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Retention and Removal of Bacterial Endospores from Common Drinking Water Distribution System Pipe MaterialsPackard, Benjamin H. 05 August 2010 (has links)
No description available.
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Molecular Microbial Ecology and Operational Evaluation of a Full-scale and Pilot-scale Biologically Active Filter for Drinking Water TreatmentWhite, Colin P. 09 August 2010 (has links)
No description available.
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Controlling disinfection by-products within a distribution system by implementing bubble aeration within storage tanksMcDonnell, Bryant E. 11 October 2012 (has links)
No description available.
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Microelectrode Investigation of Iron and Copper Surfaces Exposed to Free Chlorine Under Relevant Drinking Water ChemistriesLiggett, Jennifer 16 October 2015 (has links)
No description available.
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A Risk Assessment Framework to Evaluate the Effect of Climate Change on Drinking Water Quality / Ett ramverk för riskbedömning för att utvärdera effekten av klimatförändringar på dricksvattenkvalitetenGusain, Shivam January 2022 (has links)
The impact of climate change on drinking water is one of the fastest-growing challenges within the water sector. Microbial contamination of drinking water has been a serious issue for decades now and will exacerbate in the coming future. Until recently the impact of climate change was only evaluated qualitatively and there has been a growing need for a quantitative risk assessment. This review covers different ways of incorporating the effects of climate change into the risk assessment framework. A comprehensive search through two databases was conducted resulting in 596 citations being screened for relevance, of which 23 were confirmed as relevant. Ten risk assessment frameworks and 3 tools obtained from this review were used for the comparative study with the Swedish QMRA tool. Data from multiple frameworks and tools were extracted to identify potential additions required for the improvement of the Swedish tool. Two approaches, i.e. data-driven and process-based, were identified and the foundation for a new framework was set up. Two pathways to implement these approaches were laid out with the first being the addition of new modules to the existing tool and the second being the use of hydrodynamic and water quality models to predict the impact of climate change on infection risks.
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WC-spolning med regnvattenGyllensvärd, Niklas January 2009 (has links)
Idag spolar den stora majoriteten av alla invånare i Sverige med dricksvattnen itoaletten. Spolning med regnvatten i WC är något som på flera håll i världenanvänds flitigt främst i områden med någon slags vattenbrist. Men i Sverige harregnanvändande anläggningars popularitet inte riktigt slagit igenom ännu.Orsaken till detta kan härledas till flera faktorer. De viktigaste och de sompåverkar mest är; den goda tillgången och således låga priset på dricksvatten iSverige, samt begränsad konkurrens bland företag och återförsäljare vilket ger etthögt investeringspris på regnanvändande anläggningar för konsumenten.Fokus i detta examensarbete ligger på att göra en grundläggande analys avregnvatten och möjligheterna att genom en regnanvändande anläggning kunnaanvända regnvatten istället för dricksvatten för att spola i toaletten med.Tillvägagångssättet har varit att genom en studie av olika källor sammanställainformation relevant till ämnet regnvatten och regnvattenanvändning till WCspolning,följt av en analys och jämförelse av hur ekonomiskt hållbar enregnanvändande anläggning i ett standardhus beläget i Malmö är, i förhållande tillsamma standardhus med en traditionell dricksvattenförsörjning för WC-spolning.Resultatet av analysen visar tydligt att en regnvattenanvändande anläggning ifallet med standardhuset i dagsläget inte går att rättfärdiga ur ekonomisksynpunkt, men även att det finns möjlighet till en realistisk ekonomisk förtjänst iandra byggnader eller i framtiden. / The vast majority of the Swedish population today flushes their toilet withdrinking water. Flushing the toilet with rain water is used diligently on multiplelocations around the world, typically where there is a shortage of fresh water. InSweden though, the popularity of rain water harvesting has not yet beensuccessful. The cause of this can be deducted to several factors, where the mostimportant and the most influential are the abundant source, and therefore low cost,of fresh water in Sweden and the lack of competition among retailers, whichresults in a high investment cost of rain water harvesting equipment for theconsumer.The focal point of this Bachelor’s Degree project is to make a fundamentalanalysis of rain water and the possibilities of using rain water instead of drinkingwater for flushing the toilet. The procedure of the project has consisted of a studyof sources, a compilation of information relevant to rain water and the use of rainwater as flushing water in the toilet and an analysis of a calculated average housein Malmo, Sweden, and a comparison between a traditional toilet flushing systemand a rain water toilet flushing system of the same average house.The result of the analysis clearly shows that a rain water toilet flushing systemcan not be justified from a economical standpoint in the case of the average house,but also that there is a realistic chance of an economical profit in the future or ifused with other building types.
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One Indigenous Community's Journey Towards Water Security: A Transdisciplinary Reflection on Drinking Water Advisories and Pathways Forward / Drinking Water Advisories and Pathways ForwardLucier, Kayla Jane January 2019 (has links)
Background: Water quality in on-reserve Indigenous communities in Ontario is concerning, with issues ranging from deteriorating water quality to issues with regulation and support. As a result, many communities are placed under a Drinking Water Advisory (DWA), which, at its most severe, indicates water is not safe for use or consumption. Between 2004 and 2013, approximately 70% of all on-reserve communities in Ontario were under at least one DWA. While designed to protect physical health, DWAs have widespread impacts on health and wellbeing. However, little is known about First Nation individuals’ thoughts, feelings, and experiences living under a DWA.
Purpose: To unpack and explore the broad impacts of a Boil Water Advisory (BWA) from the perspective of community members on a reserve in Northern Ontario and provide considerations for current and future BWA management.
Methods: Methodological choices were driven by the principles of community-based participatory research. Questionnaires and interviews were used to collect data. Two hundred and twenty-six questionnaires were distributed. Fifteen Elders and 22 key informants (KIs) were contacted for an interview.
Results: Forty-four (19.5%) individuals completed a questionnaire. Eight Elders and 16 KIs participated in 20 interviews. Questionnaire sections were used to frame the data analysis, which fell under five major themes: 1) Community Context; 2) Knowledge of BWAs; 3) Living Under a BWA; 4) Water and Health; and, 5) Pathways Forward.
Conclusions: Responses illuminated gaps where education surrounding best practices for protecting health would be crucial moving forward. They also highlighted that women are an important target audience for education. Points also emerged where communication with community members and stakeholders would be key to understanding the impacts and outcomes of DWAs. Additionally, this community, and others experiencing a DWA, should consider greater involvement in water management by younger individuals, to ensure that all perspectives are adequately represented. / Thesis / Master of Public Health (MPH) / When water is known, or suspected, to be unsafe for human consumption, communities are placed under a Drinking Water Advisory (DWA). Indigenous communities have some of the worst water quality in Canada and many are subsequently under DWAs. Despite the widespread impact of DWAs on health and wellbeing, little is known about First Nation individuals’ thoughts, feelings, and experiences living under one.
The goal of this thesis was to unpack and explore the broad health, social, cultural, and economic impacts of a Boil Water Advisory (BWA) from the perspective of community members on a reserve in Northern Ontario and provide considerations for BWA management.
Responses pointed to gaps where education surrounding how to best protect health would be crucial, especially for women who were highlighted as an important target audience. Points also emerged where communication would be key to understanding the impacts and outcomes of DWAs moving forward.
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Characterisation of dissolved organic matter to optimise powdered activated carbon and clarification removal efficiencyShutova, Y., Rao, N.R.H., Zamyadi, A., Baker, A., Bridgeman, John, Lau, B., Henderson, R.K. 15 June 2020 (has links)
Yes / The character of dissolved organic matter (DOM) present in drinking water treatment systems greatly impacts its treatability by coagulation–flocculation. Powdered activated carbon dosing has been suggested to enhance DOM removal when combined with coagulation–flocculation. However, optimising powdered activated carbon (PAC) dosing requires further research. In this study, fluorescence spectroscopy combined with parallel factor analysis (PARAFAC) and liquid chromatography with organic carbon detection (LC–OCD) has been used to characterise DOM removal in three ways: (a) coagulation–flocculation–sedimentation without PAC dosing, (b) PAC dosing prior to- and (c) PAC dosing during coagulation–flocculation–sedimentation treatment. It was shown that only coagulation–flocculation–sedimentation preferentially removed biopolymer and humic substance chromatographic fractions and fluorescent DOM, whereas dosing PAC preferentially removed building blocks and low molecular weight neutral chromatographic fractions. The DOM treatability that was achieved when PAC was dosed both prior to- and during coagulation–flocculation–sedimentation was comparable, but higher than what was achieved without any PAC dosing. Introduction of PAC to the coagulation–flocculation–sedimentation process significantly improved DOM removal, with fluorescent components removed by 97%. This study also highlights that a combination of fluorescence spectroscopy and LC–OCD is essential to track the removal of both, fluorescent and non-fluorescent DOM fractions and understand their impacts on DOM treatability when using different treatment processes. Overall, lower residual DOM concentrations were obtained in the treated water when PAC adsorption and the coagulation–flocculation–sedimentation processes were combined when compared to treating the water with only one of the processes, despite differences in source water character of DOM.
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Characterization of Coliform Bacteria in Drinking Water Treatment PlantWestöö, Oskar January 2021 (has links)
Termen koliforma bakterier beskriver en grupp indikatororganismer som används för att bedöma renligheten och integriteten hos reningsverk samt distributionssystem som nyttjas vid dricksvattenproduktion. För närvarande ställer styrande förvaltningsmyndigheter endast krav på detektion av antalet koliforma bakterier i dricksvatten via odlingsbaserade metoder. Dessa odlingsbaserade metoder särskiljer och upptäcker koliforma bakterier, och Escherichia coli specifikt, baserat på deras tillväxt samt enzymatiska aktivitet på selektiva kromogena och fluorogena agarplattor. Den definition av koliforma bakterier som dessa lagstiftningar ger upphov till identifierar endast koliforma bakterier baserat på deras metabolism och enzymatiska aktivitet, vilket är otillräckligt för att taxonomiskt identifiera olika bakterier inom denna grupp. För att uppnå detta krävs en definition baserad på fylogenetik. Detta masterexamensarbete beskriver undersökandet av metoder för taxonomisk identifiering av koliforma bakterier baserade på en kombination av odlingsbaserade och molekylära metoder. Vattenprover från Mälaren och Lovös vattenverk i Stockholm användes för att isolera koliforma bakterier via membranfiltrering, följt av odling på selektiva medier. De isolerade kolonierna och membranfiltrerna användes för att extrahera genomiskt DNA, följt av amplifiering av specifika gener associerade med E. coli och koliforma bakterier via PCR. Dessa inkluderade lacZ-genen, uidA-genen, yaiO-genen och 16S rRNA-genen. Produkterna från lyckade genamplifieringar sekvenserades för att taxonomiskt klassificera sekvenserna och identifiera olika koliforma bakterier. Två vattenprover med inloppsvatten skickades även för metagenomisk analys av dess mikrobiom. Dessa resulta indikerade att ett odlingssteg var nödvändigt för att producera tillräckligt med biomassa och genomiskt DNA för att lyckas med genamplifieringar utan att behöva filtrera enorma mängder vattenprover. De utvalda primrarna uppvisade även varierande framgång i att amplifiera målgenerna hos koliforma bakterier. Bakteriekoloniernas fysiska utseende på de selektiva agarplattorna och resultaten från genamplifieringarna uppvisade inte sammanhängande resultat, vilket indikerar ett behov av att ytterligare undersöka och optimera de utförda PCR-protokollen. Trots detta visade metoden potential för taxonomisk identifiering av koliforma bakterier. 16S rRNA-gensekvenserna möjliggjorde identifieringen av potentiella kontaminanter som grampositiva bakterier (Micrococcus and Staphylococcus) och andra, icke-koliforma, gramnegativa bakterier (Pseudomonas and Aeromonas) på de selektiva agarplattorna. Denna information kombinerat med bakteriekoloniernas utseende på agarplattorna och resultaten från övriga genamplifieringar kan möjliggöra ett sätt att skilja på falska positiva, falska negativa, sanna positiva och sanna negativa resultat från nuvarande detektionsmetoder för koliforma bakterier. Ytterligare optimering av olika aspekter av metoderna och arbetsflödet kring identifiering av koliforma bakterier är nödvändig innan man kan införa ett liknande tillvägagångssätt i ett reningsverk. / The term coliform bacteria describes a group of indicator organisms used to measure the cleanliness and integrity of drinking water treatment plants and distribution systems. Currently, the only legal requirement set by government agencies pertains to the detection and enumeration of these bacteria via cultivation-based methods. These methods distinguish coliform bacteria and Escherichia coli based on their growth and enzymatic activity on selective chromogenic and fluorogenic agar plates. However, the legislative definition concerning their metabolism and enzymatic production is insufficient to identify bacteria within this group taxonomically. Instead, a definition based on phylogenetics is required. This master’s thesis describes the exploration of methods for the characterization and identification of coliform bacteria via a combination of cultivation-based and molecular methods. Water samples from Lake Mälaren and the Lovö drinking water treatment plant in Stockholm were used to isolate coliform bacteria via membrane filtration and cultivation on a selective agar medium. The isolated colonies and filtered membranes were subjected to DNA extraction, followed by gene amplification of target genes associated with E. coli and coliform bacteria via PCR. This included the lacZ gene, the uidA gene, the yaiO gene, and the 16S rRNA gene. Successful gene amplicons were sent for sequencing to assign taxonomic values to the sequences and identify coliform bacteria. Two inlet water samples were also sent for metagenomic analysis of the microbiome. An incubation step was necessary to gather enough biomass to extract sufficient genomic DNA for gene amplifications and avoid the need to filtrate large volumes of water. The selected primer pairs exhibited various degrees of success in amplifying the targeted genes of coliform bacteria. The physical appearance of coliform colonies on the selective chromogenic agar plates and the results from the gene amplifications displayed no discernable pattern, indicating the need to further investigate and optimize the PCR procedures. However, the method indicated a potential for coliform bacteria identification. 16S rRNA gene sequences allowed for the distinction of potential contaminants on the selective agar media in gram-positive bacteria (Micrococcus and Staphylococcus) and other non-coliform, gram-negative bacteria (Pseudomonas and Aeromonas). In conjunction with the physical appearance of bacterial colonies on selective media and successful gene amplicons of the targeted genes, this information could allow one to distinguish between false positive, false negative, true positive, and true negative results from current coliform detection and enumeration methods. Further optimization of various aspects of the coliform bacteria identification methods is necessary before introducing a similar approach to a water treatment plant context.
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Surface Enhanced Raman Spectroscopy as a Tool for Waterborne Pathogen TestingWigginton, Krista Rule 25 November 2008 (has links)
The development of a waterborne pathogen detection method that is rapid, multiplex, sensitive, and specific, would be of great assistance for water treatment facilities and would help protect water consumers from harmful pathogens. Here we have utilized surface enhanced Raman spectroscopy (SERS) in a sensitive multiplex pathogen detection method. Two strategies are proposed herein, one that utilizes SERS antibody labels and one that measures the intrinsic SERS signal of organisms. For the SERS label strategy, gold nanoparticles are conjugated with antibodies specific to Cryptosporidium parvum and Giardia lamblia and with organic dye molecules. The dye molecules, rhodamine B isothiocyanate (RBITC) and malachite green isothiocyanate (MGITC) were surface enhanced by the gold nanoparticles resulting in unique fingerprint SERS spectra. The SERS label method was successful in detecting G. lamblia and C. parvum simultaneously. The method was subsequently coupled with a filtration step to both concentrate and capture cysts on a flat surface for detection. Raman mapping across the filter membrane detected ~95% of the spiked cysts in the optimized system.
In the second type of strategy, intrinsic virus SERS signals were detected with silver nanoparticles for enhancement. Principal component analysis performed on the spectra data set resulted in the successful differentiation of MS2 and PhiX174 species and also for the differentiation of viable virus samples and inactivated virus samples. / Ph. D.
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