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Groundwater

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Full-Text Articles in Hydrology

Shallow Groundwater Distributions And Changes With Sea Level Rise In Seattle, Washington, Taylor L. Watson Dec 2023

Shallow Groundwater Distributions And Changes With Sea Level Rise In Seattle, Washington, Taylor L. Watson

Graduate Theses and Dissertations

Sea level rise (SLR) associated hazards, such as coastal flooding and erosion, are pressing issues of great concern for coastal communities across the globe. Shallow and emergent groundwater can contribute to groundwater hazards such as flooding, landslides, or damage to shallow infrastructure. This study investigates the shallow groundwater within Seattle, Washington, and projects how it will respond to SLR using interpolation and numerical groundwater modeling methods. Then, a geologic modeling method is presented as a preliminary investigation of heterogeneity and anisotropy within the aquifer system. In the results for the present-day interpolation, ~6 % of the coastal buffer –the total …


Modeling Overdraft-Driven Nitrate Transport In Shallow Wells For Mitigation And Scenario Planning, Jonathan Cronk Nov 2023

Modeling Overdraft-Driven Nitrate Transport In Shallow Wells For Mitigation And Scenario Planning, Jonathan Cronk

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

In Nebraska, average nitrate concentrations in groundwater have doubled since 1974, making water quality management more important than ever. As droughts, heat waves, and floods become more common climate events, understanding their impacts will be necessary to make informed management decisions. Emerging literature describes that drought correlates to an increase in the concentration of nitrate-N at domestic and irrigation wells, however the relative contributions of the mechanisms thought to be responsible is currently unknown.

This research assessed the impact of recharge and pumping rate changes as two mechanisms affecting nitrate-N concentration during drought, assessed the relationship between well depth and …


Factors Affecting Groundwater Nitrate Concentration In Madinah Area, Saudi Arabia, Majed M. Almutairi Apr 2023

Factors Affecting Groundwater Nitrate Concentration In Madinah Area, Saudi Arabia, Majed M. Almutairi

Masters Theses

High levels of nitrate in groundwater are a serious problem in Madinah Area, Saudi Arabia. Identifying factors affecting groundwater nitrate contamination is important for managing groundwater quality. This study examined factors that have significant impacts on the high level of groundwater nitrate in Madinah Area. Factors examined included well-depth and land cover. Relationships between variables were explored using three statistical approaches: the Kruskal-Wallis test and two types of regression (ordinary least squares [OLS] and geographically weighted regression [GWR]).

Nitrate concentration data show that 73% of obtained groundwater samples exceeded the United States Environmental Protection Agency (EPA) maximum contaminant level (MCL) …


Importance Of Snowmelt On Soil Nitrate Leaching To Groundwater – A Model Study, Sahila Beegum, Arindam Malakar, Chittaranjan Ray, Daniel D. Snow Feb 2023

Importance Of Snowmelt On Soil Nitrate Leaching To Groundwater – A Model Study, Sahila Beegum, Arindam Malakar, Chittaranjan Ray, Daniel D. Snow

Nebraska Water Center: Faculty Publications

The movement of nitrate to surface water bodies during snow accumulation and melting has been extensively studied, but there are only limited studies on the influence of snow processes on nitrate leaching to groundwater. The present study investigated the impact of snow processes on nitrate leaching to groundwater based on a simulation modeling approach using HYDRUS-1D. HYDRUS-1D model has a temperature threshold-based snow model in addition to water, solute, and heat simulation components. The snow component in HYDRUS-1D was previously not applied to snow simulation studies since the method does not consider a detailed physical and process-based representation of snow …


Estimating Evapotranspiration And Analyzing Soil Moisture And Heat Flux Parameters At Taneum Creek, Central Washington, Edward Vlasenko Jan 2023

Estimating Evapotranspiration And Analyzing Soil Moisture And Heat Flux Parameters At Taneum Creek, Central Washington, Edward Vlasenko

All Master's Theses

In the past two decades, stream restoration work, primarily in the form of wood emplacement, has been undertaken in the Taneum Creek watershed, resulting in increased channel-floodplain connectivity. One of the goals of stream restoration was to boost dry season groundwater storage in the shallow floodplain aquifer. However, any gains in groundwater due to increased connectivity may be nullified by increased evapotranspiration (ET) losses because of denser floodplain vegetation. Within the floodplain aquifer budget, ET is a major flow of water out of the system and is not well quantified.

In order to quantify ET, a monitoring site was established …


Evaluating The Sensitivity Of Crustal Deformation To Bedrock Hydrology In A Mountain Watershed, Brett J. Oliver Jan 2023

Evaluating The Sensitivity Of Crustal Deformation To Bedrock Hydrology In A Mountain Watershed, Brett J. Oliver

Graduate Student Theses, Dissertations, & Professional Papers

We evaluate the sensitivity of Earth's elastic deformation to groundwater hydraulic diffusivity using coupled groundwater and elastic deformation models. Seasonal changes in terrestrial water storage cause deformation to the Earth’s crust and deeper interior that is within the observational capacity of GPS instruments. We couple finite difference groundwater simulations with geodetic forward models of crustal displacement to investigate the ability of geodetic deformation to constrain bedrock hydrologic properties. We use MODFLOW-2005 to simulate seasonal changes in groundwater flow and storage, and then use the LoadDef elastic deformation model to forward model surface displacement caused by the change in terrestrial water …


Effects Of Salix Psammophila On Groundwater Recharge In A Semiarid Area Of North China, Lizhu Hou, Jingdong Gao, Bill X. Hu, Xixi Wang Jan 2023

Effects Of Salix Psammophila On Groundwater Recharge In A Semiarid Area Of North China, Lizhu Hou, Jingdong Gao, Bill X. Hu, Xixi Wang

Civil & Environmental Engineering Faculty Publications

Study region: The semiarid Mu Us Sandy Land (MUSL) was selected for this study. It is in the farming-pastoral ecotone of north China and functions as an eco-environmental barrier.

Study focus: Afforestation can mitigate desertification and soil erosion by improving hydrologic condition, which is particularly true for semiarid and arid regions. However, little is known about the quantitative response of hydrologic improvement to afforestation level that can be measured by leaf area index (LAI). The objective was to setup and use a physically-based model to quantitatively assess the dynamics of water fluxes from Salix psammophila afforestation in the MUSL.

New …


Hydrologic Modeling With Remote Sensing For The Estimation Of Groundwater Resources Within The Sand River Catchment, South Africa, Sophia Bakar Dec 2022

Hydrologic Modeling With Remote Sensing For The Estimation Of Groundwater Resources Within The Sand River Catchment, South Africa, Sophia Bakar

Electronic Theses and Dissertations

The Sand River Catchment is an important tributary of the transboundary Limpopo River in South Africa, which spans Botswana, Mozambique, South Africa, and Mozambique. Groundwater is a critical resource in the region, especially in the context of population growth and climate change. Data are needed for proper management of these water resources. In regions where groundwater data are sparse in time, space, or both, the most promising solutions come from satellites and hydrologic models. Regional literature suggests that the Soutpansberg Mountains, located within the Sand Catchment, are high-elevation water towers with uncertain groundwater resources. Improved understanding of groundwater resources in …


Patterns Of Dissolved Methane In Groundwater And Its Contribution To Emissions Inventories, Amanda E. Campbell Jul 2022

Patterns Of Dissolved Methane In Groundwater And Its Contribution To Emissions Inventories, Amanda E. Campbell

Dissertations - ALL

The Marcellus Shale is the largest shale gas play in the U.S. production of natural gas using high-volume hydraulic fracturing (HVHF) and production is prevalent throughout the play except in New York (NY), where it is currently banned. High concentrations of methane, the main component of natural gas, in groundwater, as well as its presence in the atmosphere, can have negative consequences. In this dissertation, three aspects of this issue are explored: 1) how and why naturally-occurring methane concentrations vary through time; 2) how elevated naturally-occurring methane concentrations in domestic water wells can be predicted from commonly observed well characteristics; …


Groundwater Monitoring Analysis And Management Recommendations In California: Cuyama And Santa Cruz Mid-County, Kayla M. Souza May 2022

Groundwater Monitoring Analysis And Management Recommendations In California: Cuyama And Santa Cruz Mid-County, Kayla M. Souza

Master's Projects and Capstones

Groundwater is an essential water resource, accounting for about 40 percent of supply in California and 80 percent in the Central Coast hydrologic region, but significant monitoring data gaps have limited sustainable management efforts. Twenty-four basins within the Central Coast hydrologic region were identified as critically overdrafted in 2014. For this study, two basins were chosen based on differing sustainability concerns so that a comparative analysis could be performed on the groundwater monitoring methods. I obtained original groundwater elevation data reported (2000-2020) from the various groundwater monitoring organization wells to the California Department of Water Resources (DWR) within the Cuyama …


Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano May 2022

Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano

All Theses

Toxoplasma gondii is a pathogenic microorganism that is currently a threat to public health. Understanding the fate and transport of T. gondii through the soil and groundwater is vital in determining the risk it poses to water resources and human health. The physico-chemical interactions between the groundwater and the bio colloid within an aquifer will dictate its mobility and its ability to infect humans. This research examines how various naturally occurring groundwater chemistries containing organic compounds and monovalent and divalent salt solutions will alter the fate and transport of T. gondii. Solutions containing various concentrations of humic acid, fulvic …


Surface Water/Groundwater Interactions And Hydrogeochemical Characterization Of The Elkhorn Mine And Mill, Beaverhead County, Montana, Tyler Kamp Apr 2022

Surface Water/Groundwater Interactions And Hydrogeochemical Characterization Of The Elkhorn Mine And Mill, Beaverhead County, Montana, Tyler Kamp

Graduate Theses & Non-Theses

The formation of acid mine drainage (AMD) and the contaminants associated with it have been described by some as the largest environmental problem facing the U.S. mining industry. Heavy metals associated with the drainage, such as copper, cadmium, and zinc affect the water quality of streams and can cause acute or chronic toxicity to invertebrates and fish (Martin, 1992& Padrillah et al., 2018). Elkhorn Creek in the Pioneer Mountains of southwest Montana is one of these impacted creeks. The historic Elkhorn Mine and Mill complex has historically attributed to the creek’s contamination and has undergone remediation. However, the problem has …


Groundwater Modeling Of The West Plains, Wa, Erin L. Toulou, Chad Pritchard Phd, Lauren Stachowiak Phd Apr 2022

Groundwater Modeling Of The West Plains, Wa, Erin L. Toulou, Chad Pritchard Phd, Lauren Stachowiak Phd

2022 Symposium

Located in Eastern Washington in the West Plains Region sits a plateau of Columbia River Basalts between Deep Creek, Hangman Creek, and south of the Spokane River. Primarily in Airway Heights, the amount of drinking water as well as the quality of the water has affected residents in the area. The most recent issue is PFAS contamination, which is thought to negatively affect human health and is found in drinking water wells across the West Plains. We can interpret subsurface geology using new well logs from Fairchild Air Force Base and in the Palisades area. When using ArcGIS PRO, well …


Arsenic In Groundwater Sources From Selected Communities Surrounding Taal Volcano, Philippines: An Exploratory Study, Geminn Louis C. Apostol, Sary Valenzuela, Xerxes Seposo Mar 2022

Arsenic In Groundwater Sources From Selected Communities Surrounding Taal Volcano, Philippines: An Exploratory Study, Geminn Louis C. Apostol, Sary Valenzuela, Xerxes Seposo

Ateneo School of Medicine and Public Health Publications

Arsenic (As) is a highly toxic, carcinogenic trace metal that can potentially contaminate groundwater sources in volcanic regions. This study provides the first comparative documentation of As concentrations in groundwater in a volcano-sedimentary region in the Philippines. Matched, repeated As measurements and physico-chemical analyses were performed in 26 individual wells from 11 municipalities and city in Batangas province from July 2020 to November 2021. Using the electrothermal atomic absorption spectrometric method, analysis of the wells revealed that in 2020, 23 out of 26 (88.46%) had As levels above the WHO limit of >10 ppb while 20 out of 26 wells …


Baseflow And Water Resilience Variability In Two Water Management Units In Southeastern Brazil, Lucas Vituri Santarosa, Didier Gastmans, Troy E. Gilmore, Jan Boll, Sebastian Balbin Betancur, Vitor Fidelis Monteiro Gonçalves Jan 2022

Baseflow And Water Resilience Variability In Two Water Management Units In Southeastern Brazil, Lucas Vituri Santarosa, Didier Gastmans, Troy E. Gilmore, Jan Boll, Sebastian Balbin Betancur, Vitor Fidelis Monteiro Gonçalves

Conservation and Survey Division: Faculty and Staff Publications

Changes in climate and water demand in densely populated regions increasingly affect hydrological systems, and, in turn, impact socioeconomic conditions. In this case study, we identify how the hydrogeological frameworks of two water resource management units, Tietê-Jacaré (TJ) and Piracicaba-Capivari-Jundiaí (PCJ) in Sao Paulo state (Brazil), control the baseflow processes and resilience in the face of streamflow fluctuations in response to anthropogenic activities and climate variation. The results reveal between 40% and 75% contributions of baseflow to total streamflow in basins overlying crystalline and sedimentary aquifers. The basins in PCJ which mostly overly crystalline aquifers, have shorter water residence times …


Impact Of Type And Shape On The Transport Of Microplastics In Column Experiments, Cheyanne Amanda Schenkel Jan 2022

Impact Of Type And Shape On The Transport Of Microplastics In Column Experiments, Cheyanne Amanda Schenkel

Graduate Research Theses & Dissertations

The pervasive nature of plastic and the longevity of plastic compounds leaves a legacy of plastics and microplastics (MPs) that contaminate our environment, including drinking water sources. Although MPs have been well documented in every environmental setting, a paucity of research has focused on the transport and fate of MPs in groundwater systems. Previous field and lab studies have shown that MPs can migrate through aquifer material and that their retention and retardation are influenced by changing environmental factors. This study used coarse, well-sorted sand in controlled column experiments to investigate the influence of polymer type (PA, PE, PP, PEST) …


Assessing The Effects Of Instream Large Wood On Floodplain Aquifer Recharge And Storage At Indian Creek, Kittitas County, Washington, Usa, Stephen Bartlett Jan 2022

Assessing The Effects Of Instream Large Wood On Floodplain Aquifer Recharge And Storage At Indian Creek, Kittitas County, Washington, Usa, Stephen Bartlett

All Master's Theses

Numerous stream restoration projects in the Yakima River Basin in Washington have placed large wood (LW) into tributary channels. One intended effect is to divert water onto floodplains to increase groundwater (GW) recharge and seasonal storage in shallow alluvial aquifers during spring high flows with the intention of releasing GW into streams during the drier summer months. Large wood was emplaced in the Indian Creek tributary of the Teanaway River in Kittitas County, Washington beginning in 2016. Potential changes in the groundwater recharge in the adjacent floodplain before and after the LW installation were investigated through stratigraphic analysis, stream-flow modeling, …


Climate Change Impacts On Baseflow Contributions In A Semi-Arid, Snowmelt-Dominated Basin Within The Upper Colorado River Basin, Kaelyn Quinlan Jan 2022

Climate Change Impacts On Baseflow Contributions In A Semi-Arid, Snowmelt-Dominated Basin Within The Upper Colorado River Basin, Kaelyn Quinlan

Graduate Research Theses & Dissertations

The Upper Colorado River Basin (UCRB) is a significant water resource in the southwestern United States, providing water to Colorado, New Mexico, Utah, and Wyoming. (Reclamation, 2012). Communities and industries within these states are dependent on the Colorado River’s water availability and accessibility. Growing population and development demands, in conjunction with climate change, can have drastic consequences for the ecosystems and municipalities dependent on these reservoirs. It is critical that as watersheds within this region are strained under increased demands and decreased inputs, water use practices use informed decision-making to manage the budget and quality of its water resources.

I …


Source Apportionment And Health Risk Assessment Of Nitrate In Foothill Aquifers Of Western Ghats, South India, Banajarani Panda, S. Chidambaram, Daniel D. Snow, Arindam Malakar, Dhiraj Kr Singh, L. Ramanathan Dec 2021

Source Apportionment And Health Risk Assessment Of Nitrate In Foothill Aquifers Of Western Ghats, South India, Banajarani Panda, S. Chidambaram, Daniel D. Snow, Arindam Malakar, Dhiraj Kr Singh, L. Ramanathan

Nebraska Water Center: Faculty Publications

The present research reports the level of nitrate (NO3-), associated health risks and possible sources of contamination in groundwater from south India. Many samples (32%) are above or approaching the recommended level of NO3- for safe drinking water. The correlation analysis indicates different sources of NO3- contamination in different regions rather than a common origin. The isotopic measurements provide information about potential nitrogen sources contributing NO3- to the groundwater. Based on isotope analysis, the sources of NO3- in the groundwater of this region are likely to be from (a) …


The Importance Of Monitoring To Assess The Impact Of Climate Change On Groundwater Resources In Bangladesh, Muhammad Qumrul Hassan, Anwar Zahid, Nazrul I. Khandaker Oct 2021

The Importance Of Monitoring To Assess The Impact Of Climate Change On Groundwater Resources In Bangladesh, Muhammad Qumrul Hassan, Anwar Zahid, Nazrul I. Khandaker

Publications and Research

Groundwater is the major source of fresh water across much of the world, but there has been very little study on the impacts of climate change on this precious and finite resource. Rising levels of greenhouse gases are likely to increase the global average surface temperature over the next 100 years, raise sea levels and reduce soil moisture. The amount of water stored in the soil is fundamentally important to agriculture and influences the rate of actual evaporation, groundwater recharge and runoff. Rising sea levels would cause the tidal saltwater wedge to intrude further upstream in rivers, with resulting changes …


Statistical Analysis Of Groundwater Level Fluctuation Of The Urban And Peri-Urban Area Of Gazipur District, Bangladesh, Nowshin Ahsan Priyanka, Atika Rahman Akji, Anwar Zahid, Muhammad Qumrul Hassan, Jowaher Raza, Nazrul I. Khandaker Oct 2021

Statistical Analysis Of Groundwater Level Fluctuation Of The Urban And Peri-Urban Area Of Gazipur District, Bangladesh, Nowshin Ahsan Priyanka, Atika Rahman Akji, Anwar Zahid, Muhammad Qumrul Hassan, Jowaher Raza, Nazrul I. Khandaker

Publications and Research

Groundwater is the primary source for drinking, municipal, irrigation, and industrial water supply in Bangladesh. Due to unplanned urbanization and rapidly growing industries, the degradation situation has become perilous over time. Dhaka and its peri-urban regions are having drastic changes in groundwater (GW) levels. This work reviewed GW level fluctuation in the peri-urban area, which is now severely experiencing the detrimental impact of rapid urbanization and industrialization. Detail statistical investigation and Landsat image interpretation of the study area was conducted. Analysis and prediction of water level trends were conducted using variations of Mann Kendell tests. Gazipur Sadar (an upazila or …


An Adaptive Hazard Planning And Mitigation Framework For Responding To Urban Contamination In Karst Aquifer Systems, James Edward Troxell Oct 2021

An Adaptive Hazard Planning And Mitigation Framework For Responding To Urban Contamination In Karst Aquifer Systems, James Edward Troxell

Masters Theses & Specialist Projects

Environmental hazards in karst regions are damaging and often go unnoticed until an issue has escalated to a point of affecting life or property. The field of emergency and environmental contamination response lacks planning or preparedness focused on remediating groundwater contamination in karst systems. A lack of preplanning before an incident can lead to confusion, delayed response, and the inability to remediate the contaminant. Due to the rapid movement of contaminants through urban karst groundwater aquifers, an efficient response plan that leverages localized data in a GIS should be developed and maintained in order to adequately respond. The objective of …


Hydrogeophysical Investigation For The Aquifers In Part Of Ilorin, Central Nigeria: Implication On Groundwater Prospect, Ayodele Kehinde Olawuyi May 2021

Hydrogeophysical Investigation For The Aquifers In Part Of Ilorin, Central Nigeria: Implication On Groundwater Prospect, Ayodele Kehinde Olawuyi

Tanzania Journal of Science

Hydrogeophysical study involving the use of Vertical Electrical Sounding (VES) was carried out in part of the basement complex rocks of Ilorin, central Nigeria, with the aim of determining its geoelectric parameters and groundwater potential. A total of thirty (30) VES were carried out using Schlumberger electrode configuration, with half electrode separation (AB/2) varying from 1m to 100m. Information on the subsurface lithologies, overburden thickness and aquiferous layers were obtained from the different VES locations in the study area. From the quantitative interpretations of the data collected, using the method of curve matching with the Orellana-Mooney master curves and 1-D …


Desktop Review Of Groundwater Prospectivity For Irrigation In The Lower De Grey River Area, Don L. Bennett, John A. Simons Mar 2021

Desktop Review Of Groundwater Prospectivity For Irrigation In The Lower De Grey River Area, Don L. Bennett, John A. Simons

Resource management technical reports

The Department of Primary Industries and Regional Development (DPIRD) has identified priority areas in the Pilbara that warrant further investigation into their capacity for irrigated agriculture and related businesses. The De Grey River area is one of these.

The lower De Grey River area, upstream of the De Grey River Water Reserve, was identified by the Transforming Agriculture in the Pilbara (TAP) project for staged investigations of viability. Progression through these stages, each with increasingly detailed groundwater and soil suitability investigations, is dependent on prospectivity.

This document provides a summary of DPIRD’s initial desktop groundwater evaluation in the lower De …


Nebraska Statewide Groundwater-Level Monitoring Report 2020, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel Feb 2021

Nebraska Statewide Groundwater-Level Monitoring Report 2020, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel

Conservation and Survey Division: Faculty and Staff Publications

The term “groundwater” has come to be all but synonymous with Nebraska. Nearly three-quarters of the total volume of the High Plains Aquifer lies beneath the state. Groundwater maintains our streams, our ecosystems, our people, and our vitally important agricultural economy. Nebraska’s total groundwater resource is vast, yet it is also vulnerable to natural and anthropogenic changes, necessitating a long-term commitment to wise management through informed decision-making. Monitoring, studying, and reporting form the essential basis for such management and, ultimately, for meeting the myriad challenges presented by change.


Nitrogen Dynamics And Transport Along Flowpaths In A Rural Wetland-Stream Complex, Colton Kyro Jan 2021

Nitrogen Dynamics And Transport Along Flowpaths In A Rural Wetland-Stream Complex, Colton Kyro

Graduate Student Theses, Dissertations, & Professional Papers

Human activities have doubled the rate of nitrogen inputs onto the landscape resulting in elevated nitrogen concentrations in our streams. Anthropogenically applied nitrogen is largely transported to stream networks via groundwater movement. Groundwater discharge occurs in distinct points along a stream but whose influences can often persist far beyond that area due to insufficient biogeochemical removal of imported nitrogen potentially causing alterations in community structure and precipitating large algae blooms. To understand the factors governing nitrogen abundance in a historical polluted stream, I used a mass-balance approach to quantify groundwater-surface water interaction and the magnitude of groundwater nitrogen input and …


Baseflow Nitrate Dynamics Within Nested Watersheds Of An Agricultural Stream In Nebraska, Usa, Galen Richards, Troy E. Gilmore, Aaron R. Mittelstet, Tiffany Messer, Daniel D. Snow Jan 2021

Baseflow Nitrate Dynamics Within Nested Watersheds Of An Agricultural Stream In Nebraska, Usa, Galen Richards, Troy E. Gilmore, Aaron R. Mittelstet, Tiffany Messer, Daniel D. Snow

Daugherty Water for Food Global Institute: Faculty Publications

There is a need to evaluate high surface nitrate concentrations across agricultural watersheds, both spatially and temporally, to increase understanding of source and timing of nitrogen loads in streams and rivers. Bazile Creek is a high-nitrate stream originating in the agriculturally intensive Bazile Groundwater Management Area of Eastern Nebraska, USA. It is a gaining stream that receives groundwater with high nitrate concentrations originating from nonpoint sources. The objective of this study was to determine spatial and temporal variability of baseflow nitrate concentrations in Bazile Creek and its tributaries and to relate this variability to watershed characteristics. Surface-water nitrate samples were …


Quantifying Bedrock Recharge In Two Paired Mountainous Watersheds, Kimberly Bolhuis Jan 2021

Quantifying Bedrock Recharge In Two Paired Mountainous Watersheds, Kimberly Bolhuis

Graduate Student Theses, Dissertations, & Professional Papers

This study focuses on 1) estimating the magnitude of bedrock recharge and 2) mean transit time as a function of bedrock permeability in two paired catchments underlain by different lithology. Networks of bedrock wells and stream gauges were installed in two adjacent catchments of approximately the same size in west central Montana. Fracture network properties for both lithologies were characterized from borehole core logging and scan lines on exposed outcrop. Recharge was evaluated using the Water Table Fluctuation (WTF) method on bedrock well hydrographs installed in both catchments. Stable water isotope samples, collected approximately monthly, from precipitation and stream water …


Climate Change Impacts Go Beyond The Surface: Groundwater Recharge Rates And Aquifer Resources Across The Contiguous United States, Kendra R. Devereux Jan 2021

Climate Change Impacts Go Beyond The Surface: Groundwater Recharge Rates And Aquifer Resources Across The Contiguous United States, Kendra R. Devereux

Senior Independent Study Theses

Groundwater is a primary source of potable water for millions and a major source for crop irrigation in the United States. Thus, it is vital to understand current and future rates of recharge to predict and manage groundwater availability. In this study, current groundwater recharge rates across the Contiguous US at 800m resolution are estimated by following methods presented by Reitz et al. (2017), and the reproducibility of the methods are assessed. A water budget approach is implemented where quick flow runoff and evapotranspiration rates are subtracted from precipitation rates. Precipitation was found to be the most reproducible water budget …


Response Of Deep Aquifers To Climate Variability, Karem Fathy Abdelgaber Abdelmohsen Dec 2020

Response Of Deep Aquifers To Climate Variability, Karem Fathy Abdelgaber Abdelmohsen

Dissertations

Our recent analysis of Temporal Gravity Recovery and Climate Experiment (GRACE) solutions over the largest aquifer system in Africa (the Nubian Sandstone Aquifer System: NSAS) revealed that while the response of deep aquifers to climatic variations remains a relatively slow process that takes thousands to tens of thousands of years, there is a much faster response in aquifers that are characterized by dense networks of faults, fractures and karst as is the case with the NSAS. This rapid groundwater flow, when it occurs, is detected as an increase in GRACETWS over areas downgradient and distant (hundreds of km) from …