To protect public health, detection and treatment technologies have been improved to monitor and inactivate pathogens in drinking water. The goal of this dissertation is to evaluate and utilize multiple online sensors and advanced oxidation processes to document both the detection as well as destruction of microbial contaminants in real-time. Reviews of rapid detection technologies for real-time monitoring of pathogens in drinking water and advanced technologies to inactivate pathogens in water are shown in Appendices A and B. The study in Appendix C evaluated the efficacy of real-time sensors for the detection of microbial contaminants. Bacillus thuringiensis was used in this research as a surrogate for Bacillus anthracis to determine each sensor response and detection capability. The minimum threshold responses of sensors were determined by injecting B.thuringiensis into deionized (DI), raw (unfiltered) tap water, or filtered tap water over a concentration range of 10² - 10⁵ spores/ml. The BioSentry sensor responded to increases in concentration over the range of 10² - 10⁵ spores/ml. Below this range, sensors provided signals undistinguishable from background noise. The select sensors can detect microbial water quality changes, and these advanced technologies can be integrated to monitor intrusion events in water distribution systems. The study in Appendix D evaluated the efficiency of the UV reactor for inactivation of MS2 coliphage. The virus MS2 coliphage (ATCC 15597-B1) has been proposed by the U.S. Environmental Protection Agency as a standard for UV reactor validation in the United States. In addition, MS2 is used as a surrogate for enteric viruses due to its similar size and morphology. Following UV radiation at a flow rate of 2gpm, infective MS2 showed a reduction of 5.3- log₁₀ when quantified with cultural plaque counts, whereas corresponding quantitative polymerase chain reaction (qPCR) data showed only a 1.7- log₁₀ reduction in viral RNA copy number. In contrast, plaque assay revealed a 5.8- log₁₀ inactivation; a slight increase in infective MS2 coliphage reduction at 1 gal per min but qPCR results indicate a 2.8- log₁₀ reduction in viral RNA copy number; a one log more inactivation compared to 2 gpm. When H₂O₂ was added at either 2.5 or 5 mg/l with UV at either flow rate, enhanced MS2 inactivation occurred with a greater than 7 log₁₀ reduction observed via plaque counts, indicating that all added MS2 had been inactivated, since no plaques were formed after incubation at 37°C for 24 hours. Correspondingly, qPCR data only showed a 3-4 log₁₀ reduction in viral RNA copy number. The study in Appendix E utilized online sensor to document the destruction of E.coli and Bacillus thuringiensis spores by UV/H₂O₂ treatment. In this study, Escherichia coli was tested for potential UV/H2O2 treatment in DI water and online sensors were also integrated to monitor the destruction in real-time. Pilot-scale experiments were performed using a Trojan UVSwift SC reactor (Trojan Technologies, London, ON, Canada) at a flow rate of 1 gal./min (gpm). UV radiation and UV/H₂O₂ combination in E.coli cell suspensions resulted in a >6 log₁₀ reduction of the viable counts. Similar exposure to B.thuringiensis spores resulted in a 3 log₁₀ reduction in viable counts. Scanning electron microscopy of the treated samples revealed severe damage on the surface of most E.coli cells, yet there was no significant change observed in the morphology of the B. thuringiensis spores. Following UV/H₂O₂ exposure, the BioSentry sensor showed an increase in the unknown, rod and spores counts, and did not correspond well when compared to viable counts assays. Data from this study show that advanced oxidation processes effectively inactivate E. coli vegetative cells, but not B.thuringiensis spores which were more resistant to UV/H₂O₂.

This work includes experimental examination of the hypothesis, affirming that bacteria’s, oxidising iron and manganese can grow in some Lithuanian water treatment and can increase the removal of iron and manganese substances from the water. The novelty is that the method of identification and cultivation of iron bacteria’s presented in the foreign scientific publications was improved and adapted to research of such micro-organisms existing in the quartz sand filter media in the Lithuanian equipment of water treatment plant. For the first time in Lithuania there was examined quantitative distribution of iron and manganese oxidising micro-organisms in the sand thin coating in filters of drinking water purification and were found regularity and dependency of iron bacteria’s activities on the main technological parameters in removal of iron and manganese substances from the water.

Iron and manganese – the main components in Lithuanian groundwater, not following requirements of norms regulate the water quality. Now the most advanced method for removal of the mentioned substances is non-reagent technologies, where the important role is the on biological oxidation. This work includes experimental examination of the hypothesis, affirming that bacteria’s, oxidising iron and manganese can grow in some Lithuanian water treatment and can increase the removal of iron and manganese substances from the water. The novelty is that the method of identification and cultivation of iron bacteria’s presented in the foreign scientific publications was improved and adapted to research of such micro-organisms existing in the quartz sand filter media in the Lithuanian equipment of water treatment plant. For the first time in Lithuania there was examined quantitative distribution of iron and manganese oxidising micro-organisms in the sand thin coating in filters of drinking water purification and were found regularity and dependency of iron bacteria’s activities on the main technological parameters in removal of iron and manganese substances from the water.

Water supply systems aim, among other objectives, to protect public health by reducing the concentration of, and potentially eliminating, microorganisms pathogenic to human beings. Yet, because water supply systems are engineered systems facing variable conditions, such as raw water quality or treatment process performance, the quality of the drinking water produced also exhibits variability. The reliability of a treatment system is defined in this context as the probability of producing drinking water that complies with existing microbial quality standards. This thesis examines the concept of reliability for two physicochemical treatment technologies, conventional rapid granular filtration and ultrafiltration, used to remove the protozoan pathogen Cryptosporidium parvum from drinking water. First, fault tree analysis is used as a method of identifying technical hazards related to the operation of these two technologies and to propose ways of minimizing the probability of failure of the systems. This method is used to compile operators’ knowledge into a single logical diagram and allows the identification of important processes which require efficient monitoring and maintenance practices. Second, an existing quantitative microbial risk assessment model is extended to be used in a reliability analysis. The extended model is used to quantify the reliability of the ultrafiltration system, for which performance is based on full-scale operational data, and to compare it with the reliability of rapid granular filtration systems, for which performance is based on previously published data. This method allows for a sound comparison of the reliability of the two technologies. Several issues remain to be addressed regarding the approaches used to quantify the different input variables of the model. The approaches proposed herein can be applied to other water treatment technologies, to aid in prioritizing interventions to improve system reliability at the operational level, and to determine the data needs for further refinements of the estimates of important variables.

Pagrindinis geriamojo vandens šaltinis Lietuvoje – požeminis vanduo. Geros kokybės geriamasis vanduo yra svarbus veiksnys kiekvieno žmogaus gyvenime. Šio darbo tikslas – išanalizuoti Kelmės rajono vandenviečių tiekiamo geriamojo vandens kokybę ir jo tinkamumą vartoti 2004–2010 metais. Šiame darbe nagrinėjami Kelmės rajono vandenviečių tiekiamo geriamojo vandens toksiniai (cheminiai) (fluoridai, nitratai, nitritai), indikatoriniai (bendroji geležis, manganas, permanganato indeksas) ir mikrobiologiniai (kolonijas sudarantys vienetai, žarniniai enterokokai, žarninės lazdelės (E. coli)) kokybės rodikliai 2004–2010 m. laikotarpiu. Kai kurių analizuojamų vandenviečių vandens kokybė neatitinka normų dėl per didelio fluoridų bei bendrosios geležies kiekio. Nustatyta fluoridų koncentracija 2004–2010 metais DLK (DLK=1,5 mg/l) viršijo Gailių, Kelmės, Kukečių, Šedbarų ir Verpenos vandenvietėse. Bendrosios geležies koncentracija DLK (DLK=0,2) viršijo Budraičių, Gailių, Kukečių, Liolių, Maironių, Pagryžuvio, Šedbarų, Tytuvėnų vandenviečių vandenyje. Mangano koncentracija DLK (DLK=0,05 mg/l) viršijo tik Gailių vandenvietės vandenyje. Nitratų ir nitritų vidutinė koncentracija analizuojamu laikotarpiu DLK neviršija nei vienoje vandenvietėje. Analizuojamu 2004–2010 metų laikotarpiu vidutinės permanganato indekso vertės Kelmės rajono vandenvietėse DLK neviršijo (DLK=5 mg/l). Vandens kokybė Pagal mikrobiologinius rodiklius analizuojamose Kelmės rajono neatitiko reikalavimų pagal KSV... [toliau žr. visą tekstą] / The main source of drinking water in Lithuania is the groundwater. Quality of drinking water and harmful substances in drinking water is an important factor in everyone‘s life. The aim of this Diploma paper – to analyze quality of drinking water in watering–places in Kelmė district and its suitability for consumption in 2004–2010. In many watering–places of Kelmė district in drinking water was found to much fluoride and iron. Average concentration of fluoride in 2004–2010 exceeded MAC (Maximum Acceptable Concentration) in Gailiai, Kelmė, Kukečiai, Šedbarai and Verpena watering–places. Average concentration of iron exceeded MAC in Budraičiai, Gailiai, Kukečiai, Lioliai, Maironiai, Pagryžuvys, Šedbarai, Tytuvėnai watering–places. Average concentration of manganese in 2004 – 2010 exceeded MAC in Gailiai watering–place. Average concentration of organic matter (permanganate index), nitrate and nitrite did not exceeded MAC. In some watering–places was found temporary microbiological pollution. In water found colony–forming units. The survey in Kelmė district towns showed that most respondents water quality regarded as good. However, information about the quality of drinking water and its changes is inadequate. Sediments are the worst characteristic of drinking water in Kelmė district watering–places. Concentration of nitrate in Kelmė district wells in most cases exceeded MAC. In many wells of Kelmė district water was very hard (°d–>21) and hard (°d–>14).

A library of 18 coliform bacteria strains was obtained from different sampling points in the drinking water distribution system in Lexington, KY, over a three month period in 2006. To investigate the cause of the coliform occurrence we conducted a microbial source tracking study using phenotypic (API 20E, Biolog, and Vitek) and genotypic (pulsed field gel electrophoresis (PFGE) and ribotyping) analyses to determine the degree of genetic variation among isolates. Characterization of isolates by PFGE and ribotyping showed that coliform events in the distribution system were related and a regrowth problem may exist due to biofilm formation. The ability of a persistent Enterobacter cloacae strain to adhere and form biofilm was found to depend on environmental conditions such as temperature, pipe material, soiled surface, chlorine and nutrient levels with higher temperatures and nutrient levels promoting adherence. Considerable variation in adherence and biofilm formation was observed among representative Enterobacter isolates.

Research has shown biological filtration can be a successful treatment for manganese (Mn) removal from groundwater and surface water. In this study, bench-scale direct biofiltration was used to remove Mn and dissolved organic carbon (DOC) from a pH 6 surface water source in Halifax, Canada. The removal of Mn in pH 6 surface water was significantly (? = 0.05) removed with 200-300 µg/L phosphorus (P), and 500 µg/L hydrogen peroxide (H2O2). DOC removal was significantly (? = 0.05) improved with granular activated carbon (GAC) media, P enhancement at 200-300 µg/L, and H2O2 enhancement at 500 µg/L. Mn was likely removed by biological oxidation and physical adsorption to biogenic Mn and iron (Fe) oxides. These results show direct biofiltration of surface water at pH 6 can remove Mn below the 50 µg/L aesthetic guideline from a Mn loading of over 1 mg/L. Further research is required to verify the microbial mechanism.

Wide health gaps exist between Canada’s Inuit population and their non-Indigenous counterparts in nearly all categories. Two basic public health protection principles in any community worldwide are access to safe drinking water and sanitary wastewater management. The purpose of this research was to explore the relationships between public health and municipal water and wastewater systems in Coral Harbour, Nunavut. Using a qualitative case study approach, I conducted 37 interviews with residents and key informants and thematically analyzed the data. Findings suggest that crowded households experiencing domestic water shortages may result in negative health consequences. As well, pre and early settlement water customs are influencing current public health risks thereby requiring special consideration by municipal planners. Given these findings, recommendations include increasing domestic water access, strengthening source water monitoring programs, and establishing intergovernmental public health policies that co-benefit water resource management agendas as well as other priority issues in Nunavut.

Natural organic matter (NOM) is present in all surface waters as a result of decaying vegetation, biological activity, and organic soil. Alternative NOM removal processes such as anion exchange resins (AERs) have shown NOM removals typically ranging between 50 to 90%, with up to 99% removal achieved in some cases. The first portion of this study evaluated the performance of two AERs; a conventional Type 1 AER and magnetic ion exchange resin (i.e. MIEX®) for NOM removal from surface water quantified by UV254, dissolved organic carbon (DOC), and specific UV absorbance (SUVA). Samples were also characterized for chloride, sulphate, and chloride-to-sulphate mass ratio (CSMR) to provide additional information on water quality characteristics of AER treated waters. Overall, the results showed that both AERS were effective for removing NOM. However, the MIEX® resin provided greater removal of NOM with shorter contact times compared to the conventional resin investigated. Water treated with MIEX® resin showed significantly higher chloride and lower sulphate concentrations than the conventional AER. Higher CSMR values were found with MIEX® treated water compared to conventional AER system, although both resins showed CSMR much greater than 0.5, which can increase galvanic corrosion effects with lead. Bench-scale jar tests were conducted to investigate the impact of temperature on the efficacy of three NOM removal treatment technologies; enhanced coagulation with alum, MIEX® and a combined MIEX® treatment followed by coagulation with a low dose of alum. Higher settled water turbidity was observed during cold water operating conditions for all three processes. At cold-water operating conditions, DOC removal was reduced with combined MIEX® -Alum treatment, and UV254 removal was impacted for both MIEX® and MIEX® -Alum processes. The combined MIEX®-Alum process was found to provide the lowest THMFP and HAAFP at both temperatures to concentrations lower than current regulatory maximum acceptable concentration (MAC) guidelines in Canada. Surface charge analysis experiments were performed at bench-scale using synthetic water containing humic acid to determine the relationship between NOM and the charge of AER-treated waters. Further bench and pilot-scale studies were performed to investigate the use of surface charge measurements to monitor and optimize NOM removal during treatment with AER systems. Strong correlations were observed between UV254 and respective charge measurements (i.e. ZP, SC) of AER-treated synthetic and raw waters. The results of this research has shown that it is possible to use charge to optimize the MIEX® process for NOM removal. Additionally, it was found that SC measurements could be used as an operational tool for AER processes, where deviations in SC from optimum treatment would indicate the requirement for fresh resin addition or resin regeneration.

The ability of six types of granular activated carbon (GAC) to quench H2O2 was evaluated by bench-scale H2O2 decomposition kinetics tests and pilot-scale H2O2 breakthrough tests. Bench-scale studies showed that carbon ageing significantly reduced the performance of H2O2 quenching by the GAC, but that the greatest impacts occurred within the first 25 000 bed volumes of water treated, with performance tending to stabilize afterwards. Pilot-scale studies suggested that both H2O2 exposure and exposure to natural organic matter were important factors in GAC ageing, with exposure to oxygen also suspected of being important. A continuously stirred tank reactor (CSTR)-in-series model was proposed for the prediction of H2O2 breakthrough in a GAC column.