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Full-Text Articles in Engineering

Exploratory Data-Driven Models For Water Quality: A Case Study For Tampa Bay Water, Sandra Sekyere Jun 2023

Exploratory Data-Driven Models For Water Quality: A Case Study For Tampa Bay Water, Sandra Sekyere

USF Tampa Graduate Theses and Dissertations

Water, a crucial resource for sustaining life, covers approximately 70% of the earth's surface. Nonetheless, the quality of water is deteriorating rapidly due to the rapid growth of urban areas and industries, which is a worrying trend causing harm to human health and the ecosystem. Water quality forecasting has a key role in water resources management by enabling effective pollution control, ecosystem monitoring, and decision-making.

Previously, traditional statistical models were used to forecast water quality, but they were unable to examine the non-linear relationships between water quality parameters, and they assumed that all datasets were distributed normally. This study uses …


Characteristics And Hydraulic Behavior Of Adsorptive Media For Use In Permeable Reactive Barriers, Shelby Rocha Jun 2023

Characteristics And Hydraulic Behavior Of Adsorptive Media For Use In Permeable Reactive Barriers, Shelby Rocha

USF Tampa Graduate Theses and Dissertations

The Cargill ditch is located on the property of Se7en Wetlands, a 1600-ac treatment wetland system in Lakeland, Polk County, Florida. The Se7en Wetlands property was previously utilized for phosphate mining prior to the construction of the system. Nonpoint nutrient sources derived from remnants of abandoned phosphate mines – known as “legacy phosphorus” – become mobilized by stormwater runoff and impair surface water bodies by promoting harmful algal blooms (HABs). Thus, the Cargill ditch likely conveys nutrient rich flow resulting from legacy phosphorus and is thought to be one contributing factor in the occurrence of HABs within the treatment wetland …


Quantifying A 21-Year Surface Water And Groundwater Interaction In A Ridge And Valley Lake Environment Using A Highly Constrained Modeling Approach, Richard T. Bowers Jr. Nov 2022

Quantifying A 21-Year Surface Water And Groundwater Interaction In A Ridge And Valley Lake Environment Using A Highly Constrained Modeling Approach, Richard T. Bowers Jr.

USF Tampa Graduate Theses and Dissertations

Karst lakes are ubiquitous in ridge terrain settings in limestone aquifer coastal plain environments. In west-central Florida, these lakes are frequently connected to the Upper Floridan aquifer and have unique aquifer recharge characteristics. They have been selectively studied because they commonly have no or very limited surface water discharge and limited drainage areas, have appreciable surface water and groundwater interaction and leak to the deep aquifer. An innovative modeling approach was developed to collectively understand and more precisely quantify this vertical leakage, both from a lake-specific and regional water budget standpoint, for a 21-year study period (2000-2020). A unique, calibrated …


Pressure Retarded Osmosis: A Potential Technology For Seawater Desalination Energy Recovery And Concentrate Management, Joshua Benjamin Nov 2021

Pressure Retarded Osmosis: A Potential Technology For Seawater Desalination Energy Recovery And Concentrate Management, Joshua Benjamin

USF Tampa Graduate Theses and Dissertations

Currently, a significant challenge with reverse osmosis-based desalination is reducing the energy consumption and environmental impacts of the process. This project analyzed the viability of using pressure-retarded osmosis (PRO) for energy recovery in seawater desalination facilities using brine concentrate (the draw solution) and other water sources (the feed solution) such as wastewater effluent. The primary goal of this project is to decrease the cost and overall energy consumption of seawater desalination through PRO-based energy recovery. Process modeling, statistical and sensitivity analysis, energy and cost analysis, geospatial and GIS analysis, laboratory-scale testing, water quality analysis, SEM-EDS microscopy, computational fluid dynamics (CFD), …


A System Architecture For Water Distribution Networks, Noha Abdel-Mottaleb Nov 2021

A System Architecture For Water Distribution Networks, Noha Abdel-Mottaleb

USF Tampa Graduate Theses and Dissertations

This dissertation examines structure-function relationships of water distribution networks (WDNs), with focus on improving the decision-making process for water utilities. WDNs are lifeline infrastructure systems, necessary for the functioning of cities. Yet water utilities around the world struggle with emerging challenges that include but are not limited to aging infrastructure components, limited budgets, increased interdependencies between infrastructure systems, increased rates of urbanization, and increasing extreme weather conditions. This is why enhancing the performance of WDNs is a priority for water utilities around the world. This research begins to delineate a system architecture for WDNs and evaluates the use of various …


Socio-Technical Transitions In The Water Sector: Emerging Boundaries For Utility Resilience In Barbados, Wainella N. Isaacs Jul 2020

Socio-Technical Transitions In The Water Sector: Emerging Boundaries For Utility Resilience In Barbados, Wainella N. Isaacs

USF Tampa Graduate Theses and Dissertations

Resilience is gaining popularity in the water sector where it described as contributing to reduced vulnerability to water-related risks and hazards including climate change. Unfortunately, literature in this area, contributed mainly from North America and Europe, is fragmented with a concentration on engineering resilience in water supply infrastructure. The absence of any scholarship on resilience for a small island nation, coupled with the absence of sociological contributors to building resilience in this sector motivated this research.

The goal of this research was to understand and evaluate how resilience is characterized and operationalized in the Barbados water and wastewater infrastructure system, …


Structural And Agricultural Value At Risk In Florida From Flooding During Hurricane Irma, Alexander J. Miller Jun 2020

Structural And Agricultural Value At Risk In Florida From Flooding During Hurricane Irma, Alexander J. Miller

USF Tampa Graduate Theses and Dissertations

Flooding is the most costly type of natural disaster, as well as the most frequent. To provide risk-based flood insurance, providers such as FEMA must be able to accurately determine an asset’s risk of flooding. Additionally, after a flooding event, providers need to quickly determine the direct damages that occurred to verify insurance claims and provide assistance to the affected communities. Many current approaches to flood risk and flood damage estimation involve the use of data or statistical extrapolation that can add various sources of uncertainty into the final damage estimate. In order to reduce uncertainties in flood risk analyses, …


A Decision-Making Framework For Hybrid Resource Recovery Oriented Wastewater Systems, Nader Rezaei Jun 2019

A Decision-Making Framework For Hybrid Resource Recovery Oriented Wastewater Systems, Nader Rezaei

USF Tampa Graduate Theses and Dissertations

Water shortage, water contamination, and the emerging challenges in sustainable water resources management (e.g., the likely impacts of climate change and population growth) necessitate adopting a reverse logistics approach, which is the process of moving wastewater from its typical final destination back to the water supply chain for reuse purposes. This practice not only reduces the negative impacts of wastewater on the environment, but also provides an alternative to withdrawal from natural water resources, forming a closed-loop water supply chain. However, the design of such a supply chain requires an appropriate sustainability assessment, which simultaneously accounts for economic, environmental, and …


Prioritizing Rehabilitation Of Sanitary Sewers In Pinellas County, Fl, Jesse T. Hillman Jun 2019

Prioritizing Rehabilitation Of Sanitary Sewers In Pinellas County, Fl, Jesse T. Hillman

USF Tampa Graduate Theses and Dissertations

Following large rain events, extraneous freshwater contributions known as inflow and infiltration (I/I) bypass the storm sewer and enter the sanitary sewer system. In areas with a high water table, like Pinellas County and the surrounding Tampa Bay area, a majority of the wastewater infrastructure is submerged year round exacerbating the rate of groundwater infiltration. This excess flow overloads the existing wastewater infrastructure leading to sanitary sewer overflows (SSOs). These SSOs result in serious problems for municipalities and utilities across the country.

This study was performed in order to assist Pinellas County Utilities in rehabilitating their southern sewer system. To …


An Analytical Solution For Attainment Of Field Capacity, Ali Aldrees Nov 2018

An Analytical Solution For Attainment Of Field Capacity, Ali Aldrees

USF Tampa Graduate Theses and Dissertations

Field Capacity (FC) is a key parameter to quantify in agricultural engineering, irrigation controlling, and soil physics studies. For instance, irrigation studies focuses on determining the optimal amount of water needed by plants to grow following an irrigation system and therefore relies on determining FC. Likewise, the value of FC is a good indicator of soil textures, structures and pore size distributions. For example, loamy soils have a wider distribution of pores leading to high FC values. FC depends on multiple physically-grounded variables which include matric potential value (ψ_FC ), water content at FC (θ_FC ), specific drainage time to …


Recovery Of Nutrients From Anaerobically Digested Enhanced Biological Phosphorus Removal (Ebpr) Sludge Through Struvite Precipitation, Maraida Balaguer-Barbosa Oct 2018

Recovery Of Nutrients From Anaerobically Digested Enhanced Biological Phosphorus Removal (Ebpr) Sludge Through Struvite Precipitation, Maraida Balaguer-Barbosa

USF Tampa Graduate Theses and Dissertations

Water resources in Florida have been severely degraded by eutrophic conditions, resulting toxic algae blooms, which negatively affect health and tourism. Eutrophication, or excessive amount of phosphorus (P) and nitrogen (N) in water, overstimulates the production of aquatic plants, depletes dissolved oxygen, and deteriorates the aquatic environment. However, phosphorus is a non-renewable resource essential for all living organisms. In fact, more than half of the total demand for P globally is to supply the food industry, which has concerningly accelerated the depletion rates of phosphate reserves.

In many wastewater treatment plants (WWTPs), the enhanced biological phosphorus removal (EBPR) approach has …


Validating The Accuracy Of Neatwork, A Rural Gravity Fed Water Distribution System Design Program, Using Field Data In The Comarca Ngöbe-Bugle, Panama, Maria Briones Jul 2018

Validating The Accuracy Of Neatwork, A Rural Gravity Fed Water Distribution System Design Program, Using Field Data In The Comarca Ngöbe-Bugle, Panama, Maria Briones

USF Tampa Graduate Theses and Dissertations

Despite the sustainable development goals to increase access to improved water there are still 884 million people in the world without access to an improved water source (WHO, 2017). One method to improve access to water in rural, mountainous areas, is through construction of gravity fed water distribution systems. These systems should be designed based upon fundamental principles of hydraulics. One method of doing so in a time efficient manner with minimal engineering knowledge is to utilize a downloadable computer program such as Neatwork, which aids in design of rural, gravity fed water distribution systems and has been used by …


Underground Stormwater Treatment Performance In Urban Coastal Catchments: Case Study Of Baffle Boxes In The City Of Tampa, Awet Eyob Tsegay Jun 2018

Underground Stormwater Treatment Performance In Urban Coastal Catchments: Case Study Of Baffle Boxes In The City Of Tampa, Awet Eyob Tsegay

USF Tampa Graduate Theses and Dissertations

In coastal urban regions, underground stormwater treatment units are suitable infrastructure options because they take less space where premium land is expensive. Even then, they should be accessible and ideally small enough to fit into existing stormwater networks. Since 2003, the City of Tampa and Florida’s Department of Transportation (FDOT) have installed 47 baffle boxes into the city’s stormwater pipe networks. Baffle boxes are underground stormwater treatment structures designed to capture sediments and floating debris. Since their deployment, many challenges regarding their practical sediment capturing performance was raised by the city.

The objective of this research was to evaluate the …


Dynamic Modeling Of An Advanced Wastewater Treatment Plant, Komal Rathore Jun 2018

Dynamic Modeling Of An Advanced Wastewater Treatment Plant, Komal Rathore

USF Tampa Graduate Theses and Dissertations

Advanced wastewater treatment plants have complex biological kinetics, time variant influent rates and long processing times. The modeling and operation control of wastewater treatment plant gets complicated due to these characteristics. However, a robust operational system for a wastewater treatment plant is necessary to increase the efficiency of the plant, reduce energy cost and achieve environmental discharge limits. These discharge limits are set by the National Pollutant Discharge Elimination System (NPDES) for municipal and industrial wastewater treatment plants to limit the amount of nutrients being discharged into the aquatic systems.

This document summarizes the research to develop a supervisory operational …


Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca Mar 2018

Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca

USF Tampa Graduate Theses and Dissertations

Reliable access to safe drinking water is one necessity for humans to live without concern for major health risks. The overall goal of this research is to improve the public health, through improved drinking water, for communities in the Rakai District in Uganda, directly, and other communities in the world, indirectly, via dissemination of knowledge. This study specifically assessed the knowledge of drinking water quality in regards to public health, their sanitation measures, and water treatment methods for users of Brick by Brick rainwater harvesting tanks in the Rakai District (N = 28) by using a knowledge, attitudes, and practice …


Assessing The Impacts Of Climate Change On Streamflow And Reservoir Operation In Central Florida, Toni Panaou Jan 2018

Assessing The Impacts Of Climate Change On Streamflow And Reservoir Operation In Central Florida, Toni Panaou

USF Tampa Graduate Theses and Dissertations

Climate change is a global concern as it may affect many aspects of life, including water supply. A tool used to model climate change’s impacts is called a General Circulation Model (GCM). GCMs project future scenarios including temperature and precipitation, but these are designed at a coarse resolution and require downscaling for employment for regional hydrologic modeling. There is a vast amount of research on downscaling and bias-correcting GCMs data, but it is unknown whether these techniques alter precipitation signals embedded in these models or reproduce climate states that are viable for water resource planning and management. Using the Tampa, …


Quantifying And Modeling Surface Inflow And Groundwater Infiltration Into Sanitary Sewers In Southern Pinellas County, Fl, Megan E. Long Jun 2017

Quantifying And Modeling Surface Inflow And Groundwater Infiltration Into Sanitary Sewers In Southern Pinellas County, Fl, Megan E. Long

USF Tampa Graduate Theses and Dissertations

Following large rain events, excess flow in sanitary sewers from inflow and infiltration (I/I) cause sanitary sewer overflows (SSO), resulting in significant problems for Pinellas County and the Tampa Bay area. Stormwater enters the sanitary sewers as inflow from improper or illegal surface connections, and groundwater enters the system as infiltration through cracks in subsurface infrastructure. This pilot study was designed to develop methods to separate and quantify the components of I/I and to build a predictive model using flowmeter and rainfall data.

To identify surface inflow, daily wastewater production and groundwater infiltration patterns were filtered from the flow data, …


Impact Of Sludge Layer Geometry On The Hydraulic Performance Of A Waste Stabilization Pond, Faissal Romaric Ouedraogo Jun 2016

Impact Of Sludge Layer Geometry On The Hydraulic Performance Of A Waste Stabilization Pond, Faissal Romaric Ouedraogo

USF Tampa Graduate Theses and Dissertations

Improving the hydraulic performance of waste stabilization ponds (WSPs) is an important management strategy to not only ensure protection of public health and the environment, but also to maximize the potential reuse of valuable resources found in the treated effluent. To reuse effluent from WSPs, a better understanding of the factors that impact the hydraulic performance of the system is needed. One major factor determining the hydraulic performance of a WSP is sludge accumulation, which alters the volume of the pond.

In this study, computational fluid dynamics (CFD) analysis was applied to investigate the impact of sludge layer geometry on …


Water Metering In Rural, Piped, Community-Managed Water Systems In The Developing World, Simona Platukyte Mar 2016

Water Metering In Rural, Piped, Community-Managed Water Systems In The Developing World, Simona Platukyte

USF Tampa Graduate Theses and Dissertations

In the early 1990s, the United Nations (UN) recognized water as a finite resource to the entire ecosystem with an economic value that should be developed and managed based on the participatory approach using the Integrated Water Resource Management (IWRM) strategy. Many studies on water management practices have thus emerged in the developing world. Of particular interest to this work is the management of water through metering, price-setting, and rule enforcement in the rural setting in piped, community-owned water systems. There is very little published information regarding metering, enforcement experiments, and experiences in these systems. This is because metering and …


Modeling The Extent Of Virus Removal In Waste Stabilization Ponds To Support Reuse Of Wastewater, Kelly James Vannoy Mar 2016

Modeling The Extent Of Virus Removal In Waste Stabilization Ponds To Support Reuse Of Wastewater, Kelly James Vannoy

USF Tampa Graduate Theses and Dissertations

Waste stabilization ponds (WSPs) are one of the most prevalent types of domestic wastewater treatment technologies employed worldwide, and global stressors such as urbanization, population growth, climate change, and water scarcity have increased the demand for reusing treated wastewater. The safe reuse of treated wastewater in agriculture can ease water scarcity, aid in food production, and reduce environmental degradation from the discharge of wastewater effluent to surface waters. The ability to predict virus concentrations in wastewater effluent is an important criterion for determining whether wastewater is suitable for discharge to the environment or for reuse in agriculture. However, many uncertainties …


Pathogen Removal In Natural Wastewater Treatment And Resource Recovery Systems: Solutions For Small Cities In An Urbanizing World, Matthew Eric Verbyla Nov 2015

Pathogen Removal In Natural Wastewater Treatment And Resource Recovery Systems: Solutions For Small Cities In An Urbanizing World, Matthew Eric Verbyla

USF Tampa Graduate Theses and Dissertations

Sanitation, renewable energy, and food security are among the most pressing global development needs of the century, especially for small cities with rapid population growth. Currently, 53% of the world’s population either lacks access to improved sanitation or discharges fecal waste to the environment without treatment. Furthermore, 80% of food consumed in developing regions is produced by 500 million small farms, and while many of them are still rain-fed, irrigated agriculture is increasing. The post-2015 Sustainable Development Goals, recently adopted by the United Nations, include targets to address the water-energy-food nexus. Wastewater reuse in agriculture can be an important solution …


Evaluation Of First Order Error Induced By Conservative-Tracer Temperature Approximation For Mixing In Karstic Flow, Philippe Machetel, David A. Yuen Oct 2015

Evaluation Of First Order Error Induced By Conservative-Tracer Temperature Approximation For Mixing In Karstic Flow, Philippe Machetel, David A. Yuen

Sinkhole Conference 2015

Fluid dynamics in karst systems is complex due to the heterogeneity of hydraulic networks that combine the Porous Fractured Matrix (PFM) and the interconnected drains (CS). These complex dynamic systems often need to be treated as “black boxes” in which only input and output properties are known. In this work, we propose to assess the first-order error induced by considering the temperature as a conservative tracer for flows mixing in karst (fluvio-karst). The fluvio-karstic system is treated as an open thermodynamic system (OTS), which exchanges water and heat with its surrounding. We propose to use a cylindrical PFM drained by …


Environmental Sustainability Of Wastewater Treatment Plants Integrated With Resource Recovery: The Impact Of Context And Scale, Pablo K. Cornejo Sep 2015

Environmental Sustainability Of Wastewater Treatment Plants Integrated With Resource Recovery: The Impact Of Context And Scale, Pablo K. Cornejo

USF Tampa Graduate Theses and Dissertations

There is an urgent need for wastewater treatment plants (WWTPs) to adapt to a rise in water and energy demands, prolonged periods of drought, climate variability, and resource scarcity. As population increases, minimizing the carbon and energy footprints of wastewater treatment, while properly managing nutrients is crucial to improving the sustainability WWTPs. Integrated resource recovery can mitigate the environmental impact of wastewater treatment systems; however, the mitigation potential depends on various factors such as treatment technology, resource recovery strategy, and system size.

Amidst these challenges, this research seeks to investigate the environmental sustainability of wastewater treatment plants (WWTPs) integrating resource …


New Research In Cave Ledenica In Bukovi Vrh On Velebit Mt In Croatian Dinaric Karst, Mladen Garasic Aug 2014

New Research In Cave Ledenica In Bukovi Vrh On Velebit Mt In Croatian Dinaric Karst, Mladen Garasic

The International Workshop on Ice Caves

No abstract provided.


A Multi-Period Mixed Integer Linear Programming Model For Desalination And Electricity Co-Generation In Kuwait, Nael Abdulhameed Alqattan Jun 2014

A Multi-Period Mixed Integer Linear Programming Model For Desalination And Electricity Co-Generation In Kuwait, Nael Abdulhameed Alqattan

USF Tampa Graduate Theses and Dissertations

Water is the root of life and the engine that drives agriculture, industry, economy and services. The demand for water often necessitates desalination, particularly in arid coastal environments where there are several desalination technologies in use today such as Multi-Effect Distillation (MED) and Reverse Osmosis (RO). The key utility requirement for technologies such as desalination and population in general include energy in one form or another. Therefore, desalination and co-generation are often integrated. Another key utility is electricity which is generated from either renewable or non-renewable sources. The demands for water and electricity change over time and are subject to …


Diffuse Nutrient Pollution From Residential Catchments, Melissa Rachelle Butcher Jun 2014

Diffuse Nutrient Pollution From Residential Catchments, Melissa Rachelle Butcher

USF Tampa Graduate Theses and Dissertations

Nonpoint source nutrient pollution is diffuse pollution lacking discrete origin and conveyance. This thesis synthesizes and critically reviews research on residential nitrogen and phosphorus loss to stormwater runoff and leaching. The evaluation pulls from research covering influential socio-demographic indicators, such as use of lawn maintenance services and homeowner fertilizer practices. The extent to which such social and economic factors may influence the prevalence and fate of diffuse nutrients in stormwater runoff from residential areas has not been adequately established. Understanding the source and influencing factors of diffuse nutrient pollution is important in order to effectively protect surface and groundwater resources. …


An Assessment Of The Emas Pump And Its Potential For Use In Household Water Systems In Uganda, Jacob Daniel Carpenter May 2014

An Assessment Of The Emas Pump And Its Potential For Use In Household Water Systems In Uganda, Jacob Daniel Carpenter

USF Tampa Graduate Theses and Dissertations

Rural improved water supply coverage in Uganda has stagnated around 64% for a number of years and at this point more than 10 million rural people do not have access to an improved drinking water source. It has been recognized that progress toward improved water supply coverage and increased service levels may be gained through Government and nongovernmental organization (NGO) support of private investment in household and shared water supplies, commonly known as Self-supply. Self-supply can be promoted by introducing and building local capacity in appropriate and affordable water supply technologies such as hand-dug wells, manually drilled boreholes, low-cost pumps, …


Drinking Water In The Developing World: Sources Of Fecal Contamination In Pitcher Pump Systems And Measurement Alternatives, Meghan Wahlstrom May 2014

Drinking Water In The Developing World: Sources Of Fecal Contamination In Pitcher Pump Systems And Measurement Alternatives, Meghan Wahlstrom

USF Tampa Graduate Theses and Dissertations

It has been reported that globally we have achieved Millennium Development Goal (MDG) Target 7C, to halve the proportion of the population without access to safe drinking water; however, there is a major flaw with this statement. While Target 7C calls for access to `safe' drinking water, what is actually being measured and reported is access to an `improved' water source. The World Health Organization (WHO) maintains that they must use this proxy measure because the methods for water quality testing are too expensive and logistically complicated, but by doing so, they may be over reporting safe water coverage.

This …


Assessing The Impacts Of Unrestricted Pesticide Use In Small-Scale Agriculture On Water Quality And Associated Human Health And Ecological Implications In An Indigenous Village In Rural Panam[Aacute], Sarah Louise Watson May 2014

Assessing The Impacts Of Unrestricted Pesticide Use In Small-Scale Agriculture On Water Quality And Associated Human Health And Ecological Implications In An Indigenous Village In Rural Panam[Aacute], Sarah Louise Watson

USF Tampa Graduate Theses and Dissertations

In 2014, the global pesticide industry's projected worth is $52 billion and by 2020, the developing world will make up one-third of the world's chemical production and consumption. Pesticides can have unintended negative consequences for human health and the environment, especially in the developing world where regulations are loose or nonexistent. One country with unrestricted use of pesticides is Panam[aacute], especially in Santa Rosa de Cucunatí. In this indigenous village, small-scale farmers and ranchers spray paraquat, glyphosate, picloram, and 2,4-D at higher elevations than the spring water source of a gravity-fed water system, the river, and the village. The objective …


Lead (Pb) Contamination Of Water Drawn From Pitcher Pumps In Eastern Madagascar, David Bradlee Akers Mar 2014

Lead (Pb) Contamination Of Water Drawn From Pitcher Pumps In Eastern Madagascar, David Bradlee Akers

USF Tampa Graduate Theses and Dissertations

Access to safe water supply--a major determinant of public health--is less than 50% in Madagascar, and access to piped, treated water remains out of reach financially for many in the urban and peri-urban areas where available. The Self-supply option of the Pitcher Pump has been meeting the need for household water in coastal areas of Madagascar since the early 1960s and has proven a sustainable option for many. These pumps make use of leaded components in the construction, however, which may pose a health risk for heavy metal intoxication and therefore cause the water to be unsafe for drinking and …