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Articles 181 - 210 of 217
Full-Text Articles in Environmental Engineering
Water Quality Monitoring In A Pilot Marine Integrated Aquaculture System, Alex W. Kruglick
Water Quality Monitoring In A Pilot Marine Integrated Aquaculture System, Alex W. Kruglick
USF Tampa Graduate Theses and Dissertations
Land based aquaculture systems are growing in popularity, and there is a drive to improve the efficiency of their energy and water systems for both economic and environmental benefit. Recirculating Aquaculture Systems (RAS) generally refer to systems that recycle their wastewater streams to be more or less a zero discharge facility. A more sustainable approach is emerging in the form of Integrated Aquaculture Systems (IAS) where maximum utility is realized from the various components so that fresh water use is reduced, water quality is improved, energy use is reduced, and new markets are created or fulfilled. Under a grant from …
Field And Laboratory Comparison Of The Hydraulic Performance Of Two Ceramic Pot Water Filters, Duncan Peabody
Field And Laboratory Comparison Of The Hydraulic Performance Of Two Ceramic Pot Water Filters, Duncan Peabody
USF Tampa Graduate Theses and Dissertations
Currently 884 million people worldwide are living without access to an improved source of drinking water (WHO/UNICEF, 2011). Piped-water on premises is the ultimate goal of World Health Organization (WHO) due to the ability to treat all of the water and distribute it safely in pressurized pipes. However, Household Water Treatment and Safe Storage (HWTS) is an option for improving the quality of drinking water where that infrastructure is not yet developed, especially where there is a risk of recontamination between point of collection and point of use (Clasen, 2006).
This study analyzed one such HWTS, the ceramic pot water …
Analysis And Remediation Of Chlorinated Hydrocarbons In Environmental Media, Jonathan Ticknor
Analysis And Remediation Of Chlorinated Hydrocarbons In Environmental Media, Jonathan Ticknor
USF Tampa Graduate Theses and Dissertations
The two objectives of this work were to develop a simplified method for the analysis of chlorinated organics in water samples and to improve an existing soil remediation technology. The contaminants considered for these studies were chlorinated hydrocarbons because of their relative frequency of appearance at contaminated sites. The first half of this study involved the analysis of chlorinated ethenes by gas chromatography with flame ionization detection (GC-FID). I tested the hypothesis that the FID response factor is the same for all chlorinated ethene compounds. The rationale for this investigation is that if the hypothesis is correct, a single calibration …
Optimization Of An Advanced Water Treatment Plant: Bromate Control And Biofiltration Improvement, Dustin William Bales
Optimization Of An Advanced Water Treatment Plant: Bromate Control And Biofiltration Improvement, Dustin William Bales
USF Tampa Graduate Theses and Dissertations
The David L. Tippin Water Treatment Facility (DLTWTF) serving the city of Tampa, Florida is an advanced drinking water treatment facility consisting of coagulation/flocculation, ozonation, granular activated carbon biofiltration, and disinfection by chloramine. New regulations and the recent economic crisis pushed the facility to investigate methods to decrease costs and meet regulatory requirements easier.
The two major issues identified as priorities for investigation were the optimization of the biofiltration system and the use of a novel process to reduce the formation of bromate during ozonation.
Optimization of the biofiltration system is needed to remove more of the assorted particles that …
Aggregation Of Sediment And Bacteria With Mucilage From The Opuntia Ficus-Indica Cactus, Audrey Lynn Buttice
Aggregation Of Sediment And Bacteria With Mucilage From The Opuntia Ficus-Indica Cactus, Audrey Lynn Buttice
USF Tampa Graduate Theses and Dissertations
Flocculants are commonly used in industrial settings where solid-liquid separations are desired including industrial and municipal wastewater management and potable water production facilities. Conventional flocculants include inorganic metal salts and synthetic organic polymers. The cost, availability, and harmful effects of the non-biodegradable nature of these flocculants have led to the widespread study of natural flocculants. Current natural flocculants being studied include polysaccharides cultivated from microbial extracellular matrix products and plant based materials. In this study, the mucilage of Opuntia ficus-indica cactus was evaluated as a natural flocculant for sediments and bacteria. The O. ficus-indica cactus is also known as the …
Precipitation Of Phosphate Minerals From Effluent Of Anaerobically Digested Swine Manure, Alex Y. Lin
Precipitation Of Phosphate Minerals From Effluent Of Anaerobically Digested Swine Manure, Alex Y. Lin
USF Tampa Graduate Theses and Dissertations
Swine production represents approximately 40% of the world's meat production, and its wastes contain high concentrations of organic carbon, nitrogen (N), and phosphorus (P). Anaerobic digestion is an increasingly popular technology for treating animal wastes while simultaneously generating energy. Its propagation and ability to solubilize organic N and P make adding a struvite recovery process attractive. Recovering struvite (MgNH4PO4) from anaerobically digested swine waste can address global P shortages, meet P discharge guidelines, and produce slow-release fertilizer, which can be sold for revenue.
Anaerobic digesters were operated with at organic loading rates of 3.4-3.9 g volatile solids per liter per …
Water's Dependence On Energy: Analysis Of Embodied Energy In Water And Wastewater Systems, Weiwei Mo
Water's Dependence On Energy: Analysis Of Embodied Energy In Water And Wastewater Systems, Weiwei Mo
USF Tampa Graduate Theses and Dissertations
Water and wastewater treatment is a critical service provided for protecting human health and the environment. Over the past decade, increasing attention has been placed on energy consumption in water and wastewater systems for the following reasons: (1) Water and energy are two interrelated resources. The nexus between water and energy can intensify the crises of fresh water and fossil fuel shortages; (2) The demand of water/wastewater treatment services is expected to continue to increase with increasing population, economic development and land use change in the foreseeable future; and (3) There is a great potential to mitigate energy use in …
Assessing The Reuse Potential Of Wastewater For Irrigation: The Removal Of Helminth Eggs From A Uasb Reactor And Stabilization Ponds In Bolivia, Matthew Eric Verbyla
Assessing The Reuse Potential Of Wastewater For Irrigation: The Removal Of Helminth Eggs From A Uasb Reactor And Stabilization Ponds In Bolivia, Matthew Eric Verbyla
USF Tampa Graduate Theses and Dissertations
Extreme hunger, malnutrition, and the lack of access to sanitation are among the most pressing development challenges, but the world is not on track to meet the targets that have been established by the Millennium Development Goals. The integration of wastewater treatment and food production systems allows for the recovery of resources from wastewater, and can provide an important solution to meet the sanitation needs of growing urban populations and provide periurban farmers with a consistent supply of water and nutrients. Stabilization ponds have been long considered to be an appropriate technology for wastewater reuse systems in developing countries, but …
Comparative Life Cycle Assessments Of Lignocellulosic And Algae Biomass Conversion To Various Energy Products Through Different Pathways, Maria Juliana Pinilla
Comparative Life Cycle Assessments Of Lignocellulosic And Algae Biomass Conversion To Various Energy Products Through Different Pathways, Maria Juliana Pinilla
USF Tampa Graduate Theses and Dissertations
Bioenergy has the potential to reduce the world's dependence on fossil fuels, and to decrease the CO2 emissions due to fossil combustion. Lignocellulosic and algae biomass have been presented as promising feedstocks for bioenergy production.
In this study, a comparative Life Cycle Assessment (LCA) has been developed to evaluate the environmental impacts associated with different energy products via different routes across the whole life of algal and lignocellulosic bioenergy. Results were compared per energy basis, the production of 1 million BTU of energy products.
For the development of the comparative algae biomass conversion LCA, algal biomass was converted to liquid …
Effects Of Solids Loadings And Particle Size Distribution On Siphon Ceramic Candle Filters, Danielle Renzi
Effects Of Solids Loadings And Particle Size Distribution On Siphon Ceramic Candle Filters, Danielle Renzi
USF Tampa Graduate Theses and Dissertations
In the rural areas of Madagascar only 29% of the population has access to clean water and 10% has access to improved sanitation. It has been estimated that environmental risk factors, such as inadequate access to clean drinking water and proper sanitation, are responsible for 94% of the diarrheal disease burden. This study was focused on testing a point-of-use technology called the Tulip filter, which is a siphon ceramic candle filter impregnated with silver. The purpose is to assess its feasibility for implementation in rural regions of Madagascar through a laboratory study performed at the University of South Florida.
The …
Pilot Assessment Of Novel Membrane Bioreactor Processes - Improvements In Biological Nutrient Removal And Membrane Operation, Shaleena Smith
Pilot Assessment Of Novel Membrane Bioreactor Processes - Improvements In Biological Nutrient Removal And Membrane Operation, Shaleena Smith
USF Tampa Graduate Theses and Dissertations
With increasing water reuse applications and upcoming stringent regulations for treated wastewater effluent discharge, wastewater plants need to consider alternative technologies beyond conventional treatment processes. The new regulations, Numeric Nutrient Criteria (NNC), may regulate discharge nitrogen and phosphorus concentrations to as low as 0.5 mg/L as N and 10 μg/L as P respectively. To meet these target requirements, system retrofitting to incorporate chemical or advanced nutrient removal systems possibly with membrane technology will most likely be required. Although microfiltration/ultrafiltration membranes coupled with biological processes, otherwise known as membrane bioreactors (MBR), remove contaminants and suspended solids, nutrient removal is minimal to …
Design Of Small Scale Anaerobic Digesters For Application In Rural Developing Countries, Laurel Erika Rowse
Design Of Small Scale Anaerobic Digesters For Application In Rural Developing Countries, Laurel Erika Rowse
USF Tampa Graduate Theses and Dissertations
The high incidence of upper respiratory diseases, contamination of waterways due to pathogens and nutrients from human and animal wastes, unsustainable deforestation, gender disparities in burden of disease due to unequal exposure to indoor air pollutants, and carbon black emissions from the burning of solid fuels are interrelated problems in many developing countries. Small scale anaerobic digestion provides a means of alleviating these problems by treating livestock waste onsite to produce biogas (methane and carbon dioxide) in rural areas in developing countries. Fuel can then be used for cooking, lighting, and heating. Methane fuel is an alternative to traditional three-stone …
In Situ Biofiltration Of Dissolved Organic Carbon In Reverse Osmosis Membrane Filtration, Russell Rosario Ferlita
In Situ Biofiltration Of Dissolved Organic Carbon In Reverse Osmosis Membrane Filtration, Russell Rosario Ferlita
USF Tampa Graduate Theses and Dissertations
Biofouling, or the formation of biofilm on membrane surfaces, can decrease the performance (decreased flux and/or increased operating pressure) of a reverse osmosis (RO) membrane system in a water treatment plant. However, biofilms have been used in water treatment systems to remove organic carbon from water via biofilters and successfully reduce biofilm growth downstream. This research investigates the possibility that the heterotrophic biofilm present on membrane surfaces removes nutrients from the treatment water, thereby making it nutrient deprived as it travels along the treatment train. This may potentially be exploited as an in situ biofilter to actively remove dissolved organic …
Cactus Mucilage-Assisted Heavy Metal Separation: Design And Implementation, Dawn Iona Fox
Cactus Mucilage-Assisted Heavy Metal Separation: Design And Implementation, Dawn Iona Fox
USF Tampa Graduate Theses and Dissertations
Natural contamination of groundwater by arsenic (As) has become a critical public health threat in many parts of the world. The well-known regions associated with As contamination of groundwater are Bangladesh and West Bengal, India where approximately 100 million people are exposed to high levels of arsenic by drinking arsenic-contaminated groundwater and about 35 million are already affected. Long-term drinking of arsenic-contaminated water leads to arsenicosis, which is characterized by cancers of the skin, organ disease and certain other types of cancer. Affected developing communities are at higher risk because they may not have access to conventional water treatment facilities. …
Feasibility Of Wastewater Reuse For Fish Production In Small Communities In A Developing World Setting, Joshua James Girard
Feasibility Of Wastewater Reuse For Fish Production In Small Communities In A Developing World Setting, Joshua James Girard
USF Tampa Graduate Theses and Dissertations
Eradicating poverty, malnutrition, and the burden of disease have been included as three of the major issues facing the world. The United Nation member countries, having set forth the Millennium Development Goals, have committed themselves to solving these problems. Two major factors which affect solutions to these problems are increasing water stress and implementing improved sanitation. Integration of tilapia aquaculture and reuse of wastewater has been suggested as a solution which addresses both of these factors. The objective of this study is to examine the feasibility, and explore the benefits and drawbacks, to implementing small community wastewater fed (WWF) aquaculture …
Embodied Energy Assessment Of Rainwater Harvesting Systems In Primary School Settings On La Peninsula Valiente, Comarca Ngobe Bugle, Republic Of Panama, Kaitlin Elinor Green
Embodied Energy Assessment Of Rainwater Harvesting Systems In Primary School Settings On La Peninsula Valiente, Comarca Ngobe Bugle, Republic Of Panama, Kaitlin Elinor Green
USF Tampa Graduate Theses and Dissertations
The United Nations Millennium Development goals aim to make improvements in access to potable water. In the Bocas del Toro region of Panama, rainwater harvesting systems are making that goal more attainable. Rainwater harvesting, especially in rural, difficult access areas, may be a viable water source improvement that will allow a greater population to access improved water. This study uses the Carnegie Mellon University Economic Input-output Life Cycle Assessment tool to assess the embodied energy of plastic and ferrocement rainwater harvesting systems in rural Panama. Rainwater harvesting systems are assessed as source improvement technologies that increase access to potable water. …
Biodegradation Of Bisphenol-A And 17b-Estradiol In Soil Mesocosms Under Alternating Aerobic/Anoxic/Anaerobic Conditions, Won-Seok Kim
Biodegradation Of Bisphenol-A And 17b-Estradiol In Soil Mesocosms Under Alternating Aerobic/Anoxic/Anaerobic Conditions, Won-Seok Kim
USF Tampa Graduate Theses and Dissertations
Soil-aquifer treatment (SAT) has been proposed as a method for reusing treated municipal wastewater. SAT is characterized by alternating cycles of aerobic and anaerobic conditions in the subsurface, in response to alternating cycles of flooding and drainage of a surface impoundment. It is not yet known how these alternating redox conditions affect the removal of potentially harmful endocrine-disrupting compounds (EDCs) from treated effluent.
The overall objective of my doctoral research is to determine the fate of EDCs in alternating aerobic/anoxic/anaerobic conditions under simulated SAT conditions. To assess the fate of EDCs in simulated SAT conditions, I first had to develop …
A Swmm-5 Model Of A Denitrifying Bioretention System To Estimate Nitrogen Removal From Stormwater Runoff, Michelle D. Masi
A Swmm-5 Model Of A Denitrifying Bioretention System To Estimate Nitrogen Removal From Stormwater Runoff, Michelle D. Masi
USF Tampa Graduate Theses and Dissertations
This research estimates nitrogen removal from stormwater runoff using a denitrifying bioretention system using the USEPA Storm Water Management Model Version 5 (SWMM-5). SWMM-5 has been used to help planners make better decisions since its development in 1971. A conventional bioretention system is a type of Low Impact Development (LID) technology, which designed without a media layer specifically for achieving nitrogen removal. More recently studies have showed that high TN removal efficiencies are possible when incorporating a denitrification media layer. These systems are known as denitrifying bioretention systems, or alternative bioretention systems. LID projects are currently being designed and developed …
Investigation Of The Optimal Dissolved Co2 Concentration And Ph Combination For The Growth Of Nitrifying Bacteria, Raymond Anthony Morris
Investigation Of The Optimal Dissolved Co2 Concentration And Ph Combination For The Growth Of Nitrifying Bacteria, Raymond Anthony Morris
USF Tampa Graduate Theses and Dissertations
Ammonium (NH4+) is a biological nutrient that is transformed in a wastewater treatment plant (WWTP) in a process called activated sludge. This is accomplished in an aerobic environment using microorganisms and inorganic carbon that convert the ammonium to nitrate (NO3-). This process is termed nitrification. Removal of ammonium is necessary due to its oxygen demand and toxicity to the environment.
Nitrification is considered a slow process due to the slow growth rate of the nitrifying bacteria. Ammonia oxidizing bacteria (AOB) first covert the ammonium (NH4+) to nitrite (NO2-) …
Effectiveness Of In-Line Chlorination Of Gravity Flow Water Supply In Two Rural Communities In Panama, Kevin Orner
Effectiveness Of In-Line Chlorination Of Gravity Flow Water Supply In Two Rural Communities In Panama, Kevin Orner
USF Tampa Graduate Theses and Dissertations
It is well established that water quality is directly linked to health. In-line chlorination is one technology that can be used in the developing world to potentially inactivate pathogens and improve water quality. The purpose of this study was to determine the effectiveness of the Panamanian Ministry of Health's in-line PVC chlorinator under three different operating conditions in a rural water supply system. Free and total chlorine were measured entering the storage tank, leaving the storage tank, and at three households along the transmission line of the water system in the two rural indigenous communities of Calabazal and Quebrada Mina …
Catalytic Hydrodehalogenation And Hydrogenation Of Halogenated Aromatic Organic Contaminants For Application To Soil Remediation, Claire J. Osborn
Catalytic Hydrodehalogenation And Hydrogenation Of Halogenated Aromatic Organic Contaminants For Application To Soil Remediation, Claire J. Osborn
USF Tampa Graduate Theses and Dissertations
The objective of this research was to aid in the development of a new method for removing and destroying soil contaminants. In particular, 1,2,4,5-tetrachlorobenzene (TeCB) was selected for this research. Hydrodehalogenation (HDH) was paired with hydrogenation for remedially destroying TeCB without generating a secondary waste stream in a single batch reactor. Palladium- and rhodium-catalyzed HDH and hydrogenation were applied in a batch reactor at room temperature and moderate hydrogen pressure. Cyclohexane was formed as an end product with benzene as an intermediate reactant.
An analytical method was developed to measure TeCB, benzene, and cyclohexane in a solution of water and …
Environmental Health In The Latin American And Caribbean Region: Use Of Water Storage Containers, Water Quality, And Community Perception, Erlande Omisca
Environmental Health In The Latin American And Caribbean Region: Use Of Water Storage Containers, Water Quality, And Community Perception, Erlande Omisca
USF Tampa Graduate Theses and Dissertations
Water quality and availability are important issues in many developing countries where portions of populations still lack access to potable water. Throughout the English-speaking Caribbean and parts of Latin America, households and businesses invest in water supply systems even when they are connected to and pay for water services from a private or state owned provider. Inconsistent supplies of water from the water companies have led many people to invest in storage tanks which, if operated correctly, can provide water throughout the day even when the supply from the main is low or zero. While these individual systems help to …
An Examination Of The Impacts Of Urbanization On Green Space Access And Water Resources: A Developed And Developing World Perspective, Heather E. Wright Wendel
An Examination Of The Impacts Of Urbanization On Green Space Access And Water Resources: A Developed And Developing World Perspective, Heather E. Wright Wendel
USF Tampa Graduate Theses and Dissertations
This dissertation addresses the impact of urbanization and land use change on the availability and accessibility of two urban amenities that are often inequitably distributed: green space and water features. Diverse methodologies were utilized in order to gain a better understanding of the role of these amenities in improving urban quality of life and integrated water management. Using an interdisciplinary approach, this research provides a unique perspective within both a developed and developing world context by evaluating aspects of urbanization to emphasize more sustainable and integrated approaches to development.
A preliminary analysis highlights potential drivers of green space revitalization in …
Mechanistic Modeling Of Photocatalytic Water Disinfection, Omatoyo Kofi Dalrymple
Mechanistic Modeling Of Photocatalytic Water Disinfection, Omatoyo Kofi Dalrymple
USF Tampa Graduate Theses and Dissertations
The main goal of this research was to develop a mechanism-based model for photocatalytic disinfection of bacteria in water using suspended catalyst pthesiss in batch reactors. The photocatalytic disinfection process occurs as a semiconductor photocatalyst, most commonly titanium dioxide (TiO2), is irradiated with light of wavelength less than 380 nm to produce hydroxyl radicals and other highly reactive oxidants which can inactivate microorganisms. Photocatalytic disinfection involves a complex interaction of many fundamental mechanisms such as light absorption and scattering by semiconductor pthesiss, electrochemical surface reactions, and heterogeneous colloidal stability. Current models, based largely on chemical reacting systems, do …
Anaerobic Membrane Bioreactor (Anmbr) For Treatment Of Landfill Leachate And Removal Of Micropollutants, Anh Tien Do
Anaerobic Membrane Bioreactor (Anmbr) For Treatment Of Landfill Leachate And Removal Of Micropollutants, Anh Tien Do
USF Tampa Graduate Theses and Dissertations
To date, most studies on the fate and removal of endocrine disrupting compounds (EDCs) and pharmaceutical and personal care products (PPCPs) in wastewater focus on their fate in municipal wastewater treatment plants, and mostly under aerobic condition. There are limited studies related to anaerobic condition and (to our knowledge) no study on the removal of EDCs in landfill leachate by AnMBR. Moreover, for most studies under anaerobic condition, the removal of EDCs was only reported in the liquid phase; solid phase extraction was not reported, thereby preventing mass balance in the studies.
This research was conducted to investigate the potential …
Sequential Anaerobic And Algal Membrane Bioreactor (A2mbr) System For Sustainable Sanitation And Resource Recovery From Domestic Wastewater, Ana Lucia Prieto
Sequential Anaerobic And Algal Membrane Bioreactor (A2mbr) System For Sustainable Sanitation And Resource Recovery From Domestic Wastewater, Ana Lucia Prieto
USF Tampa Graduate Theses and Dissertations
An innovative wastewater treatment technology was developed to recover renewable resources, such as water, energy and nutrients, from sewage. First, a novel synthetic sewage was evaluated for its suitability to serve as an alternative substrate for lab-scale wastewater treatment (WWT) research. Based on granular dried cat food, Complex Organic Particulate Artificial Sewage (COPAS) is a commercially-available, flexible, and easy to preserve feed. Characteristics of COPAS, namely chemical composition, disintegration/dissolution kinetics, and anaerobic biodegradability, were determined. Anaerobic bioassays indicate that COPAS is highly biodegradable at the concentration used to simulate household sewage (1000 mg/L), with more than 72% of the theoretical …
Computational Discovery Of Phenotype Related Biochemical Processes For Engineering, Andrea M. Rocha
Computational Discovery Of Phenotype Related Biochemical Processes For Engineering, Andrea M. Rocha
USF Tampa Graduate Theses and Dissertations
Application of bioengineering technologies for enhanced biological hydrogen production is a promising approach that may play a vital role in sustainable energy. Due to the ability of several naturally occurring microorganisms to generate hydrogen through varying metabolic processes, biological hydrogen has become an attractive alternative energy and fuel source.
One area of particular interest is the production of biological hydrogen in organically-rich engineered systems, such as those associated with waste treatment. Despite the potential for high energy yields, hydrogen yields generated by bacteria in waste systems are often limited due to a focus on microbial utilization of organic material towards …
Comparison Of Safety Performance By Design Types At Freeway Diverge Areas And Exit Ramp Sections, Hongyun Chen
Comparison Of Safety Performance By Design Types At Freeway Diverge Areas And Exit Ramp Sections, Hongyun Chen
USF Tampa Graduate Theses and Dissertations
The primary objective of the study is to evaluate the safety performance of different freeway exit types used in current practical designs. More specific, the research objectives include the following two parts: 1) to compare the safety performance of different design types at freeway diverge areas and exit ramp sections; and 2) to identify the impact factors contributing to the crashes happening at these two specific segments.
The study area includes four subjects, the freeway widely-spaced diverge areas; the freeway closely-spaced diverge areas; the left-side off-ramps and the exit ramp sections. For the freeway diverge areas, design types were defined …
The Green And Ampt Infiltration Model Accounting For Air Compression And Air Counterflow In The Shallow Water Table Environment: Laboratory Experiments, Yuliya Lukyanets
The Green And Ampt Infiltration Model Accounting For Air Compression And Air Counterflow In The Shallow Water Table Environment: Laboratory Experiments, Yuliya Lukyanets
USF Tampa Graduate Theses and Dissertations
Water infiltration into the unsaturated zone especially in a shallow water table environment is affected by air compression ahead of the wetting front and air counterflow. Neglecting air compression in infiltration modeling can overestimate infiltration and infiltration rates, whereas not accounting for air counterflow can underestimate infiltration and infiltration rates due to unrealistic buildup of air pressure resistance ahead of the wetting front. A method, derived on the basis of the Green and Ampt (1911) infiltration model, is introduced to simulate air compression and air counterflow during infiltration into a shallow water table. The method retains the simplicity of the …
An Analysis Of The Travel Patterns And Preferences Of The Elderly, Sujan Sikder
An Analysis Of The Travel Patterns And Preferences Of The Elderly, Sujan Sikder
USF Tampa Graduate Theses and Dissertations
The number of elderly is increasing; to meet their transportation needs, it is important to clearly understand their travel patterns and preferences. Since travel patterns and preferences depend on socio-demographic and other factors, it is essential to identify these factors first to understand the travel behavior of the elderly. The main purpose of this thesis is to analyze the travel patterns and preferences of the elderly age 65 and above using 2009 National Household Travel Survey (NHTS) data. This thesis presents a detailed descriptive analysis of 2009 NHTS data to understand the travel patterns of the elderly. Along with a …