<p>In the U.S, more than 5.6 million commercial buildings are in operation and some include offices, schools, and childcare centers. These large buildings have complex indoor plumbing and often drinking water chemical and microbiological safety hazards can go undocumented. Generally, the larger the building’s square footage, the greater number of building occupants potentially exposed to the drinking water and greater amount and complexity of indoor cold and hot water piping and appurtenances. Because commercial buildings routinely undergo periods of low to no water use (e.g., holidays, weekends) cold and hot water can stagnate in the plumbing. This stagnation can allow for chemical and biological drinking water quality safety to deteriorate. This thesis work was designed to examine water safety challenges in school, childcare center, and office buildings to address existing knowledge-gaps.<br></p><p><br></p><p>The study described in Chapter 1 was conducted to better understand the risks of elevated copper levels at U.S. schools and childcare centers. Study goals were to: (1) understand occurrences of copper in school and childcare center drinking water systems, (2) review acute and chronic health impacts associated with the ingestion of copper contaminated water, and (3) examine the effectiveness of remedial actions to address copper in drinking water. Of the more than 130,000 schools and 856,000 childcare centers in the U.S., only about 1.7% of all those facilities had copper drinking water testing data recorded in a federal Safe Drinking Water database since the database was created in 1992. Of these facilities that were designated public water systems, about 13% (2,332) had reported a copper drinking water exceedance. Over a period of 30 years, very few studies have been conducted to document copper levels in schools and childcare centers. Available studies reported widely different sampling protocols and remedial actions. Flushing copper contaminated water from plumbing was the most evaluated remedial action, but flushing sometimes needed to be repeated indefinitely because copper exceeded safe limits within hours after flushing stopped. In-building water treatment with ion exchange systems and orthophosphate corrosion inhibitor addition have been used. At present, there is limited data from testing for copper in schools and childcare centers as well as studies to aid building managers in identifying and remediating copper occurrences. <br></p><p><br></p><p>The study described in Chapter 2 was designed to better understand chemical and microbiological quality in a green office building due to weekend stagnation events (~60 hours per event). Specific goals were (1) to investigate characterize disinfectant, pH, as well as heavy metal and microbial contaminant levels at the building point-of-entry and fixtures throughout the building, (2) understand how water quality varied spatially and by fixture use frequency, and (3) investigate the effectiveness of remedial actions on removing the water quality problems identified. As-built plumbing drawings were used to create a sampling plan and flushing plan. The total chlorine concentration decreased during stagnation (p < 0.05) and was highest at the building entry point (max 0.8 mg/L), and lower throughout the building (max 0.28 mg/L). Total cell counts were greater on Mondays compared to Fridays (p < 0.05). Legionella spp. was highest at the fixture with zero water use recorded during the study. Copper and lead levels throughout the building increase over the weekend (p < 0.05). Copper exceeded the U.S. federal health-based drinking water limit (1.3 mg/L) at 4 of the 12 tested locations. These locations all branched off the same riser. Manual fixture flushing temporarily reduced copper levels, but copper rebounded quickly prompting the need to flush fixtures every 19 hours. Results showed that drinking water testing should be required for building water systems before occupancy permits are issued, and after an extended stagnation period to understand worst case conditions. Testing should include disinfectant level, copper, lead, and legionella. <br></p><p><br></p><p>This thesis research found that a general lack of water testing data for existing office, school, and childcare center buildings inhibited a wider understanding of water safety risks. It is recommended that building officials adopt water testing as a requirement for building occupancy certificates. Testing should also be conducted periodically during the life of the buildings especially after unusually long stagnation periods (e.g., shutdowns or holiday breaks), and in buildings where children or other sensitive populations (e.g., elderly or people with underlying conditions) are occupants. Testing should include disinfectant level, copper, lead, and legionella at the point of entry and multiple locations throughout the building, depending on fixture use and building occupants. Without water testing, occupants may continue to be exposed to water that does not meet federal safe drinking water limits and go undetected. If contamination is found, building managers should review the flushing plan and potentially consider point of use water treatment to address short- and long-term water safety problems. <br></p>

Yes / Water is essential in everyday life hence, there is a need for it to be available in quality and quantity to all. This study aimed to review relevant published studies on water accessibility and safety in Ghana from 2015 to 2022 to determine the plausibility of Ghana achieving Sustainable Development Goal 6.1 by 2030. METHODOLOGY A systematic review was conducted based on the PRISMA guidelines using four databases including ProQuest, Science Direct, Web of Science and Scopus. Studies with data on specified keywords and published in English from January 2015 to June 2022 were included in this study. Duplicated titles were removed and the title, and full text of remained studies were reviewed by two independent coders. Thematic analysis was conducted to identify themes. RESULTS Ten studies met the criteria and the majority of them used qualitative design (60%). Five main themes were identified including; causes of water contamination, the prevalence of waterborne diseases, types of water sources, implemented policies and challenges for policy implementation. The government implemented policies to provide safe and potable drinking water for the citizen and now, about 72% of the population have access to treated pipe water. Some challenges facing implemented policies include political interest in illegal mining, inadequate waste disposal facilities, and poverty. CONCLUSION This study shows that Ghana can achieve Sustainable Development Goal 6.1 which is "Access to clean and affordable water for all" by 2030. The government, public health organizations and stakeholders should work together to alleviate the challenges faced in achieving this goal.

There is enough freshwater on the planet to ensure clean and accessible water for every human being. Despite this fact, water scarcity is a global problem affecting the livelihoods of people everywhere. This paradox can be seen in India. The country has a vast source of water through their many rivers and lakes. Nevertheless, it battles with issues regarding water scarcity and sanitation. Groundwater and rivers are polluted to a high extent and known contaminators are both human waste and industrial effluents. In Mandideep municipality, located in Madhya Pradesh, India, industrial effluents and sewage waste is dumped into the Betwa river which is heavily polluted as a result. These premises lay the foundation for this minor field study whichlooks at women’s wellbeing and capabilities through the lens of ecofeminism and the sustainable livelihood approach. Four villages, in close proximity to the river, are subject of investigation with the aim to understand the female perception of the Betwa river and whetherthe water quality impacts women’s livelihood strategies or not. During the field study, 21 women in these villages have been interviewed. The study concludes that the women’spossibilities are directly connected to environmental wellbeing where the continued undermining of natural resources reduces their capability to obtain sustainable livelihoods. The level of interaction with the river depends on the geographic position of the villages and its proximity to industrial belt of Mandideep.

Submitted by Bento De Godoy Neto (aguasdegoias@gmail.com) on 2018-10-26T19:11:14Z No. of bitstreams: 1 revisado_FINAL POS DEFESA BENTO GODOY_BEGONE (1) - CORRIGIDO FINAL (1).docx: 17783786 bytes, checksum: cd8b5863512304d493fc3b36f6979fa1 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-10-26T19:51:58Z (GMT) No. of bitstreams: 1 godoyneto_b_me_ilha.pdf: 8080883 bytes, checksum: 934081386e465a381961e2ab601d8c6d (MD5) / Made available in DSpace on 2018-10-26T19:51:58Z (GMT). No. of bitstreams: 1 godoyneto_b_me_ilha.pdf: 8080883 bytes, checksum: 934081386e465a381961e2ab601d8c6d (MD5) Previous issue date: 2018-08-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A abordagem sobre a segurança hídrica diz respeito ao conhecimento dos aspectos ambientais da bacia hidrográfica, os usos atuais e tendências dos recursos naturais, considerando a multiplicidade de usos da água. Consiste em considerar tanto o planejamento do uso e ocupação da terra, quanto dos recursos hídricos na sua integridade ambiental e social, e não somente de um ponto de vista econômico, visando à segurança hídrica no abastecimento de água para a população local. Assim, neste trabalho propõe-se contribuir para a segurança hídrica do abastecimento público da população urbana de Caldas Novas, Goiás, Brasil. Nos procedimentos metodológicos, por meio de revisão bibliográfica pertinente e levantamentos de campo na bacia hidrográfica do Ribeirão Pirapetinga, especialmente dos aspectos ambientais e socioeconômicos impactantes na segurança hídrica municipal, realizou-se levantamento de dados relativos à história de Caldas Novas, ocupação territorial, ocorrência das águas termais, crescimento populacional, expansão da área urbana, caracterização da bacia hidrográfica quanto a aspectos de solo, clima, geomorfologia, uso do solo e ocupação da terra (entre 1995 e 2017), disponibilidade hídrica e vazão consumida pelos principais setores usuários da bacia hidrográfica: a irrigação e o abastecimento público. Dentre os resultados destacam-se a constatação da vulnerabilidade do atual sistema em atender à demanda de água na cidade, para a qual as ações de preservação de água tratada têm efeito paliativo frente ao crescimento da demanda, a alta susceptibilidade à ocorrência de secas pela realização de captação direta sem acumulação; a aferição do quadro de degradação ambiental na bacia hidrográfica (redução da vegetação nativa em quase 38%; aumento de solo exposto em aproximadamente 27%; déficit de área de Reserva Legal em torno de 20%), além da ocorrência de expansão urbana na bacia hidrográfica a montante da captação. Os dados de acumulações nas propriedades rurais na bacia hidrográfica evidenciam a preservação estimada em 5.150.000,00m³ em 205 barramentos, contribuindo para a regularização hídrica frente ao percentual de usos de 53% para o abastecimento público de Caldas Novas. As medidas sugeridas para a garantia da segurança hídrica relacionam-se à implantação de um consórcio intermunicipal, futura implantação de pagamento por serviços ambientais lastreado no turismo e utilização das alternativas de uso das águas termais no abastecimento público e construção de barramento no Ribeirão Pirapetinga. Espera-se que este trabalho contribua para subsidiar ações públicas voltadas para a gestão das águas do manancial que abastece Caldas Novas, garantindo-se sua segurança hídrica. / The water safety approach refers to understanding the environmental aspects of the hydrographic basin, as well as current and trend uses of natural resources, considering the plurality of uses. It means taking into account planning of land use and occupancy, as well as planning of water resources on their environmental and social entirety, and not only from an economic point of view, thus aiming the improvement of local population life quality. The proposition of this work is contributing to the water safety of urban population public supply in Caldas Novas, Goiás, Brazil. Through a relevant bibliographic review and field surveys in the Pirapetinga Stream Basin, especially regarding environmental and socioeconomic aspects impacting on local water safety, data were collected on the history of Caldas Novas, its territorial occupation, occurrence of thermal waters, population growth, expansion of the urban area, characterization of the hydrographic basin regarding aspects of soil, climate, geomorphology, land use and land occupancy (between 1995 and 2017), as well as water availability and water flow rate consumed by the main users of the basin: irrigation and public supply. One verified the current system vulnerability in meeting the city demand for water, to which the actions of reserving treated water have only a palliative effect, against the increasing demand. One observed the high susceptibility to drought occurrence due to direct catchment without accumulation. A situation of environmental degradation was observed in the hydrographic basin (a decrease around 38% in native vegetation; an increase of approximately 27% in soil exposure; a shortfall close to 20% in the Legal Reserve Area), besides the occurrence of urban expansion in the hydrographic basin upstream of the catchment area. Data on the accumulation in the hydrographic basin show the reserve estimated in 5.150.000,00 m3 in 205 dams, contributing to water regularization against the usage rate of 53% for public supply in Caldas Novas. Suggested measures for assuring water safety are related to the implementation of a consortium among municipalities, future implementation of payment for environmental services backed by tourism, as well as the adoption of alternatives for the use of thermal waters in the public supply and construction of dams in the Pirapetinga Stream. it is expected that this paper contributes to subsidize public actions directed to the management of the waters of the source that supplies Caldas Novas, guaranteeing its water security. / CAPES: Código de Financiamento 001

Safe drinking water is a basic need; and risk assessment tools may assist in prioritizing actions to improve water safety. The objective of this research was to determine the appropriateness of current risk assessment approaches for First Nations drinking water systems. Criteria to evaluate risk assessment approaches were developed by combining common elements from literature, key informant interviews, and surveys. The criteria were compared against selected tools for drinking water risk assessment, including tools developed by Australia, Montana, Indian and Northern Affairs, and the University of Guelph. None of the tools, as available, met all of the criteria. Important considerations were found to include the operator, monitoring and recordkeeping, maintenance, technical considerations, emergency response plans, and source water protection. The tools were generally weak in assessing some potential challenges facing small, remote, and First Nations communities; including financial constraints, and taking a holistic view of water. / Note: this thesis was also submitted in hard-copy to Graduate Services

Orientador: Cláudio Antônio Di Mauro / Resumo: A abordagem sobre a segurança hídrica diz respeito ao conhecimento dos aspectos ambientais da bacia hidrográfica, os usos atuais e tendências dos recursos naturais, considerando a multiplicidade de usos da água. Consiste em considerar tanto o planejamento do uso e ocupação da terra, quanto dos recursos hídricos na sua integridade ambiental e social, e não somente de um ponto de vista econômico, visando à segurança hídrica no abastecimento de água para a população local. Assim, neste trabalho propõe-se contribuir para a segurança hídrica do abastecimento público da população urbana de Caldas Novas, Goiás, Brasil. Nos procedimentos metodológicos, por meio de revisão bibliográfica pertinente e levantamentos de campo na bacia hidrográfica do Ribeirão Pirapetinga, especialmente dos aspectos ambientais e socioeconômicos impactantes na segurança hídrica municipal, realizou-se levantamento de dados relativos à história de Caldas Novas, ocupação territorial, ocorrência das águas termais, crescimento populacional, expansão da área urbana, caracterização da bacia hidrográfica quanto a aspectos de solo, clima, geomorfologia, uso do solo e ocupação da terra (entre 1995 e 2017), disponibilidade hídrica e vazão consumida pelos principais setores usuários da bacia hidrográfica: a irrigação e o abastecimento público. Dentre os resultados destacam-se a constatação da vulnerabilidade do atual sistema em atender à demanda de água na cidade, para a qual as ações de preservação de água tratada têm... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The water safety approach refers to understanding the environmental aspects of the hydrographic basin, as well as current and trend uses of natural resources, considering the plurality of uses. It means taking into account planning of land use and occupancy, as well as planning of water resources on their environmental and social entirety, and not only from an economic point of view, thus aiming the improvement of local population life quality. The proposition of this work is contributing to the water safety of urban population public supply in Caldas Novas, Goiás, Brazil. Through a relevant bibliographic review and field surveys in the Pirapetinga Stream Basin, especially regarding environmental and socioeconomic aspects impacting on local water safety, data were collected on the history of Caldas Novas, its territorial occupation, occurrence of thermal waters, population growth, expansion of the urban area, characterization of the hydrographic basin regarding aspects of soil, climate, geomorphology, land use and land occupancy (between 1995 and 2017), as well as water availability and water flow rate consumed by the main users of the basin: irrigation and public supply. One verified the current system vulnerability in meeting the city demand for water, to which the actions of reserving treated water have only a palliative effect, against the increasing demand. One observed the high susceptibility to drought occurrence due to direct catchment without accumulation. A situatio... (Complete abstract click electronic access below) / Mestre

Emergency preparedness steps taken by individuals in Utah households were evaluated in 3 studies. Study 1 evaluated the 2011 landline and cell phone Behavioral Risk Factor Surveillance System Survey and General Preparedness Optional Module results from two states, Louisiana and Utah, to find factors from demographic and medical data that can be used to predict emergency preparedness in individuals. Stepwise logistical regression analysis ascertained the ability of chosen variables to predict individuals' preparedness. The rate of prepared individuals was lower if they were between the ages of 18 to 54 years, when compared to the reference age group of 65 or older. Also, the rate of prepared participants was lower if they were female, had children under age 18 at home, or were unable to afford a doctor in the past year. Rate of prepared respondents was higher if they owned a home or were married (p <0.05). Study 2 evaluated water stored for emergency purposes in households throughout Utah for coliform, E. coli, free chlorine, and antimony. Ninety one percent of the stored water samples were found to be safe for human consumption. However, 9% of water samples were not considered safe due to over chlorination or the presence of coliform. Of 240 samples, 7 contained coliform and 14 samples had total chlorine levels over the Environmental Protection Agency's 4 ppm limit. Water in clear, polyethylene terephthalate soda bottles, even when stored for >18 months, did not exceed 0.3 ppb antimony, a level significantly lower than the Environmental Protection Agency limit of 6.0 ppb antimony. Study 3 measured for one year the temperature and humidity of food storage areas in 67 households within Utah. In 63% of locations, temperatures exceeded 24 °C, which can be considered abusive for food storage. The maximum temperature reached in a food storage area was 37.9 °C. Percent relative humidity exceeded 60% in 43% of food storage areas, which can be considered abusive for food stored in packaging permeable to moisture. The maximum percent relative humidity reached was 92.5%. In conclusion, most water stored for emergency purposes was considered safe, but temperature and humidity conditions for most food storage areas exceeded recommended maximums, and emergency preparedness of households within Utah needs to be improved.

Algae and cyanobacteria occur naturally in source waters and are known to cause extensive problems in the drinking water treatment industry. Cyanobacteria (especially Anabaena sp. and Microcystis sp.) are responsible for many water treatment problems in drinking water treatment works (DWTW) all over the world because of their ability to produce organic compounds like cyanotoxins (e.g. microcystin) and taste and odour compounds (e.g. geosmin) that can have an adverse effect on consumer health and consumer confidence in tap water. Therefore, the monitoring of cyanobacteria in source waters entering DWTW has become an essential part of drinking water treatment management. Managers of DWTW, rely heavily on results of physical, chemical and biological water quality analyses, for their management decisions. But results of water quality analyses can be delayed from 3 hours to a few days depending on a magnitude of factors such as: sampling, distance and accessibility to laboratory, laboratory sample turn-around times, specific methods used in analyses etc. Therefore the use of on-line (in situ) instruments that can supply real-time results by the click of a button has become very popular in the past few years. On-line instruments were developed for analyses like pH, conductivity, nitrate, chlorophyll-a and cyanobacteria concentrations. Although, this real-time (on-line) data has given drinking water treatment managers a better opportunity to make sound management decisions around drinking water treatment options based on the latest possible results, it may still be “too little, too late” once a sudden cyanobacterial bloom of especially Anabaena sp. or Microcystis sp. enters the plant. Therefore the benefit for drinking water treatment management, of changing the focus from real-time results to future predictions of water quality has become apparent. The aims of this study were 1) to review the environmental variables associated with cyanobacterial blooms in the Vaal Dam, as to get background on the input variables that can be used in cyanobacterial-related forecasting models; 2) to apply rule-based Hybrid Evolutionary Algorithms (HEAs) to develop models using a) all applicable laboratory-generated data and b) on-line measureable data only, as input variables in prediction models for harmful algal blooms in the Vaal Dam; 3) to test these models with data that was not used to develop the models (so-called “unseen data”), including on-line (in situ) generated data; and 4) to incorporate selected models into two cyanobacterial incident management protocols which link to the Water Safety Plan (WSP) of a large DWTW (case study : Rand Water). During the current study physical, chemical and biological water quality data from 2000 to 2009, measured in the Vaal Dam and the 20km long canal supplying the Zuikerbosch DWTW of Rand Water, has been used to develop models for the prediction of Anabaena sp., Microcystis sp., the cyanotoxin microcystin and the taste and odour compound geosmin for different prediction or forecasting times in the source water. For the development and first stage of testing the models, 75% of the dataset was used to train the models and the remaining 25% of the dataset was used to test the models. Boot-strapping was used to determine which 75% of the dataset was to be used as the training dataset and which 25% as the testing dataset. Models were also tested with 2 to 3 years of so called “unseen data” (Vaal Dam 2010 – 2012) i.e. data not used at any stage during the model development. Fifty different models were developed for each set of “x input variables = 1 output variable” chosen beforehand. From the 50 models, the best model between the measured data and the predicted data was chosen. Sensitivity analyses were also performed on all input variables to determine the variables that have the largest impact on the result of the output. This study have shown that hybrid evolutionary algorithms can successfully be used to develop relatively accurate forecasting models, which can predict cyanobacterial cell concentrations (particularly Anabaena sp. and Microcystis sp.), as well as the cyanotoxin microcystin concentration in the Vaal Dam, for up to 21 days in advance (depending on the output variable and the model applied). The forecasting models that performed the best were those forecasting 7 days in advance (R2 = 0.86, 0.91 and 0.75 for Anabaena[7], Microcystis[7] and microcystin[7] respectively). Although no optimisation strategies were performed, the models developed during this study were generally more accurate than most models developed by other authors utilising the same concepts and even models optimised by hill climbing and/or differential evolution. It is speculated that including “initial cyanobacteria inoculum” as input variable (which is unique to this study), is most probably the reason for the better performing models. The results show that models developed from on-line (in situ) measureable data only, are almost as good as the models developed by using all possible input variables. The reason is most probably because “initial cyanobacteria inoculum” – the variable towards which the output result showed the greatest sensitivity – is included in these models. Generally models predicting Microcystis sp. in the Vaal Dam were more accurate than models predicting Anabaena sp. concentrations and models with a shorter prediction time (e.g. 7 days in advance) were statistically more accurate than models with longer prediction times (e.g. 14 or 21 days in advance). The multi-barrier approach in risk reduction, as promoted by the concept of water safety plans under the banner of the Blue Drop Certification Program, lends itself to the application of future predictions of water quality variables. In this study, prediction models of Anabaena sp., Microcystis sp. and microcystin concentrations 7 days in advance from the Vaal Dam, as well as geosmin concentration 7 days in advance from the canal were incorporated into the proposed incident management protocols. This was managed by adding an additional “Prediction Monitoring Level” to Rand Waters’ microcystin and taste and odour incident management protocols, to also include future predictions of cyanobacteria (Anabaena sp. and Microcystis sp.), microcystin and geosmin. The novelty of this study was the incorporation of future predictions into the water safety plan of a DWTW which has never been done before. This adds another barrier in the potential exposure of drinking water consumers to harmful and aesthetically unacceptable organic compounds produced by cyanobacteria. / PhD (Botany), North-West University, Potchefstroom Campus, 2015

Algae and cyanobacteria occur naturally in source waters and are known to cause extensive problems in the drinking water treatment industry. Cyanobacteria (especially Anabaena sp. and Microcystis sp.) are responsible for many water treatment problems in drinking water treatment works (DWTW) all over the world because of their ability to produce organic compounds like cyanotoxins (e.g. microcystin) and taste and odour compounds (e.g. geosmin) that can have an adverse effect on consumer health and consumer confidence in tap water. Therefore, the monitoring of cyanobacteria in source waters entering DWTW has become an essential part of drinking water treatment management. Managers of DWTW, rely heavily on results of physical, chemical and biological water quality analyses, for their management decisions. But results of water quality analyses can be delayed from 3 hours to a few days depending on a magnitude of factors such as: sampling, distance and accessibility to laboratory, laboratory sample turn-around times, specific methods used in analyses etc. Therefore the use of on-line (in situ) instruments that can supply real-time results by the click of a button has become very popular in the past few years. On-line instruments were developed for analyses like pH, conductivity, nitrate, chlorophyll-a and cyanobacteria concentrations. Although, this real-time (on-line) data has given drinking water treatment managers a better opportunity to make sound management decisions around drinking water treatment options based on the latest possible results, it may still be “too little, too late” once a sudden cyanobacterial bloom of especially Anabaena sp. or Microcystis sp. enters the plant. Therefore the benefit for drinking water treatment management, of changing the focus from real-time results to future predictions of water quality has become apparent. The aims of this study were 1) to review the environmental variables associated with cyanobacterial blooms in the Vaal Dam, as to get background on the input variables that can be used in cyanobacterial-related forecasting models; 2) to apply rule-based Hybrid Evolutionary Algorithms (HEAs) to develop models using a) all applicable laboratory-generated data and b) on-line measureable data only, as input variables in prediction models for harmful algal blooms in the Vaal Dam; 3) to test these models with data that was not used to develop the models (so-called “unseen data”), including on-line (in situ) generated data; and 4) to incorporate selected models into two cyanobacterial incident management protocols which link to the Water Safety Plan (WSP) of a large DWTW (case study : Rand Water). During the current study physical, chemical and biological water quality data from 2000 to 2009, measured in the Vaal Dam and the 20km long canal supplying the Zuikerbosch DWTW of Rand Water, has been used to develop models for the prediction of Anabaena sp., Microcystis sp., the cyanotoxin microcystin and the taste and odour compound geosmin for different prediction or forecasting times in the source water. For the development and first stage of testing the models, 75% of the dataset was used to train the models and the remaining 25% of the dataset was used to test the models. Boot-strapping was used to determine which 75% of the dataset was to be used as the training dataset and which 25% as the testing dataset. Models were also tested with 2 to 3 years of so called “unseen data” (Vaal Dam 2010 – 2012) i.e. data not used at any stage during the model development. Fifty different models were developed for each set of “x input variables = 1 output variable” chosen beforehand. From the 50 models, the best model between the measured data and the predicted data was chosen. Sensitivity analyses were also performed on all input variables to determine the variables that have the largest impact on the result of the output. This study have shown that hybrid evolutionary algorithms can successfully be used to develop relatively accurate forecasting models, which can predict cyanobacterial cell concentrations (particularly Anabaena sp. and Microcystis sp.), as well as the cyanotoxin microcystin concentration in the Vaal Dam, for up to 21 days in advance (depending on the output variable and the model applied). The forecasting models that performed the best were those forecasting 7 days in advance (R2 = 0.86, 0.91 and 0.75 for Anabaena[7], Microcystis[7] and microcystin[7] respectively). Although no optimisation strategies were performed, the models developed during this study were generally more accurate than most models developed by other authors utilising the same concepts and even models optimised by hill climbing and/or differential evolution. It is speculated that including “initial cyanobacteria inoculum” as input variable (which is unique to this study), is most probably the reason for the better performing models. The results show that models developed from on-line (in situ) measureable data only, are almost as good as the models developed by using all possible input variables. The reason is most probably because “initial cyanobacteria inoculum” – the variable towards which the output result showed the greatest sensitivity – is included in these models. Generally models predicting Microcystis sp. in the Vaal Dam were more accurate than models predicting Anabaena sp. concentrations and models with a shorter prediction time (e.g. 7 days in advance) were statistically more accurate than models with longer prediction times (e.g. 14 or 21 days in advance). The multi-barrier approach in risk reduction, as promoted by the concept of water safety plans under the banner of the Blue Drop Certification Program, lends itself to the application of future predictions of water quality variables. In this study, prediction models of Anabaena sp., Microcystis sp. and microcystin concentrations 7 days in advance from the Vaal Dam, as well as geosmin concentration 7 days in advance from the canal were incorporated into the proposed incident management protocols. This was managed by adding an additional “Prediction Monitoring Level” to Rand Waters’ microcystin and taste and odour incident management protocols, to also include future predictions of cyanobacteria (Anabaena sp. and Microcystis sp.), microcystin and geosmin. The novelty of this study was the incorporation of future predictions into the water safety plan of a DWTW which has never been done before. This adds another barrier in the potential exposure of drinking water consumers to harmful and aesthetically unacceptable organic compounds produced by cyanobacteria. / PhD (Botany), North-West University, Potchefstroom Campus, 2015

Water is the most essential resource for life. In cases where drinking water is processed from surface water it is important to ensure the raw water is of good quality, and is suitable for processing through the water treatment plant. The drinking water for Västerås is sourced from Västeråsfjärden, in the western side of Lake Mälaren. The city itself is home to marinas, ports, a wastewater treatment plant, the Svartån outlet, sewage pumping stations and stormwater outlets. Because of the negative effects these activities have on surface water quality, Mälarenergi AB is interested in relocating the raw water intake point to Granfjärden, 10 km east of Västeråsfjärden. At Granfjärden the intake point would be less exposed to the activities in Västerås, and could be placed at a greater depth, resulting in better water quality. In this Master’s thesis the water quality and the pollution risks at Västeråsfjärden and Granfjärden sites are compared. Existing water quality data were compared, and pollution risks were investigated in two ways. Firstly potential risks in the catchment area were identified through compiling previously reported information and map analysis. Secondly, possible accident scenarios from shipping were identified. Following this, SMHI simulated the accident scenarios and their estimated effects on the two sites were then assessed.   This research shows that the water quality difference between sites is small but key differences exist in the levels of organic matter, color, transparency and temperature, making the Granfjärden location preferable. Potential problems associated with the low oxygen levels found during the end of summer at Granfjärden may be addressed by temporarily raising the intake point. It should be noted however that this temporary solution may increase the exposure to pollution. In conclusion, accident scenario simulations showed the potential concentration of pollutants at both sites is low, with effluents diluted at least 1000 times. Prevailing southwesterly and westerly winds occuring at both intake points generate a clockwise circulation in Västeråsfjärden.  This causes all effluents from urban activities to reach that intake point, which is the most notable risk associated with this site.  In contrast, the two largest risks for the Granfjärden site are shipping effluents and the microbiological load from individual sewage treatment systems and animal waste. / Vatten är vårt viktigaste livsmedel och en förutsättning för allt liv. I de fall där råvatten för beredning av dricksvatten tas från ytvatten är det ytterst viktigt att säkerställa en bra vattenkvalitet, lämpat för dricksvattenberedning. Västerås stad tar idag sitt råvatten från Västeråsfjärden, i Mälarens västra delar, 3 km från Västerås stad. I staden finns bl.a. småbåtshamnar, oljehamn, avloppsreningsverk, Svartåns utlopp, nödbräddavlopp, avloppspumpstationer och dagvattenutsläpp. Dessa aktiviteter påverkar vattenkvaliteten i fjärden negativt och därför har Mälarenergi AB valt att undersöka möjligheterna att flytta intaget till Granfjärden, 10 km öster om Västeråsfjärden. Där skulle råvattenintaget inte vara lika utsatt för samhällets direkt negativa vattenpåverkan. Intaget kan läggas på ett större djup och där kan vattenkvaliteten vara bättre och mindre riskutsatt. I detta examensarbete har vattenkvaliteten och föroreningsriskerna jämförts mellan fjärdarna. Analysresultat från provtagningar i Granfjärden jämfördes med prover från Västeråsfjärden. Riskerna behandlades i två delar. I den första delen identifierades föroreningsrisker genom att sammanställa material från tidigare projekt samt genom att studera kartor. I den andra delen togs olycksscenarion inom sjöfarten fram. SMHI simulerade dessa scenarion och en bedömning gjordes sedan över hur riskutsatta de båda råvattenintagen är. Trots det stora avståndet från Västerås stad till Granfjärden var skillnaden i vattenkvalitet mellan fjärdarna förvånansvärt liten, men skillnader påvisades för några av de analyserade parametrarna. Granfjärdens bottenvatten hade signifikant lägre halter organiskt material, lägre färgtal och lägre temperatur än det nuvarande råvattenintaget. Däremot förekom lägre syrgashalter i slutet av sommaren än vid råvattenintaget i Västeråsfjärden. Om problem skulle uppstå i dricksvattenberedningen till följd av låga syrgashalter finns möjlighet att byta till ett grundare intag vid samma punkt. Det grundare intaget är dock mer utsatt för risker än det djupare. Samtliga utsläpp från de simulerade olyckorna späddes ut minst 1000 gånger innan de spred sig till råvattenintagen. Båda råvattenintagen är som mest utsatta vid sydvästlig och västlig vind. I Västeråsfjärden ger dessa vindriktningar en medurs strömningsbild i fjärden, vilket innebär att föroreningsutsläpp från staden förs mot råvattenintaget. De största riskerna för råvattenintaget i Granfjärden är utsläpp i farleden och den mikrobiologiska belastningen från enskilda avlopp och djurhållning. I Västeråsfjärden är den största riskfaktorn utsläpp från stadens aktiviteter och verksamheter längs den östra stranden.