<p> The purpose of this thesis is to provide a combined theoretical and experimental approach to solve several enduring questions in wastewater chemistry. Firstly, the sulfate radical has been proposed as an alternative oxidant in advanced oxidation processes (AOPs). Its reactivity with dissolved organic matter (DOM) has not yet been studied and will be quantied in this work using electron pulse radiolysis. Next, it has been shown that DOM present in wastewater can act to impede the remediation of harmful pharmaceutical contaminants in the AOP. Using a new binding model presented here, this association was quantied in terms of equilibrium constants. Lastly, due to the use of bleach to prevent biofouling of the membrane bioreactor in wastewater treatment facilities, chlorine atom chemistry is becoming increasingly important to study regarding AOPs. A numerical system is provided in this thesis to understand the reactivity of chlorine atoms in the presence of wastewater constituents.</p><p>

<p> Between 1990 and 2010 changing perceptions of water-scarcity and evolving adaptation strategies to water stress transformed water management in San Diego, California. This project examines how perceptions of water scarcity affect the programmatic variety, geographic scale, and types of adaptations that are undertaken. It also investigates whether a cultural consensus developed within San Diego County as a whole about what causes particular water problems. Lastly, the research shows how adaptation responses to the collective action problem of water provisioning contributed to resolving the other collective action problems of wastewater production and water conservation. The project presents San Diego as an example of polycentric governance arrangements that were adaptive to the challenges of a changing social-ecological system. </p><p>

abstract: Cities are, at once, a habitat for humans, a center of economic production, a direct consumer of natural resources in the local environment, and an indirect consumer of natural resources at regional, national, and global scales. These processes do not take place in isolation: rather they are nested within complex coupled natural-human (CNH) systems that have nearby and distant teleconnections. Infrastructure systems—roads, electrical grids, pipelines, damns, and aqueducts, to name a few—have been built to convey and store these resources from their point of origin to their point of consumption. Traditional hard infrastructure systems are complemented by soft infrastructure, such as governance, legal, economic, and social systems, which rely upon the conveyance of information and currency rather than a physical commodity, creating teleconnections that link multiple CNH systems. The underlying structure of these systems allows for the creation of novel network methodologies to study the interdependencies, feedbacks, and timescales between direct and indirect resource consumers and producers; to identify potential vulnerabilities within the system; and to model the configuration of ideal system states. Direct and indirect water consumption provides an ideal indicator for such study because water risk is highly location-based in terms of geography, climate, economics, and cultural norms and is manifest at multiple geographic scales. Taken together, the CNH formed by economic trade and indirect water exchange networks create hydro-economic networks. Given the importance of hydro-economic networks for human well-being and economic production, this dissertation answers the overarching research question: What information do we gain from analyzing virtual water trade at the systems level rather than the component city level? Three studies are presented with case studies pertaining to the State of Arizona. The first derives a robust methodology to disaggregate indirect water flows to subcounty geographies. The second creates city-level metrics of hydro-economic vulnerability and functional diversity. The third analyzes the physical, legal, and economic allocation of a shared river basin to identify vulnerable nodes in river basin hydro-economic networks. This dissertation contributes to the literature through the creation of novel metrics to measure hydro-economic network properties and to generate insight into potential US hydro-economic shocks. / Dissertation/Thesis / Doctoral Dissertation Civil and Environmental Engineering 2016

<p> Redevelopment of the Granite Run Mall, a nearly 100% impervious 34 ha site in Media, Pennsylvania, required upgrading the site&rsquo;s 40-year old stormwater control measures (SCMs) to comply with local modern ordinances. With its headwaters adjacent to the site, Chrome Run has received the mall&rsquo;s stormwater runoff for decades with deleterious effects on all levels of stream functions. Thus, the mall&rsquo;s redevelopment was an ideal opportunity to examine the effectiveness of current stormwater practices and validate the approach of focusing SCM implementation in headwaters. Specifically the study aimed to determine if the damage to the receiving waters could be reversed by conducting a 3 year long Before-After-Control-Impact study. To these ends in the summer of 2016, a rigorous monitoring program was established in Chrome Run along with three control streams. Areas of investigation included hydrology, hydraulics, geomorphology, biology, and numerous physicochemical parameters. This thesis details the materials and methods employed in addition to an analysis of the pre-redevelopment data to establish the baseline conditions along Chrome Run and quantify the stream&rsquo;s impairment.</p><p>

<p> The purpose of this study was to develop a better understanding of water-conscious residents&rsquo; thought processes that may lead to behavioral and attitudinal changes when introduced to information that increased their awareness of the amount of water used by the beef and dairy industry in Arizona. A total liberation framework rooted in critical animal studies provided the theoretical foundation for explaining how speciesism and carnism support the power structures of the animal industrial complex and how cognitive dissonance theory may affect future efforts toward engaging more people in the resistance of this oppressive, violent, and unjust system. Research showed that over 40 percent of Arizona&rsquo;s fresh water withdrawals are used to grow crops for animal consumption. This information was presented to a focus group consisting of seven participants interested in water conservation and consumed beef every week. A mixed methods approach to analyzing quantitative and qualitative data explored the complex decision-making process that influences an individual&rsquo;s beliefs and behavioral choices to continue, reduce, or eliminate beef and dairy from their diet. The data resulted in the postulation that introducing water-conscious citizens to the amount of water used by the beef and dairy industry causes cognitive dissonance, encouraging them to reduce their beef and dairy consumption and consider underlying power structures that support animal agribusiness as they reconcile the dissonance between their current behavior to conserve water and their current behavior to consume beef and dairy.</p><p>

<p> During <i>in situ</i> remediation of contaminated groundwater, a treatment chemical is injected into the contaminated groundwater to degrade a contaminant through chemical reaction that occurs in the subsurface. Reactions and subsequent contaminant degradation occur only where the treatment chemical contacts the contaminant long enough to complete degradation reactions. Traditional <i> in situ</i> groundwater remediation relies on background groundwater flow to spread an injected treatment chemical into a plume of contaminated groundwater. </p><p> Engineered Injection and Extraction (EIE), in which time-varying induced flow fields are used to actively spread the treatment chemical into the contaminant plume, has been developed to increase contact between the contaminant and treatment chemical, thereby enhancing contaminant degradation. EIE has been investigated for contaminants degrading through irreversible, bimolecular reaction with a treatment chemical, but has not been investigated for a contaminant governed by complex biogeochemical processes. Uranium fate and transport in subsurface environments is governed by adsorption, oxidation reduction, solution, and solid-phase interactions with naturally occurring solution species, microbial communities, minerals and aquifer media. Uranium primarily occurs in aqueous, mobile U(VI) complexes in the environment but can be reduced to sparingly soluble, immobile U(IV) solid-phase complexes by native dissimilatory metal reducing bacteria. </p><p> This work investigates the ability of EIE to promote subsurface delivery of an acetate-amended treatment solution throughout a plume of uranium-contaminated groundwater to promote <i>in situ</i> growth of native microbial communities to immobilize uranium. Simulations in this investigation are conducted using a semi-synthetic flow and reactive transport model based on physical and biogeochemical conditions from two uranium contaminated sites: the Naturita Uranium Mill Tailings Remedial Action (UMTRA) Project site in southwestern Colorado and the Old Rifle UMTRA Project site in western Colorado.</p><p>

<p> The Saint-Venant shallow water equations are commonly used to model river hydraulics. The equations utilize a hydrostatic assumption with a recommendation to limit use to a bed slope less than 1:10, vertical to horizontal. This recommended limit was made in an era when calculations were performed by hand and therefore minimized by performing a one-dimensional analysis with the distance between river stations maximized. Current technology makes a more detailed analysis accessible. </p><p> This study investigates the effects of applying a two-dimensional hydraulic model that utilizes the Saint-Venant shallow water equations without correction for non-hydrostatic conditions to a bed slope of 1:8. By doing so it was hoped to show that there exists an effective and economical method for engineers to analyze hydraulic effects in these conditions. </p><p> A comparative analysis of the results from the 2D model and a 3D non-hydrostatic model was utilized to investigate the theoretical limit of slope on the hydrostatic assumption. The models consisted of an existing 2D model previously developed for an engineering study and a 3D model developed for this study, which employed a novel approach to approximate the effects of surface roughness. The analysis compared model results for depth, velocity, and flow rate at nine cross sections on the study reach. While the findings from the research are not conclusive they do illustrate that a well resolved 2D model is able to push the 1:10 slope limit on the hydrostatic assumption for the shallow water equations. It was found that a uniform flow applied to the 2D model and allowed to come to steady state maintained a relatively consistent flow rate throughout the length of the reach. This demonstrates that the model did not produce any artificial gains or losses. Surprisingly, the 2D model accomplished this while the 3D model did not. </p><p> These findings are important in locations where the accepted methods of 3D non-hydrostatic modeling would be computationally cumbersome and cost prohibitive. The lack of efficient and affordable analysis tools rated for steep slopes leads to the construction of facilities with unknown hydraulic risk to life and property. Fully verifying the methods of this study would provide needed support to hydraulic engineers for these conditions. </p><p> Concurrent to the research for this thesis, was the development of a series of lessons on introductory hydraulic engineering for middle school students. Engineering is characterized by its hands on, real world application of science and math and is rooted in a tradition of disseminating knowledge through mentorship. Many engineering topics provide opportunity to spark the minds of our youth. The final chapter of this paper is a summary of this work. It is included it here to encourage more engineers to share their work with the next generation.</p><p>

<p> Agricultural drought is a creeping disaster that overshadows the vegetative cover in general and cropland specifically in Iraq, a country that was well known for its agricultural production and fertile soil. In the recent years, the arable lands in Iraq experienced increasing land degradation that led to desertification, economic losses, food insecurity, and deteriorating environment. Remote sensing is employed in this study and four different indices are utilized, each of which is derived from MODIS satellite mission products. Agricultural drought maps are produced from 2003 to 2015 after masking the vegetation cover. Year 2008 was found the most severe drought year during the study period, where drought covered 37% of the vegetated land. This part of the study demonstrated the capability of remote sensing in fulfilling the need of an early warning system for agricultural drought over such a data-scarce region.</p><p> This study also aims to monitor hydrological drought. The Gravity Recovery and Climate Experiment (GRACE) satellite-derived monthly Terrestrial Water Storage (TWS) is the hydrological drought indicator, that is used to calculate the deficit. Severity of drought events are calculated by integrating monthly water deficit over the drought period. In addition, drought recovery time is assessed depending on the estimated deficit. Major drought events are classified into several levels of severity by applying a drought monograph approach. The results demonstrated that GRACE TWS is a reliable indicator for drought assessment over Iraq, and provides useful information for decision makers which can be utilized in developing drought adaptation and mitigation strategies. </p><p>

<p> Recent research and technological advances in the field of hydrology and water resources call for parallel educational reforms at the undergraduate level. This thesis describes the design, development, and evaluation of a series of undergraduate learning modules that engage students in investigative and inquiry-based learning experiences and introduces data analysis and numerical modeling skills. The modules are situated in the coastal hydrologic basins of Louisiana, USA. Centered on the current crisis of coastal land loss in the region, the modules immerse students in a suite of active-learning experiences in which they prepare and analyze data, reproduce model simulations, interpret results, and balance the beneficial and detrimental impacts of several real-world coastal restoration projects. The modules were developed using a web-based design that includes geospatial visualization via a built-in map-interface, textual instructions, video tutorials, and immediate feedback mechanisms. Following pilot implementations, an improvement-focused evaluation was conducted to examine the effectiveness of the modules and their potential for advancing students&rsquo; experiences with modeling-based analysis in hydrology and water resources. Both qualitative and quantitative data was collected including Likert-scale surveys, student performance grades, informal interviews, and text-response surveys. Students&rsquo; perceptions indicated that data and modeling-driven pedagogy using local real-world projects contributed to their learning and served as an effective supplement to instruction. The evaluation results also pointed out some key aspects on how to design effective and conducive undergraduate learning experiences that adopt technology-enhanced, data and modeling-based strategies, and how to pedagogically strike a balance between sufficient module complexity, ensurance of students&rsquo; continuous engagement, and flexibility to fit within existing curricula limitations. Additionally, to investigate how such learning modules can achieve large scale adoption, a total of 100 interviews were conducted with academic instructors and practicing professionals in the field of hydrology and water resources engineering. Key perspectives indicate that future efforts should appease hindering factors such as steep learning curves, lack of assessment data, refurbishment requirements, rigidness of material, time limitations.</p><p>

<p> The Salinas River Valley Watershed has endured the effects of seawater intrusion for decades caused by overpumping groundwater from the Salinas River Groundwater Basin. The Castroville Seawater Intrusion Project began delivering recycled water in 1998 with other water sources due to wells becoming too saline. One-on-one, in-person interviews with eighteen growers, who own or lease farmland within the Project&rsquo;s service area, were conducted during a severe, statewide drought. Interview questions explored grower attitudes and concerns regarding their water supply, and the impact of management strategies on the mitigation of seawater intrusion. Two research questions were posed, exploring factors that influence grower acceptance of alternative water supplies, and whether environmental impacts affect their attitudes. Four prominent factors were found that influence grower acceptance of alternative water supplies: perceived need for water supply, changes to cost and/or water quality, information/education, and level of trust. The study also revealed three motivations of growers for choosing water supplies that do not increase seawater intrusion or contribute to adverse environmental impacts: protecting harvest/land, managing associated cost of operations, and avoiding increased regulations and/or oversight. Growers with fewer numbers of farms and smaller acreage of farmland tended to have a greater perceived need to acquire sustainable water supplies, while being more reluctant to implement water sources of lesser quality.</p><p>