First published in 1978: The purpose of this two-volume series is to present a consolidated and comprehensive reference on oxygen-activated sludge technology.

This book covers the advantages, limitations and operational standards for common land application of biosolids practices, including uses on agricultural lands, forest lands, reclamation sites, and public and private use sites. It is useful to people in all aspects of the wastewater industry.

Regulation of India's rivers and other water systems has been evolving for thousands of years in the face of varying socioeconomic and technological conditions. India's Waters: Environment, Economy, and Development is a study of the current state of development, and proposed future development policies of the government of India, which is the developmental agency. The author first addresses India's physical and hydrological environment. He explains how the government, using his research, has estimated its usable resources and water requirements for life, environment, and economy for the next half-century. The book describes how, based on its own assessment, the government has made detailed suggestions about developing India's water resources. After covering the overall national study and analysis, the author addresses the current development of the major river basins- the Indus and Ganges-Brahmaputra-Meghna (GBM) basins, as well as the Central, Peninsular and others. He follows with analysis of watershed, groundwater, and command area development. Inter-basin water transfer has been considered throughout India's long history. This book briefly details suggestions for interlinking India's rivers and concludes by presenting legal framework and institutional issues. This is the first of Dr. M.C. Chaturvedi's three studies on the waters of India. The second, India's Waters: Advances in Development and Management, presents his proposals for revolutionizing their development, and the third focuses on development of the GBM basin, which is now an international river system. These studies are a unique contribution to the science and art of water resource development from a highly respected expert. He has designed most of the major projects in the Ganga basin and continues to teach and conduct research at the international level.

International tensions around water are rising in many of the world's most volatile regions. The policy recipe pursued by the West, and imposed on governments elsewhere, is to pass control over water to private interests, which simply accelerates the cycle of inequality and deprivation. California, as well as China, South Africa, Mexico and countries on every continent already face a crisis. This book exposes the enormity of the problem, the dangers of the proposed "solution" and the alternative, which is to recognise access to water as a fundamental human right, not dependent on ability to pay.

This classic reference begins with a brief review of the origins and early history of cooling towers and finally brings together the variety of terms in the industry into a uniform system of terminology. Facts accumulated as a result of laboratory testing together with full-scale tests in the field provide
the basis for the methods described in the book. Provides easy to use combination of steps in which to incorporate the Merkel theory. English-American units of measure are used in the examples with metric equivalents shown in parentheses. Appendices contain tables of appropriate constants and conversion factors for use with SI. This guide is of great benefit to cooling tower users, operators and plant designers.

Desertification and land degradation are complex phenomena, and we need to understand their causes, consequences, and means to mitigate and combat their impact. Therefore, this book aims to explain the concept and characteristics of drylands, desert and desertification, land degradation, wastelands, and the concept of ecosystem services. It also discusses various types of processes of land degradations, their characteristics, physics and indicators along with mapping, monitoring and assessment of methods involved. Concept of Ocean Biological Deserts is discussed along with international and regional efforts towards combating land degradation and desertification. Key Features: * Provides all the aspect of desertification and land degradation at one place * Includes comprehensive methods to monitor different desertification/land degradation processes * Comprehensive overview of the mapping, monitoring and modelling techniques * Role of space borne data in identifying, monitoring and combating desertification is evaluated and reported with real case studies * Explains the concept of ocean biological deserts, their characteristics and mapping

The world's water resources are being tapped at an ever increasing rate, to the extent that sustainability and water quality are being compromised. This book provides accounts of the technology used for managing water resources to reduce risks. Besides controlling floods, overcoming droughts and reducing pollution, the reader will learn to plan and maintain hydraulic structures, and to appreciate the diverse demands on water, including those of the environment. The topics considered include hydrology and assessment of water resources; drought management and flood management tools; and the interaction between land use and water resources, including surface runoff, groundwater and water quality. The second half of the book focuses on water use, demand management and the infrastructure required to manage water. Consideration is also given to the tools needed for planning, including economics and computer modelling. This book is aimed at a postgraduate level, suitable for students in water engineering and science. It will also serve as a reference for practitioners concerned with water resources and water supply.

This book, which was first published in 1992 and then updated in 2007, provides a tool for dealing with the legal and institutional aspects of water resources management within national contexts and at the level of transboundary water resources. Like its two previous editions, it seeks to cover all aspects that need to be known in order to attain good water governance, but it provides updates concerning developments since 2007. These relate, inter alia, to the following: - the "greening" of water law, which calls for the progressive integration of environmental law principles into domestic and international water law; - the adoption, by the International Law Commission in 2008, of the Draft Articles on the Law of Transboundary Aquifers, and subsequent developments; - the emergence of the right to water as a self-standing human right; - the adoption of domestic water laws supporting integrated water resources management (IWRM) and enhanced public participation in planning and decision making; - the integration into these laws of tools facilitating adaptive water management as a response to climate variability and change; - progress in the implementation of EU law; - recent international agreements and judicial decisions; - efforts of regional organizations other than the EU to steer cooperation in the management of transboundary water resources and the harmonization of national laws; - institutional mechanisms for the management of transboundary water resources (surface and underground). Unique in its scope and nature, the book identifies the legal and institutional issues arising in connection with water resources management and provides guidelines for possible solutions in a manner accessible to a wide range of readers. Thus, it is a useful reference for lawyers and non-lawyers - engineers, hydrologists, hydrogeologists, economists, sociologists - dealing with water resources within government institutions, river basin commissions, international organizations, financing institutions and academic institutions, among other things, and also for students of disciplines related to water resources.

Nitrogen rich wastewaters (10-400 mg N L-1) are usually produced by municipal, industrial and agricultural wastes, such as effluents from anaerobic treatments. These represent a risk to the environment due to the high nutrient concentrations (nitrogen and phosphorous), which can cause eutrophication of water bodies, deteriorating the quality of the ecosystems. As a solution, the potential nitrogen removal capacity of a novel bio-treatment system, namely the Photo-Activated Sludge (PAS), which is composed of microalgae and bacteria consortia, is presented in this thesis. This novel bio-treatment is based on the symbiosis between microalgae, nitrifiers and heterotrophic bacteria (microalgal-bacterial consortia). Experimental work using photobioreactors for the cultivation of microalgae and bacteria under sequencing batch conditions showed that microalgal-bacterial consortia can remove ammonium 50% faster than solely microalgal consortia. The increase in ammonium removal rates was due to the action of nitrifying bacteria, supplied with oxygen produced by algae. Nitrification was the main ammonium removal mechanism within the microalgal-bacterial biomass, followed by algal uptake and nutrient requirements for bacterial growth. Carbon oxidation and denitrification were the main removal mechanisms for organic carbon. Hence, the role of algae within the microalgal-bacterial system is to provide oxygen to support the aerobic processes. The microalgal-bacterial system offers the possibility of reducing the hydraulic retention time, which can decrease the large area requirements often demanded by algal systems.

Contents:
Foreword. Acknowledgements. Chapter I: Basic Requirements for Optimization. 1.0 Introduction. 1.2 Personnel. 1.3 Management Structure. 1.4 Plant Maintenance. 1.5 Housekeeping. Chapter II: Assessing Plant Performance and Identifying Defects. 2.1 Observing Plant Operation. 2.2 Raw Water Intake 2.3 Raw Water Metering 2.4 Coagulent Handling. 2.5 Flocculation Systems. 2.6 Settling Basins. 2.7 Filters. 2.8 Disinfection. 2.9 Stabilizaion. 2.10 Checklist for Plant Review Chapter III: Water Analysis for Treatment Control. 3.1 Physical Contaminants. 3.2 Biological Variables. 3.3 Chemical Variables and Contamination. 3.4 Laboratory Analysis. Chapter IV: Improving Plants and their Operation. 4.1 Plant Records. 4.2 Raw Water Intake and Flow. 4.3 Rehabilitation of the Chemical Building. 4.4 Pretreatment Units. 4.5 Filter Rehabilitation. 4.6 Filter Operation. 4.7 Stabilization. Chapter V: Determining Design Parameters. 5.1 Introduction to Bench Scale Testing. 5.2 Design and Process Parameters. 5.3 Equipment and Laboratory Space. 5.4 Testing in the Laboratory for Conventional Treatment. 5.5 Testing in the Laboratory for Direct Filtration. 5.6 Sampling for Determinination of Treatment Plant Performance. 5.7 Pilot Plants. 5.8 Treatment Plant as a Pilot Plant. Chapter VI. Disinfection. 6.1 Choice of Process. 6.2 Health Risks of Chlorine. 6.3 Design of Chlorination Facilities. Chapter VII: Optimising and Upgrading Treatment Plants. 7.1 Applying New Technology. 7.2 Optimizing the Treatment Process and Plant Performance. 7.3 Design Information. Chapter VIII: Optimisation and Upgrading of a Plant from 100 ls-1 to 250 ls-1. 8.1 Assessment of Existing Plant. 8.2 Characteristics of the Upgraded Plant. 8.3 Inlet Chamber. 8.4 Initial Mixing of Coagulant and Raw Water. 8.5 Flocculation. 8.6 Distribution of Flocculated Water to Settling Basins. 8.7 Settling Basins. 8.8 Filters. 8.9 Summary. Chapter IX: Optimisation and Upgrading of a Plant from 1m3s-1 to 2.5 m3s-1. 9.1 Assessment of Existing Plant. 9.2 Modifications Required for Upgrading and Optimisation. 9.3 Design of Modifications. Chapter X: Optimisation and Upgrading of a Plant from 20 ls-1 to 50 ls-1 10.1 Assessment of Original Plant. 10.2 Plant performance. 10.3 Upgrading Parameters Determined by Jar Testing. 10.4 Design of Modifications for Upgrading and Optimization. Appendix I Sources of Further Information. Appendix II. Glossary of Terms. Index.

Having a robust drought monitoring system for Ethiopia is crucial to mitigate the adverse impacts of droughts. Yet, such monitoring system still lacks in Ethiopia, and in the Upper Blue Nile (UBN) basin in particular. Several drought indices exist to monitor drought, however, these indices are unable, individually, to provide concise information on the occurrence of meteorological, agricultural and hydrological droughts. A combined drought index (CDI) using several meteorological, agricultural and hydrological drought indices can indicate the occurrence of all drought types, and can provide information that facilitates the drought management decision-making process. This thesis proposes an impact-based combined drought index (CDI) and a regression prediction model of crop yield anomalies for the UBN basin. The impact-based CDI is defined as a drought index that optimally combines the information embedded in other drought indices for monitoring a certain impact of drought, i.e. crop yield for the UBN. The developed CDI and the regression model have shown to be effective in indicating historic drought events in UBN basin. The impact-based CDI could potentially be used in the future development of drought monitoring in the UBN basin and support decision making in order to mitigate adverse drought impacts.

The aim of this Ph.D. was to develop a technology for the remediation of seleniferous soils/sediments and to explore microbial reduction of selenium oxyanions under different respiration conditions and bioreactor configurations. Seleniferous soil collected from the wheat-grown agricultural land in Punjab (India) was characterized and its soil washing was optimized by varying parameters, where addition of oxidizing agents showed a maximum selenium removal efficiency. Aquatic plants, Lemna minor and Egeria densa were used to study phytoremediation of the selenium-rich soil leachate containing oxidizing agents. Additionally, migration of the soluble selenium fraction from the upper to the lower layers and its subsequent reduction and accumulation in the lower layers of the soil column was observed during soil flushing. Furthermore, the soil leachate containing selenium oxyanions obtained from soil washing was treated in a UASB reactor by varying the organic feed. Ex situ bioremediation of selenium oxyanions was studied under variable conditions. An aerobic bacterium (Delftia lacustris) capable of transforming selenate and selenite to elemental selenium was isolated and characterized. Anaerobic bioreduction of selenate coupled to methane oxidation was investigated in serum bottles and a biotrickling filter using marine sediment as inoculum. Finally, the effect of contamination of other chalcogen oxyanions (tellurium) on selenium bioreduction was studied in a continuous system (UASB reactor).

In 2017 four rivers in Aotearoa New Zealand, India, and Colombia were given the status of legal persons, and there was a recent attempt to extend these rights to the Colorado River in the USA. Understanding the implications of creating legal rights for rivers is an urgent challenge for both water resource management and environmental law. Giving rivers legal rights means the law can see rivers as legal persons, thus creating new legal rights which can then be enforced. When rivers are legally people, does that encourage collaboration and partnership between humans and rivers, or establish rivers as another competitor for scarce resources? To assess what it means to give rivers legal rights and legal personality, this book examines the form and function of environmental water managers (EWMs). These organisations have legal personality, and have been active in water resource management for over two decades. EWMs operate by acquiring water rights from irrigators in rivers where there is insufficient water to maintain ecological health. EWMs can compete with farmers for access to water, but they can also strengthen collaboration between traditionally divergent users of the aquatic environment, such as environmentalists, recreational fishers, hunters, farmers, and hydropower. This book explores how EWMs use the opportunities created by giving nature legal rights, such as the ability to participate in markets, enter contracts, hold property, and enforce those rights in court. However, examination of the EWMs unearths a crucial and unexpected paradox: giving legal rights to nature may increase its legal power, but in doing so it can weaken community support for protecting the environment in the first place. The book develops a new conceptual framework to identify the multiple constructions of the environment in law, and how these constructions can interact to generate these unexpected outcomes. It explores EWMs in the USA and Australia as examples, and assesses the implications of creating legal rights for rivers for water governance. Lessons from the EWMs, as well as early lessons from the new 'river persons,' show how to use the law to improve river protection and how to begin to mitigate the problems of the paradox.

The enhanced biological removal of phosphorus (EBPR) is a popular process due to high removal efficiency, low operational costs, and the possibility of phosphorus recovery. Nevertheless, the stability of the EBPR depends on different factors such as: temperature, pH, and the presence of toxic compounds. While extensive studies have researched the effects of temperature and pH on EBPR systems, little is known about the effects of different toxic compounds on EBPR. For example, sulphide has shown to inhibit different microbial activities in the WWTP, but the knowledge about its effects on EBPR is limited. Whereas the sulphide generated in the sewage can cause a shock effect on EBPR, the continuously exposure to sulphide potentially generated in WWTP can cause the acclimatization and adaptation of the biomass. This research suggests that sulphate reducing bacteria can proliferate in WWTP, as they are reversibly inhibited by the recirculation of sludge through anaerobic-anoxic-oxic conditions. The research enhances the understanding of the effect of sulphide on the anaerobic-oxic metabolism of PAO. It suggests that the filamentous bacteria Thiothrix caldifontis could play an important role in the biological removal of phosphorus. It questions the ability of PAO to generate energy from nitrate respiration and its use for the anoxic phosphorus uptake. Thus, the results obtained in this research can be used to understand the stability of the EBPR process under anaerobic-anoxic-oxic conditions, especially when exposed to the presence of sulphide.

Quantitative research with respect to the combination of engineering and socialcultural- religious aspects based on the Tri Hita Karana philosophy in Subak irrigation schemes is original in the field of land and water development. A scenario analysis needs a good and careful system approach. Based on a Generic Algorithm the RIBASIM model was applied using the dependable 80% of discharge and shifting the start of land preparation. The results provide evidence that the cropping pattern of the fifth scenario results in an overall optimal agriculture production of the Subak schemes. The recoverable flow considered in the river basin scheme model plays an important role in the optimisation. Nevertheless, if a normal hydro-climate occurs, the other scenarios, especially the first scenario, can be applied as well. When the indigenous knowledge of farmers is compromised with present day knowledge of agricultural and technological developments, capability of these farmers increases, thus reflects the applicability of the Tri Hita Karana philosophy on harmony among people and harmony among people and nature.

The Congress "Arsenic in the Environment" offers an international, multi- and interdisciplinary discussion platform for research aimed towards a holistic solution to the problem posed by the environmental toxin arsenic, with considerable societal impact. The congress has focused on cutting edge and breakthrough research in physical, chemical, toxicological, medical, agricultural and other specific issues on arsenic across a broader environmental realm. The Congress "Arsenic in the Environment" was first organized in Mexico City (As2006) followed by As2008 in Valencia, Spain, As2010 in Tainan, Taiwan and As2012 in Cairns, Australia. The 5th International Congress As2014 was held May 11-16, 2014 in Buenos Aires, Argentina and entitled One Century of the Discovery of Arsenicosis in Latin America (1914-2014). The session topics comprised: Theme 1: Arsenic in environmental matrices (air, water and soil) Theme 2: Arsenic in food Theme 3: Arsenic and health Theme 4: Removal technologies Theme 5: Mitigation management and policy Hosting this Congress in Argentina was especially relevant because 2014, marks 100 years since the discovery of the disease Hidroarsenicismo Cronico Regional Endemico (HACRE) or arsenicosis by Dr. Goyenechea and Dr. Ayerza in the city of Bell Ville, Province of Cordoba, Argentina. Dr. Ayerza was the first person to relate skin disorders to the consumption of groundwater with high concentrations of arsenic. It is estimated that more than 14 million people in Latin America are at risk, of whom nearly 4 million are exposed to drinking water with high arsenic concentration in Argentina, and further in Chile, El Salvador, Mexico, Nicaragua and Peru. A vast area of the Chaco-Pampean Plain in Argentina, mostly in the semi-arid regions, is affected not only by arsenic exposure from drinking water but also through other exposure pathways, e.g. through food and other dietary intake. The Congress has gathered professionals involved in different segments of interdisciplinary research in an open forum, and strengthens relations between academia, industry, research laboratories, government agencies and the private sector to share an optimal atmosphere for exchange of knowledge, discoveries and discussions about the problem of arsenic in the environment.

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.

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.

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.