Tesi: "Urban water supply systems"

1

Mouritz, Mike. "Sustainable urban water systems : policy and professional praxis /". Mouritz, Mike (1996) Sustainable urban water systems: policy and professional praxis. PhD thesis, Murdoch University, 1996. http://researchrepository.murdoch.edu.au/211/.

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The provision of water, wastewater and stormwater infrastructure is an essential ingredient of cities. However, questions are being raised about the type and form of urban infrastructure, for economic and environmental reasons. Traditionally these techologies have offered linear solutions, drawing increasing volumes of water into cities and discharging waste at ever increasing levels, causing escalating stress on the environment. In addition the costs of water infrastructure provision and replacement, both in the developing and developed world, is becoming prohibitive. In response, a new paradigm has been called for and new solutions are emerging that have been labelled as Integrated Urban Water Management (IUWM). This concept can be considered to consist of both technical and philosophical dimensions, and represents a new form of professional praxis. However, the adoption of these techniques and concepts is constrained by the inertia of the existing urban water systems. It is therefore argued that the introduction of any change must occur across a number of dimensions of the technoeconomic system of the city. These dimensions-artefacts and technical systems (i.e. the technology and knowledge systems), professional praxis and socio-political context (i.e. institutions, culture and politics) and biophysical realities and world views (i.e. the environment and underlying values) - provide a framework for analysis of the change process - both how it is occurring and how it needs to occur. This framework is used to illustrate the link between environment values and the process of technological innovation, and points to the need for the emerging values and innovations to be institutionalised into the professional praxis and socio-political context of society. Specifically, it is argued that a new form of transdisciplinary professional praxis is emerging and needs to be cultivated. A broad review of the literature, an evaluation of selected emerging technologies and three case studies are used to illustrate and argue this position. These examples show the potential economic, social and environmental benefits of IUWM and provide some insight into the potential which this approach has to influence the form and structure of the city and at the same time highlighting the institutional arrangements required to manage urban water systems.

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2

Kizito, Frank. "Water supply management in an urban utility a prototype decision support framework /". Doctoral thesis, Stockholm : Skolan för arkitektur och samhällsbyggnad, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11900.

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3

Cortés, Calderón Sofía Valeria. "Embracing complexity: Dynamics governing urban drinking water supply security in Mexico City". Thesis, Stockholms universitet, Stockholm Resilience Centre, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-188976.

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Drinking water supply insecurity is globally on the rise, and prevalent in most low and middle-income urban areas. Multiple responses have emerged to cope with the lack of a reliable and equitable supply of safe and sufficient drinking water in cities, which presents a wide range of social-ecological implications. Yet, many of the analyses to date are focused on predominantly technological, ecological, and economic perspectives, overlooking broader cultural and political dimensions. What are the elements and the interrelationship between them that sustain the lack of drinking water supply security at an urban scale? The empirical case study is located in Mexico City, the capital city of one of the most drinking water-insecure countries globally and among the world’s five largest metropolitan areas. Qualitative data is elicited from a literature review and semi-structured interviews with key experts and urban stakeholders. The results provide an integrated understanding of the proposed system structure that created and maintain the water supply problem in the long-term. Hindrances include knowledge lock-ins and critical dynamics that inhibit the political support to transition towards a drinking water security scenario. This study shows that drinking water supply crisis in the study area and other cities with similar conditions need to be understood as multi-dimensional and from a system perspective, by challenging underlying assumptions and embracing interconnectedness. Key feedback mechanisms are presented in causal loop diagrams, allowing the exploration of higher-order leverage points to reduce existing path-dependencies as one increasingly important research area, and potentially relevant for decision-makers.

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4

Witte, Brandt. "Reforming urban water supply systems in developing countries : a case study of Conakry, Guinea". Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11145.

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5

Kizito, Frank. "Development of Decision Support Tools for Urban Water Supply Management in Uganda". Licentiate thesis, Stockholm : Mark- och vattenteknik, Land and Water Resource Engineering, Kungliga Tekniska högskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4803.

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6

Kilanko-Oluwasanya, Grace Olutope. "Better safe than sorry : towards appropriate water safety plans for urban self supply systems". Thesis, Cranfield University, 2009. http://dspace.lib.cranfield.ac.uk/handle/1826/4453.

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Self Supply Systems (SSS) can be defined as privately owned household level water sources. The research focus is on urban self supply hand dug wells in Abeokuta, Nigeria. Self supply wells serve an estimated 45% of Abeokuta’s population. SSS can be gradually upgraded to improve water quality, but water quality can also be improved through effective risk management. The World Health Organization (WHO) has developed a risk management tool known as Water Safety Plans (WSP), but the tool has not been tried for SSS. This research focuses on the relevance of the generic WHO water safety plans tool to SSS, with the aim to develop an appropriate water safety framework for self supply sources to ensure acceptable household water. Water from self supply wells is used for both ingestion and non-ingestion household activities. The water quality of the sources is poor and not safe for consumption with faecal coliform counts in excess of 100 cfu/100 ml of water. Self supply wells in Abeokuta are plagued by four main water safety threats; style of source operation – primarily through bucket and rope -, construction problems, proximity to sources of contamination, and user’s hygiene practices. Users are in denial of the health consequences of unsafe water. There is a predominantly reactive attitude to water safety management. The main source management approaches include access and hygiene management. To appropriate existing WSP to SSS, source and water safety control measures require user acceptability to be sustainable in terms of adoption and compliance. Incentives are needed for the adoption of SSS water safety plans. A two- phase supporting program is necessary: awareness and enlightenment campaigns and relevant training activities. Water safety development for self supply wells need to be initiated and coordinated by an established institution other than the source owners. This research suggests the Department of Public Health as the institution to facilitate the development of water safety plans for SSS in Abeokuta, Nigeria.

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7

Dhakal, Raju S. "Evaluating residential satisfaction with an innovative dual water supply system in water sensitive urban development". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/867.

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The Australian water industry is facing two major challenges: a rise in water demand due to a growing population and a decrease in rainfall availability due to a drying climate. This situation has triggered a re-evaluation of traditional water schemes and promoted consideration of alternatives for sustainable urban water management. One possibility is to replace drinking water usage in garden and outdoor irrigation with non-potable groundwater. This could save almost half of the water supplied in the residential sector, which is the biggest consumer of scheme water in most Australian cities. A major hurdle for the success of such fit-for-purpose groundwater schemes can be the lack of the resident’s participation and support. Currently there are uncertainties about the dynamic nature of individual’s attitudes in terms of satisfaction and accepting behaviours towards the fit-for-purpose water use. This can cause ambiguity in planning and implementation of such projects. The main purpose of this thesis is to address the following specific research questions: What are the factors that determine residential satisfaction with and behaviours towards the fit-for-purpose groundwater system? and What are the implications of such water system for community, water utilities and urban planners? These questions have been addressed through a quasi-experimental study utilizing two northern suburbs in Perth metropolitan: Ridgewood and “The Green”. “The Green” is selected as an experimental suburb and Ridgewood is selected as a control suburb, which is a standard metropolitan suburb having the usual main drinking water system. The use of non-drinking groundwater through the dual water supply system in “The Green” began in 2008 alongside the main water scheme. A broad spectrum of parallel literature from many disciplines was drawn upon to inform the research. Concurrent preliminary informal conversations with local residents and a number of field observations were helpful in refining and contextualising the research hypotheses regarding the determinants of residential satisfaction with the fit-for-purpose groundwater supply system in the context of water sensitive urban development. An exploratory mixed method approach was adopted starting with qualitative preliminary interviews with local residents to inform the development of a survey instrument. This was followed by the administration of the survey questionnaires at household level to collect quantitative data to measure the relationship among variables and test a model of residential satisfaction. The survey data and the secondary data about residential water consumption were analysed to develop a workable model for residential satisfaction with and behaviour towards the dual water supply system and water sensitive urban environment. Finally, qualitative information during stakeholder interviews, meetings, and seminars was used to interpret the planning implications of the model and behavioural responses towards the water system and urban development. The research results indicated that the majority of residents (70%) are satisfied with the nondrinking groundwater supply system in their home and neighbourhood. In “The Green”, the household drinking water consumption was reduced by 40% compared to the metropolitan average; however, excessive garden watering exemptions for new garden establishment caused 30% more water usage in “The Green” than the metropolitan average. This study found that the major components of residential environment satisfaction were the neighbourhood, neighbours, and home. Home satisfaction in “The Green” was determined mainly by home attributes and the garden satisfaction, which in turn was dependent upon garden attributes and satisfaction with the groundwater system. In this way, groundwater satisfaction had an indirect impact on home satisfaction mediated by garden satisfaction. The major determinants of groundwater satisfaction were: positive perceptions of operational issues, and risk of groundwater use (negative relationship), and preference for continuation of the groundwater system after its trial period. The major research findings are explained in Chapter Six, Seven, and Eight. The dynamic nature of community attitudes and community behaviours towards the fit-for-purpose water projects at urban settings were explored, and the planning and development consequences of the implementation of the alternative water systems were explained. The results of this study are highly applicable for water providers, urban planners, and community developers in promoting the successful implementation as well as improvement of fit-for-purpose water systems from a policy perspective. This thesis equally contributes to building knowledge and understanding of residential satisfaction and its relationship to innovative dual water systems in water sensitive urban environments. It facilitates the sustainable management and planning of urban water resources. The research also demonstrates the need to integrate general models of community satisfaction with specific water system attitudes to provide an indication of the role of water supply systems in the overall success of water sensitive developments.

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8

Cohen, Elliot J. "The water footprint of urban energy systems| Concepts, methods and applications for assessing electricity supply risk factors". Thesis, University of Colorado at Denver, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3621820.

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This dissertation adds to the body of knowledge of the water-energy nexus in four measurable ways. First, a water withdrawal footprint of energy supply (WWFES) to cities was developed, and placed it in the context of other water footprints defined in the literature. The WWFES provides a novel way to quantify direct and indirect water requirements to satisfy urban energy demand. The magnitude of the WWFES for Denver, Colorado was found to be 381 liters/person/day and 66% as large as all direct water uses in the city combined (mean estimate). This finding is relevant to urban sustainability planning as it shows significant water conservation may be achieved through energy efficiency and energy conservation.

Next, we demonstrate the robustness of the WWFES method for a rapidly developing city (Delhi) with unique energy requirements, energy infrastructure and data availability compared to the initial test case (Denver). Data collected for the Indian power sector enabled exploration of spatial- and temporal-variability of electricity supply to cities and the associated dynamic WWFES. Integrating over both space and time for one year, we estimate the water requirements of electricity production alone to be 36% as large as municipal water supply for Delhi, compared to 16% for Denver. In both cases, this highlights that electricity supply, like municipal supply, can be at risk during drought or other hydrological extremes, corroborated by interviews with industry experts.

The third and fourth contributions of this dissertation are to place water-related constraints to power generation in the context of other system risks using both social science methods and data-driven statistical analysis. For the former, a survey was administered to electricity infrastructure operators serving Delhi with three objectives: (1) identify and rank system risks to power supply reliability based on industry perceptions of risk; (2) identify and rank current and future service provision priorities; and (3) collect social network data regarding interaction between infrastructure operators. For the latter, an empirical study of electricity supply reliability in Northern India was conducted in a hierarchical modeling framework to assess the contribution of structural, environmental and supply-chain constraints to grid reliability. Model results indicate the WWFES is a statistically significant predictor of power supply reliability in Northern India when we control for structural, climate and supply-chain covariates. These results highlight the importance of the WWFES when evaluating risks to, and reliability of, trans-boundary energy systems.

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9

Asante-Wusu, Isaac. "GEOGRAPHY OF URBAN WATER SECURITY AND VULNERABILITY: CASE STUDIES OF THREE LOCALITIES IN THE ACCRA-TEMA CITY-REGION, GHANA". Miami University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=miami1497868343954842.

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10

Berg, Aaron Andrew, e University of Lethbridge Faculty of Arts and Science. "Urban impacts on a prairie groundwater system : estimation of anthropogenic contributions of water and potential effects on water table development". Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 1997, 1997. http://hdl.handle.net/10133/65.

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In subhumid to arid climates throughout the world, recharge to groundwater in urban areas is often found to be higher than pre-urbanization rates, despite an increased percentage of impermeable surfaces. Groundwater recharge in the city of Lethbridge is substantially higher than recharge rates prior to urbanization, resulting in the formation of perched water table conditions. High perched water table conditions, typically at depths between one and 2.5 metres, have created problems for the City and University of Lethbridge, including the increased occurrence of slope failures along nearby coulees. This study estimates of the volume of excess water available for groundwater recharge through the practices of urban turfgrass irrigation, and water storage. Between May and September, 1990-1996 irrigation was applied far above evapotranspiration demands, resulting in large volumes of water available for groundwater recharge in the Varsity Village subdivision of the City of Lethbridge. The relationship between the amount of water applied and the development of perched water table systems was strong enough that equations between inputs and water table depth could be derived, and used to predict water table elevation.
xiii, 190 leaves : ill., maps ; 28 cm.

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11

Yen, Jeffrey Lee. "A system model for assessing water consumption across transportation modes in urban mobility networks". Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39527.

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Energy and environmental impacts are two factors that will influence urban region composition in the near future. One emerging issue is the effect on water usage resulting from changes in regional or urban transportation trends. With many regions experiencing stresses on water availability, transportation planners and users need to combine information on transportation-related water consumption for any region and assess potential impacts on local water resources from the expansion of alternative transportation modes. This thesis will focus on use-phase water consumption factors for multiple vehicle modes, energy and fuel pathways, roads, and vehicle infrastructure for a given transportation network. While there are studies examining life cycle impacts for energy generation and vehicle usage, few repeatable models exist for assessing overall water consumption across several transportation modes within urban regions. As such, the question is: is it possible to develop a traceable decision support model that combines and assesses water consumption from transportation modes and related mobility infrastructure for a given mobility network? Based on this, an object-oriented system model of transportation elements was developed using the Systems Modeling Language (SysML) and Model-Based Systems Engineering principles to compare water consumption across vehicle modes for assessing the resiliency of existing infrastructure and water resources. To demonstrate the intent of this model, daily network usage water consumption will be analyzed for current and alternative network scenarios projected by policies regarding the expansion of alternative energy. The model is expected to show variations in water consumption due to fluctuations in energy pathways, market shares, and driving conditions, from which the model should help determine the feasibility of expanding alterative vehicles and fuels in these networks. While spatially explicit data is limited compared to the national averages that are used as model inputs, the analytical framework within this model closely follows that of existing assessments and the reusable nature of SysML model elements allows for the future expansion of additional transportation modes and infrastructure as well as other environmental analyses.

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12

Aydin, Nazli Yonca [Verfasser], e Theo G. [Akademischer Betreuer] Schmitt. "Scenario-Based Sustainability Assessment to Provide Interactive Decision Support for the Long-Term Transition of Urban Water Supply Systems / Nazli Yonca Aydin. Betreuer: Theo G. Schmitt". Kaiserslautern : Technische Universität Kaiserslautern, 2014. http://d-nb.info/106294805X/34.

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13

Mbanaso, Michael Udochukwu. "Urban Service Delivery System and Federal Government Bureaucracy: A Structural Analysis of Spatial Distribution of Water Supply in a Suburban Community of Metropolitan Lagos". PDXScholar, 1989. https://pdxscholar.library.pdx.edu/open_access_etds/1234.

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This study identifies the prevailing scarcity of urban public services and the conceptual relations among service delivery, patronage, bureaucratic activities and structural factors in the Lagos Metropolitan region. It examines the extent to which clientelism, bureaucratic decision rules and structural theoretical models explain water service delivery patterns in Festival Town (Festac), a suburb of Lagos, Nigeria. The unprecedented pace of growth of the Lagos Metropolis since the mid-twentieth century gave rise to the spectacular spatial expansion of the continuous built up region. Urban industrial and governmental institutions have not kept pace with the population growth rate of Lagos. This demographic trend also continues to tax the urban service delivery system. The federal government policy proscription entailed the planning and creation of a new town, Festival Town (Festac), as a response to addressing the urban public service problem in the Greater Lagos. Festac is well serviced with modern urban infrastructural facilities for the delivery of water supply and water related services. In recent years, however, the local residents of Festac have been faced with a similar problem in water supply which is not different from that experienced by urban residents in other parts of Lagos. The painstaking efforts that detailed a pre-planned, designed and carefully considered development of a new urban community have not succeeded in creating a regularly functioning delivery of water supply and water related services. Various analytical tools were utilyzed in conducting the study. The study concludes that the central factors in the prevailing scarcity of water supply in Festac are technology and infrastructural dependence and dwindling federal state revenues, all of which exacerbate the internal production of essential urban public services and thereby making delivery problematic. The findings presented in this study demonstrate the significance of the specific articulation expressed in the link between the Nigerian export sector, the fiscal capacity of the federal state and public service financing. This study recommends that if the Nigerian public service delivery system is to overcome its contemporary problems, policies should be adopted which largely depend on existing internal resources.

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Barbosa, Leonardo Cassimiro. "As redes técnicas sanitárias na estruturação do território: análise da cidade de Maringa-PR entre 1947-1980". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/102/102132/tde-13102016-100429/.

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A cidade de Maringá, implantada ex novo, surge com status de cidade moderna em razão do seu plano urbanístico, que apresenta ressonâncias do ideário garden city, do zoning, do movimento city beautiful e do pensamento higienista. Contudo, as redes técnicas, elementos característicos da cidade moderna, demoraram a se estabelecer, pois a CTNP/CMNP, agente privado responsável pelo plano de colonização no qual a cidade se insere, não tinha as infraestruturas urbanas como prioridade nas cidades que implantara. Entendendo a cidade por meio da interação entre tecnologia e sociedade, propõe-se a análise da cidade de Maringá por meio da inter-relação das redes técnicas sanitárias com o desenvolvimento e crescimento urbano. As principais fontes documentais advieram da análise de notícias veiculadas em jornais da época e de projetos dos sistemas sanitários, que permitiram identificar algumas fases na administração dos serviços de saneamentos, e que guiaram a discussão do estudo, sendo estas: a fase de poços e fossas, marcada pelas ações individuais e pela ação da iniciativa privada na exploração do abastecimento de água; a fase das redes municipais, quando o município se apresenta como novo ator hegemônico no controle dos serviços sanitários; e a fase de administração dos sistemas pela concessionária estadual, transição ocorrida em 1980, ano que marca o encerramento da pesquisa por entender que, neste momento, a lógica de implantação das infraestruturas sanitárias já se encontrava estabelecida. Os resultados apontam para a capacidade de as redes técnicas sanitárias materializar no território relações de desigualdade de oportunidades, acesso e distribuição de riquezas que, no caso de Maringá, contribuíram para a criação de uma dicotomia entre a área planejada e a área pós-plano.
Owing to its urban plan echoing the ideals of a garden city, zoning features, city beautiful movement and hygienist thought, the ex novo implanted city of Maringá has been founded as a modern city. However, the technical networks, characteristics of the modern city, belatedly arrived, since the CTNP/CMNP, the private agency for the colonization plan in which the city was inserted, did not give priority to the urban infrastructure in the towns and cities it had established. Since the city is an interaction between technology and society, the city of Maringá is analyzed on its inter-relationships between sanitary technical networks and urban development and growth. The main documentary sources have been retrieved from the newspapers of the period and from the projects of sanitary systems, which identified several phases in the management in sanitary services on which this study is foregrounded: the wells and cesspools phase through individual initiatives for water supply and drainage; the phase of municipal networks in which the township was the new hegemonic agent in the control of sanitary services; the phase of outsourcing state systems as from 1980. In fact, this is the year in which current research ends since the logical implantation of sanitary infrastructure was established. Results show the capacity of sanitary technical networks to favor unequal relationships in opportunities, in the access and distribution of wealth. Inequality in Maringá contributed towards the establishment of a dichotomy between the planned area and the post-plan area.

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15

Amano, Teruyoshi. "The Effectiveness Evaluation of Urban Water Supply". 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/126743.

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16

Pineda, Pablos Nicolás. "Urban water policy in Mexico : municipalization and privatization of water services /". Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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17

Tsegaye, Seneshaw Amare. "Flexible Urban Water Distribution Systems". Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4597.

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With increasing global change pressures such as urbanization and climate change, cities of the future will experience difficulties in efficiently managing scarcer and less reliable water resources. However, projections of future global change pressures are plagued with uncertainties. This increases the difficulty in developing urban water systems that are adaptable to future uncertainty. A major component of an urban water system is the distribution system, which constitutes approximately 80-85% of the total cost of the water supply system (Swamee and Sharma, 2008). Traditionally, water distribution systems (WDS) are designed using deterministic assumptions of main model input variables such as water availability and water demand. However, these deterministic assumptions are no longer valid due to the inherent uncertainties associated with them. Hence, a new design approach is required, one that recognizes these inherent uncertainties and develops more adaptable and flexible systems capable of using their active capacity to act or respond to future alterations in a timely, performance-efficient, and cost-effective manner. This study develops a framework for the design of flexible WDS that are adaptable to new, different, or changing requirements. The framework consists of two main parts. The first part consists of several components that are important in the pre and post--processing of the least-cost design methodology of a flexible WDS. These components include: the description of uncertainties affecting WDS design, identification of potential flexibility options for WDS, generation of flexibility through optimization, and a method for assessing of flexibility. For assessment a suite of performance metrics is developed that reflect the degree of flexibility of a distribution system. These metrics focus on the capability of the WDS to respond and react to future changes. The uncertainties description focuses on the spatial and temporal variation of future demand. The second part consists of two optimization models for the design of centralized and decentralized WDS respectively. The first model generates flexible, staged development plans for the incremental growth of a centralized WDS. The second model supports the development of clustered/decentralized WDS. It is argued that these clustered systems promote flexibility as they provide internal degrees of freedom, allowing many different combinations of distribution systems to be considered. For both models a unique genetic algorithm based flexibility optimization (GAFO) model was developed that maximizes the flexibility of a WDS at the least cost. The efficacy of the developed framework and tools are demonstrated through two case study applications on real networks in Uganda. The first application looks at the design of a centralized WDS in Mbale, a small town in Eastern Uganda. Results from this application indicate that the flexibility framework is able to generate a more flexible design of the centralized system that is 4% - 50% less expensive than a conventionally designed system when compared against several future scenarios. In addition, this application highlights that the flexible design has a lower regret under different scenarios when compared to the conventionally designed system (a difference of 11.2m3/US$). The second application analyzes the design of a decentralized network in the town of Aura, a small town in Northern Uganda. A comparison of a decentralized system to a centralized system is performed, and the results indicate that the decentralized system is 24% - 34% less expensive and that these cost savings are associated with the ability of the decentralized system to be staged in a way that traces the urban growth trajectory more closely. The decentralized clustered WDS also has a lower regret (a difference of 17.7m3/US$) associated with the potential future conditions in comparison with the conventionally centralized system and hence is more flexible.

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Abiwu, Napoleon. "Private sector involvement in urban water supply management, Ghana". Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/9882.

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The performance of public utilities in low-income countries with respect to service to all customers, and particularly lower-income urban consumers, is understood to be limited in many cases. The Government of Ghana chose to implement a private sector management contract in order to deliver significant change in service delivery and financial viability. The five year management contract with Aqua Vitens Rand Limited ran from 2006 to 2011 and was not renewed. This study investigates the public utility outcomes, both as a state owned corporation and a state owned limited liability Company, and compares those outcomes with the achievements of the private operator through a Management Contract. The latter two management models operated under the oversight of the newly formed economic regulator, the Public Utility Regulatory Commission in 1999 and any effect of that regulation is considered. The hypothesis of the study developed in 2008 was that “a management contract would not provide the necessary level of empowerment, incentives and commitment and access to resources for a private operator to adequately and efficiently perform even where there is an established economic regulator with a clear mandate”. The case study approach was employed for the study data was gathered on the operations, activities, regulation and management of the urban water utility through documentary review, key-informant interviews, household surveys, public hearing meetings and user observations. However, three major cities including Accra, Kumasi and Tamale were used for the household survey. These three cities were carefully picked out taking into account the political, economic, geographical, social and cultural significance that each of the them represents and commands in Ghana.

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19

Li, Huipeng. "Hierarchical risk assessment of water supply systems". Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/2735.

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Water supply systems are usually designed, constructed, operated, and managed in an open environment, thus they are inevitably exposed to varied uncertain threats and conditions. In order to evaluate the reliability of water supply systems under threatened conditions, risk assessment has been recognised as a useful tool to identify threats, analyse vulnerabilities and risks, and select proper mitigation measures. However, due to the complexity and uncertainty of water supply systems and risks, consistent and effective assessments are hard to accomplish by using available risk techniques. With respect to this, the current study develops a new method to assess the risks in complex water supply systems by reconsidering the organisation of risk information and risk mechanism based on the concepts of object-oriented approach. Then hierarchical assessments are conducted to evaluate the risks of components and the water supply system. The current study firstly adopts object-oriented approach, a natural and straightforward mechanism of organising information of the real world systems, to represent the water supply system at both component and system levels. At the component level, components of a water supply system are viewed as different and functional objects. Associated with each object, there are states transition diagrams that explicitly describe the risk relationships between hazards/threats, possible failure states, and negative consequences. At the system level, the water supply system is viewed as a network composed of interconnected objects. Objectoriented structures of the system represent the whole/part relationships and interconnections between components. Then based on the object states transition diagrams and object-oriented structures, this study develops two types of frameworks for risk assessment, i.e., framework of aggregative risk assessment and framework of fault tree analysis. Aggregative risk assessment is to evaluate the risk levels of components, subsystems, and the overall water supply system. While fault trees are to represent the cause-effect relationships for a specific risk in the system. Assessments of these two frameworks can help decision makers to prioritise their maintenance and management strategies in water supply systems. In order to quantitatively evaluate the framework of aggregative risk, this thesis uses a fuzzy evidential reasoning method to determine the risk levels associated with components, subsystems, and the overall water supply system. Fuzzy sets theory is used to evaluate the likelihood, severity, and risk levels associated with each hazard. Dempster-Shafer theory, a typical evidential reasoning method, is adopted to aggregate the risk levels of multiple hazards along the hierarchy of aggregative risk assessment to generate risk levels of components, subsystems, and the overall water supply system. Although fuzzy sets theory and Dempster-Shafer theory have been extensively applied to various problems, their potential of conducting aggregative risk assessments is originally explored in this thesis. Finally, in order to quantitatively evaluate the cause-effect relationships in a water supply system, fuzzy fault tree analysis is adopted in this study. Results of this analysis are likelihood of the occurrence for a specific event and importance measures of the possible contributing events. These results can help risk analysts to plan their mitigation measures to effectively control risks in the water supply system.

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20

Correia, Daniel Fortuna. "Management and Control of Water Supply Systems". Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13834.

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Mestrado em Engenharia Mecânica
The fast increase in the energy’s price has brought a growing concern about the highly expensive task of transporting water. By creating an hydraulic model of the Water Supply System’s (WSS) network and predicting its behaviour, it is possible to take advantage of the energy’s tariffs, reducing the total cost on pumping activities. This thesis was developed, in association with a technology transfer project called the E-Pumping. It focuses on finding a flexible supervision and control strategy, adaptable to any existent Water Supply System (WSS), as well as forecasting the water demand on a time period chosen by the end user, so that the pumping actions could be planned to an optimum schedule, that minimizes the total operational cost. The OPC protocol, associated to a MySQL database were used to develop a flexible tool of supervision and control, due to their adaptability to function with equipments from various manufacturers, being another integrated modular part of the E-Pumping project. Furthermore, in this thesis, through the study and performance tests of several statistical models based on time series, specifically applied to this problem, a forecasting tool adaptable to any station, and whose model parameters are automatically refreshed at runtime, was developed and added to the project as another module. Both the aforementioned modules were later integrated with an Graphical User Interface (GUI) and installed in a pilot application at the ADDP’s network. The implementation of this software on WSSs across the country will reduce the water supply companies’ running costs, improving their market competition and, ultimately, lowering the water price to the end costumer.
O rápido aumento dos preços da electricidade tem provocado um aumento na preocupação com a tarefa extremamente dispendiosa de transporte de água. Através da criação de modelos hidráulicos de redes de Sistemas de Fornecimento de Água, e da previsão do seu comportamento, é possível tirar vantagem das diferentes tarifas horárias de consumo de energia, reduzindo desta forma os custos totais do bombeamento de água. Esta tese foi desenvolvida em associação com o projecto de transferência de tecnologia denominado E-Pumping. Foca-se na procura de uma estratégia de supervisão e controlo flexível e adaptável a qualquer Sistema de Fornecimento de Água existente, bem como na previsão do consumo de água durante um período escolhido pelo utilizador final, o objectivo final é permitir o planeamento de um horário óptimo que minimize o custo do consumo de energia eléctrica. O Protocolo OPC, associado a uma Base de Dados MySQL, foi usado para o desenvolvimento da ferramenta de supervisão e controlo flexível, constituindo no seu conjunto um módulo do Projecto E-Pumping. A escolha baseou-se em ambas as tecnologias serem adaptáveis a equipamentos de diferentes fabricantes. Esta tese produziu ainda uma ferramenta de previsão do consumo de água, adaptável a qualquer estação, constituindo um segundo módulo do projecto. Esta ferramenta foi obtida através do estudo e testes de performance a variados modelos baseados em séries temporais, especificamente aplicadas a este problema. Os parâmetros do modelo de base desta ferramenta são automaticamente actualizados a cada execução do programa. Ambos os módulos referidos foram integrados com uma Interface Gráfica (GUI) e implementados numa aplicação piloto instalada na rede de abastecimento de água da empresa Águas do Douro e Paiva (ADDP). A implementação deste software em Sistemas de Abastecimento de Água por todo o país reduziria os seus custos de funcionamento, melhorando a sua capacidade de competição no mercado e, em última instância, diminuindo os preços da água para o consumidor final.

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21

Alayoubi, Mzayan. "Risk Analysis for Intermittent Water Supply Systems". Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-234554.

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Intermitted Water Supply strategy is implemented commonly in some developing countries nowadays in order to minimize the water scarcity problems. Unstable hydraulic conditions in the distribution system, low pressure, high risk of water contamination, wasting water, rising costs paid by consumers and water providers, failures and problems with consumption metering and inconvenience to consumers are some of the consequences. Risk Analysis Methodology is developed to handle with intermittent water supply systems in developing countries conditions that include undesired events identification; risk estimation and risk evaluation and reduction plan, the catalogue list of potential undesired events (UE) which may occur in these types of systems have been also developed using the HAZard and OPerability technique (HAZOP). The developed methodology is implemented and tested in this research on one of the potential undesired events UE _ Low operational pressure

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22

Blignault, Samantha Paige. "Feasibility of groundwater abstraction and treatment for urban water supply". Master's thesis, University of Cape Town, 2020. http://hdl.handle.net/11427/32466.

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Water is one of Earth's most valuable resources and one of Earth's most threatened resources. Continuously increasing population growth coupled with changing climate has resulted in the depletion of water sources. As a result, investigations into alternative water sources are being conducted worldwide. One such alternative water source is groundwater abstraction. Groundwater abstraction involves the abstraction of water from an underground source. The volume of water that can be sustainably abstracted is governed by legislation. Groundwater typically requires treatment before it can be distributed to the general population for use, and thus the implementation of large-scale groundwater abstraction projects involves large capital outlays, as well as monthly operational outlays. The feasibility into the implementation of large-scale groundwater abstraction projects is therefore of interest to stakeholders involved in the water supply industry. The lifecycle of a recently implemented large-scale groundwater abstraction project was analysed in order to determine its feasibility. The project was implemented by Drakenstein Municipality in the Western Cape in 2017. The project involved identifying groundwater abstraction points that could provide sustainable volumes of water. The water quality of each groundwater abstraction point was then investigated for any outlying parameters according to SANS 241-1:2015 guidelines for potable water. Groundwater abstraction water treatment plants were then designed in order to treat the combined sustainable flow rates of water at their specific water qualities. The treated water from each groundwater abstraction water treatment plant was then analysed in order to confirm compliance with the SANS 241- 1:2015 guidelines, before the booster pumps were commissioned and commenced with their continuous supply of potable water into the network. The capital expenditure associated with each of the groundwater abstraction water treatment plants was obtained from the Engineer, Aurecon. In addition, the estimated monthly operational expenditure was computed. These expenditures were used to determine the feasibility of the large-scale groundwater abstraction project by computing the payback period and comparing this period to the design life of each of the groundwater abstraction water treatment plants. In addition, the monthly savings applicable to the municipality as a result of the project's implementation was computed. Finally, the feasibility into varying flow rates of groundwater abstraction water treatment plants, and varying water quality of groundwater abstraction points was investigated. Two sites were identified within the municipal area, each with four groundwater abstraction points capable of delivering a combined 5.18 ML/day and 1.62 ML/day. These sites were identified as Boy Louw Sportsgrounds and Parys Sportsgrounds respectively. Although the sites were only 2.60 kilometres apart, the water quality of the combined flow rates indicated that the groundwater abstraction points were accessing two different water sources. The combined sustainable flow rate at Boy Louw Sportsgrounds required turbidity, iron and manganese removal, as well as disinfection. The combined sustainable flow rate at Parys Sportsgrounds required turbidity removal and disinfection. Groundwater abstraction water treatment plants were then designed to treat the water at Boy Louw Sportsgrounds and Parys Sportsgrounds. Boy Louw Sportsgrounds involved the distribution of equipment across seven shipping containers, whilst Parys Sportsgrounds involved the distribution of equipment across three shipping containers. It was found that the groundwater abstraction project was feasible with a payback period of three years. This payback period fell well within the 10-year design life of each groundwater abstraction water treatment plant. In addition, it was found that the municipality would be subject to a 72% monthly saving in water costs as a result of utilising the groundwater abstraction water treatment plants, as opposed to purchasing water in bulk from the City of Cape Town. It was found that the payback periods of Boy Louw Sportsgrounds and Parys Sportsgrounds were two and five years respectively. Although Boy Louw Sportsgrounds delivered almost three times the potable water flow rate than that of Parys Sportsgrounds, its payback period was three years sooner. In addition, it was found that the municipal savings as a result of Boy Louw Sportsgrounds was 8% more than that of Parys Sportsgrounds. It was therefore concluded that the larger the flow rate of water to be treated, the more financially feasible the project. In addition, it was determined that the more water quality parameters lying above the upper limits of SANS 241-1:2015 guidelines for potable water, the more treatment processes would need to be implemented resulting in additional capital and operational expenditure. It was therefore concluded that the more water quality parameters requiring treatment, the less financially feasible the project. Finally, it was determined that the feasibility of the large-scale groundwater abstraction project is limited by the rate at which the municipality purchases water in bulk from the City of Cape Town. As long as the bulk water purchase tariff remains above R 2.85/m³, the project will remain feasible. Should the bulk water purchase tariff fall below this value, the project no longer remains feasible as the payback period of the project exceeds the design life of the groundwater abstraction water treatment plants.

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23

Sempewo, Jotham Ivan. "Transitioning of urban water distribution systems". Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4227/.

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The upgrade of urban water distribution systems (UWDS) amidst uncertain global change pressures is a challenging problem. To deal with this dilemma water utilities require approaches that enable UWDS to be transitioned at a minimal technical and socio-economic impact as uncertainties become known. A review of approaches for upgrading UWDS shows that existing cost models are skewed towards operation and maintenance costs without consideration for future transitionability. This thesis describes approaches for the sustainable transition of UWDS and their application on case studies. The thesis develops a conceptual framework for the analysis of UWDS transitions. It then develops a Socio-economic Impact Indicator (SII) framework based on Multi Criteria Decision Analysis and the Analytical Hierarchical Process to estimate impacts in an urban area due to UWDS transitions. It also develops an approach for modelling socio-technical transitions based on multinomial logistic regression. The thesis then develops an UWDS transition design approach that considers not only operation and maintenance costs (leakage and burst costs) but also transitionability and future socio-technical impacts costs. The developed approaches have been tested on case studies as proof of concept. Maximum cost saving can be realised when existing UWDS are upgraded with consideration of future UWDS transitionability.

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Connarty, M. C. "Optimum water pricing and capacity expansion of water supply systems /". Title page, contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phc7523.pdf.

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25

Sumadi, Pungky. "Privatization of the water-supply industry in Indonesia". Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/70229.

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26

Wutich, Amber Yoder. "The effects of urban water scarcity on sociabilty [sic] and reciprocity in Cochabamba, Bolivia". [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0013898.

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27

Ainuson, Kweku Gyan. "Ensuring adequate water supply to disadvantaged urban communities in Ghana". Connect to this title online, 2009. http://etd.lib.clemson.edu/documents/1247508537/.

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28

Ukoli-Onodipe, Grace O. "Designing optimal water supply systems for developing countries". The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1054719439.

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29

Koçak, Eyup. "Energy recovery in water supply systems using hydroturbines". Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22500.

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Abstract (sommario):

Mestrado em Engenharia Mecânica
In the last century, the main source of hydroelectric power came from conventional dams and the energy produced by hydro turbines had a fast growing. New applications of turbines in hydro power even in micro-scale projects have emerged. Water supply systems are large energy consumers due to the large amount of energy needed for pumping the water from low to high heights. However, gravity fed subsystems generally presents excess of pressure, which is lost with pressure reducing valves. Therefore, energy can be recovered from locals of excessively high flow and pressure. Nevertheless, water networks are highly complex systems and the flow conditions change instantaneously throughout the network. The control of the pressure is the top priority of the system providers and energy should be converted along with keeping the pressure to a desired level. The application of turbines appeared as an alternative to produce energy, to reduce leakage reductions and to manage network pressure. This work aims to investigate the energy production in water supply systems using micro hydro turbines. To find the optimal location for the installation of micro hydro turbine in the network, a tool is developed using the hydraulic simulator EPANET for obtaining flow regimes of each pipe. Technical feasibility analysis is automatically computed for the selection of appropriate type turbine and the CFD program ANSYS is used to design and verify the hydraulic performance of the turbine. A financial analysis is performed and has showed that energy production in water supply systems using micro turbines is a profitable alternative and a renewable solution for the world’s growing energy needs.
No século passado, a principal fonte de energia hidroelétrica provinha de barragens convencionais e a energia produzida pelas turbinas hidráulicas teve um crescimento rápido. Neste século, novas aplicações de turbinas geradoras de energia elétrica, mesmo em projetos de microescala, emergiram. Os sistemas de abastecimento de água são grandes consumidores de energia devido à grande quantidade de energia necessária para o bombeamento de água de baixas para elevadas alturas manométricas. No entanto, os subsistemas alimentados graviticamente apresentam geralmente excesso de pressão, que se perde com válvulas de redução de pressão. Portanto, a energia pode ser recuperada de locais de caudal e pressão excessivamente elevados. No entanto, as redes de água são sistemas altamente complexos cujas condições hidráulicas mudam instantaneamente em toda a rede. O controle da pressão é a principal prioridade dos fornecedores e a energia deve ser recuperada ao mesmo tempo que se mantém a pressão desejada. A aplicação de turbinas aparece como uma alternativa para produzir energia, reduzir fugas e gerir a pressão da rede. Este trabalho tem como objetivo investigar a produção de energia em sistemas de abastecimento de água usando microturbinas hidráulicas. Para encontrar a localização ideal para a instalação da microturbina hidráulicas na rede, desenvolve-se uma ferramenta que recorre ao simulador hidráulico EPANET para obter regimes de escoamento de cada conduta. A análise de viabilidade técnica é calculada automaticamente para a seleção da turbina adequada e o programa CFD ANSYS é usado para projetar e verificar o desempenho hidráulico da turbina. Uma análise financeira é realizada e mostra que a produção de energia em sistemas de abastecimento de água usando microturbinas é uma alternativa lucrativa e uma solução renovável para as crescentes necessidades energéticas do mundo.

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30

Ukoli-Onodipe, Grace. "Designing optimal water supply systems for developing countries". Columbus, Ohio : Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc%5fnum=osu1054719439.

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Thesis (Ph. D.)--Ohio State University, 2003.
Title from first page of PDF file. Document formatted into pages; contains xiv, 164 p.; also contains graphics. Includes abstract and vita. Advisor: Allan Randall, Dept. of Agricultural, Environmental & Development Economics. Includes bibliographical references (p. 147-157).

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31

Huang, Danguang. "Flexible design of urban water distribution systems". Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/2948/.

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Urban water distribution systems (UWDS) are highly inter-connected and under many uncertainties from water demand, pipe roughness, and component failure. Accurate projections of these uncertainties are almost impossible, and thus it may not be a proper method to design the system to meet its performance criteria for the forecasted scenario. The system is designed for the deterministic not for the uncertainties, as a result it may not be efficient or effective to be operated under different future scenarios. Flexible design is shown as a useful strategy to cost-effectively respond to uncertainties because of its consideration of uncertainties in advance, and has been successfully applied in many engineering systems. The objective of flexible design is to identify flexibility sources in UWDS and embed them into the system design to respond to uncertainties. The thesis discussed different terms to define the property of the system to respond to uncertainties and proposed a definition of flexibility for UWDS. It then proposed different measures to indicate flexibility value and introduced an efficient method to handle numerous uncertain parameters in the model. It also develops an efficient method to identify high value flexibility sources based on the Flexibility Index. Finally the thesis presents a flexibility-based optimisation model that enable water engineers to compare different flexible design alternatives and generate optimal solutions. A definition of flexibility in UWDS is proposed to illustrate broadly its property to respond to uncertainties, since it is not so useful, or at least in this thesis to distinguish similar terms to define the property of the system to respond to uncertainties. Identified flexibility sources by the proposed method is not useful for the flexibility-based optimization model to design a system, but it might be a powerful tool to locate the weak points in the system or provide better update options during rehabilitation of the system. The computational efficiency of the proposed flexibility-based optimisation model was demonstrated by dramatic decreasing on the number of the required hydraulic simulation in the case study. Flexible designs in the case study are more expensive than inflexible design, but have better hydraulic performance under uncertainties.

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Noiva, Karen Marie. "International comparative analysis of urban water systems". Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/115760.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Architecture, 2018.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 223-251).
This dissertation presents a new approach to structuring global diversity for a large number of urban water systems, so that trends observed in a small number of cases can contribute to a more general understanding of the spectrum of contemporary sustainability challenges faced by cities around the world. The two-part approach first uses a large number of cities (large-n, i.e. n = 142) to identify a typology which is used to guide the choice of two cases (small-n, i.e. n = 2) for further analysis. In the first part of the approach, I compare a large number (large-n) of urban water systems. Simple profiles of key attributes of urban water supply and demand-population (N), water use intensity (WN), and net annual water balance data (qNet)-are assembled from common global databases. Univariate and bivariate methods are used to identify global trends. I introduce two new indicators that benchmark urban water use intensity against climatic availability: the Water Use and Climate Index (WUCI, with units of m²) and the Potential Self-Sufficiency Ratio (Rss, unitless) and find that 65% of cities in the study have Rss >/= 1. I then use exploratory statistical clustering algorithms to identify six type of urban water systems profiles, ranging from small, wet cities with low WUCI and high Rss to large cities with high water use intensity, high WUCI, and lower Rss. In the second part of the approach, I demonstrate the use of that typology in framing case study choice for small-n international comparative analysis of urban water systems. I choose Los Angeles and Singapore from Type 4, which have large populations and high water use intensity but different climates. I apply univariate and bivariate methods to identify trends over time in water system profiles of LA and Singapore. Calculating WUCI and the Potential Self-Sufficiency Ratio for the two cases provides insight into historical behavior and future targets. Finally, I use these results to construct simple simulations to assess past behavior and future targets.
by Karen Marie Noiva.
Ph. D.

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33

Coello, Midence Balthasar Zairis Aida. "Insufficient water supply in an urban area - case study : Tegucigalpa, Honduras". Licentiate thesis, KTH, Vattenförvaltning, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-50503.

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Tegucigalpa, the capital of Honduras, has experienced an unsatisfied water demand during the last three decades. The state owned water utility in charge of the water supply of the country, SANAA, has faced this deficit by providing an intermittent water supply. The intermittent water supply has increased the gap between the rich and the poor, who cannot afford water storage facilities. Theories explain water scarcity either by low precipitation or by lack of investment in water structures. This thesis investigates the applicability of both explanations by quantifying the annual precipitation in the sub catchments with water supply potential for Tegucigalpa, and identifying the problems which caused the lack of investment into the water infrastructure. The analysis concluded that even if the annual precipitation is abundant, it is not evenly distributed in time and in space. Furthermore, it is argued that the financial limitations which hindered the lack of investment in water structures originated in the low tariffs imposed, and to the practices of the patronage system.
QC 20111207

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34

Fazakerley, Victor William. "Critical issues for the future of the Australian urban water supply industry". Thesis, Curtin University, 2005. http://hdl.handle.net/20.500.11937/1246.

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This study makes a contribution to the Australian urban water supply industry because it highlights some of the critical issues the industry faces in the future. Through the scenarios it illuminates an alternative method to develop strategies for the future. Ultimately the end result of scenario planning is not a more accurate picture of the future, but better decision making for the future. This is a significant piece of research because it demonstrates the advantages of the scenario planning process as a method to illuminate the potential future dangers and opportunities in the water industry's business environment. The scenarios can be used as a launching pad for strategic planning and to prepare the water industry for the uncertainties it faces. Water is precious and essential to life. Water supply is arguably the ultimate essential service. Australia uses about 22,000 gigalitres of water [l gigalitre (GL) = 1,000,000,000 litres, approximately 444 Olympic swimming pools (ABS 2004)] per annum across all sectors, irrigation, industry and domestic. The aim of this study was to determine the critical issues for the future of the Australian urban water supply industry. The study achieved this with the aid of scenarios that tell stories about urban water supply to the year 2025. A key to this study is the concept of organisations as living organisms, which are capable of learning and adapting to changes in their business environment. Today's business environment is constantly changing through globalisation, technological innovation and society's values. To survive, organisations must be able to anticipate and adapt to this often uncertain environment.Traditional methods, from a mechanistic perspective, of developing strategic plans for the future have a poor track record because they invariably rely on forecasting and predicting the future from historical information that, in an increasingly uncertain and fast changing world, may no longer be appropriate. Scenarios are stories about the future. They combine uncertainty and trends with creativity, insight and intuition to enable an organisation to learn and develop strategies for the future from an organic perspective. Scenarios are not predictions, but they are plausible stories about the future. The stories do allow an organisation to re-perceive a different world by questioning prevailing paradigms and assumptions. The underlying philosophical basis for scenario planning is constructivist which is consistent with the ontological position taken for this study. This study was undertaken under a qualitative research paradigm. The ontological position taken to answer the research question was constructivist with a critical perspective where realities are intangible mental constructs based on the culture and experience of individuals or groups. Constructs are more or less informed and changeable. From an epistemological perspective the constructivist position assumes that the enquirer and subject of the research are interactively linked so that findings are created. Research under a constructivist paradigm requires a hermeneutical and dialectical methodology leading to interpretation.The methodology adopted for this study was grounded research, being a modification of grounded theory and applicable to the business environment. Data were initially gathered by semi-structured interview, the objective being two fold. 1. The data were used to elicit critical issues for the future of the Australian urban water supply industry. 2. The data were used to develop 'plausible' futures for the urban water supply industry in the form of scenarios. The data were analysed using grounded research principles and organised using NVivo (Richards 1999; NVivo 2002). After two stages of analysis, 16 major categories, focusing on the future emerged from the data. In order to write the scenarios two key uncertainties critical to the future of the urban water supply industry were required for the scenario matrix. The two selected were 'Water availability' and 'Technological change' from the water industry's contextual environment. These two key uncertainties were considered to be the most uncertain and have the greatest impact on the future of the water industry. These two key uncertainties formed the context for the scenarios into which over 200 other issues were de-dimentionalised, as in the scenario planning method, and crafted into four scenarios. A time horizon of 2025 was selected for the scenarios to reflect the water industry's long term planning horizon.The scenarios were called 'Decadent water use', which depicts a future where there is plenty of water and technology addresses the cost of service delivery; 'Smart water world', which depicts a future where water is scarce but is addressed by technology providing alternative sources of water; 'Muddy waters', which depicts a future where there is plenty of water but technology does not address the cost of delivery and issues of infrastructure deterioration and 'Mad Max water world', which depicts a future where water is scarce and technology does not address the scarcity, the situation becomes a crisis. From the scenarios and using concepts from complex adaptive systems theory a number of critical issues emerged from the data. Some were at a philosophical level such as whether water, as a common good, fits with society's philosophy about water. Others were at a practical level for example expressing the criticality for the water industry to build community trust and support. The research notes the potential for further qualitative research in the fields of community attitudes and behaviours towards water, water services, recycling wastewater and the preparedness to pay for water services. In addition there is potential to further develop scenarios presented in this study; 'Decadent water use', 'Smart water world', 'Muddy waters' and 'Mad Max water world'; for the Australian urban water supply industry using the data from this research as a basis for group consultation.

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Diawuo, Felix. "Water Supply of Accra, with Emphasis on Sachet Water". Thesis, KTH, Vattenförvaltning, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99333.

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This project seeks to assess the impact of the sachet water industry on the health, socio-economic and the environmental situation of the inhabitants of Accra, the capital city of Ghana. In addressing the situation, the driving forces which have fuelled the shift of consum-er taste from the normal tap water and the traditional hand-tied-ice water products to the plastic sachet water (commonly known in as "Pure Water") are identified. Lack of access to continuous flow of improved water and the perceived poor quality of the urban water supply system as results of poor management structure are identified as some of the factors for the shift in consumers’ taste for plastic sachet and bottled drinking water. The quality of the plastic sachet is also assessed through the review of previous research results. These are confirmed by laboratory analysis of about six brands of plastic sachet water and two brands bottled drinking water. The laboratory analysis carried out assessed the microbial, physical and chemical quality of the various samples. To assess the health impacts of the products, the results from the analysis are compared with WHO guideline values and other international guideline values. Questionnaires are also administered to ascertain the socio-economic impacts of the products on the life of the young men and women as well sachet water manufacturers. From this, some measures are suggested as to how to mitigate the activities of the sachet water business to reduce its negative effects on the health, the environment and the socio-economic status of the inhabitants of the city.

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Al, Jabri Kassim. "Assessing the resilience of water supply systems in Oman". Thesis, Abertay University, 2016. https://rke.abertay.ac.uk/en/studentTheses/59b676d6-8451-4783-94dd-c9b05b7763c4.

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Water systems in the Sultanate of Oman are inevitably exposed to varied threats and hazards due to both natural and man-made hazards. Natural disasters, especially tropical cyclone Gonu in 2007, cause immense damage to water supply systems in Oman. At the same time water loss from leaks is a major operational problem. This research developed an integrated approach to identify and rank the risks to the water sources, transmission pipelines and distribution networks in Oman and suggests appropriate mitigation measures. The system resilience was evaluated and an emergency response plan for the water supplies developed. The methodology involved mining the data held by the water supply utility for risk and resilience determination and operational data to support calculations of non-revenue water. Risk factors were identified, ranked and scored at a stakeholder workshop and the operational information required was principally gathered from interviews. Finally, an emergency response plan was developed by evaluating the risk and resilience factors. The risk analysis and assessment used a Coarse Risk Analysis (CRA) approach and risk scores were generated using a simple risk matrix based on WHO recommendations. The likelihoods and consequences of a wide range of hazardous events were identified through a key workshop and subsequent questionnaires. The thesis proposes a method of translating the detailed risk evaluations into resilience scores through a methodology used in transportation networks. A water audit indicated that the percentage of NRW in Oman is greater than 35% which is similar to other Gulf countries but high internationally. The principal strategy for managing NRW used in the research was the AWWA water audit method which includes free to use software and was found to be easy to apply in Oman. The research showed that risks to the main desalination processes can be controlled but the risk due to feed water quality might remain high even after implementing mitigation measures because the intake is close to an oil port with a significant risk of oil contamination and algal blooms. The most severe risks to transmission mains were found to be associated with pipe rather than pump failure. The systems in Oman were found to be moderately resilient, the resilience of desalination plants reasonably high but the transmission mains and pumping stations are very vulnerable. The integrated strategy developed in this study has a wide applicability, particularly in the Gulf area, which may have risks from exceptional events and will be experiencing NRW. Other developing countries may also experience such risks but with different magnitudes and the risk evaluation tables could provide a useful format for further work.

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Oggins, Cy R. "Identifying and protecting community values in western water a survey of community leaders' perceptions towards rural-to-urban water transfers /". Thesis, The University of Arizona, 1990. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1990_662_sip1_w.pdf&type=application/pdf.

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Steele, Andres. "Factors impacting on the appropriateness of water treatment and supply processes for post-emergency water supply systems". Thesis, University of Surrey, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520478.

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Fisher, Karen Toni. "Meeting urban water needs : exploring water governance and development in Tagbilaran City, the Philippines /". View thesis entry in Australian Digital Theses Program, 2006. http://thesis.anu.edu.au/public/adt-ANU20061221.100356/index.html.

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40

Chakava, Yolanda. "'Transition Phase' water supply interventions in low-income urban settlements, Kenya". Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/8475.

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A multitude of transitional water supply and distribution interventions are continually piloted in Kenya’s fast-growing urban settlements to meet national and global MDG targets, yet visible problems persist regardless of the investments made. This research evaluates the performance of four interventions led by public utilities and non- governmental organisations in the low-income settlements of Nairobi, Kisumu and Nakuru counties. To understand the service improvement received by the residents, this study used qualitative data from interviews and focus group discussions and quantitative data from 1,168 household surveys. Service level analysis results showed making water more affordable using pre-paid technology reduced the effective price by 75% and increased consumption per household by 20 litres per day, resulting in the highest service progress. Improving water accessibility for the very poor via hosepipe door-step delivery reduced the burden on women carrying water by 43% although efforts failed to reduce the pricing structure, limiting the progress. Subsidised ‘first-time’ metered plot connections to increase the utility customer base experienced shortages in water supply and reluctance from landlords, restricting development. Despite showing no positive change, 81% of residents continued to rely on expensive self-supplied boreholes which were all contaminated. Although the utilities have made positive strides in service improvement, in the context of universal service this study has shown that the very poor remain the most difficult to access, forming the target of discrete interventions that experience difficulties in influencing a reliable supply, sustained price reduction and/or good water quality – essentially what is needed most. In investigating the longer term supply and demand shortfall, this study concludes that the equitable supply and innovative distribution of point source groundwater, with a bias for the poorest, could be the most resilient transitional solution for the utility to promote in the foreseeable future, out of necessity rather than desire.

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41

Van, Rensburg Francois. "Urban water security in the city of Windhoek". Thesis, Stellenbosch : Stellenbosch University, 2006. http://hdl.handle.net/10019.1/50671.

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Thesis (MPhil)--Stellenbosch University, 2006.
ENGLISH ABSTRACT: Urbanisation is a complex phenomenon and is a trend witnessed across the globe. Africa particularly has been experiencing the world’s most rapid rate of urbanization and cities are faced with the resulting pressure on natural resources. Water is one of the resources under pressure and the provision thereof is complicated by the deteriorating quality and quantity thereof. This study takes a brief look at the water situation in a water scarce region in Africa and concentrates on the urban water supply sector. It takes an in depth look at the measures used to secure water supply to a city in this very dry part of the world. The area under study is Windhoek, the capital of Namibia, situated in the southwestern corner of Africa. Namibia is the driest country in Sub-Saharan Africa and is characterised by a semi-arid nature, which results in a very hot and dry climate with erratic rainfall patterns. Windhoek has a low average rainfall associated with very high evaporation rates. No permanent water bodies exist near the city and the bulk of Windhoek’s water supply comes from storage dams quite a distance from the capital. Most of these sources of supply have been developed and are nearing the limit of their potential. A desperate need therefore exists to develop reliable additional water resources to secure the water supply especially during periods of prolonged drought. The case study gives examples of the initiatives taken by water authorities to improve the security of supply and keep up with the growing demand in the city. These initiatives include a dual pipe system for the distribution of semi-purified sewage for irrigation, reclamation of domestic sewerage, aquifer recharge and the implementation of Water Demand Management principles. An analysis of the most efficient and cost-effective means of supply augmentation namely aquifer recharge, have been balanced against the potential water savings of Water Demand Management in the city. The study also takes a brief look at the principles of Integrated Water Resource Management and how it is incorporated in the strategies used to augment supply to the city. The research found aquifer recharge as the most efficient and cost-effective means to augment supply to the city and together with Water Demand Management creates an approach complying with the goals of Integrated Water Resource management. The study concludes by identifying gaps in demand management in the city. It also suggests relevant recommendations on how to increase the effectiveness of Water Demand management.
AFRIKAANSE OPSOMMING: Verstedeliking is ‘n komplekse verskynsel en ‘n tendens wat regoor die wêreld voorkom. Die hoogste voorkoms van verstedeliking vind in Afrika plaas wat groot druk plaas op die natuurlike hulpbronne van stede. Water is een van die hulpbronne onder druk en die voorsiening daarvan word bemoeilik deur die verswakking van die kwaliteit en die beskikbaarheid daarvan. Hierdie studie konsentreer op die watersituasie in ‘n waterskaars streek in Afrika en die stedelike watervoorsieningssektor. Dit behels ‘n in diepte ondersoek na metodes wat gebruik word om die watervoorraad van die stad te verseker in hierdie droogte gesteisterd deel van die wêreld. Die gebied onder bespreking is Windhoek, die hoofstad van Namibië, wat geleë is in die Suidwestelike deel van Afrika. Namibië is die droogste land in die Sub-Saharastreek en word gekenmerk deur gereelde droogtes met ‘n gepaardgaande warm droë klimaat en onreëlmatige reënvalpatrone. Windhoek word gekenmerk deur ‘n lae gemiddelde reënval met ‘n baie hoë verdampingstempo. Geen permanente waterbronne kom in die nabyheid van die stad voor nie en die watervoorraad word gestoor in opgaardamme wat redelik ver van die hoofstad geleë is. Hierdie voorsieningsbronne is voortdurend in gebruik en die voorraad is beperk. Daar onstaan dus ‘n dringende behoefte aan betroubare bykomende waterbronne om voortdurende voorsiening aan die stad te verseker veral gedurende aanhoudende droogtes. Die gevallestudie konsentreer op voorbeelde en inisiatiewe wat deur die Water Owerhede geneem word om die voorsiening van water, aan die immergroeiende behoeftes van die stad te verbeter en te verseker. Hierdie pogings sluit in,‘n dubbele pyplynsisteem vir die verspreiding van halfgesuiwerde rioolwater vir besproeiingsdoeleindes, herwinning van huishoudelike rioolwater, herlaai van ondergrondse watervoorraad en die implimentering van wateraanvraag bestuursmaatreëls. Die geskiktste en mees koste-effektiewe metode van verhoogde watervoorsiening naamlik die herlaai van ondergrondse waterbronne, is ontleed, en die voordele opgeweeg teen die potensiële waterbesparing deur die Bestuur van Wateraanvraag in die stad. Daar is ook kortliks gekyk na die beginsels van Geintigreerde Water Bronne Bestuur en hoe dit by bestaande strategieë ingelyf is om uitbreiding van voorsiening aan die stad te verseker. Die navorsing het bevind dat die herlaai van ondergrondse waterbronne as die geskikste en mees koste-effektiewe metode beskou kan word om die verhoogde aanvraag van die stad die hoof te bied. Die studie word afgesluit deur die tekortkominge in die Water Aanvraagbestuur van die stad te identifiseer. Relevante aanbevelings word gemaak van hoe om die effektiwiteit van hierdie betrokke strategie te verbeter.

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42

Chang, Ching-Chiao. "Optimal reliability-based design of bulk water supply systems". Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/14593.

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Includes bibliographical references.
Bulk water supply systems are usually designed according to deterministic design guidelines. In South Africa, design guidelines specify that a bulk storage reservoir should have a storage capacity of 48 hours of annual average daily demand (AADD), and the feeder pipe a capacity of 1.5 times AADD (CSIR, 2000). Nel & Haarhoff (1996) proposed a stochastic analysis method that allowed the reliability of a reservoir to be estimated based on a Monte Carlo analysis of consumer demand, fire water demand and pipe failures. Van Zyl et al. (2008) developed this method further and proposed a design criterion of one failure in ten years under seasonal peak conditions. In this study, a method for the optimal design of bulk water supply systems is proposed with the design variables being the configuration of the feeder pipe system, the feeder pipe diameters (i.e. capacity), and the size of the bulk storage reservoir. The stochastic analysis method is applied to determine a trade-off curve between system cost and reliability, from which the designer can select a suitable solution. Optimisation of the bulk system was performed using the multi-objective genetic algorithm, NSGA-II. As Monte Carlo sampling can be computationally expensive, especially when large numbers of simulations are required in an optimisation exercise, a compression heuristic was implemented and refined to reduce the computational effort required of the stochastic simulation. Use of the compression heuristic instead of full Monte Carlo simulation in the reliability analysis achieved computational time savings of around 75% for the optimisation of a typical system. Application of the optimisation model showed that it was able to successfully produce a set of Pareto-optimal solutions ranging from low reliability, low cost solutions to high reliability, high cost solutions. The proposed method was first applied to a typical system, resulting in an optimal reservoir size of approximately 22 h AADD and feeder pipe capacity of 2 times AADD. This solution achieved 9% savings in total system cost compared to the South African design guidelines. In addition, the optimal solution proved to have better reliability that one designed according to South African guidelines. A sensitivity analysis demonstrated the effects of changing various system and stochastic parameters from typical to low and high values. The sensitivity results revealed that the length of the feeder pipe system has the greatest impact on both the cost and reliability of the bulk system. It was also found that a single feeder pipe is optimal in most cases, and that parallel feeder pipes are only optimal for short feeder pipe lengths. The optimisation model is capable of narrowing down the search region to a handful of possible design solutions, and can thus be used by the engineer as a tool to assist with the design of the final system.

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Vlok, Gustav. "Optimal risk-based design of bulk water supply systems". Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/12211.

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Includes abstract.
Includes bibliographical references (leaves 122-124).
Bulk water supply systems generally consist of a source of water, a conveyor (feeder pipe, canal etc.) and a storage facility. Designing bulk water supply systems includes the sizing of these components to ensure a functional system...The study follows the same methods that have been used by researchers at the University of Johannesburg in recent years. A Monte Carlo simulation method is used through the use of the Mocasim II software.

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44

Fazakerley, Victor William. "Critical issues for the future of the Australian urban water supply industry". Curtin University of Technology, Graduate School of Business, 2005. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=15971.

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This study makes a contribution to the Australian urban water supply industry because it highlights some of the critical issues the industry faces in the future. Through the scenarios it illuminates an alternative method to develop strategies for the future. Ultimately the end result of scenario planning is not a more accurate picture of the future, but better decision making for the future. This is a significant piece of research because it demonstrates the advantages of the scenario planning process as a method to illuminate the potential future dangers and opportunities in the water industry's business environment. The scenarios can be used as a launching pad for strategic planning and to prepare the water industry for the uncertainties it faces. Water is precious and essential to life. Water supply is arguably the ultimate essential service. Australia uses about 22,000 gigalitres of water [l gigalitre (GL) = 1,000,000,000 litres, approximately 444 Olympic swimming pools (ABS 2004)] per annum across all sectors, irrigation, industry and domestic. The aim of this study was to determine the critical issues for the future of the Australian urban water supply industry. The study achieved this with the aid of scenarios that tell stories about urban water supply to the year 2025. A key to this study is the concept of organisations as living organisms, which are capable of learning and adapting to changes in their business environment. Today's business environment is constantly changing through globalisation, technological innovation and society's values. To survive, organisations must be able to anticipate and adapt to this often uncertain environment.
Traditional methods, from a mechanistic perspective, of developing strategic plans for the future have a poor track record because they invariably rely on forecasting and predicting the future from historical information that, in an increasingly uncertain and fast changing world, may no longer be appropriate. Scenarios are stories about the future. They combine uncertainty and trends with creativity, insight and intuition to enable an organisation to learn and develop strategies for the future from an organic perspective. Scenarios are not predictions, but they are plausible stories about the future. The stories do allow an organisation to re-perceive a different world by questioning prevailing paradigms and assumptions. The underlying philosophical basis for scenario planning is constructivist which is consistent with the ontological position taken for this study. This study was undertaken under a qualitative research paradigm. The ontological position taken to answer the research question was constructivist with a critical perspective where realities are intangible mental constructs based on the culture and experience of individuals or groups. Constructs are more or less informed and changeable. From an epistemological perspective the constructivist position assumes that the enquirer and subject of the research are interactively linked so that findings are created. Research under a constructivist paradigm requires a hermeneutical and dialectical methodology leading to interpretation.
The methodology adopted for this study was grounded research, being a modification of grounded theory and applicable to the business environment. Data were initially gathered by semi-structured interview, the objective being two fold. 1. The data were used to elicit critical issues for the future of the Australian urban water supply industry. 2. The data were used to develop 'plausible' futures for the urban water supply industry in the form of scenarios. The data were analysed using grounded research principles and organised using NVivo (Richards 1999; NVivo 2002). After two stages of analysis, 16 major categories, focusing on the future emerged from the data. In order to write the scenarios two key uncertainties critical to the future of the urban water supply industry were required for the scenario matrix. The two selected were 'Water availability' and 'Technological change' from the water industry's contextual environment. These two key uncertainties were considered to be the most uncertain and have the greatest impact on the future of the water industry. These two key uncertainties formed the context for the scenarios into which over 200 other issues were de-dimentionalised, as in the scenario planning method, and crafted into four scenarios. A time horizon of 2025 was selected for the scenarios to reflect the water industry's long term planning horizon.
The scenarios were called 'Decadent water use', which depicts a future where there is plenty of water and technology addresses the cost of service delivery; 'Smart water world', which depicts a future where water is scarce but is addressed by technology providing alternative sources of water; 'Muddy waters', which depicts a future where there is plenty of water but technology does not address the cost of delivery and issues of infrastructure deterioration and 'Mad Max water world', which depicts a future where water is scarce and technology does not address the scarcity, the situation becomes a crisis. From the scenarios and using concepts from complex adaptive systems theory a number of critical issues emerged from the data. Some were at a philosophical level such as whether water, as a common good, fits with society's philosophy about water. Others were at a practical level for example expressing the criticality for the water industry to build community trust and support. The research notes the potential for further qualitative research in the fields of community attitudes and behaviours towards water, water services, recycling wastewater and the preparedness to pay for water services. In addition there is potential to further develop scenarios presented in this study; 'Decadent water use', 'Smart water world', 'Muddy waters' and 'Mad Max water world'; for the Australian urban water supply industry using the data from this research as a basis for group consultation.

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Martinez, Jonathan Justen de La Vega. "Otimização estocástica na programação de bombas em redes de abastecimento urbano". Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/3828.

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Made available in DSpace on 2016-06-02T19:53:32Z (GMT). No. of bitstreams: 1 MARTINEZ_Jonathan_2014.pdf: 11989383 bytes, checksum: 96fb53d9544014ea55b1e53ee779c134 (MD5) Previous issue date: 2014-03-14
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This study presents a pump scheduling problem for the capture, transfer and storage of water supply systems in urban networks, whose objective is to minimize the electricity cost associated to the pumping operations. To deal with the dynamic and random nature of the water-demand, we propose two-stage stochastic programming with recourse models, where the random variables are represented by a finite and discrete set of realizations or scenarios. The developed mathematical models are extensions of previous deterministic models of the literature and they reflect the basic assumption that a fixed cost could be incurred by the turn on/ turn off activities of the hydraulic pumps. In order to control violations of the water-demand constraints in the presence of multiple different scenarios, we also consider a robustness technique in an attempt to obtain almost feasible solutions. Last, but not least, we adopt a risk-aversion criteria so-called mean absolute deviation to obtain second-stage costs less dependent on the realizations of the scenarios. The scenarios were generated according to a Monte-Carlo simulation procedure that may use any probability distributions to produce the empirical probabilities of the random variables. As the proposed pump scheduling problem with fixed cost is a two-stage stochastic mixed 0 − 1 program, we develop a efficient hybrid heuristic to obtain good-quality solutions of practical instances in a plausible running time. Overall results evidence the stability of the scenario generation method, the sensitivity of the solution according to the key parameters of the mathematical model, and the efficiency of the heuristic in solving large instances. Finally, we show that is possible to save resources by solving the stochastic programming model instead of adopting simpler approaches based on the expected value.
Esse estudo apresenta um problema de programação de bombas para a captação, armazenamento e transferência de água em sistemas de abastecimentos de água em redes urbanas, cujo objetivo é minimizar o custo de energia elétrica associado às operações de bombeamento. Para lidar com a natureza dinâmica e aleatória da demanda por água, foram propostos modelos de programação estocástica de dois estágios com recurso, em que a variável aleatória é representada por um conjunto finito de realizações ou cenários. Os modelos matemáticos desenvolvidos são extensões de modelos determinísticos da literatura e refletem a suposição básica de que é possível se incorrer em um custo fixo pelas atividades de liga/desliga das bombas hidráulicas. Para controlar as violações das restrições de demanda por água na presença de múltiplos cenários diferentes, considerou-se também uma técnica de robustez na tentativa de gerar soluções quase factíveis. Por último, mas não menos importante, adotou-se um critério de aversão ao risco denominado desvio médio absoluto para obter custos de segundo estágio menos dependentes das realizações dos cenários. Os cenários foram gerados de acordo com um procedimento baseado em simulação Monte-Carlo que pode utilizar qualquer distribuição de probabilidade para produzir as probabilidades empíricas das variáveis aleatórias. Como o problema de programação de bombas com custo fixo proposto é um programa inteiro misto 0−1 estocástico, desenvolve-se uma heurística híbrida eficiente para obter soluções de boa qualidade de instâncias práticas em um tempo computacional plausível. Os resultados evidenciam a estabilidade do método de geração de cenários, a sensibilidade da solução de acordo com parâmetros-chave do modelo matemático, e a eficiência da heurística na resolução de instâncias de grande porte. Finalmente, foi demonstrado que é possível poupar recursos pela resolução do modelo de programação estocástica, em vez de adotar abordagens mais simples baseadas no valor esperado.

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46

Akbar, H. M. Delwar. "Accessibility of the urban water supply to the poor in developing countries : the case of Dhaka, Bangladesh /". [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18725.pdf.

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47

au, mike mouritz@dpi wa gov, e Mike Mouritz. "Sustainable urban water systems : policy and professional praxis". Murdoch University, 1996. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20051109.95558.

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The provision of water, wastewater and stormwater infrastructure is an essential ingredient of cities. However, questions are being raised about the type and form of urban infrastructure, for economic and environmental reasons. Traditionally these techologies have offered linear solutions, drawing increasing volumes of water into cities and discharging waste at ever increasing levels, causing escalating stress on the environment. In addition the costs of water infrastructure provision and replacement, both in the developing and developed world, is becoming prohibitive. In response, a new paradigm has been called for and new solutions are emerging that have been labelled as Integrated Urban Water Management (IUWM). This concept can be considered to consist of both technical and philosophical dimensions, and represents a new form of professional praxis. However, the adoption of these techniques and concepts is constrained by the inertia of the existing urban water systems. It is therefore argued that the introduction of any change must occur across a number of dimensions of the technoeconomic system of the city. These dimensions-artefacts and technical systems (i.e. the technology and knowledge systems), professional praxis and socio-political context (i.e. institutions, culture and politics) and biophysical realities and world views (i.e. the environment and underlying values) - provide a framework for analysis of the change process - both how it is occurring and how it needs to occur. This framework is used to illustrate the link between environment values and the process of technological innovation, and points to the need for the emerging values and innovations to be institutionalised into the professional praxis and socio-political context of society. Specifically, it is argued that a new form of transdisciplinary professional praxis is emerging and needs to be cultivated. A broad review of the literature, an evaluation of selected emerging technologies and three case studies are used to illustrate and argue this position. These examples show the potential economic, social and environmental benefits of IUWM and provide some insight into the potential which this approach has to influence the form and structure of the city and at the same time highlighting the institutional arrangements required to manage urban water systems.

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48

Flower, David Jonathan Mark. "An integrated approach to modelling urban water systems". Monash University. Faculty of Engineering. Department of Civil Engineering, 2009. http://arrow.monash.edu.au/hdl/1959.1/73160.

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The energy consumption and greenhouse gas (GHG) emissions associated with urban water systems have come under scrutiny in recent times, as a result of increasing interest in climate change, to which urban water systems are particularly vulnerable. The approach most commonly taken previously to modelling these results has been to consider various urban water system components in great detail, but in isolation from the rest of the system. This piecewise approach is suboptimal, since it systematically fails to reveal the relative importance of the energy consumption and GHG emissions associated with each system component in the context of the entire urban water system. Hence, it was determined that a new approach to modelling the energy consumption and GHG emissions associated with urban water systems was necessary. It was further determined that the value derived from such a model would be greatly enhanced if it could also model the water consumption and wastewater generation associated with each system component, such that integrated policies could be developed, aimed at minimising water consumption, wastewater generation, energy consumption and GHG emissions concurrently. Hence, the following research question was posed: How should the relationships between the water consumption, wastewater generation, energy consumption and GHG emissions associated with the operation of urban water systems be modelled such that the impact of various changes to the system configuration made at different spatial scales can be determined within the context of the entire system? In this research project, life cycle assessment ideas were employed to develop such a new modelling methodology. Initially, the approach was developed at the building-scale, such that the end uses of water present in a selected building and any associated appliances could be modelled, along with the fraction of the citywide water supply and wastewater systems directly associated with providing services to that building. This vast breadth of scope was delivered by considering only the operational life cycle stage of each urban water system component, excluding both the pre- and post-operational life cycle stages of the associated infrastructure. The value of this pilot model was illustrated by several case studies, focused on residential buildings connected to the centralised water supply and wastewater systems in Melbourne, Australia. Later, the approach was extended to the city-scale by using probabilistic distributions of each input parameter, such that all of the end uses of water present in a city, and all of the associated building-scale appliances could be modelled, along with the associated complete water supply and wastewater systems. The value of this city-scale model was illustrated by applying it to model a hypothetical case study city, resembling Melbourne, Australia in many ways. Due to a lack of data, this application was limited to the residential sector of the case study city, along with the fraction of the citywide water supply and wastewater systems directly associated with providing services to that sector. The results generated by the pilot and city-scale models showed that the new modelling methodology could be employed at a wide range of scales to assess the relative importance of each modelled urban water system component in terms of the specified results. Importantly, the high resolution of those results enabled the identification of the underlying causes of the relative importance of each urban water system component, such that efficient and effective approaches to reducing each result for each system component could be developed. Interestingly, for the specific case studies investigated, it was revealed that some commonly neglected system components were actually extremely important, such as domestic hot water services, a trend found to be largely driven by hot water consumption in showers.

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49

Creese, Edward E. "Urban water systems, demand management and sustainable development". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0024/NQ51186.pdf.

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50

Mouritz, Michael John. "Sustainable urban water systems: Policy and professional praxis". Thesis, Mouritz, Michael John (1996) Sustainable urban water systems: Policy and professional praxis. PhD thesis, Murdoch University, 1996. https://researchrepository.murdoch.edu.au/id/eprint/211/.

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Abstract (sommario):

The provision of water, wastewater and stormwater infrastructure is an essential ingredient of cities. However, questions are being raised about the type and form of urban infrastructure, for economic and environmental reasons. Traditionally these techologies have offered linear solutions, drawing increasing volumes of water into cities and discharging waste at ever increasing levels, causing escalating stress on the environment. In addition the costs of water infrastructure provision and replacement, both in the developing and developed world, is becoming prohibitive. In response, a new paradigm has been called for and new solutions are emerging that have been labelled as Integrated Urban Water Management (IUWM). This concept can be considered to consist of both technical and philosophical dimensions, and represents a new form of professional praxis. However, the adoption of these techniques and concepts is constrained by the inertia of the existing urban water systems. It is therefore argued that the introduction of any change must occur across a number of dimensions of the technoeconomic system of the city. These dimensions-artefacts and technical systems (i.e. the technology and knowledge systems), professional praxis and socio-political context (i.e. institutions, culture and politics) and biophysical realities and world views (i.e. the environment and underlying values) - provide a framework for analysis of the change process - both how it is occurring and how it needs to occur. This framework is used to illustrate the link between environment values and the process of technological innovation, and points to the need for the emerging values and innovations to be institutionalised into the professional praxis and socio-political context of society. Specifically, it is argued that a new form of transdisciplinary professional praxis is emerging and needs to be cultivated. A broad review of the literature, an evaluation of selected emerging technologies and three case studies are used to illustrate and argue this position. These examples show the potential economic, social and environmental benefits of IUWM and provide some insight into the potential which this approach has to influence the form and structure of the city and at the same time highlighting the institutional arrangements required to manage urban water systems.

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