the surface water basin can be ineffective. The purpose of this study is to explain the decline in the baseflow of the Wolf River by developing a multiple regression model. To take into account variables pertaining to the groundwater basin, withdrawal …

Transport Of Potential Microbial Source Tracking Markers In Sandy Material, Jennifer J. Johanson

Theses and Dissertations

ABSTRACT

TRANSPORT OF POTENTIAL MICROBIAL SOURCE TRACKING MARKERS IN SANDY MATERIALS

by

Jennifer J. Johanson

The University of Wisconsin-Milwaukee 2016

Under the Supervision of Professor Shangping Xu

Groundwater, a primary source of drinking water for nearly half the people in the United States, can be contaminated by pathogenic bacteria from fecal materials causing outbreaks of waterborne illness. Therefore, early identification of the presence of fecal contamination in groundwater can help prevent such outbreaks, and determining whether bacteria originate from human or animal feces can narrow down the location of potential pollution sources, allowing timely remediation and reduced potential for future …

Trace Element Inputs From Natural And Anthropogenic Sources In An Agricultural Watershed, Middle Provo River, Utah, Timothy Holman Goodsell

Theses and Dissertations

Water chemistry in rivers is impacted by a variety of natural and anthropogenic processes including agricultural runoff, urban runoff, storm runoff, groundwater inputs, and the built environment. In this study we used trace element concentrations (including As, B, Ce, Co, Cu, Li, Mn, Rb, Sb, Sr, Tl, V, and Zn) and continuous measurements of flow rates and specific conductance to investigate dynamic processes affecting water quality in a rapidly urbanizing agricultural area typical of the western U.S. The middle Provo River, located in northern Utah, USA, was selected as the study area because it is well instrumented with water quality …

Surface-Water And Groundwater Interactions Of A Stream Reach And Proposed Reservoir Within The Pascagoula River Basin: George County, Mississippi, Courtney Killian

Theses and Dissertations

This research had two main objectives: quantify surface-water and groundwater interactions along a stream reach, and determine the hydraulic conductivity at the site where two reservoirs are proposed. The objectives of this research aim to help maintain stream ecology and increase surface water storage for recreational and industrial purposes. The stream reach, located in the Pascagoula River Basin of southeast Mississippi, begins at Lake Okatibbee and terminates at Pascagoula into the Gulf of Mexico. Four USGS continuous gauging stations provided more than forty years of stream discharge data for a hydrograph baselow-recession analysis, which determined the baseflow component within the …

Model Of Residence Time And Analysis Of Nitrogen Removal For Two Constructed Wetlands At The Franklin Demonstration Farm In Lexington, Illinois, Emma Singh Baghel

Theses and Dissertations

Pollution from nonpoint agricultural runoff has become a major problem facing our streams and rivers today. Not only are fish and aquatic life affected, but so is the quality of our drinking and recreational water resources. Studies have shown that wetlands have proven to be the most cost-effective and low maintenance method of removing nonpoint or diffused contaminate inputs. The biological processes and removal of nutrients in wetlands depend on the total surface area available for microbial activity in the soil and a certain period of water retention time. Since chemical processes take time, the measure of residence time is …