Tesi sul tema "Biological assessment of water supply"

The utilisation of rainwater tanks and bore wells are very common in many parts of rural Australia and Papua New Guinea. In Australia, on-site collection and storage of potable water for domestic use is carried out by approximately 30.4 percent of the rural population while 90% of the population in Papua New Guinea access water from on-site collection and storage of potable water. Few studies have monitored the quality of such water supplies on a seasonal and event associated basis. The aim of this study was to evaluate the microbiological and physio-chemical properties of the on-site domestic water supply systems and various factors that may influence characteristics of the water. It aimed to evaluate the relationship of microbiological and physio-chemical characteristics in the water supply systems. 14 rainwater tanks, 4 bore well and 10 reticulated water supply sites in Hawkesbury District, NSW Australia were investigated. Characteristics of the sites physical situation and natural environmental condition were considered to be similar to on-site water supply situations in Papua New Guinea. The results and techniques of the study will be used as a model in Papua New Guinea in the assessment of water quality issues. As the study showed that the quality of water in rainwater tanks was below WHO guideline recommendations on numerous instances, it was proposed that water treatment and maintaining the cleanliness of roof catchments, gutters and tanks should be addressed for domestic use systems. A protocol for sampling, assessment and data interpretation of faecal indicator bacteria populations in domestic catchment supply systems was developed and demonstrated
Master of Science (Hons)

The utilisation of rainwater tanks and bore wells are very common in many parts of rural Australia and Papua New Guinea. In Australia, on-site collection and storage of potable water for domestic use is carried out by approximately 30.4 percent of the rural population while 90% of the population in Papua New Guinea access water from on-site collection and storage of potable water. Few studies have monitored the quality of such water supplies on a seasonal and event associated basis. The aim of this study was to evaluate the microbiological and physio-chemical properties of the on-site domestic water supply systems and various factors that may influence characteristics of the water. It aimed to evaluate the relationship of microbiological and physio-chemical characteristics in the water supply systems. 14 rainwater tanks, 4 bore well and 10 reticulated water supply sites in Hawkesbury District, NSW Australia were investigated. Characteristics of the sites physical situation and natural environmental condition were considered to be similar to on-site water supply situations in Papua New Guinea. The results and techniques of the study will be used as a model in Papua New Guinea in the assessment of water quality issues. As the study showed that the quality of water in rainwater tanks was below WHO guideline recommendations on numerous instances, it was proposed that water treatment and maintaining the cleanliness of roof catchments, gutters and tanks should be addressed for domestic use systems. A protocol for sampling, assessment and data interpretation of faecal indicator bacteria populations in domestic catchment supply systems was developed and demonstrated

Thesis (M. Sc.) (Hons) -- University of Western Sydney, 2003.
"A thesis submitted in partial fulfilment of the requirements for the degree of Master of Science (Hons.), University of Western Sydney, Australia, Water Research Laboratory, Centre for Water & Environmental Technology." Includes bibliography : leaves 168 - 183 and appendices.

Thesis (MScEng)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: The increased water demand to be supplied by municipal water distribution systems, and subsequent increased storage period of reserve water, may have implications with regards to water ageing and subsequently may have an impact on health and safety. Current master planning design standards could have a negative effect on water residence time. The decay of the disinfectant potential is a function of the residence time in the distribution system. The objective of this study is to identify and measure existing systems to optimally increase water quality in a distribution system while supplying an increase in demand, dealing with the deterioration of pipe infrastructure and the introduction of alternative water sources. To do this, one must understand the dynamics of water networks and the parameters that affect water quality. The foundation of a water quality model is based on the construction of an accurate hydraulic model. To identify and measure these systems, one must understand the aspects of water purification and the techniques used to achieve water standards in a distribution system. These techniques and standards play a huge role in the prediction of water quality. In this paper the fundamentals and techniques used to determine and measure such a model are discussed. Consequently, additional design parameters to assess water quality must be incorporated into current master planning practice to optimally design water networks. These models are used to determine the appropriate levels of disinfectant at strategic locations in a system. To illustrate these design parameters and systems currently used in practice, a case study involving Umgeni Water (UW) and EThekwini municipality (EWS) was used to determine the most suitable disinfectant strategy for a municipality’s distribution system. Future scenarios and the impact of disinfectant mixing and increased residence time of the water in the system were also determined. The use of this water quality model in a distribution system will ultimately provide a sustainable platform for a risk monitoring procedure.
AFRIKAANSE OPSOMMING: Die verhoogde aanvraag na water in munisipale voorsieningstelsels, en die daaropvolgende verhoogde stoortydperk van reserwe water, kan implikasies inhou met betrekking tot water veroudering waarna dit ‘n impak op gesondheid en veiligheid kan hê. Huidige meesterbeplanning ontwerpstandaarde kan 'n noemenswaardige uitwerking op water retensietyd hê, veral omdat chloor se vervaltyd op sy beurt 'n funksie van water retensietyd is. Die doel van hierdie studie is om 'n prosedure te identifiseer om watergehalte optimaal te verhoog in 'n waterverspreidingstelsel, terwyl die toename in water aanvraag voortduur. Om dit te kan doen moet die dinamika van water netwerke en die parameters wat die gehalte van water beïnvloed, bestudeer word. Die opstel van 'n waterkwaliteit model is gebaseer op die bou van 'n akkurate hidrouliese model. Om uiteindelik die ontwerp van 'n waterkwaliteit oplossing suksevol uit te voer, moet 'n mens al die aspekte van watersuiwering en die tegnieke wat gebruik word om waterstandaarde te handhaaf in 'n verspreidingstelsel verstaan. In hierdie verslag word die beginsels en tegnieke wat gebruik word om so 'n model op te stel, bespreek. Bykomende waterkwaliteit ontwerpparameters moet by huidige meesterbeplanning gevoeg word om waternetwerke optimaal te ontwerp. Hierdie modelle word gebruik om die geskikte vlakke van ontsmettingsmiddel op strategiese plekke in 'n stelsel te bepaal. 'n Gevallestudie van Umgeni Water (UW) en eThekwini-munisipaliteit (EWS) is gebruik om die mees geskikte ontsmettingsmiddel strategie vir 'n munisipaliteit se verspreiding te illustreer. Toekomstige scenario's en die impak van ontsmettingsmiddelvermenging en verhoogde retensietyd van die water in die stelsel sal ook bepaal kan word. Die gebruik van hierdie gehalte-watermodel in 'n verspreidingstelsel sal uiteindelik 'n volhoubare platform vir 'n risiko moniteringstelsel inhou.

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.

Of the factors that determine development potential in a given geographic area, the availability of water for residential, commercial, and industrial purposes is a primary indication of prospective growth. Governmental bodies at the regional, state and federal levels often need to identify water supply availability in order to identify growth potential. To address this need, a procedure for the preliminary assessment of water supply availability has been developed that can potentially be applied to any geographic area in the United States. The procedure uses the USGS demand cataloging unit as the basic planning area, with supply estimates from streamflow parameters at USGS gage locations and demand estimates from USGS demand reports. By comparing known supply and demand estimates in a base year, an overview of water supply availability in the region can be determined. With supply and demand data in a base year, projections of future water supply availability can then be made. Detailed projection of future water demand must account for changes in the amount of water use activities and the rates of water use within those activities, but a simplified procedure is applied here. Total offstream water use is averaged over the population in the base year to determine per-capita offstream use, which is assumed to remain constant in the future in this preliminary assessment procedure. Population is then projected and demand is forecast as a function of the projected population. The supply quantity is projected assuming each flow parameter derived from the historical record will remain constant in the future year. By comparing projected supply and demand estimates, water supply availability in future years can be anticipated in the planning area.
Master of Science

S'espera que la sostenibilitat de les xarxes de subministrament d'aigua sigui un tema important en un futur pròxim a causa de la falta d'accés a l'aigua en àrees específiques, al creixement de les ciutats i a la renovació de xarxes velles. En aquest sentit, analitzar a nivell ambiental aquest sistema és clau per planificar futures xarxes, la qual cosa pot prevenir impactes ambientals significatius. A més, l'eficiència en l'ús de l'aigua a les ciutats és una altra qüestió important i cal analitzar els nous usos urbans de l'aigua, com l'agricultura. Aquest és el cas de l'agricultura vertical, que consisteix en la integració de sistemes agrícoles en edificis. Tot i que aquests sistemes de producció d'aliments urbans poden augmentar la demanda d'aigua a les ciutats, representen una oportunitat per reduir el consum i el transport d'aigua relacionats amb l'agricultura a nivell regional. Investigacions prèvies sobre xarxes d'abastament d'aigua es centren en analitzar estudis de casos específics a nivell municipal o regional, mostrant resultats molt diferents. Per tant, es requereix una avaluació integral del sistema des d'una perspectiva general per entendre quins són els factors clau que afecten els impactes ambientals de les xarxes. A escala edifici, la millora de l'eficiència en l'ús de l'aigua pot prevenir impactes ambientals significatius al llarg del cicle urbà de l'aigua, especialment per a nous usos de l'aigua com l'agricultura vertical. En aquest context, estudis anteriors han discutit el potencial d'aquests sistemes o implementat anàlisis basades en dades teòriques. No obstant això, encara falta manca avaluar cultius realitzats en un casos d’estudi reals. Aquesta tesi té com a objectiu aprofundir en aquestes àrees de coneixement analitzant el sistema urbà des de l'escala ciutat a alternatives locals específiques i busca respondre a les següents preguntes: (i) Quins són els principals factors que afecten els impactes ambientals de les xarxes d'abastament d'aigua a les ciutats i quines millores s'han d'implementar? - Escala ciutat (ii) Com d'eficaces són les tecnologies per a l'estalvi de l'aigua utilitzades a nivell d'edifici en les zones urbanes? - Escala edifici (iii) Els hivernacles integrats en coberta són una alternativa eficient i sostenible per a la producció d'aliments a les ciutats? - Alternativa específica Aquesta tesi contribueix a un major enteniment dels principals factors que influeixen en els impactes de les xarxes d'abastament d'aigua i aporta eines útils per a l'anàlisi ambiental d'aquests sistemes. Els planificadors urbans i els gestors de xarxes poden utilitzar els resultats per planificar xarxes sostenibles. A més, la investigació experimental realitzada en edificis innovadors amb tecnologies d'estalvi d'aigua i agricultura vertical demostra la viabilitat d'aquests sistemes avançats i destaca la importància d'optimitzar l'ús dels recursos. Investigacions futures en aquestes àrees de coneixement podrien centrar-se en els següents temes: • Avaluar l'ecoeficiència de la construcció de xarxes d'abastament d'aigua. • Implementació d'estudis estadístics addicionals sobre el funcionament de les xarxes d'abastament d'aigua. • Desenvolupar nous sistemes urbans que implementin el nexe aigua-energia-aliments per integrar la producció d'aliments i els problemes d'eficiència en l'ús de l'aigua. • Explorar tot el potencial dels i-RTGs i analitzar el sistema que conrea diferents cultius.
Se espera que la sostenibilidad de las redes de suministro de agua sea un tema importante en un futuro próximo debido a la falta de acceso al agua en áreas específicas, al crecimiento de las ciudades y a la renovación de viejas redes. En este sentido, analizar a nivel ambiental este sistema es clave para planificar futuras redes, lo cual puede prevenir impactos ambientales significativos. Además, la eficiencia en el uso del agua en las ciudades es otra cuestión importante y es necesario analizar los nuevos usos urbanos del agua, como la agricultura. Este es el caso de la agricultura vertical, que consiste en la integración de sistemas agrícolas en edificios. Aunque estos sistemas de producción de alimentos urbanos pueden aumentar la demanda de agua en las ciudades, representan una oportunidad para reducir el consumo y el transporte de agua relacionados con la agricultura a nivel regional. Investigaciones previas sobre redes de abastecimiento de agua se centran en analizar estudios de casos específicos a nivel municipal o regional, mostrando resultados muy diferentes. Por lo tanto, se requiere una evaluación integral del sistema desde una perspectiva general para entender cuáles son los factores clave que afectan a los impactos ambientales de las redes. A escala edificio, la mejora de la eficiencia en el uso del agua puede prevenir impactos ambientales significativos a lo largo del ciclo urbano del agua, especialmente para nuevos usos del agua como la agricultura vertical. En este contexto, estudios anteriores han discutido el potencial de estos sistemas o implementado análisis basados en datos teóricos. Sin embargo, todavía falta una evaluación de cultivos realizados en un caso de estudio real. Esta tesis tiene como objetivo profundizar en estas áreas de conocimiento analizando el sistema urbano desde la escala ciudad a alternativas locales específicas y busca responder a las siguientes preguntas: (i) ¿Cuáles son los principales factores que afectan a los impactos ambientales de las redes de abastecimiento de agua en las ciudades y qué mejoras deben implementarse? - Escala ciudad (ii) ¿Cómo de eficaces son las tecnologías para el ahorro del agua utilizadas a nivel de edificios en las zonas urbanas? - Escala edificio (iii) ¿Los invernaderos integrados en cubierta son una alternativa eficiente y sostenible para la producción de alimentos en las ciudades? – Alternativa específica Esta tesis contribuye a un major entendimiento de los principales factores que influyen en los impactos de las redes de abastecimiento de agua y aporta herramientas útiles para el análisis ambiental de estos sistemas. Los planificadores urbanos y los administradores de redes pueden utilizar los resultados para planificar redes sostenibles. Además, la investigación experimental realizada en edificios innovadores con tecnologías de ahorro de agua y agricultura vertical demuestra la viabilidad de estos sistemas avanzados y destaca la importancia de optimizar el uso de los recursos. Investigaciones futuras en estas áreas de conocimiento podrían centrarse en los siguientes temas: • Evaluar la ecoeficiencia de la construcción de redes de abastecimiento de agua. • Implementación de estudios estadísticos adicionales sobre el funcionamiento de las redes de abastecimiento de agua. • Desarrollar nuevos sistemas urbanos que implementen el nexo agua-energía-alimento para integrar la producción de alimentos y los problemas de eficiencia en el uso del agua. Explorar todo el potencial de los i-RTGs y analizar el sistema que cultiva diferentes cultivos.
The sustainability of water supply networks is expected to be a major issue in the near future due to the lack of access to water in specific areas, the growth of cities and the refurbishment of old networks. In this sense, analysing the environmental performance of this system is key to planning future networks—this can prevent significant environmental impacts. Moreover, water use efficiency in cities is another important issue and new urban uses for water, such as agriculture, need to be analysed. This is the case for vertical farming, which consists of the integration of agricultural systems in buildings. Although these urban food production systems can increase the demand for water in cities, they represent an opportunity to reduce the water consumption and transport related to agriculture at the regional level. Previous research on water supply networks focus on analysing specific case studies at municipal or regional level, showing very different results. Thus, a comprehensive assessment of the system from a general perspective is required to understand which are the key factors affecting its environmental impacts. At the building scale, improving water efficiency can prevent significant environmental impacts along the urban water cycle, especially for new water uses such as vertical farming. In this context, previous studies have discussed the potential of these systems or implemented analysis based on theoretical data. However, the assessment of crops conducted in a real case study is still lacking. This dissertation aims at contributing to understand more deeply these research fields, analysing urban areas from the city level to specific alternatives at the building level, and seeks to answer the following questions: (i) What are the main factors affecting the environmental impacts of water supply networks in cities and which improvements should be implemented? – city scale (ii) How effective are water-saving technologies used at the building level in urban areas? – building scale (iii) Are integrated rooftop greenhouses an efficient and sustainable alternative for food production in cities? – Specific alternative This dissertation contributes to understand the main factors influencing the impacts of water supply networks and provides useful tools for the environmental analysis of these systems. The results can be used by urban planners and network managers to planning sustainable networks. Moreover, the experimental research conducted in innovative buildings with water-saving technologies and vertical farming proves the feasibility of these advanced systems and highlights the importance of optimising the use of resources. Future research on the fields assessed might focus on the following areas: • Evaluating the ecoefficiency of the construction of water supply networks. • Implementing further statistical studies of the operation of water supply networks. • To implement the water-energy-food nexus to develop new urban systems that integrate food production and water use efficiency issues. • Exploring the full potential of i-RTGs and analyse the system growing different crops.

This project describes a methodology for developing a digitized GIS-based inventory of underground municipal utilities, and recommends an approach for developing a database, which will assist with considerably improved management of buried systems and effective use of limited available resources. The study also discusses the water and sewer infrastructure debt and the total infrastructure debt in Canada. Some other issues related to the Canadian water infrastructure, such as water pricing and consumption patterns, along with the deterioration mechanisms of the underground services, are also discussed. The study focuses on the main services of water supply and sewage systems in any Canadian municipality, which presently are in an advanced state of deterioration. The steps required to develop such an inventory are reviewed and suggestions are made for condition assessment of the system using non-destructive techniques, employing simple methods, as well as more sophisticated tests in critical sectors, where further investigation is required. These methods are also summarily revised.
The underground infrastructure of the McGill Downtown Campus is summarily described; it comprises the various underground features which exist in a small community, e.g. water-supply and sewage system, electrical lines, gas pipelines, telecommunication networks, etc., which are similar with Montreal's underground services, in terms of age, materials employed, workmanship and technologies available over the past 175 to 200 years. The framework for the underground infrastructure inventory is proposed for implementation in a small community such as the McGill Downtown Campus.
The long-term goal of the project is to extrapolate the McGill "model", and to enhance it such that the municipalities in Canada can implement it as a basis for development of GIS-based inventories and condition assessment, and prioritization for effective management of underground services, which include scheduling, financing and implementation of repair, rehabilitation and replacement of underground and other infrastructure.

Karst springs are an essential source of private water supply in northeast Tennessee for various end-users. There are no regulatory standards for private (drinking) water quality in the state, unlike the public water system, while water users are only advised to test for contaminants in private water sources like springs or private wells. Water quality generally is spatially and temporally dynamic in terms of chemical quality, and more prominently in a karst environment, therefore, this study investigates the water quality of roadside springs used for drinking water. Parameters to be measured include E. coli, radon, and various physicochemical properties (pH, conductivity, dissolved oxygen, chloride, fluoride, sulfide, nitrite, and nitrate). I plan to collect 51 water samples from 51 spring locations so that spatial patterns in spring water quality can be evaluated using spatial interpolation, statistical correlation, or spatial regression. Spring water quality results will be compared to water quality of the streams into which these springs discharge. Preliminary work to be presented here includes identification of sampling sites and sampling strategies and integration of existing data, including geology and spring water quality data from a prior related study. Key findings will guide the delineation of the studied karst springs into risk regions for microbial, chemical, and radioactive content, and identification of key factors associated with high risk regions.

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.

Over the last couple of decades, a significant amount of research has been carried out on rural water supplies in developing countries, and have identified the fact that the communal water supply model is not sustainable everywhere, especially in sparsely populated rural areas; factors obstructing sustainability include lack of spare parts, management systems and private/public capacity. Despite their enormous contribution to the water sector, the extant studies stay within the subsidized communal water supply and capacity building, post construction support or management system. In other words, very few studies have been done into household (private) level water supply. The Self Supply model is an approach which provides support to households/communities to complement their efforts and accelerate sustainable access to safe water incrementally through improvement to traditional water sources (hand dug wells) by putting in their own investment. The Self Supply model may give significant benefits for sustainable safe water supplies, especially in sparsely populated rural areas, in comparison with the communal water supply though to date there has been little monitoring and systematic analysis of what impact these changes have made at the grassroots level. The standpoint of this study is pragmatic, and herein, mixing quantitative and qualitative methods was justified in order to design the research methodologies. The research was conducted in the Luapula Province of Zambia using a concurrent triangulation strategy to offset the weakness inherent within one method with the strengths of the other. The data was collected through inventory and sanitary surveys, water quality testing, household surveys, document analyses, focus group discussions and key informant interviews to determine the most appropriate water supply model for safe, accessible, sustainable, cost-effective and acceptable water supplies for households in sparsely populated rural areas of Zambia. The principal argument of this study is that reliance only on a communal water supply model limits the achievement of increased sustainable access to a safe water supply; hence a Self Supply model is needed which does not compete with the communal models but works alongside them in sparsely populated rural areas of developing countries for the purpose of increasing access and achieving sustainability. It was strongly defended by the overall findings that a Self Supply model could significantly reduce the faecal contamination risk in water quality and deliver a higher per capita water use and better convenience of access than the communal model; however its reliability with respect to the water source drying up needs to be monitored. Further, this does not mean that the communal model is not sustainable anywhere, rather that it is important to build blocks for a sustainable environment to access safe water in a symbiotic way between the communal and Self Supply models under the condition that the government and NGOs/external support agencies overcome the temptation to provide a water supply to rural dwellers as a giveaway social service.

A certain amount of water is required for a mine site located in Turgutlu in Western Turkey to be used in mining processes. The purpose of this study is to assess the impacts associated with meeting water supply requirements for the mine. Scope of the study involves determination of the alternative water resources, the assessment of impacts associated with each resource and the selection of the most feasible alternative in the aspect of environmental and technical effects. Three alternatives suggested to supply mine process water are surface water, groundwater and reuse of waste water of Turgutlu town after treatment. A low flow analysis of Gediz River was conducted for the evaluation of the surface water. For the groundwater alternative, Turgutlu-Salihli aquifer model was established using MODFLOW 2009.1 software and the impacts on groundwater resources were evaluated. The evaluation of the last alternative, reuse of waste water of Turgutlu after treatment, was based upon the amount of waste water generated and treatment needed. Results of the alternatives show that each alternative is applicable to supply the required water to the mine site. However, the storage of the Gediz River water in a v small dam in wet seasons to be used later in dry seasons and the reuse of waste water of Turgutlu after treatment are the alternatives with least impacts on existing water users and related ecosystems.

Les services de distribution d’eau utilisent différentes ressources (eaux de surface et eaux souterraines), y compris une utilisation accrue de ressources alternatives (eau dessalée, eau réutilisée, transferts d'eau entre bassins) pour alimenter les différents utilisateurs (domestiques, agricoles, industriels, etc.). La combinaison de ces ressources en eau avec des technologies (incluant infrastructures, fonctionnement et énergie) donne lieu à une combinaison régionale d'approvisionnement en eau (WSmix) pour chaque utilisation spécifique. Actuellement, les bases de données existantes d'inventaire du cycle de vie (ICV) utilisées en Analyse du Cycle de Vie (ACV) ne proposent pas ce type de données relative aux WSmix régionalisées pour modéliser des processus. Ceci conduit à une représentation médiocre des systèmes d'approvisionnement en eau et des impacts environnementaux associés. Pour combler cette lacune, cette thèse développe (i) un cadre conceptuel cohérent de mix d'approvisionnement en eau (WSmix) pour la mise en oeuvre en ACV, (ii) une base de données opérationnelle incluant le mix de ressource en eau pour différents utilisateurs à l'échelle mondiale adossée à une matrice dite « technologique » associant chaque ressource à des technologies de production d'eau. Afin de tester en ACV l'opérationnalisation et l'applicabilité du mix WSmix à l'échelle mondiale et pour différents utilisateurs, le concept de WSmix est appliqué à deux exemples contrastés: un service (fourniture d’un m3 d’eau publique à la porte de l’utilisateur) et un produit global (production d’un kg maïs). Enfin, pour évaluer dans quelle mesure le WSmix sera affecté par les changements climatiques et socio-économiques, cette thèse propose le développement d'un WSmix Prospectif (P-WSmix) pour une mise en oeuvre pratique dans les études d'ACV et d'empreinte sur l'eau
Water utilities draw different water sources (surface and groundwater), including increased use of alternative sources (e.g. desalinated water, reused water, inter-basin water transfers) to supply freshwater to different users (domestic, agriculture, etc.). The combination of water sources and technologies (including infrastructures and energy) results in a regional water supply mix (WSmix) for each specific use. Existing Life Cycle Inventory (LCI) databases used in Life Cycle Assessment (LCA), do not include these mixes when modelling processes, leading to a poor representation of water supply systems and related environmental impacts. To fill this gap, this thesis developes 1) consistent water supply mix (WSmix) model for implementation in LCA, 2) a first database of water source mixes for different users at a global scale and a technological matrix linking water sources to water production technologies in order to operationalize the practical implementation of the WSmix in LCA studies. In order to test the operationalization and applicability of the WSmix at worldwide scale and for different users, this theseis also describes the operationalization and application of the WSmix for two different water users worldwide with two different approaches: providing a generic service (public water supply) and producing a global product (maize production). Finally, to evaluate to what extent the WSmix will be affected by climate and socio-economic changes in the future, this thesis describes the development of a Prospective WSmix (P-WSmix) for practical implementation in LCA and water footprint studies

With numerous bioassessment methodologies available, a regional protocol needs to be developed to ensure that results are comparable. A regional assessment protocol was developed that includes collecting five benthic macroinvertebrate samples, identifying organisms to genus, and calculating the following metrics: Number of Taxa, Total Number of Individuals, Simpson's Diversity Index, Shannon's Diversity Index, Percent Contribution of Dominant Taxa, Hilsenhoffs Biotic Index, and Percent Contribution of Dipterans. Once the protocol was developed, it was used to assess the Bayou Chico tributaries and watershed. All three tributaries had been significantly impacted by human activity as had the watershed as a whole. This study indicates that a regional protocol could be developed and is appropriate for biomonitoring at the watershed scale.

Lead (Pb) is a known toxicant that affects young children. It is believed that old water reticulation systems are prone to lead leaching from the walls of lead pipes and fixtures where water is conveyed to households. Many households in Christchurch city particularly in the Northwestern and Central parts of the city contain old water reticulation systems thereby, putting children at considerable health risks. The purpose of this dissertation is to identify the hazards of lead exposure that comes from old water reticulation system of Northwest (NW) Christchurch water supply to households, characterize the health risks due to such contamination and, finally, to suggest possible ways to minimize the hazards. This is accomplished by conducting a systematic review of literature on the exposure patterns of lead from reticulation systems and a literature review of the possible dose response patterns of health effects of lead contamination from old water reticulation systems on children. Thus, this dissertation involves a literature based risk assessment of lead contamination of drinking water supply in the Northwest Christchurch Zone and particularly, its effects on young children. The selection process of the research studies is based on whether they offer accurate and suitable information on the risk of adverse mental function in infants and young children due to environmental lead exposure; whether the studies have been peer reviewed by qualified scientists; whether the results are confirmed by other studies; and involves only human subjects. Future research may consider whether lead levels in drinking water are seasonal; whether these values are significant to health or, the possible role of the government in tightening product controls when monitoring the availability and health risk of high lead drinking water supply plumbing products available in the New Zealand market.

Anthropogenic stressors to freshwater environments have perpetuated water quality and quantity challenges for northern communities across Arctic Canada, making drinking water resources a primary concern for Arctic populations. To understand the ecological trajectory of freshwater supply sources, we conducted a paleolimnological assessment on two supplemental sources of freshwater in Igloolik, Nunavut, Canada. A stratigraphic examination of bioindicators (Insecta: Diptera: Chironomidae) allowed for paleotemperature reconstructions with decadal and centennial resolution over the past 2000 years. Between 200 and 1900 CE, the sub-fossil chironomid community was comprised of cold-water taxa, such as Abiskomyia, Micropsectra radialis-type, and Paracladius. Reconstructed temperatures were consistent with known climate anomalies during this period. A rapid shift in the composition of the chironomid community to warm-water adapted taxa (Chironomus anthracinus-type, Dicrotendipes, and Tanytarsus lugens-type) in the late 20th century was observed in both systems. Our results demonstrate that these lake ecosystems are undergoing marked transformations to warmer, more nutrient-rich environments, and suggest water sustainability pressures on freshwater and human systems will likely continue in tandem with ongoing climate change. To contextualize the influence of recent warming and elucidate the status of water resource vulnerability over the longer term, paleolimnological methods can be usefully applied as components of vulnerability assessments.

Desalination is an integral component of water supply for many cities and regions around the globe. Although, desalination can offer a rainfall independent source of water and provide social benefits, it is energy intensive compared to conventional water sources and can have significant impacts upon the environment. Therefore an interdisciplinary approach is required when planning for water supply by desalination. A life cycle assessment of a desalination supply chain can be integrated into an optimisation framework to simultaneously consider all possible planning alternatives and find the combination of planning decisions that optimizes environmental and economic objectives. This thesis aimed to develop a desalination supply chain optimization life cycle framework to analyze the economic and environmental impacts and trade-offs for alternative planning scenarios. The framework used life cycle assessment and a levelised cost model to quantify and compare the supply chain environmental and economic impacts for a range of planning scenarios. The framework incorporated a mixed integer linear programming model to determine optimal planning decisions such as water capacity expansion of each type of desalination technology over a planning horizon, and optimal locations of new desalination plants while considering interdependencies among water distribution and treatment processes. The framework was tested for future seawater reverse osmosis desalination planning in the northern metropolitan area of Perth, Western Australia over the next 20 years. Results indicated that, a decentralised desalination supply system with small and medium-sized SWRO plants integrated into the Perth metropolitan area could achieve a lower environmental and economic impact, when compared to a centralised supply system with a large desalination plant located far from final demand. Improving seawater quality by introducing beach well intake - a mature intake technology for smaller-sized plants - could further promote the decentralised supply system environmental and economic performance. The capital expenditure contribution to total cost for the treatment facilities in the decentralised supply system was found to be higher than for the centralised supply system. However, this was outweighed by the significant water distribution pipeline construction and operational expenditure savings and also the operational expenditure savings associated with lower chemical and electricity use in the beach well plants. Construction phase contribution to treatment facilities life cycle environmental impact for the decentralised supply system was found to be higher than for the centralised supply system due to diseconomy of scale in smaller-sized plants. However, this was outweighed by significant water distribution pipeline construction and operational environmental impacts savings. Smaller plants with beach well intake benefit from operational environmental impact savings associated with lower chemical and electricity use. Multi-staged construction of successive small plants compared to single-stage construction of a large plant provided better economic outcomes due to lower interest costs. However, multi-staged construction led to higher environmental impacts associated with diseconomy of scale in the plant construction phase. The case study provided numerous insights that were only possible through the use of a life-cycle optimization framework. For example, in desalination planning for a metropolitan area with land scarcity for siting new plants, the factors of supply system configuration, land-use patterns, environmental impacts and economic costs are highly inter-related and decision makers can consider these as a whole rather than considering each separately. The transparency and flexibility of the framework allows professionals from different disciplines to test the scenarios in a quantitative manner, to understand potential planning implications.

This work of thesis studies the approach of the Water Safety Plan, that is applied to a part of the drinking water supply network managed by AIMAG S.p.A. The Water Safety Plans have been introduced by the World Health Organization and have been identified as the most effective way to systematically guarantee the safety of the drinking water system, the quality of the water supplied, and the protection of the health of consumers. Through a preventive and qualitative analysis that includes risk assessment and management, the Water Safety Plans make it possible to guarantee over time the absence of potential physical, biological, and chemical hazards in the water available for consumption. The result obtained through the application of the Water Safety Plan involves the construction of a risk matrix, that allows the development of an improvement plan for the control of each hazard and associated risk (in priority scale). After that, the previously performed analysis is supported through the application of statistical and probabilistic techniques used in the reliability analysis to optimize the control activities based on a risk assessment. The first one is the Fault Tree Analysis, which is a deductive technique supported by Boolean algebra that focuses on a particular undesirable event and provides a method for identifying possible causes. In parallel with the application of the Fault Tree Analysis, the Monte Carlo method is applied, which is a computational method based on random sampling of certain variables to obtain numerical results. Finally, the result obtained through the application of both methodologies is the definition of the probability of failure of some nodes and internodes that are part of a portion of the drinking water supply network managed by AIMAG S.p.A. At the end, the work of thesis lead to results which prove that the qualitative approach of the Water Safety Plans can be effective, especially if supported by different types of analysis.

The Lesotho Highlands Development Authority routinely uses the South African Scoring System version 4 (SASS4) in conjunction with water chemistry to monitor water quality of rivers in the Lesotho Highlands Water Project areas. The objective of this study was to test the efficiency of SASS4 in these areas.

The main objective of the present research was to assess the environmental impacts of the provision of potable water supplies and sanitation projects, both during the construction and operation phases. The research was related to rural areas of developing countries. Field research was undertaken in the rural areas of the Northwest and Central regions of Iran. Data were obtained by observations and survey from the field, and a comprehensive questionnaire and literature review. Interviews were carried out by the author in households, particularly women, in four villages with a piped water supply and sanitation facilities, and four villages without such facilities, in the two different regions. To assess the beneficial and negative impacts stemming from the projects, Environmental Impact Assessment (EIA) techniques were used. After the application of EIA through the use of checklist of impacts and the Leopold's matrix, results demonstrated that the implementation of water supply and sanitation projects can have several negative impacts on the natural environment, and positive beneficial impacts on the social and economic environment. In relation to water supply and sanitation projects, the most effective EIA method was shown by this study to be the Leopold's matrix. It can identify both positive and negative impacts and the interaction between the project activities and environmental parameters. The most important recommendations that stem from this research are, that project planners and water engineers should employ EIA methods in planning water projects, particularly in the rural areas of developing countries.

Water supply companies operating within the European Union (EU) have a statutory duty to provide water that is wholesome to drink. To ensure continued compliance with EU water quality regulations together with reductions in operating costs it is necessary to optimise the use of raw water supplies. In order to do this successfully, a knowledge of the potential risks to water quality within a supply catchment is required. This thesis describes the development of a novel methodology to assess pollution risks in public water supply catchments. The Risk Assessment of Supply Catchments And Land (RASCAL) methodology consists of four interrelated stages to identify, estimate, evaluate and manage risks to water quality. The methodology is generic in nature thus allowing the transfer of the approaches developed to other catchment areas. The potential of geographical information systems (GIS) as a tool assessing pollution risks in supply catchments is identified from an extensive review of water quality hazards and the use of GIS in the UK water industry. This potential is explored further through the example application of the RASCAL methodology to the Upper Wharfe catchment area. The thesis describes an important development in assessing catchment risks, the construction of catchment-scale hazard maps using logical structures (Source Trees) and GIS data models. In this way, the probable extent of point and diffuse sources of pollution are identified for the entire catchment area of a surface water intake. The use of generically available digital data allows the production of hazard maps for ten water quality issues potentially affecting the Upper Wharfe source. These digital hazard maps are also used in the development of a raw water sampling programme. The results from this programme confirm the ability of the digital maps to identify the source of water quality hazards using generic data. Quantitative approaches relying on the acquisition of large amounts of historical or background data are found to be inherently inappropriate for a generic methodology. The availability of water quality data is identified as a fundamental barrier to the successful preparation of such quantitative frequency estimates. This research combines quantitative and qualitative approaches to provide a valid methodology of risk assessment for generic application. A fundamental characteristic of the methodology developed is this mixture of quantitative, semi- quantitative and qualitative techniques encompassed within it. This represents a significant contrast to the traditional hard-engineering approaches to risk assessment applied in past studies where the emphasis has been on the quantitative estimation of risk. The use of digital data and GIS allow the most suitable technique to be identified and displayed.

This research examines the collective action and financial dimensions of rural waterpoint sustainability in sub-Saharan Africa. Four interlinking papers empirically evaluate the nature and drivers of financial risks, and how they in turn impact the operational performance of community water supplies. The research is grounded in conceptual and theoretical frameworks pertaining to collective action and common-pool resource management, in particular Ostrom's social-ecological systems framework (Ostrom, 2007), Musgrave & Musgrave's economic good framework (Musgrave & Musgrave, 1973), and Marwell & Oliver's critical mass theory (Marwell & Oliver, 1993). The first paper analyses data extracted from national waterpoint inventories in Liberia, Sierra Leone, and Uganda. The remaining three papers draw on primary data from rural Kenya comprising 229 years' worth of water committee financial records, a census of 571 waterpoints, and a survey of 3,361 households. These data were collected during extensive field work campaigns in Kwale, Kenya. Quantitative analyses were carried out by way of advanced statistical techniques, including logistic regression, linear mixed (repeated measure) models, and generalised estimating equations. Results suggest collection of user fees is a significant determinant of waterpoint sustainability, alongside other institutional, technical, geographical and environmental variables. However, monthly payment arrangements are beset by non-payment and late payment, particularly if rainfall levels are high, group size is large, households are far away, and water is aggressive and unpalatable. Although monthly contribution levels remain relatively stable above a collective payment rate of 60%, there is little evidence of self-sustaining growth beyond this point, and revenue collection is prone to collapse below this collective payment threshold. In comparison, pay-as-you-fetch fees are associated with increased revenue and improved operational performance, but result in a higher proportion of households opting for an unimproved water source. If the Sustainable Development Goal of universal access to safe water supplies is to be achieved in rural sub-Saharan Africa, strategies are needed to strengthen revenue collection systems and bolster payment incentives. External support and professionalised service delivery models present potential pathways to advance these goals. Policymakers may also need to introduce carefully designed subsidies, or promote self-supply approaches that realign lifecycle costs with users' willingness-to-pay.

Faecal contamination in water is detected using appropriate microbial models such as total coliforms, faecal coliforms and E. coli. Βeta-D-Galactosidase (β-GAL) and Beta-D-glucuronidase (β-GUD) are two marker enzymes that are used to test for the presence of total coliforms and E. coli in water samples, respectively. Various assay methods have been developed using chromogenic and fluorogenic substrates. In this study, the chromogenic substrates chlorophenol red β-D-galactopyranoside (CPRG) for β-GAL and p-nitrophenyl-β-D-galactopyranoside (PNPG) for β-GUD were used. Potential problems associated with this approach include interference from other organisms present in the environment (e.g. plants, algae and other bacteria), as well as the presence of certain chemicals, such as phenolic compounds in water. Phenolic compounds are present in the aquatic environment due to their extensive industrial applications. The USA Enviromental Protection Agency (EPA) lists 11 Priority Pollutant Phenols (PPP) due to their high level of toxicity. This study investigated the interfering effects of the eleven PPP found in water on the enzyme activities of both the β-GAL and β-GUD enzyme assays. The presence of these PPP in the β-GAL and β-GUD enzyme assays showed that over and underestimation of activity may occur due to inhibition or activation of these enzymes. Three types of inhibition to enzyme activities were identified from double reciprocal Lineweaver-Burk plots. The inhibition constants (Ki) were determined for all inhibitory phenolic compounds from appropriate secondary plots. Furthermore, this study presented a validated reverse phase high performance liquid chromatography (RP-HPLC) method, developed for the simultaneous detection, separation and determination of all eleven phenolic compounds found in the environment. This method demonstrated good linearity, reproducibility, accuracy and sensitivity. Environmental water samples were collected from rivers, streams, industrial sites and wastewater treatment plant effluent. These samples were extracted and concentrated using a solid phase extraction (SPE) procedure prior to analysis employing the newly developed HPLC method in this study. Seasonal variations on the presence of the PPP in the environment were observed at certain collection sites. The concentrations found were between 0.033 μg/ml for 2,4-dinitrophenol in a running stream to 0.890 mg/ml for pentachlorophenol from an tannery industrial site. These concentrations of phenolic compounds found in these environments were able to interfere with the β-GAL and β-GUD enzyme assays.

This dissertation explores the impact of climate change and extreme weather events on critical infrastructures as defined by US Department of Homeland Security. The focus is on two important critical infrastructure systems – Water and Transportation. Critical infrastructures are always under the risk of threats such as terrorist attacks, natural disasters, faulty management practices, regulatory policies, and defective technologies and system designs. Measuring the performance and risks of critical infrastructures is complex due to its network, geographic and dynamic characteristics and multiplicity of stakeholders associated with them. Critical infrastructure systems in crowded urban and suburban areas like the Washington Metropolitan Area (WMA) are subject to increased risk from geographic proximity. Moreover, climate is challenging the assumption of stationary (the idea that natural systems fluctuate within an unchanging envelope of variability) that is the foundation of water resource engineering and planning. Within this context, this research uses concepts of systems engineering such as 'systems thinking' and 'system dynamics' to understand, analyze, model, simulate, and critically assess a critical infrastructure system's vulnerability to extreme natural events and climate change. In most cases, transportation infrastructure is designed to withstand either the most extreme or close to the most extreme event that will add abnormal stresses on a physical structure. The system may fail to perform as intended if the physical structure faces an event larger than what it is designed for. The results of the transportation study demonstrate that all categories of roadways are vulnerable to climate change and that the magnitude of bridge vulnerability to future climate change is variable depending on which climate model projection is used. Results also show that urbanization and land use patterns affects the susceptibility of the bridge to failures. Similarly, results of the water study indicate that the WMA water supply system may suffer from water shortages accruing due to future droughts but climate change is expected to improve water supply reliability due to an upward trend in precipitation and streamflow.
Ph. D.

The precipitation data of the El Alto, Tambillo and Comanche stations are homogenous and consistent. The meteorological data from Irpa Chico, Collana and Viacha are consistent, but heterogeneous. The monthly precipitation in Viacha in December, January, March and April are better examples of a normal distribution in comparison to the months of October, November and February. The average annual precipitation in Viacha, in a thirty-four year time period, is 559 mm. Some 76% of this precipitation occurs in November to March. The minimum precipitation in Viacha, with an 80% probability of absence for the vegetative period, from October to April is 269mm. January is the month with the most precipitation (75 mm). The estimated potential of evaporation-transpiration with the Penmen-Monteith method is 1,168 mm a year. October constitutes the month with the greatest value of ETP (116mm). The maximum volume of food storage in the Calacalani Lagoon is 137,000 m3, with annual losses of 48,218 m3. 82% of these losses are due to evaporation and 18% due to infiltration. The usable water volume, taking into account the conservation of 30% of the total volume in order to maintain the aquatic fauna and flora, is 47,740 m3. With some exceptions, the quality of the water is suitable for livestock consumption and with an estimated irrigation capacity of 7-11 hectares per year. The Jacha Jahuira River- Pallina transports an average volume of 38.5x106 m3 annually. This presents serious restrictions for water use in agricultural irrigation and human consumption. The use of the River's water for agricultural purposes has been conditioned for special handling operations, which can reach an irrigational surface of 5,199-8,665 hectares/year. The ground water level may vary from 3,867-3,843 m over that of the ocean level. This presents a fluctuation of 1.2 m in the deep valley receptors of the Letanias hill country and 0.1 m in the community presented an average flow of 0.13 l/s, which represents a volume of 4,100 m3/year. The artesian or subterranean water represents an interesting potential for its quality as well as its availability of 788,000 m3/year of volume. With 12 hours of daily pumping of this water, some 53-88 hectares/year are suitable for irrigation. This is in spite of the fact that the lack of infrastructure has provoked the abandonment of deeply excavated wells, estimating an annual lose of 145,00 m3. Artesian water has no restriction in quality, for animal and human consumption or for irrigation purposes. Some ground water wells have been restricted for human use, due to bacterial contamination. The Choquenaira Community is located in the middle valley of the Jacha Jahuira-Pallina. In the high valley the reduction of vegetation coverage is being observed, that when combined with seasonal rains, provokes water erosion and the transportation of sediment through drainage; Estimating an average transportation of 104 TM of sediments in suspension, especially during the rainy seasons (December-March). In the lower valley severe biological contamination (for human consumption) has been detected. This is due to the discharge of service water from the Viacha City sewer system and the Laja population; and so the sediment accumulation, increasing the risk of overflow and flooding. Extreme events, such as flooding that exceed 50 million m3 of annual drainage, have happened four times in 52 years; which is approximately every 13 years. There is an annual 76% probability that a major event will not occur. The micro-region of the Choquenaria covers a total area of 2,126 hectares. Some 12% (262 hectares) are covered with pastures in a humid environment and temporarily or permanently flooded areas (bofedales, and fertile plains); 19% (401 hectares) are covered steeps, shrubs, and rocky outcrops with strong inclines; 69% (1,463 hectares) correspond to dry land cultivations, pastures, and or bushes that lack distinction. The highest quality springs are used for human consumption, which is estimated to be 10 liters/inhabitant/day, representing an overall community consumption of 594 m3/year (148 inhabitants). This level of consumption is low in comparison to that of the Bolivian, 30-50 l/habitant/day, which is due to the difficulty in accessing the water source. With an average cattle possession in a family being five bovines and 40 ovine, the average consumption is from 450 l/possession/day. This represents an annual consumption of 10,374 m3 used for livestock water in the Choquenaira Community. The surface that undergoes irrigation in the winter does not exceed 600 m2, which is a surface that needs 440 m3/year. The requirement or unitary demand for a cultivation system, consisting of barley (57%), potato (28.6%), and alfalfa (14.4%) in the Choquenaira Community is about 4,443 m3/hectares/year, assuming an irrigation efficiency of 100% and 7,405 m3/hectares/year with a 60% efficiency using a surface irrigation system. The inhabitants of the community use an operational strategy of national resources (ground, water, cultivations, etc.) on the basis of availability and incidence of climatic resources, with the use of local ecological indicators to predict the climate. The commoners seek the reduction of agricultural risk, through specialization in hydric cultivation (dry farming) crops, the spatial operations (epochs), water conservation (water gathering) and the diversification of fountains/springs. There are oftentimes-distinct gender roles in the community. Agriculture is considered a productive activity, in which men play the dominant role. Whereas the women play a fundamental role in obtaining water, especially that which is used in human and animal consumption. The overall offering of the local hydraulic system, composed of the contribution of the Jacha Jahuira River, Calacalani Lagoon, the ground water, and artesian wells, is 39.3 million meters cubed per year. The actual demand of the community, that includes human and animal consumption as well as the irrigation in winter pastures, reaches 11,381m3/year. The potential demand, that includes both human and animal consumption, irrigation in winter pastures and the supplementary irrigation of dry farming, reaches 3.2 million meters cubed per year. The local hydraulic system offers volumes of water, sufficient enough to meet the community's actual and potential demand. However, its contamination and difficulty to access has caused the inhabitants to develop spatial and temporary strategies in order to access the water. The commoners consider the developments of these hydric resources, especially that of human consumption, as a short and long term necessity.

This study was carried out to characterize ponds and aquaculture systems, and also to determine both the potential and actual impacts of pond aquaculture effluents on receiving stream quality in the Ashanti and Brong Ahafo regions of Ghana. Water, fish and macroinvertebrate samples were collected from upstream, downstream and nearby reference streams of, and questionnaires administered to, 32 farms. Total settleable solids were higher in ponds than reference streams (p = 0.0166); suspended solids was higher in ponds than reference streams (p = 0.0159) and upstream (p = 0.0361); and total phosphorus was higher in ponds than reference (p = 0.0274) and upstream (p = 0.0269). Total nitrogen was most clearly higher in ponds than all other locations: p = 0.0016, 0.0086 and 0.0154 for the differences between ponds and reference, upstream, and downstream respectively. BOD5 level was also higher in ponds than all locations (p = 0.0048, 0.0009, and 0.0012 respectively). Also, non-guarding fish species were more abundant in reference streams than downstream (p = 0.0214) and upstream (p = 0.0251), and sand-detritus spawning fish were less predominant in reference streams than upstream (p = 0.0222) and marginally less in downstream locations (p = 0.0539). A possible subsidy-stress response within study streams was also observed. Hence, ponds are potential sources of these water quality variables to receiving streams. Effluent-receiving streams, generally, were not much different from reference streams in terms of most the metrics of community structure and function used in the comparisons. Hence, even though receiving streams in Central Ghana may not be severely impacted by aquaculture effluents at the moment, the management of pond effluents will determine the scale of future impact. Vegetable, cereal, and livestock farming could serve as additional sources of fecal streptococci and coliform bacteria and nutrient-enrichment within the study area, besides aquaculture, and so these industries must also be included in efforts to minimize pollution of these streams.
Master of Science