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Modeling Power Generation Losses Due To Environmental And Fish Passage Attraction Flows At A Run-Of-River Hydroelectric Operation In The Northeast, Elizabeth A. Lotter
Modeling Power Generation Losses Due To Environmental And Fish Passage Attraction Flows At A Run-Of-River Hydroelectric Operation In The Northeast, Elizabeth A. Lotter
Environmental & Water Resources Engineering Masters Projects
Environmental mitigation represents an important, recurring cost to the hydropower industry, the largest renewable power source in the United States. Environmental flows are one such expense whereby hydro operations maintain a minimum flow in the river to mitigate impacts on aquatic and riparian ecosystems. Any hydroelectric facility may have a habitat maintenance flow requirement, but facilities with assisted aquatic organism passage structures, or fishways, may be subject to additional flow requirements associated with specific species migrations. This study assesses the economic impact of meeting environmental flow requirements in terms of losses to power generation at a representative hydroelectric facility and …
Natural Organic Matter (Nom) Precursors Characterization In Source Water By Surrogate Measurements And Disinfection Byproducts (Dbps) Analysis, Mohammad (Kiron) Shakhawat
Natural Organic Matter (Nom) Precursors Characterization In Source Water By Surrogate Measurements And Disinfection Byproducts (Dbps) Analysis, Mohammad (Kiron) Shakhawat
Environmental & Water Resources Engineering Masters Projects
Natural organic matter (NOM) is the main source of organic precursors for organic disinfection byproducts (DBPs) in treated drinking water.Aquatic NOM is a heterogeneous mixture consisting of both hydrophobic and hydrophilic compounds. The hydrophobic fraction includes humic substances, primarily humic acids and fulvic acids. In most waters, fulvic acid is considered to be the major portion of the hydrophobic fraction. Humic substances are formed by decaying vegetative matter, such as lignin. Lignin is found in plants and is quite resistant to biodegradation, yet it is reactive with oxidants, such as chlorine. Thus, water continuing higher amounts of aromatic hydrophobic humic …
Large-Scale Electrochemical Degradation Of Poly-And Perfluoroalkyl Substances (Pfas) By Magnéli Ti4o7 Electrodes, Laura Siddon
Large-Scale Electrochemical Degradation Of Poly-And Perfluoroalkyl Substances (Pfas) By Magnéli Ti4o7 Electrodes, Laura Siddon
Environmental & Water Resources Engineering Masters Projects
Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a group of synthetic chemicals that are extremely persistent in the environment. They classified as emerging contaminants and have been linked to impacts on the developmental, liver, immune, and thyroid systems, and are possible carcinogens. PFAS’ resistance to biodegradation and conventional oxidation processes make them one of the hardest chemicals to remove from water. With the discovery of PFAS in public water supplies, existing technologies are not capable of removing these recalcitrant contaminants to levels expected for the health of the public. Even in cases when conventional technologies can remove PFAS compounds, removal is …
Rain Rain Flush Away: Evaluating Rainwater Catchment First Flush Volumes, Bridgette Charlebois
Rain Rain Flush Away: Evaluating Rainwater Catchment First Flush Volumes, Bridgette Charlebois
Environmental & Water Resources Engineering Masters Projects
Rainwater harvesting systems often include quality control systems such as a diverted first flush volume to improve the collected water quality. The first flush volume has traditionally been defined as a set volume of rain based on the first 1-2 millimeters of rain that falls on a roof. Diverting a volume of water can be seen as a waste when rainwater is a main source of potable water, sometimes leading to lack of implementation, and thus contaminating the final collected water. Understanding the variability of first flush volume required due to environmental parameters can be used to develop an optimized …
Effect Of Intermittent Water Supply On Water Quality In A Model Pipeloop, Mariam Alkattan
Effect Of Intermittent Water Supply On Water Quality In A Model Pipeloop, Mariam Alkattan
Environmental & Water Resources Engineering Masters Projects
Intermittent water supply (IWS) is defined as a piped drinking water distribution system that operates for less than 24 hours per day. Water quality is found to be negatively impacted in IWS, which creates a human health risk. There are still may gaps in our understanding of pathways of contamination in IWS, which has been a limitation in creating appropriate solutions to maintain water quality in IWS systems. To characterize these pathways, we ran a study to investigate the impact of intermittency on water quality, biofilms, and water pressure in IWS, which consisted of constructing two identical model drinking water …
Using Remote Sensing And Environmental Precursors To Detect And Predict Cyanobacteria Harmful Algal Blooms In Northeastern Us Waterbodies, Amanda Craver
Environmental & Water Resources Engineering Masters Projects
Cyanobacteria harmful algal blooms (cyanoHABs) are a global problem with human health, environmental, and economic concerns. The severity and frequency of toxic cyanoHABs are expected to increase with climate change. Remote sensing has proven to be a useful tool in monitoring cyanoHABs. This study uses remote sensing observations from Sentinel-3Ocean Land Color Imager (OLCI)combined with the Spectral Shape Algorithm (SSA) to detect the presence of cyanobacteria in numerous waterbodies throughout the Northeast United States over 2016to 2020. The ACOLITE processor was used for the atmospheric correction of the Sentinel-3 OLCI data, as it has been shown to provide more accurate …
Drought Characteristics In The Lower Mekong River Basin And Relationship To Land Cover Change, Heejun Park
Drought Characteristics In The Lower Mekong River Basin And Relationship To Land Cover Change, Heejun Park
Environmental & Water Resources Engineering Masters Projects
Drought can have devastating effects on regional water resources and agriculture, with an estimated US$96 billions of damages globally between 2005 and 2015. In the Lower Mekong Basin, the impacts of drought have been a major concern for local stakeholders as the region is the largest rice-producing area in the world. Few studies of long-term drought in the region have directly assessed the effects of land cover changes on both agricultural and hydrological drought. We used a suite of remote sensing data to assess drought characteristics in five countries of this region (Vietnam, Cambodia, Thailand, Laos, Myanmar) where traditional in-situ …
Control Effect Of Peracetic Acid On Chlorinated Dbp Formation And The Application Of Paa Pre-Oxidation In Drinking Water Treatment, Yue Sun
Environmental & Water Resources Engineering Masters Projects
Chlorine has been applied as the main disinfectant in US drinking water treatment for a century. Chlorination is low cost and effective, yet there are problems with this technology, including disagreeable taste of treated drinking water and formation of toxic and potentially carcinogenic disinfection byproducts (DBPs). Alternative disinfection methods including ozone, ferrate and UV light have been studied. They are not widely applied in drinking water treatment because of problems such as the costly generation process or no residual in the system.
Peracetic acid, an easy-to-use and economic friendly oxidant, has been applied as an alternative disinfectant to chlorine in …
A Framework For Meeting Economic And Ecological Objectives In Hydropower Operations, Sarah L. Pfeifle
A Framework For Meeting Economic And Ecological Objectives In Hydropower Operations, Sarah L. Pfeifle
Environmental & Water Resources Engineering Masters Projects
Hydropower is a low carbon energy source that provides reliable power, but imposes large, artificial sub-daily changes in flow that negatively impact ecological systems. Hydropower management faces the challenge of meeting economic and ecological objectives, neither of which can be fully optimized because of their Pareto nature. This study introduces an operational framework, called seasonal flexibility, as tool that aims to meet both sets of objectives. Economic objectives are met by allowing releases to deviate from inflows to generate power when it is most valuable. Ecological objectives are met by dynamically managing environmental flows to mitigate downstream impacts. Flexibility is …
Analysis Of Road Salt Loading And Transport In The Wachusett Reservoir Watershed, Joshua Soper
Analysis Of Road Salt Loading And Transport In The Wachusett Reservoir Watershed, Joshua Soper
Environmental & Water Resources Engineering Masters Projects
Chloride exports from the widespread application of road salt serve as a primary contribution to water body salinity in cold climate regions. The detrimental effects of road salt pollution on water quality include an apparent relationship between chloride and water corrosivity. This study utilizes regression based chloride load estimation to support mass balances and analyze transport flow-paths to the Wachusett Reservoir from its predominantly rural watershed. Results from hydrograph and load separation techniques show that average loading and discharge from baseflow contributed approximately 74% and 65% of the total loading and discharge, respectively. The baseflow dominated tributary chloride loading is …
Optimizing Household Water Decisions For Managing Intermittent Water Supply In Mexico City, Savannah Wunderlich
Optimizing Household Water Decisions For Managing Intermittent Water Supply In Mexico City, Savannah Wunderlich
Environmental & Water Resources Engineering Masters Projects
Nearly 1 billion people around the world experience intermittent water supply (IWS), including about 70% of residents in the Mexico City area. Households with IWS often rely on multiple sources of water to meet their needs, including municipal piped water, trucked water, and rainwater. When calculating water costs and reliability of supply, models of these systems must account for household decision-making regarding the volume of water to use from each different source each day. Modeling these household decisions (or “control policies”) is challenging, especially when households use rainwater as a water source, due to the complexity of the input variables …
3d Printed Architected Materials For Improving Biofilm Carriers For Wastewater Treatment Applications, Bryan Ovelheiro
3d Printed Architected Materials For Improving Biofilm Carriers For Wastewater Treatment Applications, Bryan Ovelheiro
Environmental & Water Resources Engineering Masters Projects
Wastewater infrastructure in the United States has been in dire need of improvement for quite a while. It was estimated that wastewater treatment systems would need about $57.2 billion to maintain acceptable levels of treatment in the coming years (Christen, 2003). This is just for maintaining the treatment systems in place, without any room for improvement, and it only accounts for about 31.6% of the total waster infrastructure need in this area (Christen, 2003). In fact, without sufficient upgrades, water quality gains achieved through the passing of the Clean Water and Safe Drinking Water acts could be lost (Christen, 2003). …
Complexities Of Attraction Water Systems: A Review & An Experiment Showcasing Their Effects, Marcia Rojas
Complexities Of Attraction Water Systems: A Review & An Experiment Showcasing Their Effects, Marcia Rojas
Environmental & Water Resources Engineering Masters Projects
The presence of dams has direct negative effects on populations of migrating fish and their riverine habitat as well as impacts on the ecosystem services they provide. Fishways, provide upstream and downstream passage that is safe and timely, comprising specifically of “physical structures, facilities, or devices necessary to maintain all life stages of such fish, and project operations and measures related to such structures, facilities, or devices which are necessary to ensure the effectiveness of such structures, facilities or devices for such fish” (National Energy Policy Act 1992). Fishways, sloped channels or elevators that connect the tailrace to the head …
The Success, Morphology, And Performance Of Oxygenic Photogranules Under Light-Induced Stress Conditions, Samuel Downes
The Success, Morphology, And Performance Of Oxygenic Photogranules Under Light-Induced Stress Conditions, Samuel Downes
Environmental & Water Resources Engineering Masters Projects
No abstract provided.
Evaluation Of Two Real Time Methods For Assessing Thm Precursor Concentrations, Griffin Moriarty
Evaluation Of Two Real Time Methods For Assessing Thm Precursor Concentrations, Griffin Moriarty
Environmental & Water Resources Engineering Masters Projects
Conventional drinking water treatment generally requires maintenance of a disinfectant residual, most commonly free or combined chlorine. Since the discovery of disinfection byproducts (DBPs), utilities have relied on a broad range of water quality parameters to help them achieve compliance with DBP regulations. Most notably, dissolved organic carbon (DOC) and ultraviolet absorbance at 254 nm (UV254) have been used to assess DBP precursor levels in near-real time. These are often compared to actual system DBP concentrations or to results from laboratory DBP precursor tests resulting in a site-specific precursor-DBP model. The DOC or UV254 models are often inaccurate, requiring re-calibration, …
An Assessment Of Lead And Copper In School Drinking Water, Kaavya Raghavan Ram
An Assessment Of Lead And Copper In School Drinking Water, Kaavya Raghavan Ram
Environmental & Water Resources Engineering Masters Projects
Metal contamination in drinking water, especially heavy metals such as lead, and corrosion issues, pose a threat to human health and have received increasing attention in recent years. This study reports on the results of ‘The Massachusetts Assistance Program for Lead in School Drinking Water’ and provides a better understanding of the dynamics of sampling protocols, premise plumbing and their influence on lead and copper concentrations. ‘The Massachusetts Assistance Program for Lead in School Drinking Water’ that was announced in April 2016, implemented tap-based water sampling for lead and copper at K-12 public schools and Early Education and Childcare centers …
Developing A Toolkit For Citizen Scientists' Evaluation Of Drinking Water Quality, Leighann D'Andrea
Developing A Toolkit For Citizen Scientists' Evaluation Of Drinking Water Quality, Leighann D'Andrea
Environmental & Water Resources Engineering Masters Projects
This project evaluated tools for citizen science by assessing the potential to monitor drinking water quality at home with commercially sold, or off the shelf, test kits. The first objective was to compare the results of off the shelf test kits with laboratory-obtained values as performed in a controlled environment by trained laboratory personnel. The second objective was to provide potential citizen scientists with a selection of test kits to determine if they could successfully use the kits. These two objectives contributed to the end goal of understanding whether test kits on the market existed that could be used by …
Modeling Nature-Based Solutions For Climate Resilience, Mason Saleeba
Modeling Nature-Based Solutions For Climate Resilience, Mason Saleeba
Environmental & Water Resources Engineering Masters Projects
Riparian wetlands can serve as nature-based infrastructure that slow the rapid movement of water during high flow events. As the recurrence of high flow events increases due to global climate change, an improved understanding of the potential of wetland landscapes to provide flood mitigation is needed. This research addresses both the impacts of climate change and land cover on extreme flow events in the Otter Creek watershed in Vermont. The upstream portion of the basin is modeled with the Soil and Water Assessment Tool (SWAT) to investigate the impacts of climate change on extreme flow events. A Hydrologic Engineering Center's …
Seasonal Impacts Of Climate Change On Future Peak River Discharge In The U.S. Northeast, Christina Wu
Seasonal Impacts Of Climate Change On Future Peak River Discharge In The U.S. Northeast, Christina Wu
Environmental & Water Resources Engineering Masters Projects
This research uses projected changes in future precipitation to calculate the changes in the magnitude, frequency, and timing of streamflow, particularly peak annual flows, in the U.S. Northeast through 20 representative watersheds. Temperature and precipitation data on a 3-hourly time step from five climate projection from the North American Regional Climate Change Assessment Program (NARCCAP) are downscaled and bias- corrected using the Spatial Downscaling and Bias Correction (SDBC) method. These data are used to force a regional hydrological model (WRF-Hydro) to estimate daily future streamflow. The changes in magnitude at various return intervals of peak flow events are determined through …
Formation Of Low-Molecular-Weight Dissolved Organic Nitrogen In Two-Stage And Four-Stage Pre-Denitrification Biological Nutrient Removal Processes, Siwei Chen
Environmental & Water Resources Engineering Masters Projects
To alleviate the eutrophication caused by excessive loading of nutrients, the upgrading of conventional activated sludge (CAS) process to biological nutrients removal (BNR) process has been widely applied in USA. In this study, we found that the dissolved inorganic nitrogen (DIN) release can be effectively controlled by this upgrading, but dissolved organic nitrogen (DON) especially LMW-DON, which now is regarded as another important N source for supporting growth of phytoplankton in coastal water, cannot be removed effectively by BNR systems, especially by four-stage BNR systems. Different pre-denitrification BNR processes have different LMW-DON production rates. A four-stage pre-denitrification BNR releases more …
Application Of Ce-Qual-W2: Wachusett Reservoir Contaminant Spill Modeling, William Yan
Application Of Ce-Qual-W2: Wachusett Reservoir Contaminant Spill Modeling, William Yan
Environmental & Water Resources Engineering Masters Projects
This research was done to investigate the fate and transport of a simulated contaminant spill into Wachusett Reservoir using the CE-QUAL-W2 model. The reservoir is located in central Massachusetts (north east of Worcester) and was first filled in 1908. The Massachusetts Water Resource Authority (MWRA) uses the reservoir as a primary source of drinking water for the metropolitan Boston area. The 65-billion-gallon reservoir is replenished by 9 tributaries and also supplemented by the transfer of water from Quabbin Reservoir (412 billion-gallon capacity) through the Quabbin Aqueduct. This transfer is used to meet system water demands, manage the water surface elevation …
Development Of Application Software For Water System Data Management, Visualization, And Analysis With The Shiny Framework, Nicholas Zinck
Development Of Application Software For Water System Data Management, Visualization, And Analysis With The Shiny Framework, Nicholas Zinck
Environmental & Water Resources Engineering Masters Projects
A comprehensive watershed protection plan includes the collection of water quality, meteorological, and hydrological data. Large amounts of data can be difficult to manage if proper systems are not put in place for data management. Poor data management can be detrimental and may result in data loss, poor quality data, or underutilized data due to the lack of an efficient process of querying, visualizing, and analyzing data. Database software is a great solution to store and organize large datasets, yet database software often lack data visualization and analysis tools. Commonly, databases are paired with an outside application specialized for data …
Determination Of The Rate Constant For Reaction Of Ozone With 1-Hexene In Water, Pranav Mashankar
Determination Of The Rate Constant For Reaction Of Ozone With 1-Hexene In Water, Pranav Mashankar
Environmental & Water Resources Engineering Masters Projects
Low molecular weight aldehydes such as formaldehyde may be formed as disinfection byproducts (DBPs) of ozonation when low molecular weight, aliphatic, alpha olefins are present as contaminants in water. Such alkenes form a small but significant part of crude oil, and would therefore be present in water contaminated with an oil spill. This project studied the kinetics of the reaction between ozone and 1-hexene in water as part of a study to predict the effects of an oil spill on the water quality in the Wachusett reservoir in Massachusetts. The data for the reaction rate constant for the aqueous ozonolysis …
Factors Impacting The Cultivation, Structure, And Oxygen Profiles Of Oxygenic Photogranules For Aeration-Free Wastewater Treatment, Megan Hann
Environmental & Water Resources Engineering Masters Projects
Oxygenic photogranules (OPGs) are novel biogranules which have successfully treated wastewater without external aeration at the bench scale. The formation of OPGs under both static and hydrodynamic conditions is a unique phenomenon which has no known counterpart. This report examines some of the granulation mechanisms and structural and functional differences between statically and hydrodynamically cultivated OPGs. As previously reported, filamentous cyanobacteria are an essential component of both types of OPGs. The addition of Oscillatoria in augmented activated sludge inoculum showed successful static OPG formation in a shorter time (28 vs 35 days) and produced more settled OPGs than native sludge …
Effect Of Substrate Roughness, Slope, And Body Size On Climbing Behavior And Performance Of Juvenile American Eels (Anguilla Rostrata), Zahra Anwar
Environmental & Water Resources Engineering Masters Projects
The effect of ramp slope and substrate grain size on the passage of juvenile American Eel (Anguilla rostrata) over indoor ramps was tested from May – August 2016. Two size classes of fish (300 glass eels 50 – 70 mm and 300 elvers 90-114 mm), five substrates varying in coarseness (Substrate 1: 0.18-0.25 mm grain size, Substrate 2: 0.25-0.60 mm grain size,
Substrate 3; 0.60-1.00 mm grain size, Substrate 4: 1.00 – 2.00 mm grain size, Substrate 5: 2.00-
4.00 mm grain size), and three ramp slopes (25, 35 and 45 degrees) were explored. Individual fish were placed …
Restoring Floodplains In The Connecticut River Basin: A Flood Management Strategy, Abigail Ericson
Restoring Floodplains In The Connecticut River Basin: A Flood Management Strategy, Abigail Ericson
Environmental & Water Resources Engineering Masters Projects
This research investigates how changes to floodplains in the Connecticut River Basin impact flood events. Climate impacted flows and increased development within the floodplain could lead to worsening flood events and less habitat availability for threatened species. Potential future conditions are evaluated through a wide range of scenarios to assess the range of possible impacts using a HEC-RAS 2D model. Three different flood events, 1-yr, 10-yr, and 100-yr, are evaluated for each scenario. Five metrics, Discharge, Depth, Time of Arrival, Flooding Duration, and Number of Buildings Flooded, are tracked for each scenario. These metrics are compared to select the ideal …
Robust Drought Planning In Megacities: A Case Study In São Paulo, Brazil, Grace Cambareri
Robust Drought Planning In Megacities: A Case Study In São Paulo, Brazil, Grace Cambareri
Environmental & Water Resources Engineering Masters Projects
The megacity of São Paulo, Brazil recently faced a severe three-year drought (2013- 2015) that highlighted the challenges of growing water demands, unpredictability of future supply, and proper communication with the public during crisis. Given the poor outcomes of the recent drought, the question remains as to how the drought can be used to inform and improve future drought preparedness. This study develops a seven-step framework using simulation and a computational search to identify promising drought plans based on the historic record. These promising plans are then tested under alternative states of the world to explore their robustness and identify …
Pilot Reactor Operation Of The Oxygenic Photogranule (Opg) Wastewater Treatment Process, Adam Matthew Mcnair
Pilot Reactor Operation Of The Oxygenic Photogranule (Opg) Wastewater Treatment Process, Adam Matthew Mcnair
Environmental & Water Resources Engineering Masters Projects
Treating wastewater is imperative for maintaining public health and sanitation as well as the natural environment. In the United States and developed countries around the globe, the activated sludge (AS) process has been paramount in effectively treating wastewater for over a century. However, high energy consumption due to required mechanical aeration of AS limits its potential as a sustainable process. The oxygenic photogranule (OPG) wastewater treatment process utilizes the photosynthetic ability of OPGs made possible by the symbiosis between heterotrophic AS and filamentous cyanobacteria and algae in dense, spherical biogranules. This research presents pilot operation of the OPG wastewater treatment …
Effects Of Sulfidation On The Deposition And Detachment Of Silver Nanoparticles, Joseph Murphy
Effects Of Sulfidation On The Deposition And Detachment Of Silver Nanoparticles, Joseph Murphy
Environmental & Water Resources Engineering Masters Projects
The transformation of silver nanoparticles (AgNPs) due to environmental factors can play a role in their fate and transport in aquatic systems. Sulfidation has the potential to alter these particles’ physio-chemical properties and their subsequent mobilization in aquatic environments. The water chemistry (e.g. pH, dissolved organic carbon) of these systems can also change the behavior of AgNPs. To better understand the effects of sulfidation on the characteristics and deposition of AgNPs, techniques such as quartz crystal microgravimetry (QCM) and dynamic light scattering (DLS) were used. In this study, AgNPs with two different ligand types, Polyvinylpyrrolidone (PVP)-capped AgNPs (PVP-AgNPs) and Polyethylene …
Evaluation Of Disinfection Byproduct Speciation Models Based On Biodegradation And Chemical Decomposition, Xian Ma
Environmental & Water Resources Engineering Masters Projects
The USEPA has regulated both chlorinated and brominated trihalomethanes (THMs) and haloacetic acids (HAAs) since Stage 2 D/DBP Rule. Among regulated species, all four chlorinated and brominated THMs are regulated as total TTHMs (TTHM). But of the nine HAAs, only the sum of five (HAA5) are regulated, with no detail on individual species. This leaves four unregulated HAAs of which all contain bromine. With more attention on the brominated haloacetic acids due to their higher toxicity, the focus on the formation of those unregulated brominated species is elevated. The objective of this study is to assess national occurrence of all …