abstract: ABSTRACT Water resources in many parts of the world are subject to increasing stress because of (a) the growth in demand caused by population increase and economic development, (b) threats to supply caused by climate and land cover change, and (c) a heightened awareness of the importance of maintaining water supplies to other parts of the ecosystem. An additional factor is the quality of water management. The United States-Mexican border provides an example of poor water management combined with increasing demand for water resources that are both scarce and uncertain. This dissertation focuses on the problem of water management in the border city of Ciudad Juarez, Chihuahua. The city has attracted foreign investment during the last few decades, largely due to relatively low environmental and labor costs, and to a range of tax incentives and concessions. This has led to economic and population growth, but also to higher demand for public services such as water which leads to congestion and scarcity. In particular, as water resources have become scarce, the cost of water supply has increased. The dissertation analyzes the conditions that allow for the efficient use of water resources at sustainable levels of economic activity--i.e., employment and investment. In particular, it analyzes the water management strategies that lead to an efficient and sustainable use of water when the source of water is either an aquifer, or there is conjunctive use of ground and imported water. The first part of the dissertation constructs a model of the interactive effects of water supply, wage rates, inward migration of labor and inward investment of capital. It shows how growing water scarcity affects population growth through the impact it has on real wage rates, and how this erodes the comparative advantage of Ciudad Juarez--low wages--to the point where foreign investment stops. This reveals the very close connection between water management and the level of economic activity in Ciudad Juarez. The second part of the dissertation examines the effect of sustainable and efficient water management strategies on population and economic activity levels under two different settings. In the first Ciudad Juarez relies exclusively on ground water to meet demand--this reflects the current situation of Ciudad Juarez. In the second Ciudad Juarez is able both to import water and to draw on aquifers to meet demand. This situation is motivated by the fact that Ciudad Juarez is considering importing water from elsewhere to maintain its economic growth and mitigate the overdraft of the Bolson del Hueco aquifer. Both models were calibrated on data for Ciudad Juarez, and then used to run experiments with respect to different environmental and economic conditions, and different water management options. It is shown that for a given set of technological, institutional and environmental conditions, the way water is managed in a desert environment determines the long run equilibrium levels of employment, investment and output. It is also shown that the efficiency of water management is consistent with the sustainability of water use and economic activity. Importing water could allow the economy to operate at higher levels of activity than where it relies solely on local aquifers. However, at some scale, water availability will limit the level of economic activity, and the disposable income of the residents of Ciudad Juarez. / Dissertation/Thesis / Ph.D. Sustainability 2011

abstract: The rights of American Indians occupy a unique position within the legal framework of water allocations in the western United States. However, in the formulation and execution of policies that controlled access to water in the desert Southwest, federal and local governments did not preserve the federal reserved water rights that attached to Indian reservations as part of their creation. Consequentially, Indian communities were unable to access the water supplies necessary to sustain the economic development of their reservations. This dissertation analyzes the legal and historical dimensions of the conflict over rights that occurred between Indian communities and non-Indian water users in Arizona during the second half of the twentieth century. Particular attention is paid to negotiations involving local, state, federal, and tribal parties, which led to the Congressional authorization of water rights settlements for several reservations in central Arizona. The historical, economic, and political forces that shaped the settlement process are analyzed in order to gain a better understanding of how water users managed uncertainty regarding their long-term water supplies. The Indian water rights settlement process was made possible through a reconfiguration of major institutional, legal, and policy arrangements that dictate the allocation of water supplies in Arizona. / Dissertation/Thesis / Ph.D. History 2011

abstract: The goal of the study was twofold: (i) to investigate the synthesis of hematite-impregnated granular activated carbon (Fe-GAC) by hydrolysis of Fe (III) and (ii) to assess the effectiveness of the fabricated media in removal of arsenic from water. Fe-GAC was synthesized by hydrolysis of Fe(III) salts under two Fe (III) initial dosages (0.5M and 2M) and two hydrolysis periods (24 hrs and 72 hrs). The iron content of the fabricated Fe-GAC media ranged from 0.9% to 4.4% Fe/g of the dry media. Pseudo-equilibrium batch test data at pH = 7.7±0.2 in 1mM NaHCO3 buffered ultrapure water and challenge groundwater representative of the Arizona Mexico border region were fitted to a Freundlich isotherm model. The findings suggested that the arsenic adsorption capacity of the metal (hydr)oxide modified GAC media is primarily controlled by the surface area of the media, while the metal content exhibited lesser effect. The adsorption capacity of the media in the model Mexican groundwater matrix was significantly lower for all adsorbent media. Continuous flow short bed adsorber tests (SBA) demonstrated that the adsorption capacity for arsenic in the challenge groundwater was reduced by a factor of 3 to 4 as a result of the mass transport effects. When compared on metal basis, the iron (hydr)oxide modified media performed comparably well as existing commercial media for treatment of arsenic. On dry mass basis, the fabricated media in this study removed less arsenic than their commercial counterparts because the metal content of the commercial media was significantly higher. / Dissertation/Thesis / M.S.Tech Applied Biological Sciences 2011

Esta Tese analisa os condicionantes, os limites e as possibilidades postos à efetivação de uma gestão efetivamente integrada em bacias hidrográficas de dupla dominialidade, contextualizando tais questões ao modelo de gestão em implantação no Brasil a partir do início da década de 90. O trabalho está focado na gestão das águas da bacia do Rio Paraíba do Sul, analisando o processo histórico de construção do sistema e seus impactos nas estratégias de convivência entre os dois diferentes organismos atuantes no trecho paulista da bacia: o Comitê da Bacia Hidrográfica do Rio Paraíba do Sul (CBH-PS), responsável especificamente pela gestão no trecho paulista da bacia; e o Comitê para a Integração da Bacia do Rio Paraíba do Sul (CEIVAP), com jurisdição sobre a totalidade da bacia. O marco conceitual deste estudo apóia-se, principalmente, nas contribuições de autores situados no campo reconhecido como neoinstitucionalista. Promoveu-se um minucioso resgate do processo de implantação das diferentes “instituições políticas” relacionadas à gestão das águas da bacia, contextualizando assim o “processo político” de convivência entre os dois modelos de gestão retratados, abrindo-se dessa maneira perspectivas mais amplas para a análise dos conteúdos e dos impactos decorrentes dessas políticas. Para o adequado desenvolvimento deste estudo foi realizado o acompanhamento – tanto documental, quanto presencial - das atividades de ambos os Comitês. A pesquisa está também apoiada em entrevistas com um amplo conjunto de informantes centrais. O relato do histórico da gestão no trecho analisado foi organizado em cinco períodos, retratando movimentos de conflito e cooperação entre os atores. Apesar dos diversos desafios ainda a serem enfrentados rumo à integração, os dados coletados apontam para um gradual avanço na maturidade do sistema de gestão de recursos hídricos, com perspectivas positivas rumo à implantação de ações coordenadas e cooperativas na bacia. Esse movimento também explicita a dimensão temporal como um importante fator a ser considerado no processo de mudança institucional. / This study examines the possibilities and the restraints of the estabilishent an effective Integrated Water Resource Management System in the Paraiba do Sul River Basin in the context of the new Brasilian water management policy started in the 1990s. The research focused on the institutional an jurisdictional complexity of this management, particularly in the São Paulo State section. This study analyzes those institutional frameworks, their articulations and overlaps, and the outcomes on sustainable water use. The research was based on documental analysis and interviews. The management history report of the analyzed section was organized into 5 moments, depicting points of contention and cooperation among the ones involved. The gathered data point to a gradual improvement in the evolution of Integrated Water Resource Management System with positive perspectives towards the implementation of coordenated and cooperative actions in the Basin.

A otimização do uso da água é um desafio para os gerenciadores, pois o planejamento da irrigação requer cuidados especiais, a fim de compatibilizar o balanço hídrico com a demanda, tanto no que se refere à quantidade como a sua repartição espacial e temporal. Técnicas de otimização têm sido empregadas nas recentes décadas para tratar problemas de planejamento e manejo de sistemas de recursos hídricos. O objetivo do presente trabalho consistiu em propor planos ótimos de cultivos, utilizando modelos de programação linear que proporcionem a maximização do retorno líquido do Perímetro de Irrigação Formoso, especificamente quanto a área de lotes familiares. Os modelos utilizados neste estudo foram baseados nos dados que compõem os Relatórios de Monitoria Ano Agrícola de 2008 e 2009 da 2ª Superintendência Regional da CODEVASF, Relatório do Distrito de Irrigação do Projeto Formoso e em informações adicionais fornecidas pela referida empresa pública. O modelo estudado é uma formulação-padrão de programação linear, cuja função-objetivo consistiu em maximizar a receita líquida do projeto, utilizando-se as culturas mais cultivadas nessa área, sob regime de irrigação. Com base nas culturas consideradas e suas respectivas funções de resposta à água, nas restrições de área cultivada, nos preços e nos custos de produção, os resultados permitem as seguintes conclusões: A maximização da receita líquida no Perímetro Irrigado Formoso foi obtida com o modelo de lâminas alternativas, com um retorno financeiro de R$ 68.384.956,53, utilizando o seguinte padrão de cultivo: 30 ha de abóbora, 30 ha de feijão Phaseolus, 977 ha de melancia, 1868 ha de banana, 1200 ha de mamão e 300 ha de limão Tahiti, para o volume anual de 79.649.300 m3. Em qualquer nível de volume de água disponível os valores das lâminas de água foram maiores no modelo lâminas fixas do que no modelo lâminas alternativas. / The optimization of water use is a challenge for managers, because the planning of irrigation requires special care to reconcile the water balance with demand, both in terms of quantity as spatial and temporal distribution. Optimization technique have been employed in recent decades to address problems of planning and management of water resources systems. The aim of this study was to propose optimal crop plans, using linear programming models, providing the maximization of net return on Formoso Irrigation District, regarding the area of farming family. The models used in this study were based on data of the Reports Agricultural year 2008 and 2009 of the 2th Regional Superintendent of CODEVASF and additional information submitted by that government department. The studied model is a traditional linear programming formulation, in which the objective function consisted into maximizing the net income of the project using the most cultivated crops in the area, under irrigation conditions. Based on the crops considered and their response functions to water restrictions on acreage, prices and production costs, the results allow the following conclusions: the maximization of net revenue in Formoso Irrigation District was obtained with the model of alternative irrigation depths, with a payback of R $ 68,384,956.53, using the following crop pattern: 30 ha of squash, 30 ha of Phaseolus beans. 977 ha of watermelon, 1868 ha of banana, 1200 ha of papaya and 300 ha of Tahiti lime, for the annual volume of 79,649,300 m3. At any level of available water the irrigation depths in the model fixed was higher than the irrigation depths in the model alternatives.

Few studies have attempted to determine the tenability of Community Participation (CP) theory is explicating Water Production and Management dynamics in Urban Informal Settlements. Consequently, several gaps exist in knowledge of the value of this important theory for efforts to improve water service delivery in such settlements. The main purpose of this study is to contribute to efforts addressed to filling these gaps. Four water schemes established by Sustainable Aid in Africa International in partnership with different communities in the informal neighborhoods of Kisumu Kenya are used as empirical referent. The study is guided by the following three Research Questions; 1) what is the relationship between community participation and beneficiary satisfaction with the work of the water management committees in the four schemes? 2) what are the contributions (positive or negative) of community participation on the production of clean potable water supply in the informal settlements? 3) what are the participation-related factors affecting the performance of the schemes? Uncovering answers to these questions entailed the use of a mixed methods approach. The approach involved the application of both quantitative and qualitative techniques. The former was employed mainly to answer the first two Research Questions and latter to deal with Research Question Three. The quantitative component of data collection involved administering a survey questionnaire through a simple random sampling technique. Logistic Regression and Chi-square Tests were employed to analyze the quantitative data. In the qualitative phase, Focus Group Discussions, Observation, Transect Walks and Photographic evidence was used to collect data analyzed through Constant Comparison Analytic technique. For Research Question One, the logistic regression results indicate that five participatory variables are significantly associated with beneficiary satisfaction with the work of the water management committees. These are provision of paid or unpaid labor to the water schemes, household willingness to intervene against pipe vandalism, meeting attendance, willingness to contribute money or time to the community water scheme and whether a household has ever made a complaint about water supply/quality issues. For Research Question Two, the chi-square test shows that households who use community managed water schemes and attend water and sanitation meetings tend to practice better water handing hygiene in the settlements. For Research Question Three, the following factors are identified to be either aiding and/or impeding the success of the schemes; networking and collaboration, continuous community engagement/participation, the formation of water consumer groups, coordination and organizational management, extent of institutional formalization, provision of dividends to the community, clannism, population increase, and poverty and community fatigue. This dissertation sheds new light on the role played by CP in managing vital resources such as water in urban informal settlements/neighborhoods. An important policy contribution is that CP can be used as a viable strategy in the establishment of effective water schemes in urban informal settlements. Furthermore, it can act as an antidote with regards to water quality improvements in urban informal settlements/neighborhoods.

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 remain about virus removal efficiency in WSPs and there is currently no mechanistic or empirical model that reliably predicts virus removal in WSPs. The overall objective of this thesis research was to model the extent of virus removal in individual waste stabilization ponds to support the reuse of wastewater. A literature review was used to create a database of estimated apparent virus removal rate coefficients (Kv,app) in three different WSP types (anaerobic, facultative, and maturation ponds). The database consisted of 249 paired influent and effluent concentrations of enteric viruses or bacteriophages from 44 unique WSP systems, comprised of 112 individual WSPs from 19 different countries. Apparent virus removal rate coefficients (Kv,app) were calculated for each individual WSP using the following three mathematical models from reactor theory: complete mix, plug flow, and dispersed flow. Pearson’s correlation analysis was used to determine correlations between Kv,app values and the following design, operational, and environmental parameters: solar radiation, air temperature, pond depth, hydraulic retention time (HRT), and virus loading rates. The median Kv,app values were greater for anaerobic ponds than for facultative and maturation ponds; however, Kv,app values in facultative and maturation ponds had more significant correlations with design, operational, and environmental parameters. Additionally, Kv,app values appear to be significantly different for various types of enteric viruses and bacteriophages. Alternative multiple linear regression equations were developed to predict Kv,app values using the design, operational, and environmental parameters as explanatory variables. Analysis of variance (ANOVA) tests were used to select the most appropriate multiple linear regression equations with the least amount of explanatory variables. The most appropriate plug flow and dispersed flow multiple linear regression equations for predicting Kv,app values included air temperature and HRT as explanatory variables. The results indicate that the plug flow regression equation was able to better predict Kv,app values (R2 = 0.38) than the dispersed flow regression equation (R2 = 0.24) in facultative and maturation ponds based on the dataset. However, both the dispersed flow and plug flow models had R2 values of approximately 0.84 when they were used to predict effluent virus concentrations in facultative and maturation ponds based on the dataset. According to this research, the plug flow regression equation is recommended for predicting apparent virus removal rate coefficients in WSPs. However, a multi-model approach that utilizes both the plug flow and dispersed flow models may yield a more robust mathematical model that can improve WSP design, reliably predict virus removal in WSPs, and ultimately be used to support wastewater reuse.

The purpose of this study was to assess whether nutrient absorption rates by water hyacinths are affected by low-salinity levels. In a controlled experiment, water hyacinths demonstrated the ability to absorb a significant amount of nutrients in low-saline waters while maintaining a slowed growth rate and shortened life span. Nutrient rates were reduced by an average of 36% in ammonia nitrogen and 48% in reactive phosphorus in the tanks of 4.45 parts per thousand (ppt) salinity. Growth rate in the experimental tanks of 4.45 ppt was observed at 33% slower than that of the control. The high salinity comparison tank of 7.0 ppt experienced complete mortality after three days. Phytoremediation practices through the use of an aquatic invader, water hyacinths, can be used to reduce large-scale fish kills along the eastern U.S.’s major estuarine systems, focusing on Florida’s waters. Toxic dinoflagellates and other harmful algal blooms have been plaguing the contributing waterways of North Carolina and the Chesapeake Bay and are the main causes of these massive fish kills. The characteristics and trends that these upstream estuarine systems are following could serve as a warning for Florida. An analysis of Florida’s fish kill database, as well as patterns and trends of the fish kills in North Carolina and the Chesapeake Bay, were used to determine areas at an increased risk for toxic dinoflagellates and harmful algal blooms to occur. Areas are proposed for water hyacinths to be implemented in a controlled method to reduce massive fish kills in Florida’s waters.

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, leaving a residual signal of random variation and possible inflow. The groundwater infiltration (as base infiltration, BI) was calculated using the Stevens-Schutzbach method, and daily wastewater flow curves were generated from dry weather flow (DWF) data. Filtered DWF values were used to construct a range of expected residuals, encompassing 95% of the variability inherent in the system. Filtered wet weather flows were compared to this range, and values above the range were considered significant, indicating the presence of surface inflow. At all 3 flow meters in the pilot study site, no surface inflow was detected, and the I/I was attributed to groundwater infiltration (as BI). Flow data from 2 smaller sub-sewersheds within the greater sewershed allowed analysis of the spatial variability in BI and provided a method to focus in on the most problematic areas. In the sub-sewershed with the shallowest water table and most submerged sanitary sewer infrastructure, an average of 56% of the average daily flow consisted of groundwater, compared to 44% for the entire study site. Cross-correlation analysis suggests that rain impacts the water table for up to 9 days, with the highest impact 1 to 3 days after rain events, and the water table, in turn, impacts infiltration for up to 6 days. The highest correlation between rainfall and infiltration occurs 3 to 5 days after a rain event, which corroborates observations from Pinellas County that severe flows to the reclamation facility continue for 3 to 5 days after severe storms. These results were used to build a linear regression model to predict base infiltration (per mile of pipeline) during the wet season using the previous 7 days of daily rainfall depths. The model tended to under-predict infiltration response to large storm events with a R2 value of 0.52 and standard error of regression of 5.3. The results of the study show that inflow can be detected using simple time series analysis instead of traditional smoke and dye testing. In this study site, however, groundwater infiltration is the only significant source of I/I. Additionally, water table and sewer invert elevations serve as useful indicators of potential sites of groundwater infiltration. Infiltration can be modeled as a function of the previous 7 days of rainfall, however simple linear regression cannot fully capture the complexity of the system response.

Garbage & sewage runoff into the Pacific Ocean at the shoreline along the U.S./Mexico Border region poses serious health and environmental threats. The purpose of this study was to analyze the current beach users’ behavioral factors that may be linked to illness prevalence from Coronado Island to the U.S./Mexico border at Imperial Beach in San Diego County. It is a continuation of a study completed by Wildcoast and Imperial Beach Clinic in 2011. The study tried to answer the following two major questions: How have the number of illnesses reported by users along South San Diego County beaches changed in the last 5 years? What relationships exist between reported illness and beach user behavior, if any? To accomplish this, a 2-page self-reporting survey was administered asking about demographics, beach recreation habits, illness and exposure information, and allowed for comments. Surveys were distributed to beach users along Imperial Beach northward to Coronado Island during May, June, and July of 2014. Quantitative as well as qualitative data were collected. The results show that the majority of respondents did not report suffering from an illness, however, for those who did report an illness, frequency of water entry, seasonality of water entry, entry during beach closures, and primary means of water contact were significantly correlated to illness prevalence.