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Theses and dissertations (Engineering and Built Environment)

Permanent URI for this collectionhttp://ir-dev.dut.ac.za/handle/10321/10

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    Development of a multi-criteria decision-support tool for improving water quality to assist with engineering infrastructure and catchment management
    (2024-05) Ngubane, Zesizwe; Sokolova, Ekaterina; Stenström, Thor-Axel; Dzwairo, Bloodless
    Research combining water quality modelling, quantitative chemical/microbial risk assessment, and stakeholder engagement to prioritise catchment areas facing water pollution problems to devise effective pollution mitigation strategies are limited. This research therefore aimed to address this gap by providing a practical and comprehensive framework that supports wellinformed decision-making processes in water pollution alleviation. By integrating multiple criteria and catchment aspects, this framework can assist infrastructure, operational, and ecological managers within a catchment in prioritising best management practices (BMPs) to reduce pollution and mitigate against potential resultant impacts. Given this context, uMsunduzi catchment, in KwaZulu-Natal, South Africa was chosen as a study site. UMsunduzi River is a major tributary of uMngeni River that is used for water supply to the cities of Pietermaritzburg and Durban. The study begins with the data synthesis from diverse sources of scientific data to identify chemical and microbial hazards, utilising a water quality modelling tool to map point and nonpoint source pollution in the catchment. The assessment encompasses the presence of pathogens such as Cryptosporidium and Escherichia coli (E. coli) in the catchment, with rural areas showing a greater contribution from animal sources, while urban areas are affected by impaired wastewater infrastructure. Quantitative microbial risk assessment (QMRA) was conducted, assuming no water treatment within the catchment. The investigation considered multiple exposure routes, including domestic drinking and recreational activities for both adults and children. The results indicate that the probability of infection from Cryptosporidium and E. coli exceeds acceptable levels set by South African water quality guidelines and the World Health Organization. The assessment further included a chemical risk assessment on various chemical groups, including organochlorinated pesticides (OCPs), pharmaceuticals and personal care products (PPCPs), heavy metals, nitrates, and phosphates. Elevated carcinogenic risks were observed for most OCPs, while noncarcinogenic pesticide effects pose long-term risks. Heavy metals and PPCPs are within sub-risk levels, but phosphates have notable ecological and health impacts, particularly in Inanda Dam, a key source of potable water for Durban. In this study, a unique contribution is made by incorporating both chemical and microbial risk assessment. Furthermore, the risk assessment methodology not only encompasses various chemical pollutants and exposure pathways but addresses the nuanced issue of water consumption variability between children and adults. To address these identified risks, a multi-criteria decision analysis methodology is employed to engage stakeholders in the risk management process. Affected, involved, and interested stakeholders, along with economic, environmental, and social criteria, contribute to the selection of Best Management Practices (BMPs). The Simple Multi-Attribute Rating Technique for Enhanced Stakeholder Take-up (SMARTEST) is utilised to identify suitable interventions. The study culminates in the recommendation of BMPs that aim to change behaviour, including public education on livestock grazing management, safe medication disposal, and responsible fertilizer and pesticide use. Pollution management measures, such as solid waste control and river cleanup, are suggested, along with infrastructure management improvements, like sewer system maintenance. This research strived to bridge the gap in water pollution alleviation by presenting a practical and comprehensive framework designed to support well-informed decision-making processes. This framework, with its integration of multiple criteria and considerations, stands poised to aid infrastructure, operational, and ecological managers within a catchment in prioritising BMPs aimed at reducing pollution and mitigating resultant health impacts.
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    Evaluation of water resource management systems in eThekwini Municipality
    (2024-05) Faya, Nosipho Buhle; Anugwo, Iruka C.; Twala, Bhekisipho
    Water is an essential and critical resource for human, animal and plant survival and our continuing existence on planet earth. Water is increasingly becoming a scarce resource, and the issue of water scarcity has been exacerbated in intensity by climate change, as well as aging water resource infrastructure in many countries; such as the republic of South Africa. This study aimed at evaluating the water resource management systems, in that is rooted in a qualitative research method and phenomenological paradigm. Thus, primary data were collected from personnel in high and strategic positions in the government entity, eThekwini Municipality Water and Sanitation. This qualitative data was then subjected to content analysis and themes. The study findings are based on the eThekwini region and its resiliency and adaptability to climate change. In order to achieve that, this study utilized an in-depth interview and semi-structured interview approach to garner respondents’ perceptions, opinions, expertise, judgement and experiences on issues of water resources management systems and infrastructure resiliency and adaptability to the impact of climate change in Durban. The data revealed that the current state of water resource infrastructure is not satisfactory, or resilient enough to withstand the impact of climate. The study findings also indicated the urgent need for the eThekwini municipality’s water resource infrastructure to be upgraded for optimal operation and for resiliency to environmental and technical challenges. The study further reveals that the eThekwini municipality is considering embarking on joint venture projects that would adopt the innovative concept of reusing, remixing and recycling treated wastewater, as well as the installation of desalination plants for effective water resources management. From our findings, we saw that eThekwini municipality needs to adopt new technologies that would enable integrated and adaptive, resilient components in their water resource management systems. The study recommended that eThekwini municipality should endeavour to strive towards upgrading the current state of its water resource infrastructure so that it is in a satisfactory state, and resilient enough to withstand impact of climate change.
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    Water supply challenges in urban and rural areas of Eastern Cape
    (2020-05-05) Dolo, Mpumelelo; Allopi, Dhiren
    Water is regarded as the most important substance found on earth. There is no substitute for it. The daily running of production businesses, industrial firms and agricultural production that help sustain the economy of countries are largely dependent on the availability of water for them to function. The importance of water cannot be over emphasised. The food which is consumed daily depends on water; it can therefore be safely concluded that without water there would be no food, and without food there would be no life. Despite the importance of water in relation to human life, animals and plants, research studies show that the its availability becoming increasingly deficient around the globe. Water levels of major dams and rivers around the world are dropping, limiting the supply of potable water to those dependent on them. Global warming is one factor that is influencing the dropping of water levels, through evaporation. Other factors include climate change, drought and population growth. In South Africa, the government has been fighting a continuous battle of trying to address the backlog of water infrastructure, particularly in the areas which were disadvantaged by the apartheid government. These areas include rural areas, small towns (semi-urban) and townships. The Eastern Cape province in South Africa is top of the list from a backlog point of view. Rural dwellers migrate to urban areas for various reasons such as better education, better health care, job opportunities and more efficient services. Water supply is one of the services which is more adequately supplied in the cities compared to the rural areas. Even though the supplied water in the urban areas of the Eastern Cape is not the best standard when compared to other cities around the country or the world, it is still at an acceptable standard. Thus, this study was conducted to seek ways of improving the supply of water in the urban and rural areas of the Eastern Cape. The availability and the quality of water differs between the urban and rural areas. The purpose of this study was to seek ways of bridging the gap between these areas while improving the standard of water supply in both rural and urban areas. While working towards improving the lives of the Eastern Cape people, the study also seeks to promote water preservation and awareness to the people of the province. In order to find better alternatives which have been tested in various places around the world, an in-depth literature review was conducted in the study. This functioned as an effective comparison of what is obtained in different places around the world and the context of this study, which is the Eastern Cape. A survey method was used to gather data regarding the problems surrounding water supply and options that could be adopted to remedy those problems. The survey was conducted in the form of a self-observation assessment, questionnaire for households in urban and rural areas and interview sessions with prominent government entities and local technical service providers. The survey covered the whole spectrum of individuals and groups that play a major role in the supply and usage of water. The study was conducted within three municipalities of the Eastern Cape. These municipalities cover approximately two-third of the Eastern Cape considering the size of population in those areas. The municipalities covered by the study were: Amathole District Municipality (ADM), Buffalo City Metropolitan Municipality (BCMM) and OR Tambo District Municipality (ORTDM). The findings from the study showed that indeed the standard of water supply between urban and rural areas was not equal. This relates to the purification methods, the convenience of collecting water by users, the quality of infrastructure being constructed (due to good or poor monitoring during construction) and the quality of the water as well as operation and maintenance response from the various service providers. Moreover, it was found that there was an acceptable level of awareness by citizens when it comes to using water, and precautions to save it were being taken by some. However, some dominant factors such as poor management, poor infrastructure resulting in leaks, climate change, run-offs and population growth were putting a strain on the existing water resources which is not coping with the increasing demand by people. Recommendations made in the study to balance the supply of water in rural areas and urban areas include: improving the purification of water so as to achieve a standard quality within the Eastern Cape; that rural areas be allowed to have an option of having yard or house connections, particularly those who are willing to pay rates at a scale suiting their class or standard; and that water service providers make it their responsibility to extend reticulation networks if there is expansion or development of more houses in rural areas in order to keep the distance minimal to standpipes