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Knowledge engagement in collaborative water governance: A New Brunswick exampleVanTol, Katherine January 2012 (has links)
Authoritative, top-down forms of environmental governance are presently giving way to more collaborative approaches in which decision making is an ongoing negotiation between government and non-government actors. There is growing consensus that critical environmental concerns—such as contamination of drinking water—relate as much to political, economic and social issues, as to technical and scientific issues. As the trend toward collaborative environmental governance continues, and as science-based knowledge increasingly shares a role in decision-making processes with more “local”, non-scientific knowledge, questions arise concerning how diverse knowledge contributions are understood and engaged in these governance processes. This research explored the relationships between knowledge and collaborative environmental governance processes. The purpose of the research was to identify (1) types of knowledge that individual actors bring into collaborative governance pertaining to water resource protection, (2) uses of that knowledge, and (3) features of collaborative processes that affect the engagement of actor knowledge. Collaborative water governance in New Brunswick provided the context for the research. Most actors did not see a definitive distinction between “expert”, scientific and “local”, non-scientific knowledge; they considered both to be important contributions. Nonetheless, science-based knowledge, especially natural science, was found to be a predominant knowledge type among actors involved in collaborative water governance. Science-based, expert knowledge was more readily used than local knowledge types in the various stages of collaborative governance. Leadership and the definition of actor roles were considered paramount for engaging a wide range of knowledge types in collaborative governance processes.
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Source Water Protection Planning in Metropolitan Canada2015 June 1900 (has links)
Source Water Protection (SWP) is recognized as the first barrier in the multi-barrier approach to reduce the risk of drinking water contamination. In Canada, provincial water agencies and municipalities lead most of the water management responsibility based on provincial regulations. However, SWP planning and implementation is variable across jurisdictions and influenced by different factors related to local capacity. Much of the water resources literature is focused on capacity-building limitations faced by small and rural water system operators. The purpose of this research is to investigate capacity-building limitations faced by metropolitan water system operators. Information from a questionnaire and document review in four selected Canadian metropolitan areas was gathered and analysed in this study. The results of this study show variability of SWP planning uptake as well as variability in approach toward SWP implementation. While large metropolitan areas may appear to possess ready access to financial capital, technical capability, and other forms of capacity to undertake SWP, the results of this research indicate the opposite. Metropolitan areas in Canada remain reliant on advanced water treatment and other engineering solutions to provide safe drinking water as opposed to SWP planning that invests in preventative measures through land use planning mechanisms. The results of this research contribute to the knowledge and understanding of SWP particularly as applied to metropolitan Canada.
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Molecular-Based Methods to Detect Viable Bacterial Pathogens in Source WatersBanihashemi Jahromi, Avid January 2013 (has links)
Humans can be exposed to waterborne bacterial pathogens and numerous outbreaks have been reported involving these microorganisms around the world. Many different enteric pathogens can be found in source waters used for drinking water. Assessing these pathogens and their possible threat to public health has always been important. Waterborne pathogens can be difficult to detect, and despite a large variety of recognized microbial detection techniques, the cause of many outbreaks has not been unidentified. Effective and rapid pathogen detection techniques are required to achieve reliable data for microbial source water quality, outbreak investigations, and for drinking water treatment efficacy monitoring.
Bacteria have long been detected using classical culture-based methods, with the rationale that living cells are able to grow/replicate. However, many pathogenic bacteria in source waters may turn into viable but not culturable (VBNC) cells and are thus undetectable by growth-based methodologies. Alternatively, PCR-based techniques have been developed to detect both non-culturable and culturable bacteria. Yet with these techniques, post-death DNA persistency can inaccurately overestimate the number of viable cells. This problem may be circumvented by an alteration to the PCR procedure that is reported to be able to block PCR amplification of DNA that originates from dead cells. This alteration involves a chemical pre-treatment step prior to PCR using a photoreactive intercalating dye, propidium monoazide (PMA).
In this research, a successful modification was made to the PMA-PCR method that can result in substantial suppression of the PCR signal from dead cells, and provide results that can more accurately measure bacterial pathogen viability. PMA-PCR was applied to high concentrations (1 × 107 cells mL-1) of heat-killed cells of Salmonella enterica and Campylobacter jejuni. Using PMA-PCR in combination with primers that amplified a relatively short fragment of the S. enterica invA gene (119 bp), only a 3-log reduction of the dead cell PCR signal was obtained. Similarly, for C. jejuni using PCR primers that amplified a relatively short fragment of DNA (174 bp of cpn60 gene), only a 1-log reduction of the PCR signal was observed for dead cells. Therefore, PMA treatment followed by PCR amplification of short DNA fragments resulted in incomplete signal inhibition of heat killed Salmonella and Campylobacter. To further investigate how PCR conditions can affect the ability of PMA to inhibit PCR amplification, primers were then used that could amplify a larger fragment of DNA. PCR amplification of a longer DNA fragment (1614 bp of invA gene for S. enterica and 1512 bp of cpn60 gene for C. jejuni) strongly suppressed the signal (7 log reduction) for both heat-killed Salmonella and Campylobacter. For UV-treated S. enterica and C. jejuni, short amplicon PMA-PCR showed no or very low PCR signal reduction, in part due to intact membranes directly after UV irradiation. Long amplicon qPCR, however, resulted in dead cell signal removal and PMA pretreatment had no effect on PCR signal suppression.
This study used quantitative PCR and the PMA-PCR viability assays to evaluate the levels and occurrences of four groups of pathogenic bacteria in surface water samples from two locations on the Grand River, Ontario, Canada, to demonstrate the reliability of the PMA-PCR technique for the enumeration of viable cells. The bacterial groups investigated included S. enterica, thermophilic Campylobacter, Escherichia coli O157:H7, and Arcobacter butzleri. Small numbers of dead cells (not more than 0.5 log 100 mL-1) were present, detected as the difference between PMA-PCR and PCR without PMA treatment. In this particular river, pathogen enumeration by PCR was only slightly influenced by false positive signal detection due to the presence of dead cells or extracellular DNA and reliable bacterial pathogen detection could be attained by PCR without PMA pretreatment. Viable A. butzleri were detected at elevated concentrations (up to 4.8 log cells per 100 mL) in the Grand River. Arcobacter has not been previously studied in the Grand River and this is one of the few studies that have quantitatively assessed Arcobacter in the environment. This suggests that additional research is required on the pathogenicity of this organism and its occurrence in water.
In the next stage of this research, both the improved viability assay (long amplicon PMA-PCR) and conventional quantitative PCR were applied to investigate the survival trends of selected enteric bacterial pathogens including Yersinia enterocolitica, S. enterica, C. jejuni, and A. butzleri. The target bacteria were inoculated into sterile or non-sterile river water to study the impact of background microbiota on cell survival. These experiments were perfomed at 3 different temperatures (5, 15, and 25°C) and at high/low dissolved oxygen (DO) concentrations (for C. jejuni, and A. butzleri only) to evaluate the effect of these potential environmental stresses on bacterial survival trends. The results indicated that the autochthonous microbiota in river water had a significant effect on the bacterial die-off. Although lower temperatures enhanced bacterial survival in non-sterile river water, it was found that PCR may overestimate the effect of temperature on survival and that the PCR viability assays (PMA-PCR) could more accurately measure the impact of temperature. The survival of viable C. jejuni was adversely affected by high DO levels only at a low temperature (5°C) and this effect was observed only when the PMA-PCR viability assay was applied. A. butzleri survival was not affected by water DO levels.
This research provides an improved understanding of viable/active enteric waterborne bacteria and their survival in the aquatic microcosms as well as reliable data to better elucidate the effect of environmental factors on the occurrence of pathogenic bacteria. It can also offer valuable information for microbial risk assessments used by regulators and decision makers.
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Assessing the Role of Phosphorus as a Source Water and Treatment Vulnerability Indicator: Implications for Planning, Management and OperationsChik, Ho Shing (Alex) January 2013 (has links)
Source water protection (SWP) refers to the pressing global need to address the combination of issues affecting water supply and treatment: water quality, water quantity and timing of availability. Although SWP has been increasingly advocated by drinking water professionals, tools to relate upstream land-use impacts to downstream water treatability are lacking. Treatment water quality metrics can seldom be used to decouple the cumulative water quality impacts of natural and anthropogenic land-use disturbances; moreover, some changes in source water quality that potentially compromise the effectiveness of treatment are not reflected by changes in magnitude of these treatment water quality metrics. This underscores the need for an effective vulnerability indicator: a metric for monitoring and assessing the susceptibility of a system to harm arising from source water quality changes. In this research, a proof-of-concept approach was used to evaluate phosphorus as an indicator for linking source water and treatment vulnerabilities in a forested watershed in Alberta, Canada.
Relationships between phosphorus and various water quality parameters were assessed using historical Elbow River discharge and Glenmore Reservoir water quality data from 2000 to 2010 to elucidate source water vulnerabilities. The results showed that allochthonous inputs from the Elbow River were the primary drivers of source water quality in the reservoir during significant hydrological events. Autochthonous processes such as dilution and deposition of allochthonous inputs in reservoir bottom sediments buffered water quality changes within the reservoir. Carbon:nitrogen:phosphorus (C:N:P) nutrient ratios observed in the reservoir were indicative of severe-to-moderate phosphorus-limitation for primary production. Although total phosphorus (TP) concentrations reached threshold levels for supporting mesotrophic to eutrophic conditions, primary production was limited. Consistently low reservoir chlorophyll-a levels and low dissolved phosphorus concentrations suggest that drinking water treatment impacts are unlikely to be confounded by the presence of algal matter.
The impacts of source water quality changes to drinking water treatability were inferred using historical source water quality data and treatment performance metrics at the Glenmore Water Treatment Plant (WTP) using forward-stepwise multiple linear regression. Raw water TP and total organic carbon (TOC) concentrations explained 78.8% of the coagulant dose variation used in coagulation and flocculation processes (n = 22). Additional plant water quality data and treatment performance metrics were collected in 2012 to confirm these observations. Plant raw water UV-absorbance at 254 nm (UVA254) and TP concentrations described 98.3% of the alum coagulant dose variation used in the newly-installed Actiflo© ballasted-sand flocculation process (n = 26). SUVA and TP together explained 91.2% of the polymer dose variation (n = 26). The inclusion of TP as a significant predictor of coagulant and polymer doses, coupled with a review of literature, suggest that TP is a more sensitive indicator of waterborne particle concentrations present in the raw water than turbidity. Accordingly, TP may play a role in the critical drinking water treatment processes of coagulation, flocculation and clarification which has direct implications for process optimization, chemical coagulant costs, sludge production and impacts to subsequent treatment processes.
Scenario building based on anticipated land-uses and impacts from catastrophic landscape disturbances using the coagulant regression models was used to explicitly link potential source water quality impacts to drinking water treatability. The innovative approach of estimating land-use TP loading, steady state reservoir TP concentrations and coagulant dosing requirements at the WTP provides a framework that enables the development and coordination of land-use planning, reservoir management and drinking water treatment operations strategies respectively. Total phosphorus provides a common vulnerability metric relevant to both land-use and water managers for developing and assessing integrated land-use management and SWP strategies.
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Validation of a Canadian drinking source water quality index and its application to investigate the spatial scale of land use – source water quality relationshipsHurley, Tim 13 April 2012 (has links)
Source water protection is a key component of the multiple barrier approach to drinking water. The management of contamination within source water ecosystems is associated with many benefits but also several challenges. By its very nature, source water protection is site specific and requires the cooperation of numerous watershed stakeholders to ensure sufficient financial resources and social will. This work focused on two critical aspects of source water protection:
1) The facilitation of effective communication to promote cooperation among watershed stakeholders and aid in public education programs.
A drinking source water quality index presents a potential communication and analysis tool to facilitate cooperation between diverse interest groups as well as represent composite source water quality. I tested the effectiveness of the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) in capturing expert assessments of surface drinking source water quality. In cooperation with a panel of drinking water quality experts I identified a core set of parameters to reflect common Canadian surface source water concerns. Based upon existing source water guidelines, drinking source water target values were drafted for use in the index corresponding to two basic treatment levels. Index scores calculated using the core parameter set and associated source water target values were strongly correlated with expert assessments of source water quality. Amended with a modified index calculation procedure to accommodate parameters measured at different frequencies within any particular study period, the CCME WQI provides a valuable means of monitoring, communicating, and understanding surface source water quality.
2) The application of source water protection strategies to the appropriate spatial scale in order to manage contaminants of concern in a cost effective manner.
Using data gathered from 40 Canadian rivers across 4 western Canadian ecozones I examined the spatial scales at which landuse was most closely associated with drinking source water quality metrics. Linear mixed effects models revealed that different spatial areas of landuse influence drinking source water quality depending on the parameter and season investigated. Microbial risk, characterized using E. coli measures, was only associated with landuse at the local spatial scale. Turbidity measures exhibited a complex association with landuse suggesting that the landuse areas of greatest influence can range from the local to the watershed scale. Total organic carbon concentrations were only associated with landuse characterized at the entire watershed scale. The validated CCME WQI was used to provide a composite measure of seasonal drinking source water quality but did not provide additional information beyond the analyses of individual parameters. These results suggest that entire watershed management is required to safeguard drinking water sources with more focused efforts at targeted spatial scales to reduce identified risk parameters.
The source water protection tools and knowledge that I present have immediate application within Canada. Practitioners must be aware of the limitations of the CCME WQI however it provides a validated means of communicating complex source water quality information to non-specialized end users. Combined with the scale dependency of landuse-source water relationships that I elucidated, water quality managers can target contaminant reduction strategies in a more cost-effective manner and relay water quality status and trends to concerned groups. / Graduate
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Source Water Quality Assessment and Source Water Characterization for Drinking Water ProtectionWang, Yuxin 01 September 2014 (has links)
Source water quality plays a critical role in maintaining the quality and supply of drinking water, yet it can be negatively affected by human activities. In Pennsylvania, coal mining and treatment of conventional oil and gas drilling produced wastewaters have affected source water quality for over 100 years. The recent unconventional natural gas development in the Marcellus Shale formation produces significant volumes of wastewater containing bromide and has the potential to affect source water quality and downstream drinking water quality. Wastewater from coal-fired power plants also contains bromide that may be released into source water. Increasing source water bromide presents a challenge as even small amounts of bromide in source water can lead to carcinogenic disinfection by-products (DBPs) in chlorinated finished drinking water. However, bromide is not regulated in source water and is not removed by conventional drinking water treatment processes. The objective of this work is to evaluate the safe bromide concentration in source water to minimize the cancer risk of trihalomethanes - a group of DBPs - in treated drinking water. By evaluating three years of water sampling data from the Monongahela River in Southwestern Pennsylvania, the present analysis reached three conclusions. First, bromide monitoring for source water quality should be taken at drinking water intake points. Water sample types (river water samples vs drinking water intake samples) can lead to different water quality conclusions and thus affect regulatory compliance decision-making. Second, bromide monitoring at drinking water intake points can serve as a predictor for changes in heavily brominated trihalomethanes concentrations in finished water. Increasing bromide in source water can serve as an early warning sign of increasing formation of heavily brominated trihalomethanes and their associated cancer risks in drinking water. Finally, this work developed a statistical simulation model to evaluate the effect of source water bromide on trihalomethane formation and speciation and to analyze the changing cancer risks in water associated with these changing bromide concentrations in the Monongahela River. The statistical simulation method proposed in this work leads to the conclusion that the bromide concentration in source water must be very low to prevent the adverse health effects associated with brominated trihalomethanes in chlorinated drinking water. This method can be used by water utilities to determine the bromide concentration in their source water that might indicate a need for process changes or by regulatory agencies to evaluate source water bromide issues.
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Knowledge engagement in collaborative water governance: A New Brunswick exampleVanTol, Katherine January 2012 (has links)
Authoritative, top-down forms of environmental governance are presently giving way to more collaborative approaches in which decision making is an ongoing negotiation between government and non-government actors. There is growing consensus that critical environmental concerns—such as contamination of drinking water—relate as much to political, economic and social issues, as to technical and scientific issues. As the trend toward collaborative environmental governance continues, and as science-based knowledge increasingly shares a role in decision-making processes with more “local”, non-scientific knowledge, questions arise concerning how diverse knowledge contributions are understood and engaged in these governance processes. This research explored the relationships between knowledge and collaborative environmental governance processes. The purpose of the research was to identify (1) types of knowledge that individual actors bring into collaborative governance pertaining to water resource protection, (2) uses of that knowledge, and (3) features of collaborative processes that affect the engagement of actor knowledge. Collaborative water governance in New Brunswick provided the context for the research. Most actors did not see a definitive distinction between “expert”, scientific and “local”, non-scientific knowledge; they considered both to be important contributions. Nonetheless, science-based knowledge, especially natural science, was found to be a predominant knowledge type among actors involved in collaborative water governance. Science-based, expert knowledge was more readily used than local knowledge types in the various stages of collaborative governance. Leadership and the definition of actor roles were considered paramount for engaging a wide range of knowledge types in collaborative governance processes.
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Source Water Protection Planning in Ohio: Assessing the Integration of Land Use Planning and Water Management for Safe and Sustainable Public Drinking Water SourcesWilson, Jessica P. 06 November 2020 (has links)
No description available.
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Quantitative assessment of exposure to enteric pathogens in drinking waterMahajan, Rishab January 2009 (has links)
No description available.
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Impact of Surrounding Land Uses on Surface Water QualityElbag Jr., Mark A. 03 May 2006 (has links)
Source water protection is important to maintain public health by keeping harmful pathogens out of drinking water. Non-point source pollution is often times a major contributor of pollution to surface waters, and this form of pollution can be difficult to quantify. This study examined physical, chemical, and microbiological water quality parameters that may indicate pollution and may help to identify sources of pollution. These included measures of organic matter, particles, and indicator organisms (fecal coliforms and E. coli). The parameters were quantified in the West Boylston Brook, which serves as a tributary to the Wachusett Reservoir and is part of the drinking water supply for the Metropolitan Boston area. Water quality was determined over four seasons at seven locations in the brook that were selected to isolate specific land uses. The water quality parameters were first analyzed for trends by site and by season. Then, a correlation analysis was performed to determine relationships among the water quality parameters. Lastly, ANOVA analyses were used to determine statistically significant variations in water quality along the tributary.
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