Lack of access to drinking water remains widespread as 2.1 billion people live without safely managed service that includes improved water sources located on premises, available when needed, and free from contamination. Monitoring global access to drinking water is complex, yet essential, particularly in settings where households need to fetch water to meet their basic needs, as multiple factors that relate to accessibility, quantity and quality ought to be considered. The overall objective of this observational study is to increase knowledge surrounding monitoring and assessment of access to drinking water supply in low-and middle-income countries. The dissertation was comprised of five manuscripts which address the objective using various approaches including systematic review (manuscript 1), secondary data analysis (manuscript 2), and primary data analysis (manuscripts 3-5) to gather evidence towards improving access to drinking water. Primary data were collected through a seasonal cohort study conducted in Southern Malawi that included 375 households randomly selected in three different urban and rural sites. Methods used included structured questionnaires, observations, GPS-based measurements, and water quality testing. Findings from this study highlight the importance of conducting appropriate assessment of household behaviours in accessing drinking water in view of improving reliability of the indicators and methods used to monitor access to water. Seasonal variations that may affect water sources' reliability and household’s needs should be put forward to improve benefits of improving access to water and sustainable health outcomes. Further to target reliable and continuous availability from an improved water source at proximity to the household, interventions should aim to ensure safe quality of water at the point of use for mitigating the effect of post-collection contamination, and ensure sufficient quantities of water to allocate for personal and domestic hygiene. Focusing on the benefits of improving access to water at the point of consumption is essential to generate more realistic estimations, suitable interventions and appropriate responses to need. / Graduate

Groundwater contamination is a concern due to the large number of people that can become exposed to the contaminant. The chemicals benzene and phenol are known groundwater contaminants. The main health problem caused by benzene or phenol is bone marrow toxicity. Benzene and phenol are also immunotoxins reported to cause decreased thymic weights, altered lymphocyte mitogenic responses, and lower antibody production. Cytokines are key signaling molecules produced by the cells of the immune system to activate other cells in the immune system, produce antibodies, and recruit other cells to sites of inflammation. The purpose of this study was to determine if exposure to benzene or phenol in drinking water for 30 days could lead to alterations in IL-l, IL-6, and TNFa production in in vitro activated murine macrophages, or in IL-2, IL-3, and IFNy production in in vitro activated murine lymphocytes. Cytokine mRNA and protein production were evaluated to determine if any alteration occurred. Benzene and phenol exposure resulted in significantly decreased thymus weights. Interleukin-2 mRNA production was increased at the medium dose (200 mg/L) but the IL-2 protein secreted from the lymphocytes of benzene-treated mice was unchanged. The macrophages from benzene-treated mice showed a decrease at all dosage levels in both TNFa mRNA and protein production. These macrophages also produced increased JLIa mRNA at the medium benzene concentration, although this increase did not mean an increase of IL-Ia protein secreted. Mice given phenol at the medium (20 mg/L) and high (100 mg/L) dosages had decreased 30-day body weights. The production ofiL-3 mRNA was decreased in the lymphocytes of mice receiving both low and high concentrations of phenol. Lowered TNFa mRNA values were observed in the macrophages from phenoltreated mice. Interleukin-la mRNA production was increased in the macrophages of mice given the low (5 mg/L) dose of phenol. The TNFa cytokine protein was decreased at the low and medium doses, and the IL-l a protein level was decreased at the medium and high doses. The results indicate that benzene and phenol in groundwater should continue to be a concern for public and regulatory agencies.

Previous authors have developed many different types of water pipe condition and failure models using the various methodologies available.  Contrary, current utilities are struggling to maintain their current water infrastructure system, due to the lack of effective prediction tools at hand.  The gap between the methodologies available in academic research and the tools available to current water utilities needs to be addressed.  This paper presents a fuzzy inference prediction model used to forecast the performance rating of individual drinking water pipeline sections (node to node) in which utilities can easily apply to their drinking water infrastructure system. Prior to the development of a prediction model, a through literature and current practice review is completed detailing and summarizing all the available mathematical models.  Following, an infrastructure overview is presented detailing the various pipe materials, lifecycle and failure modes and mechanisms.  A data structure is also detailed which lists all parameters that affect the condition and/or performance of a pipeline.  All of these tools are successfully used to develop a fuzzy inference performance model. The fuzzy inference performance model is considered novel in that it considers close to 30 pipe parameters.  Moreover, the performance model is applied using the Western Virginia Water Authority (WVWA) and the Washington Suburban Sanitary Commission (WSSC) databases to evaluate and verify the predicting results.  Lab testing of several pipe samples is also used to evaluate the model.  The testing consists of a ring bearing test which is used to calculate the rupture modulus of the pipe.  Comparing the original vs. the current rupture modulus can determine the remaining strength of the pipe.  The remaining strength can then be used to assess the performance results predicted by the fuzzy inference model. Further a framework is set forth which utilizes the model's predicted performance ratings to develop deterioration curves which can be used as a tool to forecast and plan future inspection, repair, rehabilitation and replacement of water pipelines.  The deterioration model is made up of a Markov chain approach coupled with a non-optimization technique. / Ph. D.

This thesis aims to address factors affecting the sustainability of development projects focusing on water supply in Ethiopia. The thesis identifies main dimensions of sustainability and examines factors within them and their impact on long-term functionality of the studied interventions. The research focuses on the (un)sustainability of the selected water supply projects in Sidama and Alaba, Ethiopia. Ten water supply systems constructed under three projects supported from the Czech development cooperation were examined. Data were collected through semi-structured interviews and direct observations of analyzed water systems. The interviews were conducted with experts, representatives of the implementing organization, representatives of water institutions in Ethiopia (Woreda Water Offices and WASH Committees) and recipients of the interventions, i.e. users of the water supply systems. This was supplemented by the analysis of project documentation. Field research in Ethiopia was conducted in November 2020 and lasted four weeks. The results showed ongoing long-term functionality with only minor problems in the majority of studied systems. One system was nonfunctional at the time of visit and two systems were facing serious problems. The sustainability of studied systems was affected mainly by...

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20692号 / 工博第4389号 / 新制||工||1682(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 高岡 昌輝, 教授 藤井 滋穂 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

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No description available.

The removal of 34 per- and polyfluoroalkyl substances (PFAS) were compared in a 1 stagegranular activated carbon (GAC) filtration to a 2 stage GAC filtration in a pilot study at adrinking water treatment plant (DWTP). The PFASs that were present in the water wereperfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluoropentanoic acid(PFPeA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorobutanesulfonic acid (PFBS), perfluoropentane sulfonic acid (PFPeS) and perfluorohexane sulfonic acid(PFHxS). A cost comparison for the operation of a one stage GAC to a two stage GAC wascompared for PFAS4 (sum of PFOA, PFNA, PFHxS and PFOS) at treatment goals ranging from2 - 10 ng/L. The pilot was operated at three different flows and the three different bed volumes(BV)s resulting in three different empty bed contact times (EBCTs) at three different times.Therefore, the Lin & Huang adsorption model (1999) was used to model the concentrations ateach EBCT. It was found that the model worked good for PFBS, PFPeS, PFHxS, PFOS andPFOA but not for PFPeA, PFHxA and PFHpA (except for PFPeA and PFHxA during EBCT 5min) and did not work for desorbing PFASs. The removal comparison of PFASs was made,partly by comparing removal efficiencies between the first stage and the second stage GAC filterand by comparing the removal per weight of GAC per BV 1 stage and 2 stages. It was found thatthe removal efficiency decreases with decreasing chain length and increasing treated BVs forboth the first stage and the second stage. The short chain PFCAs were also desorbing after anumber of BVs. The removal per weight of GAC showed that the removal does not increasewhen comparing a one stage GAC to a two stage GAC for any the PFAS. The cost comparisonwas made using the adsorption model. It showed that it was cheaper to operate a 2 stage GAC forthe EBCT of 5 minutes and 8 minutes for the whole range of treatment goals. However, for theEBCT of 15 minutes the costs for the second stage was decreasing with decreasing treatmentgoal which is unrealistic result. This was caused by too few data points available for the model topredict reliable results.

京都大学 / 新制・論文博士 / 博士(工学) / 乙第13495号 / 論工博第4202号 / 新制||工||1786(附属図書館) / (主査)教授 米田 稔, 教授 高野 裕久, 教授 松井 康人 / 学位規則第4条第2項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

The existence of trihalomethanes (THMs) in a drinking water plant of Nicaragua has been investigated in order to see whether the concentration exceeded the maximum contaminant level recommended by the environmental protection agency of the United States (USEPA) and the Nicaragua guidelines. The influence of pH, temperature, chlorine dose and contact time on the formation of THMs were studied. The contents of organic matter measured by surrogate parameters such as total organic carbon, dissolved organic carbon, ultraviolet absorbance and specific ultraviolet absorbance were also determined in order to show which type of organic matter is most reactive with chlorine to form THMs. Models developed by other researchers to predict the formation of trihalomethanes were tested to see whether they can be used to estimate the trihalomethane concentration. In addition, empirical models were development to predict the THM concentration of the drinking water plant analysed. The raw water was treated by conventional and enhanced coagulation and these processes were compared with regard to the removal of natural organic matter (NOM). The significance of the results was assessed using statistic procedures. The average concentration of THMs found at the facility is below the USEPA and Nicaragua guideline values. Nevertheless the maximum contaminant level set by USEPA is sometimes exceeded in the rainy season when the raw water is rich in humic substances. Comparison between the water treated by conventional and enhanced coagulation shows that enhanced coagulation considerably diminished the trihalomethane formation and the value after enhanced coagulation never exceeded the guidelines. This is because enhanced coagulation considerably decreases the organic matter due to the high coagulant dose applied. The study of the trihalomethane formation when varying pH, time, temperature and chlorine dose using water treated by conventional and enhanced coagulation showed that higher doses of chlorine, higher pH, higher temperature and a longer time increases the formation of THMs. However, combinations of two and three factors are the opposite. The predicted THM formation equations cannot be used for the water at this facility, since the results shown that the measured THM differs significantly from the THM concentration predicted. Two empirical models were developed from the data for enhanced coagulation, using linear and non-linear regression. These models were tested using the database obtained with conventional coagulation. The non-linear model was shown to be able to predict the formation of THMs in the Boaco drinking water plant. / QC 20101129