Water Resource Management Commons^™

Harnessing Backcasting To Identify Drivers Of Critical Warming At Hoover Dam Using Hydrodynamic And Machine Learning Models, Eunice Ledres

UNLV Theses, Dissertations, Professional Papers, and Capstones

Elevated water temperatures can pose a significant threat to dam infrastructure, potentially damaging turbines, overheating internal components, and forcing generator shutdowns. This study uses a backcasting framework to evaluate how future scenarios may result in elevated water temperatures. Backcasting defines undesirable outcomes and works backward to identify the conditions that lead to them. The developed backcasting framework integrates 3D physics-based simulations with a Long-Short Term Memory (LSTM)surrogate model and SHapely Additive exPlanations (SHAP) interpretation. The combination captures temporal water temperature dynamics and quantifies the contributions of different drivers to elevated water temperature releases. As proof of concept, these methods are …

Shallow Groundwater Extraction Strategies In The Las Vegas Valley, Nevada, Teryl Stacey

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Las Vegas Valley faces severe water scarcity due to Nevada’s limited Colorado River allocation and an arid climate. Population growth and prolonged drought have intensified these constraints, necessitating alternative resource strategies. This project evaluated a strategy to make use of brackish, shallow groundwater (from the top 30 feet below ground surface) located in the central and east-central parts of the valley. Its objective was to extract lower quality shallow groundwater for use as an alternative to fresh water currently being used for some applications that require little to no treatment. Dust suppression is among the most promising of such …

Hot Spring Associated Infectious Diseases In The Great Basin And Southwest, Matthew Bentz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Like all bodies of freshwater, natural hot springs can harbor pathogenic microorganisms that carry the threat of infectious disease. The unique chemistry, increased temperature, and popularity for bathing may alter the risk profile of hot springs compared to other natural bodies of water. Despite this risk, the role of hot springs as a reservoir for infectious diseases remains understudied, particularly within the context of regional public health. Nevada and the Great Basin/Southwest have increasingly promoted hot springs for the purposes of tourism, and they share a strong link to the cultural heritage of the region. The unknown risk profile and …

Climate Change And Hydropower Development Impacts In The Lower Mekong Basin, Nudthawud Homtong

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Mekong River Basin is vital to East and Southeast Asia, supporting over 60 million people and sustaining critical ecological systems. However, the basin faces dual threats from climate change and hydropower development, jeopardizing its ecological balance, hydrological patterns, and resource reliability. This research focuses on the Lower Mekong Basin (LMB), where aggressive hydropower expansion and climate variability have intensified concerns about sustainable water management. The study is divided into three interconnected parts. Part I examines spatial and temporal precipitation patterns in the Chi-Mun Basin (CMB) and Lower Mekong River (LMR) from 1950 to 2008, using linear regression and Mann-Kendall …

Dry And Wet Deposition Of Atmospheric Microplastics In Las Vegas, Nevada, Laine Adame

UNLV Theses, Dissertations, Professional Papers, and Capstones

Plastics have been one of the most widely used man-made materials since their inception, and production is expected to grow by five percent every year. Plastic waste has become a growing global environmental issue. Primary MPs are plastics that are created to be intentionally tiny for their specific functional purpose. Secondary microplastics (MPs) are byproducts of plastic waste occurring due to the breakdown of larger plastics resulting in the presence and accumulation of MPs in the environment. MPs are defined as tiny particles of plastic between 5 mm and 1 μm in size. MPs have been found in the deep …

Uptake Of Contaminants Of Emerging Concerns (Cecs) By Plants Irrigated With Recycled Waters, Abid Hussain

UNLV Theses, Dissertations, Professional Papers, and Capstones

The increasing demand for water in arid and semi-arid regions necessitates the use of recycled water (RW) for irrigation. RW is a viable alternative to conventional irrigation water at most locations, but it can be a major route for contaminants of emerging concerns (CECs) to be taken up by the tissues of food crops, thereby leading to their subsequent entry into the food chain. CECs include pharmaceuticals, personal care products, and industrial chemicals that are generally present at low concentrations in environmental waters, hence their common designation as trace organic compounds (TOrCs), and CECs also include microbiological constituents such as …

Addressing Low Molecular Weight Chemical Peaking Events During Direct Potable Reuse By Granular And Biological Activated Carbon, Ceonie Washington

UNLV Theses, Dissertations, Professional Papers, and Capstones

Direct Potable Reuse (DPR) is an innovative solution designed to address water scarcity by treating wastewater to directly produce safe drinking water. As droughts and water shortages become more frequent, DPR offers a sustainable and localized water supply by incorporating advanced treatment processes. DPR systems typically rely on a combination of technologies such as ozone followed by biological activated carbon (O3/BAC), reverse osmosis (RO), and advanced oxidation processes (AOPs) to remove a wide range of contaminants. However, low molecular weight organic compounds (LMWCs), particularly volatile organic compounds, can sometimes pass through RO membranes and AOP systems.

California's DPR regulations currently …

Evaluation Of The Extent Of Floods In 2022 In Different Land Cover And Land Use Classes In Sindh Province, Pakistan Using Sentinel-1 And Sentinel-2 Imageries, Alina Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

Floods are one of the most frequent and most devastating natural disasters, which cause widespread destruction and pose significant risks to human life, infrastructure, and the environment. Advancement in remote sensing technologies and methodologies have demonstrated their efficacy in disaster-related applications, such as the detection, monitoring, and analysis of floods. This study explores the utilization of Synthetic Aperture Radar (SAR) and optical imagery for flood extent mapping and studying the extent of flood over various land cover and land use classes in Pakistan's Sindh province, utilizing the cloud computing power of Google Earth Engine. The change detection method identified extensive …

Investigating A Passive Treatment System For The Removal Of Nutrients From Urban Runoff, Jasminn Gray

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Environmental Protection Agency recognizes urban runoff as a major contributor of surface water pollution with nutrients as the second largest cause of surface water impairment in the United States. While a water quality standard of 100 lbs/day total phosphorus load allocation for all nonpoint sources is permitted for the Las Vegas Valley (LVV) under the National Pollutant Discharge Elimination System, currently there is not a counterpart standard for nitrogen. With the continued development of the LVV and the depletion of the quantity of water in Lake Mead due to the ongoing drought, the concentrations of phosphorus and nitrogen species …

Numerical Studies Of Regularized Navier-Stokes Equations And An Application Of A Run-To-Run Control Model For Membrane Filtration At A Large Urban Water Treatment Facility, Jeffrey Belding

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation consists of two parts. The first part consists of research on accurate and efficient turbulent fluid flow modeling via a family of regularizations of the Navier-Stokes equation which are known as Time Relaxation models. In the second part, we look into the modeling application for the filtration/backwash process at the River Mountains Water Treatment Facility in Henderson, NV.

In the first two chapters, we introduce the Time Relaxation models and their associated differential filter equations. In addition, we develop the regularization method which employs the Nth van Cittert deconvolution operator, which gives rise to the family of models. …

A 155-Year Tree-Ring Based Record Of Warm And Dry Snow Droughts For The Cascade Range, Usa, Laura A. Dye

UNLV Theses, Dissertations, Professional Papers, and Capstones

Contributing 50-80% to the surface water for the region, mountain snowpack is a pillar of the hydrologic cycle in the western US, and is projected to decrease to 44% by 2100 in the Cascade Mountains alone. The western US has recently been identified as a global snow drought hot spot, exhibiting more frequent, intensified, and lengthened snow drought events in recent decades. Only recently has the need to understand the types of snow droughts and their driving mechanisms become critical to understand and quantify. Recent research suggests ‘warm’ snow droughts caused by winter precipitation falling as rain rather than snow …

Degradation Of Antibiotics In Aqueous Phase Using Pms Catalytic Decomposition With Zero-Valent Iron Nanoparticles Immobilized In Sba-15, Ahdee Bluma Zeidman

UNLV Theses, Dissertations, Professional Papers, and Capstones

Zero-valent iron nanoparticles (nZVI) have been studied as an option for soil remediation and water treatment for many years. The capability of nZVI to produce oxidation/reduction processes, depending on the reaction conditions, has attracted great interest with their major drawback being reactivity loss through agglomeration. The loss in nZVI surface area has been reported to be prevented through immobilization onto a porous media (e.g., SBA-15, MCM-41, or zeolites). In this work, a mesoporous silica structure (SBA-15) is used as an nZVI supporting material to enhance its reactivity and promote peroxymonosulfate (PMS) catalytic decomposition for the degradation of antibiotics in aqueous …

Estimation Of Spatial Change In Cropland Area And Evaluation Of Irrigation Performance In Imperial Valley Using Remotely Sensed Data, Usha Poudel

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Imperial Valley (IV) in the US is an extensively irrigated agricultural region, which includes multiple crops changing on an annual and semiannual basis. The valley is facing grave concerns about water management due to its semi-arid environment, water intensive crops, and limited water supply. A simple, inexpensive, and repeatable method to detect changes in cropping patterns may assist irrigation managers to understand crop diversification and associated consumptive use. In addition, a spatial assessment of existing water irrigation system performance and productivity is crucial to benchmark and improve current water management strategies. This thesis estimates the spatial pattern of change …

A Fusion Of Remotely Sensed Data To Map The Impervious Surfaces Of Growing Cities Of Punjab, Pakistan, Binita Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

Urban population is expected to exceed 70% of the world’s total by the middle of the 21st century. Thus, growth in number as well as the sizes of the cities are certain in the near future. The urbanization rates will be much higher in the developing countries than the developed. Such phenomena are accompanied by conversion of land cover from its natural use to built up environment to accommodation growing population. Built up surfaces include road networks, buildings, parking lots and pathways. They are permanently impervious and hydrologically active surfaces. Large volume and discharges of runoff characterize impervious surfaces with …

Carbon Management And Volatile Fatty Acid Production In Primary Clarifiers At A Wastewater Treatment Plant, Brittany Nicole Radke

UNLV Theses, Dissertations, Professional Papers, and Capstones

An increasing number of treatment plants are required to remove nutrients from domestic wastewater to lessen the impact of nutrient loading to water bodies. Enhanced Biological Phosphorus Removal (EBPR) is one of the processes commonly used to remove phosphorus from domestic wastewater. The presence of an adequate quantity of volatile fatty acids (VFA) in the wastewater influent to EBPR is important for process efficiency and stability. The objective of this research was to investigate the production of VFAs through fermentation of sludge in primary clarifiers as it related to improving nutrient removal, primarily targeting phosphorus.

The research tested, in full-scale, …

Application Of Data-Driven And Process-Based Modeling Approaches For Water Quality Simulation In Lakes And Freshwater Reservoirs, Ali Saber Sichani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lakes and freshwater reservoirs often serve as the primary drinking and irrigation water sources for surrounding communities. They provide recreational and tourism opportunities, thereby promoting the prosperity of neighboring communities. Reliable estimates of water quality in lakes and reservoirs can improve management practices to protect water resources.

Seasonal water temperature and solar shortwave radiation variations, and their subsequent interactions with water column aquatic life, combined with seasonal variations of mixing intensity throughout the water column, result in variations of water quality constituents with depth during the annual cycle. The complexity of these variations entails the use of advanced water quality …

Application Of Semi-Hydrophobic Layers To Decrease Bare Soil Evaporation, Jesse Lee Barnes

UNLV Theses, Dissertations, Professional Papers, and Capstones

Evaporative water loss from bare agricultural soils is a primary area of water conservation research. Mulching is the commonly utilized method to decrease evaporative water loss. The most commonly utilized mulch is nonbiodegradable polyethylene sheeting because it tends to decrease evaporative water loss and increase crop yields more than environmentally friendly mulches. This study aimed to test the utility of sand coated with polymerized soybean oil (i.e., hydrophobic sand) as a treatment to reduce bare soil evaporation and an alternative to current practices. Evaporation rates were measured in laboratory soil columns containing both treated and untreated soils. Treatment parameters were …

Utilization Of Remote Sensing Data For Estimation Of The Groundwater Storage Variation, Gaurang Mistry

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater is the most extracted raw material, with an average withdrawal rate of 982 km3 per year, where 70 percent of the total groundwater withdrawn is used for agriculture globally (Margat & van der Gun, 2013). With climate change and increased water demands in recent years, monitoring the changes in the groundwater storage is of the utmost importance. This thesis presents an analysis that determines the rates, trends, and directions where groundwater storage is going in Pakistan. It also correlates fluctuations in groundwater storage with variations in precipitation and agricultural productivity in the country. The overall objectives of this thesis …

Static And Dynamic Quantitative Microbial Risk Assessment Of Potable Reuse Paradigms, Erfaneh Amoueyan

UNLV Theses, Dissertations, Professional Papers, and Capstones

In recent years, potable reuse applications have become more common due to population growth and increased water demand, especially in communities with limited or variable water resources. However, there are concerns about potential exposure to pathogens and chemical compounds in treated wastewater. Therefore, advanced wastewater treatment processes are of paramount importance in any potable reuse system. The overall aim of this study was to develop and implement static and dynamic QMRAs to compare public health risk in various potable reuse scenarios. Cryptosporidium, norovirus, adenovirus, and Salmonella were chosen as the target pathogens. The research evaluated the performance of full advanced …

Hexavalent Chromium Removal From Residual Ion-Exchange Brine Using Ferrous Sulfate, Ana Luiza De Araujo Silva

UNLV Theses, Dissertations, Professional Papers, and Capstones

Removal of hexavalent chromium (Cr(VI)) from water and wastewater is required for health purposes and regulation compliance. Among the technologies available, ion exchange (IX) has been extensively applied and, in most cases, is followed by resin regeneration for the purpose of cost optimization. However, resin regeneration produces residual IX brine, also called waste regenerant brine, which is considered hazardous for containing the contaminant(s) treated in the column. This research focuses on the use of ferrous sulfate (FeSO4) to reduce and precipitate Cr(VI) contained in the regenerant brine from IX resins. The Cr(VI) reduction to trivalent chromium (Cr(III)) occurs due to …

Estimation And Comparison Of Thermoelectric And Pv Solar Water Usage In The Colorado River Basin States, Yuzhen Feng

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the continual expansion of populations in the arid Southwest, energy demands will continue to rise. On the other hand, depleting water levels in reservoirs of the Colorado River Basin is expected to continue as more intense and frequent drought events persist in addition to the rapid development in the region. Currently, the three largest water-use categories in the United States are thermoelectric energy, irrigation, and municipal water, which cumulatively account for 90 percent of the national water use. In the Southwest, most of the total electricity generated is still through thermoelectric means. That is, massive amounts of water are …

From Access To Excess: Agribusiness, Federal Water Programs, And The Historical Roots Of The California Water Crisis, Tracy Marie Neblina

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this paper is to show the link between water use, land consolidation, agribusinesses, and the water crisis that California began to experience in 2011. In order to better understand the relationship between the growth of agribusiness in the state and the evolution of water policy, this paper explores the historical context of land policy, the growth of farming in the San Joaquin Valley, and the development of federally funded water projects in the Central Valley. Years of expanding farmland and use of surface and underground water with limited regulation played an important role in exacerbating California’s water …

Water Source Partitioning For Shrubland Transpiration In A Mixed Phreatophytic Plant Community, Amanda Jean Wagner

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater in the basins of east central Nevada (Great Basin Desert, NV) has been permitted for export to southern Nevada. These basins are also vulnerable to changes in climate that could lead to declining recharge. Any decline in groundwater levels no matter the driving force could significantly impact phreatophytes (deep rooted shrubs), which utilize water from both the vadose zone and the capillary fringe to meet plant water needs, to support growth, and for overall health. A reduction in groundwater due to these forces could have a significant impact on the decoupling of phreatophytes from what is normally a reliable …

Estimating Aquifer Characteristics And Identification Of A Sub-Basin For Artificial Storage And Recovery, Northeastern Ivanpah Valley, Nevada, Nikolas James Taranik

UNLV Theses, Dissertations, Professional Papers, and Capstones

The identification of a structurally controlled sub-basin with impediments to groundwater flow within Southern Nevada could provide a favorable area for artificial recharge and storage of native or imported water, extending the water supply of Southern Nevada. For this purpose, the area of northeastern Ivanpah Valley was investigated to determine the ability of the aquifer to accept and recover stored water, if acceptable water quality existed in the potential sub-basin storage area, and if structural controls impeded and isolated groundwater flow. The results found evidence the proposed sub-basin is structurally isolated by the McCullough, Roach, and Stateline Faults, which was …

Survival, Growth, And Settlement Of Dreissena Rostriformis Bugensis Veligers In Low And High Calcium Waters, Emma Ruhmann

UNLV Theses, Dissertations, Professional Papers, and Capstones

Populations ofDreissena rostriformis bugensis(quagga mussels) have continued to spread throughout the western United States since their discovery in the Boulder Basin of Lake Mead, NV-AZ in early 2007. Today, quagga mussel specific research is still lacking and the physicochemical characteristics of aquatic systems required by quagga mussels to successfully establish is not fully understood. This includes an absence of research in aquatic environments in the western United States and on quagga mussel veligers (larval stage). Calcium is considered the defining factor for determining if a lake or river is suitable for quagga mussel establishment. The minimum calcium threshold for invasion …

Understanding Selenium Distribution In Lake Mead Using A Three-Dimensional Hydrodynamic Based Water Quality Model, Xiaolu Wei

UNLV Theses, Dissertations, Professional Papers, and Capstones

Shallow groundwater and surface drainages in Las Vegas Wash are known to have elevated level of selenium which mainly comes from the naturally occurring geological hotspots on the southeast side of the Las Vegas Valley. Selenium fate and transport after it enters into Lake Mead from the Las Vegas Wash are not clearly understood. An open sourced three-dimensional Environmental Fluid Dynamic Code model (EFDC), developed by the United States Environmental Protection Agency, was used to model movement of selenium in the Boulder Basin, Lake Mead. The model was calibrated by observed data from 2006 to 2007. The concept of Lagrangian …

Using Seismic Reflection To Locate A Tracer Testing Complex South Of Yucca Mountain, Nye County, Nevada, Levi Kryder

UNLV Theses, Dissertations, Professional Papers, and Capstones

Tracer testing in the fractured volcanic aquifer near Yucca Mountain, and in the alluvial aquifer south of Yucca Mountain, Nevada has been conducted in the past to determine the flow and transport properties of groundwater in those geologic units. However, no tracer testing has been conducted across the alluvium/volcanic interface. This thesis documents the investigative process and subsequent analysis and interpretations used to identify a location suitable for installation of a tracer testing complex, near existing Nye County wells south of Yucca Mountain.

The work involved evaluation of existing geologic data, collection of wellbore seismic data, and a detailed surface …

Evaluation Of Alternative Project Delivery Methods In Water And Wastewater Projects, Ruiko Maharjan

UNLV Theses, Dissertations, Professional Papers, and Capstones

The United States (U.S.) is facing significant challenges in addressing aging water infrastructure. Most of the drinking water infrastructure is reaching the end of their useful lives. The American Water Works Association (AWWA) estimated that it will cost about $1 trillion to repair or replace drinking water pipes. Over the next 20 years, it will cost about $298 billion to fix or expand pipes of the nation's wastewater and storm-water systems (AWWA, 2012). Owners, engineers, and contractors are using Alternative Project Delivery (APD) methods - e.g., Design-Build Construction Management-at-Risk Construction Management/General Contractor- to build water and wastewater projects in order …

Phosphorus Removal From Ebpr Sludge Dewatering Liquors Using Lanthanum Chloride, Aluminum Sulfate And Ferric Chloride, Michael Strileski

UNLV Theses, Dissertations, Professional Papers, and Capstones

In wastewater treatment, enhanced biological phosphorus removal (EBPR) is becoming an increasingly popular alternative to chemical precipitation (CP) because of its lower costs and reduced sludge production. However, downstream solids handling processes such as digestion, sludge storage and dewatering promote an undesirable release (i.e. secondary release) of polyphosphate that was stored within EBPR sludge. Released phosphate is recycled to the head of the plant with the liquors of sludge dewatering processes. The concentration of phosphate in recycle streams from EBPR systems can be one to two orders of magnitude higher than the influent phosphorus concentration entering the EBPR system. Plants …

Understanding Basin Specific Life History Characteristics Of Lake Mead Quagga Mussels (Dreissena Bugensis) And A Potential Treatment Using Uv Radiation In Laboratory Studies, Melissa Thaw

UNLV Theses, Dissertations, Professional Papers, and Capstones

The quagga mussel (Dreissena bugensis) is an aquatic invasive species that is spreading throughout Lake Mead and other western waterways. Unlike their native waters in Eurasia, Lake Mead exhibits year round warm temperatures, high calcium levels and a lack of natural predators, all of which are very favorable conditions for their growth and spread. Dreissena bugensis reproduce and colonize hard surfaces rapidly, where they filter large amounts of water. They disrupt the aquatic food chain and interfere with infrastructure that is exposed to lake water. There is an urgent need to understand Dreissena bugensis life history characteristics within this new …