Water resources in tourist islands have been severely threatened, especially in the Galapagos Islands, where the increased local population has generated attractive income from the tourist services. In addition, the data regarding water supply and demand are scarce. This study investigates water supply and demand in Santa Cruz, the most populated island of Galapagos. The research encompasses a thorough assessment of the water supply crisis, as well as the quantification of water demand from different categories (domestic, tourist, restaurants and laundries) through surveys, in the absence of water metering. Also, specific water demand was assessed by installing 18 water meters. The results yield a wide range of water consumption, questioning the current assumption of water scarcity. Furthermore, a prognosis of water supply and demand was carried out, and also several intervention strategies were proposed such as rainwater harvesting, greywater recycling, leakage reduction, water meter installation, water demand reduction, as well as seawater desalination to cope with the future population growth. Due to the fragility of the ecosystem, these strategies were assessed through a Multi-Criteria Decision Analysis, considering environmental, technical, economic and social aspects, as well as relevant stakeholders' perspectives. finally, the water supply network of Puerto Ayora was evaluated in order to understand the need of the current intermittent supply regime. A methodology was developed to estimate the overflow of the domestic roof tanks (a common incidence amongst local population). The results question the practicality of individual household storage. The final results show that the current situation in terms of the lack of water quantity may not be real, as it has been thought for the last decades. The water issues refer more importantly to the water quality, as well as to the lack of proper water management practices.

Urban flood risks and their impacts are expected to increase as urban development in flood prone areas continues and rain intensity increases as a result of climate change while aging drainage infrastructures limit the drainage capacity in existing urban areas. Flood mitigation strategies are required as part of sound urban flood management plans to assess flood risk and identify technically feasible and cost-effective options to reduce the risk. Central to the development of flood mitigation strategies is the efficient prediction of flood propagation characteristics in urban areas. Detailed predictions of flood flows in urban areas require the use of high resolution topographic data. However, due to computational demand topographic data is often generalised to a more manageable resolution and floodplain models are built at much coarser resolutions. The research presented in this thesis addresses the problem of capturing small-scale features in coarse resolution urban flood models with the aim of improving flood forecasts in geometrically complex urban environments. The approach adopted in the research used a two-dimensional surface flow modelling system that can extract and incorporate useful information available in high resolution topographic data into coarse grid models. The thesis also presents modelling of the complex interaction between surcharged sewer and flows associated with urban flooding and incorporation of infiltration process in surface flow modelling tools. Case study results showed that the incorporating volume-depth and flow-area-depth relationships extracted from high resolution topographic data significantly improved the results of coarse grid urban flood models while taking the advantage of reduced computational time to ensure efficient prediction of urban flood characteristics.

Urban informal settlements or slums are growing rapidly in cities in sub-Saharan Africa. Most often, a sewer system is not present and the commonly-used low-cost onsite wastewater handling practices, typically pit latrines, are frequently unplanned, uncontrolled and inefficient. Consequently, most households dispose of their untreated or partially treated wastewater on-site, generating high loads of nutrients to groundwater and streams draining these areas. However, the fate of nutrients in urban slums is generally unknown. In excess, these nutrients can cause eutrophication in downstream water bodies. This book provides an understanding of the hydro-geochemical processes affecting the generation, fate and transport of nutrients (nitrogen and phosphorus) in a typical urban slum area in Kampala, Uganda. The approach used combined experimental and modeling techniques, using a large set of hydrochemical and geochemical data collected from shallow groundwater, drainage channels and precipitation. The results show that both nitrogen-containing acid precipitation and domestic wastewater from slum areas are important sources of nutrients in urban slum catchments. For nutrients leaching to groundwater, pit latrines retained over 80% of the nutrient mass input while the underlying alluvial sandy aquifer was also an effective sink of nutrients where nitrogen was removed by denitrification and anaerobic oxidation and phosphorus by adsorption to calcite. In surface water, nutrient attenuation processes are limited. This study argues that groundwater may not be important as regards to eutrophication implying that management interventions in slum areas should primarily focus on nutrients released into drainage channels. This research is of broad interest as urbanization is an ongoing trend and many developing countries lack proper sanitation systems.

The rate of global increase in water abstraction for irrigation has been declining since the 1970's due to declining potentials for large and medium-scale irrigation developments, and is expected to further decline in the next decades. As such the significant proportion of the expected increase in production would have to be supplied from existing irrigated and /or cultivated lands. This in turn could be achieved by enhancing land and water productivity through improved performance and optimal operation and maintenance. With less than 15% of over 5 million ha irrigation potential harnessed, irrigation devolvement in Ethiopia remained low. Over 70% of the developed irrigation in the country belongs to small-scale irrigation serving smallholder farmers. While accelerated development of new irrigation, particularly of large and medium-scale schemes is relevant in Ethiopia, ensuring the performance and sustainability of existing schemes is also equally important. The existing irrigation schemes in Ethiopia are generally characterized by an overall performance and technical sustainability levels of below expectation. This thesis evaluates the performance of two large-scale (Wonji-Shoa and Metahara) and two community-managed (Golgota and Wedecha) irrigation schemes located in the Awash River Basin of Ethiopia. The study focussed on hydraulic/water delivery performance in the large-scale schemes, and on comparative and internal irrigation service (utility) evaluation in the community-managed schemes. Water delivery performance was evaluated using routine data and hydrodynamic modelling. Farmers' utility was evaluated using qualitative responses of water users. Major performance challenges in each category of schemes were addressed and operational/water management options for improvement were identified.

Africa has been severely affected by droughts in the past, contributing to food insecure conditions in several African countries. In view of the (even more) severe drought conditions and water shortage that may be expected in sub-Saharan Africa in the coming years, efforts should focus on improving drought management by ameliorating resilience and preparedness to drought. This study contributes to the development of a modelling framework for hydrological drought forecasting in sub-Saharan Africa as a step towards an effective early warning system. The proposed hydrological drought forecasting system makes use of a hydrological model that was found to be suitable for drought forecasting in Africa and could represent the most severe past droughts in the Limpopo Basin. The modelling results showed that there is an added value in computing indicators based on the hydrological model for the identification of droughts and their severity. The proposed seasonal forecasting system for the Limpopo Basin was found to be skilful in predicting hydrological droughts during the summer rainy season. The findings showed that the persistence of the initial hydrological conditions contribute to the predictability up to 2 to 4 months, while for longer lead times the predictability of the system is dominated by the meteorological forcing. An effective drought forecasting and warning system will hopefully contribute to important aspects in the region such as water security, food security, hazard management, and risk reduction.

This work investigated two different approaches to optimize biological sulphate reduction in order to develop a process control strategy to optimize the input of an electron donor and to study how to increase the feasibility of using a cheap carbon source. Feast/famine regimes, applied to design the control strategy, were shown to induce the accumulation of storage compounds in the sulphate reducing biomass. This study showed that delays in the response time and a high control gain can be considered as the most critical factors affecting a sulphide control strategy in bioreactors. The delays are caused by the induction of different metabolic pathways in the anaerobic sludge, including the accumulation of storage products. On this basis, a mathematical model was developed and validated. This can be used to develop optimal control strategies. In order to understand the microbial pathways in the anaerobic oxidation of methane coupled to sulphate reduction (AOM-SR), diverse potential electron donors and acceptors were added to in vitro incubations of an AOM-SR enrichment at high pressure. Acetate was formed in the control group, probably resulting from the reduction of CO2. These results support the hypothesis that acetate may serve as an intermediate in the AOM-SR process.

The aim of this book is to contribute to understanding risk knowledge and to forecasting components of early flood warning, particularly in the environment of tropical high mountains in developing cities. This research covers a challenge, taking into account the persistent lack of data, limited resources and often complex climatic, hydrologic and hydraulic conditions. In this research, a regional method is proposed for assessing flash flood susceptibility and for identifying debris flow predisposition at the watershed scale. An indication of hazard is obtained from the flash flood susceptibility analysis and continually, the vulnerability and an indication of flood risk at watershed scale was obtained. Based on risk analyses, the research follows the modelling steps for flood forecasting development. Input precipitation is addressed in the environment of complex topography commonly found in mountainous tropical areas. A distributed model, a semi-distributed model and a lumped model were all used to simulate the discharges of a tropical high mountain basin with a paramo upper basin. Performance analysis and diagnostics were carried out in order to identify the most appropriate model for the study area for flood early warning. Finally, the Weather Research and Forecasting (WRF) model was used to explore the added value of numerical weather models for flood early warning in a paramo area.

Mountains are water towers of our world, but their role in global water resources may be altered due to changing climate. This book provides an integrated assessment of the spatial and temporal variability of both recent and future climate change impacts in the Yellow River source region (YRSR) with specific focus on extremes. The book is structured across four different topics from detecting contemporary hydro-climatic changes, comparing three different statistical downscaling methods, assessing elevation dependency of expected changes in temperature, and projecting future climate-induced hydrologic changes in the YRSR. The detection of historical hydro-climatic changes in recent decades indicates that climate change may already be happening and may pose a serious threat to water availability in this region. However, an ensemble of climate change projections for the periods 2046-2065 and 2081-2100 based on two GCMs and three emission scenarios demonstrates that the future water availability of this region would increase due to climate change. This discrepancy suggests that contemporary hydro-climatic experience based on past records alone may not always provide a reliable guide to the future. This study makes an important contribution toward an improved understanding of climate change impacts in the YRSR. The knowledge generated has major implications for water resources management in the Yellow River and will be instructive for climate change impacts studies in other mountain areas.

Providing an introduction to the crucially important topic of groundwater, this text covers all major fields of hydrogeology and includes outlines of the occurrence of groundwater in various rock types, the movement and storage of groundwater, the formulation of groundwater balances, the development of groundwater chemistry, as well as the practical application of hydrogeology for groundwater development. Following a unique systems approach to describe and connect its various elements, the text also explores a large selection of examples of groundwater cases from various parts of the world. In addition, theoretical sections and examples are illustrated with a number of drawings, photos and computer printouts. Suitable for education in hydrogeology at postgraduate and graduate level, the text is also a useful reference tool for professionals and decision-makers involved in water or water-related activities. In the revised paperback edition more attention is paid to the processes in the unsaturated zone, especially those relating to groundwater recharge. Also, the investigation methods are highlighted in the sections where the related theory is dealt with, and they are not presented in the last chapter on groundwater management. The References and Bibliography section is also extended, some figures are improved, and the inevitable 'typing errors' are corrected as well. In the third edition, a more formal basis for the hydro-chemical processes described in the chapter on groundwater chemistry has been added. Mass balances and the principles of dispersion and retardation are introduced. Additional illustrations are provided, also explaining the processes occurring along streamlines. Consult: http://introductiontohydrogeology.nl/ for additional information on the book, the author and available software.

Since the 1980s a major change took place in public policies for water resources management. The role of governments shifted under this reform process from an emphasis on investment in the development, operation and maintenance of water infrastructure to a focus on managing water resources systems by stipulating general frameworks and defining key principles for water allocation. This interdisciplinary research examines how this water reform process unfolds within four African waterscapes that are historically constituted by natural and social processes. The study analyzes the interplay between public policies designed and implemented by government agencies and the institutions that govern access to and control over water resources among groups of agricultural water users. The findings of this research show that the water reform policies have led to similar outcomes in dissimilar contexts and that water policy only to a limited extent leads to progressive institutional change concerning agricultural water use, especially in this neoliberal era. Moreover, this research shows that excluding targeted investments in the development of hydraulic infrastructure for historically disadvantaged groups has narrowed the options of the governments to redress the colonial legacy and the capacity of small-scale farmers to move their livelihood beyond subsistence.

A considerable amount of scientific evidence has been collected leading to the conclusion that urban wastewater components should be designed as one integrated system, in order to protect the receiving waters cost-effectively. Moreover, there is a need to optimize the design and operation of the sewerage network and wastewater treatment plant (WwTP) considering the dynamic interactions between them and the receiving waters. This book introduces a method called Model Based Design and Control (MoDeCo) for the optimum design and control of urban wastewater components. The book presents a detailed description of the integration of modelling tools for the sewer, the wastewater treatment plants and the rivers. The complex modelling structure used for the integrated model challenge previous applications of integrated modelling approaches presented in scientific literature. The combination of modelling tools and multi-objective evolutionary algorithms demonstrated in this book represent an excellent tool for designers and managers of urban wastewater infrastructure. This book also presents two alternatives to solve the computing demand of the optimization of integrated systems in practical applications: the use of surrogate modelling tools and the use of cloud computer infrastructure for parallel computing.

The book presents documentary evidence of the insufficiency of rehabilitation works to close the gap between the irrigation service and actual area irrigated of publicly funded national irrigation systems in the Philippines. It outlines a methodology for formulating a modernisation plan for national irrigation systems with focus on the mostly ungauged, medium to small canal irrigation systems. The proposed methodology adaptively modified some known modernisation concepts and techniques and integrated them in a more holistic framework in the context of changing weather patterns and river flow regimes. It includes in-depth review of rehabilitation works; system diagnosis; revalidation of design assumptions on percolation and water supply; characterisation of system management, irrigation service and demand; and drawing up of options and a vision for the modernised irrigation systems. Central to the proposed modernisation strategy is the logical coherence among the design of physical structures, system operation and water supply so that improvements of irrigation service are possible. The book discusses the development of the proposed methodology and demonstrates its utility in two case study irrigation systems.

This monograph provides a framework and guidelines for the assessment of institutional frameworks for integrated water resources management (IWRM). The framework and guidelines were developed to enable expert teams of the Inter-American Development Bank to incorporate capacity-building considerations into water-related projects. The framework and guidelines were tested in four countries with different physical, social and economic environments in Latin America and the Caribbean. Using this framework, it is possible to identify shortcomings in existing water management arrangements and to formulate interventions at and between the constitutional, organizational, and operational levels. To guide the formulation of interventions, an ideal IWRM situation is formulated. Due to the temporal and spatial specificity, a desired IWRM situation is formulated in a process which consists of ten operational steps. This process is based on an extensive consultation and participation of all relevant stakeholders. The fields of interventions concern awareness creation, policy development, legal and financial arrangements, human resources development and management information and decision support systems.

After World War II, international development became the world leading development model, but its effectiveness is much debated. Nowadays, it is acknowledged that international development can effectively support development through knowledge and capacity development (KCD). Nonetheless, understanding what capacity really consists of in operational terms and what its development entails remains a challenge. This book investigates KCD processes in water utilities in Sub-Saharan Africa. The three cases analysed reveal that the learning impact of KCD on utilities depends on whether they are able to close their learning cycle, i.e., to ensure that improved capacity is also translated into mainstream behaviour. This finding challenges conventional wisdom for which KCD translates "automatically" into improved performance. Hence the need to focus KCD evaluation on both capacity improvement and capacity application. The proposed learning-based framework for KCD identifies two distinct but interrelated stages in KCD, namely knowledge transfer and knowledge absorption. Knowledge absorption usually takes time due to slow organisational processes that govern it. However, in practice it is often taken for granted. The framework also identifies the key factors that shape learning processes in water utilities. The book argues that water utilities in Sub-Saharan Africa can reinvent themselves by embracing change management approaches and striving to become learning organisations.

For integrated water resources management both blue and green water resources in a river basin and their spatial and temporal distribution have to be considered. This is because green and blue water uses are interdependent. In sub-Saharan Africa, the upper landscapes are often dominated by rainfed and supplementary irrigated agriculture that rely on green water resources. Downstream, most blue water uses are confined to the river channels, mainly for hydropower and the environment. Over time and due to population growth and increased demands for food and energy, water use of both green and blue water has increased. This book provides a quantitative assessment of green-blue water use and their interactions. The book makes a novel contribution by developing a hydrological model that can quantify not only green but also blue water use by many smallholder farmers scattered throughout the landscape. The book provides an innovative framework for mapping ecological productivity where gross returns from water consumed in agricultural and natural vegetation are quantified. The book provides a multi-objective optimization analysis involving green and blue water users, including the environment. The book also assesses the uncertainty levels of using remote sensing data in water resource management at river basin scale.

International cooperation for reaching development goals has expanded gradually since the 1950s. The effectiveness of the Overseas Development Aid (ODA) has become a topic of great public interest. A growing body of experience exists to demonstrate that finance alone is not sufficient for development, and capacity and knowledge are increasingly seen as the constraints to proper decision making, absorption of funds, and effective results on the ground. This book presents the investigation into the role of Knowledge and Capacity Development (KCD) in public water resources management in Indonesia and the Netherlands. The two cases indicate that the institutional environment is defining for the type of knowledge and capacity development that is prevailing in that period and it also determines the formal organisational structure and the KCD mechanisms in use. The cases further show the importance yet the low valuation of tacit knowledge, while the Indonesian case also suggests that tacit knowledge is among the most important assets gained from international post-graduate education. The conceptual model introduced in this book allows to measure knowledge and capacity at three nested levels: the institutional, organisational and individual level. It provides insight in the numerous contextual factors that influence knowledge and capacity and KCD mechanisms.

The unprecedented growth of cities has a significant impact on future flood risk that might exceed the impacts of climate change in many metropolitan areas across the world. Although the effects of urbanisation on flood risk are well understood, assessments that include spatially explicit future growth projections are limited. This comparative study provides insight in the long term development of future riverine and pluvial flood risk for 18 fast growing megacities. The outcomes provide not only a baseline absent in current practise, but also a strategic outlook that might better establish the role of urban planning in limiting future flood risk.

The role of small hydropower is becoming increasingly important on a global level. Increasing energy demand and environmental awareness has further triggered research and development into sustainable low-cost technologies. In developing countries, particularly in rural areas, the possibility of local power generation could considerably improve living conditions. With this in mind, the development of a next generation low-head hydropower machines was subject of investigation in the EU-project HYLOW. Being part of the research lines of that project, this thesis presents a numerical modelling approach to improve the design of machines like water wheels for increased hydraulic efficiency. Nowadays, Computational Fluid Dynamics (CFD) enables numerical models to be quite accurate and incorporate physical complexities like free surfaces and rotating machines. The results of the CFD simulations carried out in this research show that a change in blade geometry can result in higher torque levels, thereby increasing performance. Numerical simulations also enabled to determine the optimal wheel-width to channel-width ratio and further improve performance by modifying the channel bed conditions upstream and downstream of the water wheel. With a power rating in the low kilowatt range, low-head hydropower machines like optimised water wheels seem to have a clear potential for small-scale energy generation, thereby contributing to achieving the Sustainable Development Goals by providing local energy solutions.

Professionals in the water supply industry are faced with a mass of technical information about how best to use new technologies to improve the efficiency of their supply operations. This text is designed to help explain practical problems and potential solutions clearly and comprehensively to readers who may not be familiar with the latest development in IT and computing. Managers should find it useful in understanding the data requirements of these new systems and it will help them make the most of available resources. It should be of use to those planning and designing new systems and those working with existing ones.

Sediment pollution and accumulation in harbours are major environmental issues and studies that advance their solutions are essential for harbour sustainability. This book provides the first comprehensive assessment of chemical pollution in sediments and sediment accumulation rates in the tropical Tema Harbour (Ghana). This book contributes to improving our ability to use an integrated approach involving sediment chemistry and bioassays in one comprehensive assessment of the contamination state of a tropical coastal environment. Whole-sediment toxicity bioassays using the amphipod Corophium volutator and the polychaete Hediste diversicolor as bioindicators were combined with data on concentrations of total metal and metal binding forms, radionuclides, organochlorine pesticides and polycyclic aromatic hydrocarbons in bottom sediments as well as total metal concentrations in settling silt-clay particles collected by sediment traps to characterise the hazard, risk and impact of sediments from the tropical coastal Tema Harbour.

This research investigated new approaches to control anaerobic methane oxidation coupled to sulfate reduction (AOM-SR) and enrich anaerobic methanotrophs (ANME) and sulfate reducing bacteria (SRB) with the purpose of designing a suitable bioreactor for AOM-SR at ambient pressure and temperature. The current knowledge about AOM and the microorganisms involved in AOM are discussed. The effect of different substrates and pressures was investigated on the ANME and SRB community adapted to the shallow marine Lake Grevelingen, the Netherlands. Further, microorganisms from the Alpha Mound (Spain) deep sediment were enriched with methane gas as substrate in biotrickling filters (BTF) at ambient conditions for 147-230 days of operation. The effect of alternative sulfur compounds (sulfate, thiosulfate and elemental sulfur) were studied and the microbial community was characterized. The highest AOM and sulfate reduction rates were obtained in the BTF fed with thiosulfate as the electron acceptor (~0.4 mmol l-1 day-1), but the highest number of ANME was visualized in the sulfate fed BTF (ANME-2 43% of the total visualized archaea). A BTF was proposed as a suitable bioreactor for the enrichment of ANME and SRB at ambient pressure and temperature which could be potentially used for future biotechnological applications.

Anaerobic oxidation of methane (AOM) coupled to sulfate reduction (AOM-SR) is a biological process mediated by anaerobic methanotrophs (ANME) and sulfate reducing bacteria. It has scientifi c and societal relevance in regulating the global carbon cycle and biotechnological application for treating sulfate-rich wastewater. This research aimed to enhance the recent knowledge on ANME distribution and its enrichment in different bioreactor confi gurations, i.e. membrane bioreactor (MBR), biotrickling fi lter (BTF) and high pressure bioreactor (HPB). Marine sediment from Ginsburg mud volcano, Gulf of Cadiz was used as inoculum in the BTF and MBR. The BTF operation showed the enrichment of ANME in the biofi lm, especially ANME-1 (40%) and ANME-2 (10%). Whereas, the dominancy of ANME-2 and Desulfosarcina aggregates was observed in the MBR. Moreover, HPB study was performed by using highly enriched ANME-2 community from Captain Arutyunov mud volcano. During the study of HPB at different temperature and pressure conditions, the incubation at 10 MPa pressure and 15 C was observed to be the most suitable condition for the studied AOM-SR community. Furthermore, AOM-SR activity in the coastal sediments from marine Lake Grevelingen (the Netherlands) was explored and the microbial community was characterised which was dominated by ANME-3 among known ANME types.

This volume in the Fundamentals for the Water and Wastewater Main Operator series covers the basics of piping and valves in water and wastewater plants, including details on fittings, strainers, filters, traps and control systems. The book explains how pipes and valves are used to feed materials (e.g., chemicals) into influents and effluents and siphon off unwanted liquid and gaseous by-product. Also covered is how pipes are developed into systems and subsystems and coordinated into a plant-wide functioning unit.

This volume provides readers with an opportunity to learn from front line water managers of watershed-based agencies across Canada about integrated water management (or integrated water resource management). In common with practice in much of the world, the responsibility for implementing integrated watershed management in Canada is fragmented. Each province and territory in Canada has developed unique approaches or governance models to guide decision making in that regard. Thus, this edited volume enables readers from around the world to gain insight on the best practices in Canada for achieving success and addressing barriers to implement IWM. Although there remains non consensus about how to "best" approach river basin management, some of the main observations include: There is a need to balance a focus on "the big picture", with scoping the scale and scope of planning activities in order that feasible and effective solutions can be implemented Three types of integration are popular among the agencies included in the book: (i) among environment, economy and society, (ii) interactions between people and the environment and (iii) integration (or coordination) of administrative activities. Much more attention is required to achieving effective engagement from Indigenous communities The chapters were originally published in a special issue of the International Journal of Water Resources Development.

A comprehensive and detailed study on the scaling potential of calcium carbonate in seawater reverse osmosis systems (SWRO), this book provides a new approach for calculating the degree of supersaturation and the pH of the SWRO systems concentrates with the assistance of the feed-water pH and the inorganic carbon constituents. Furthermore, the book highlights the weakness in the present supersaturation indices and membrane manufacturers programs. Finally, the research suggested that SWRO concentrate is much lower undersaturated with respect to calcium carbonate than previously thought. This was confirmed by comprehensive pilot testing where acids and antiscalants used to prevent calcium carbonate scaling were completely eliminated from the pilot plant.