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1.
Serving the world population with adequate drinking water and sanitation is an important prerequisite, not only to hygienic safety, but to prosperity and political stability as well, and will foster the adaptive capacity of the societies in the developing countries and beyond. To avoid hygienic and political disasters impacting the world economy, investment in water supply and sanitation must urgently be made. Whether the classical system of urban water supply and sanitation is appropriate to satisfy the needs of the developing world, however, and whether this system meets the general criteria of sustainability is questionable. The costs and the time needed for installation of sewers and wastewater treatment plants are tremendous. In water shortage areas, the amount of tap water required to transport pollutants to the treatment plant is hardly affordable. Recovery and re-introduction of valuable substances, including water, into the urban cycle of materials is impossible because of mixing and dilution effects inherent in the system. Decentralized water and wastewater management should be seriously taken into account as an alternative. Source separation of specific fractions of domestic and industrial wastewater, separate treatment of these fractions and recovery of water and raw materials including fertilizer and energy are the main characteristics of modern high-tech on-site treatment/reuse systems. Mass production of the key components of the system could reduce the costs of the treatment units to a reasonable level. On-site units could be installed independently of the development stage of the urban sewer system. In conjunction with building new housing complexes a stepwise improvement of the hygienic situation in urban and peri-urban areas could be achieved, therefore. Remote control of the satellite systems using modern telecommunication methods would allow reliable operation, and comfort for the users. Intensive research is required, however, to develop this system and bring it to a standard allowing efficient application worldwide.  相似文献   

2.
Abstract

The development over time of the water supply and sanitation sectors in four countries is analyzed to reveal the changing role of the private sector. In some cases, local, small-scale private water supply and sanitation systems have been able to develop progressively into large-scale official systems, which may later be privatized. In other cases, foreign capital has been more significant in the development of modern water supply and sanitation systems, particularly where privatization has occurred much earlier in the national development process. In much of the developing world, domestic water supply and sanitation is dominated not by the official water supply and sanitation companies but by independent operators who function without subsidies but with enormous variability in terms of quality of service and prices offered. However, they are constrained generally by the absence of appropriate institutional and legal frameworks, including the lack of independent regulatory authorities. There is a need, where appropriate, to continue to encourage large-scale private sector involvement in the official water supply sectors of the developing world. At the same time though, it is only by promoting policies that also further the development (where appropriate) of the independent water supply and sanitation providers that access to water supply and sanitation services can be maximized since better use of local resources in many developing countries, both local human resources and capital, provide a key means for improving access to water supply and sanitation.  相似文献   

3.
The basic concept of collecting domestic liquid waste in water-borne sewer systems goes back more than 100 years and became in the last century the conventional approach to sanitation in urban areas. Over the years, these sewage disposal systems had to be successively upgraded by additional sewage treatment plants increasing investment, operating and maintenance costs. Although these conventional sanitation systems could improve significantly the public health situation in those countries who could afford to install and operate them, it is highly questionable, if they are economically and ecologically sustainable. The large number of people in the developing world who still do not have access to adequate sanitation is a clear indication that the conventional approach to sanitation is not adapted to the socio-economic condition prevailing in most countries of Africa, Asia and Latin America. Advanced environmental sanitation is aiming not only to protect public health and the integrity of aquatic ecosystems but also to conserve precious freshwater and non-renewable resources. The Bellagio Principles and the Household Centred Environmental Sanitation Approach (HCES) are suggested as guiding principles and a new approach for planing and designing advanced (sustainable) environmental sanitation systems.  相似文献   

4.
The provision of adequate water supply and sanitation to the rapidly growing urban populations is increasingly becoming a problem for governments throughout the world. The continuing expansion of the numbers of people in cities who need water and sanitation services form a continuous pressure to either invest in additional production capacity or to stretch the available supplies to serve more people. Due to rapid increase in population growth in the Yobe State north of Nigeria, there is a shortage in the water supply to Damaturu city the capital of the state and surrounding villages. At the present the total water supply is about 10,000 m3/day abstracted form the shallow alluvial groundwater aquifer using 29 production wells. Due to the expected increase in water demand and the limited potentiality of shallow aquifer system, other deep aquifers were explored and investigated to evaluate their potentiality for future water demand. Vertical Electrical Sounding Method was used for the geophysical survey of the study area. Groundwater flow model was developed and calibrated against the historical information. Three wellfields were designed to provide Damaturu city and surrounding villages with the required water. The calibrated model has been used to evaluate the aquifer potentiality and the effect of future withdrawals on the deep aquifer system. It was found that the aquifer system within the study area consists of two main layers. The upper layer is the Chad formation comprises an alluvial sand and gravel with intercalation of thin sility clay layers. The second layer is Keri-Keri formation consists of sandstone formation which is not explored before. During this study the Kerri-Kerri aquifer system was investigated as an alternative source for groundwater for future demand. The study presents an integrated groundwater resources management strategy for present and future water supply for rural communities.  相似文献   

5.
Increasing access to safe drinking water, adequate sanitation services and improving water resources management are central to the basic right of every human being. Egypt has set an ambitious water agenda in response to the many challenges facing the country and the people. It has successfully met the World Summit for Sustainable Development (WSSD) water targets by developing and implementing a national integrated water resources management plan during the post 2017-period. Egypt has also taken several measures to meet the Millennium Development Goals (MDG) targets for drinking water and sanitation. It has successfully proceeded in supplying nearly the whole population with access to drinking water, whereas sanitation coverage heavily favours urban areas and only a small fraction of rural areas. This paper aims to shed some light on the efforts exerted by the government of Egypt for equitable and sustainable management of its water resources that benefit both individuals and the society at large.  相似文献   

6.
Abstract

Hong Kong, now a Special Administrative Region of China, is a very special and unique place in the world. Although the territory is located in the humid subtropics, local water resources are very limited because of its geographical setting and physical environment. Hong Kong's urban water supply has its uniqueness and has gone through a history of developing local resources and transferring water from the East River (Dongjiang) basin in mainland China over the past half century. This paper aims to present the experience and challenges in developing water supplies and managing water resources in Hong Kong. First, the availability of local water resources is evaluated in the context of the territory's geographical setting. Second, the approaches adopted for developing urban water supply from local resources and more importantly, by making use of water imported from the Dongjiang, are presented and reviewed. Finally, a number of sustainability issues in Hong Kong's urban water supply are addressed with an emphasis on the problems and prospect of the Dongjiang water resources in the future  相似文献   

7.
This paper presents the existing philosophy, approach, criteria and delivery of environmental engineering education (E3) for developing countries. In general, environmental engineering is being taught in almost all major universities in developing countries, mostly under civil engineering degree programmes. There is an urgent need to address specific inputs that are particularly important for developing countries with respect to the reality of urbanisation and industrialisation. The main component of E3 in the near future will remain on basic sanitation in most developing countries, with special emphasis on the consumer-demand approach. In order to substantially overcome environmental problems in developing countries, E3 should include integrated urban water management, sustainable sanitation, appropriate technology, cleaner production, wastewater minimisation and financial framework.  相似文献   

8.
Ziad A. Mimi  Amer Marei 《国际水》2013,38(2):219-224
Abstract

The present problems that are related to water and sanitation in Palestine are many and varied, and the disparity between water supply and demand is growing with time due to the rapid population growth and aridity. Desalination has the potential to supply unlimited quantities of high-quality freshwater to Palestinian Communities. On the other hand, the situation of the sewerage system in the cities is extremely critical, and there are no sewerage systems in the rural areas. There is an urgent need for substantial improvements and extensions to the sewerage systems and treatment plants. The available funds for the Palestinian Water Authority (PWA) and other municipalities to implement wastewater and desalination projects are limited. As a result, it is important to fully explore the use of public-private partnerships that utilize sector resources to finance such projects. The objective of this study is to understand incentives for privatization of water supply and sanitation services, with more emphasis on the households' Affordability and Willingness-to-Pay (AWTP) for improved water and sanitation services. The results show that people in Palestine bear the burden of high water supply and sanitation costs. Privatization of the water and sanitation sector will guarantee sustainable development of these sectors under limited financial resources and dependency on external funds.  相似文献   

9.
Water Management for a Megacity: National Capital Territory of Delhi   总被引:1,自引:0,他引:1  
Urban and regional demand for freshwater in National Capital Territory of Delhi has grown significantly over the last few decades. The National Capital Territory, Delhi is one of the most rapidly growing urban centers of the world, with a population of about 15 million people, a high rate of immigration and numerous illegal settlements. In order to meet the increasing water demand, the government is focused almost exclusively on supply management and engineering solutions, which have resulted in investments of hundreds of millions of Rupees. Environmental, economic and social policies associated with water management are largely inadequate and insufficient, which is resulting in increasing deterioration in the environment, health and socio-economic conditions of a population living in one of the largest urban agglomerations of the world. Surprisingly, however, no long-term strategies on demand-management, reuse, conservation, and improved water-management practices have been developed so far. The aim of this paper is to provide an overview of the urban water use with a view to enhance the understanding of the factors influencing urban water demand for residential, commercial and industrial sectors in National Capital Territory of Delhi. The analysis indicates an urgent need to radically improve the current water supply and wastewater management practices to become sustainable. Other measures such as public education and information/awareness will be necessary to achieve desired rationalization in water consumption, especially in the residential and commercial sectors.  相似文献   

10.
ABSTRACT

External support agencies and national governments are advocating community management of rural drinking water supplies and sanitation facilities as an appropriate and realistic way ofguaranteeing the long-term sustainability of systems in developing countries. Experience with community managed rural water supplies in the developed world can provide useful insights and guidance for the conceptualization, planning, and implementation of community managed water projects. Lessons from a successful water supply program in Western Canada suggest that a sustainable community managed water supply project must be demand driven, that the implementing agency provide an enabling environment, and that beneficiaries be legally empowered to assume ownership and responsibility for the completed systems.  相似文献   

11.
During the last decades, significant subsidies have been allocated to government-owned water and sewerage enterprises in developing countries. However, water and sewerage coverage is still far from desirable and the poor are particularly affected by the shortage of these services. The truth is that a considerable part of these subsidies have been used up to build huge infrastructure works that would make some construction firms happy, while often decreasing the service costs for the richer. The costs associated of delivering water and sanitation services to the poor are significantly higher, as they often live in slums or irregular urban developments without urban infrastructure. It is possible, and desirable, to improve government's effectiveness through the use of appropriate economic incentives. The Brazilian River Basin Pollution Abatement Program, based on the "output-based aid" concept, is a good example of how this can be achieved. The Program is a success story that shows that the quality of expenditures on sanitation can be considerably improved if governments of developing countries refrain from contracting sanitation infrastructure works and start paying for results, not for promises.  相似文献   

12.
Water sensitive urban developments are designed with integrated urban water management concepts and water sensitive urban design measures. The initiatives that may be included are the substitution of imported drinking water with alternative sources using a fit-for-purpose approach and structural and non-structural measures for the source control of stormwater. A water sensitive approach to urban development can help in achieving sustainability objectives by minimising disturbance to ecological and hydrological processes, and also relieve stress on conventional water systems. Water sensitive urban developments remain novel in comparison with conventional approaches, so the understanding and knowledge of the systems in regards to their planning; design; implementation; operation and maintenance; health impacts and environmental impacts is still developing and thus the mainstream uptake of these approaches faces many challenges. A study has been conducted to understand these challenges through a detailed literature review, investigating a large number of local greenfield and infill developments, and conducting extensive consultation with water professionals. This research has identified the social, economic, political, institutional and technological challenges faced in implementing water sensitive urban design in greenfield and infill developments. The research found in particular that there is the need for long-term monitoring studies of water sensitive urban developments. This monitoring is important to validate the performance of novel approaches implemented and improve associated guidelines, standards, and regulatory and governance frameworks, which can lead to mainstream acceptance of water sensitive urban development approaches. The dissemination of this research will help generate awareness among water professionals, water utilities, developers, planners and regulators of the research challenges to be addressed in order to achieve more mainstream acceptance of water sensitive approaches to urban development. This study is based on existing water sensitive urban developments in Australia, however, the methodology adopted in investigating impediments to the uptake of these developments can be applied globally. It is hoped that insights from this study will benefit water professionals in other countries where there is also a move towards water sensitive urban development.  相似文献   

13.
The article outlines the dynamics of the privatization of water supply and sanitation services in Saudi Arabia. It also gives a summary of the projected requirements of desalination plants' capacity and the estimated capital investment needed for water supply and sanitation services. It gives a summary of public and private initiatives to privatize water services in Saudi Arabia.  相似文献   

14.
Sustainable sludge management in developing countries.   总被引:1,自引:0,他引:1  
Worldwide, unsanitary conditions are responsible for more than three million deaths annually. One of the reasons is the low level of sanitation in developing countries. Particularly, sludge from these regions has a high parasite concentration and low heavy metal content even though the available information is limited. Different issues needed to achieve a sustainable sludge management in developing nations are analysed. Based on this analysis some conclusions arise: sludge management plays an important role in sanitation programs by helping reduce health problems and associated risks; investments in sanitation should consider sludge management within the overall projects; the main restriction for reusing sludge is the high microbial concentration, which requires a science-based decision on the treatment process, while heavy metals are generally low; adequate sludge management needs the commitment of those sectors involved in the development and enforcement of the regulations as well as those that are directly related to its generation, treatment, reuse or disposal; current regulations have followed different approaches, based mainly on local conditions, but they favour sludge reuse to fight problems like soil degradation, reduced crop production, and the increased use of inorganic fertilizers. This paper summarises an overview of these issues.  相似文献   

15.
This paper deals with the major problems related to water management in the urban areas of developing countries. Increasing human activities within the urban areas create water pollution which causes degradation of water quality in rivers and aquifers. Poor urban infrastructure obstructs economic growth and development. Inadequate access to water and sanitation causes degradation of the environment and human health in urban areas. Some of these problems and the major management issues for Hanoi are discussed in this paper. A general planning framework for the water sector to meet the environmental challenges of the next decade for sustainable economic growth and development of the city is outlined.  相似文献   

16.
Abstract

This paper describes the recently developed ‘Guidelines for the design and control of intermittent water distribution systems’. These guidelines outline a new approach to the design of urban water distribution systems for developing countries in order to maintain adequate and equitable supplies under the common conditions of water resource shortage. The guidelines are novel in that they recognise the reality of intermittent supply and hence provide new methods of analysis and design, appropriate for such systems. Design objectives specifically tailored to intermittent systems are developed and drive the design process. These objectives are expressed in terms of equity in supply, adequate pressure at water connections and duration or time of supply that are convenient to the consumers. The modifications required to model such systems have been incorporated into a new network analysis simulation tool coupled with an optimal design tool.  相似文献   

17.
Abstract

This paper characterizes present challenges in water management worldwide and explores interdependencies between present technologies in water supply, sanitation, organic waste management, agriculture, and food production. The purpose of this discussion is to increase the sensitivity of readers to the connections between actions planned or already taken in different sectors that are usually only marginally considered by the scientific water community. A related purpose is to show how present problems may be turned into opportunities provided that actions in water management, sanitation provision, solid waste management, agriculture and food production are seen and approached as highly interdependent. An overriding premise of the discussions is that the scientific community of water scientists has a crucial role to play in future actions towards securing not only access to water and decent sanitation to everybody but also in global struggle to deliver enough food for a growing world population.  相似文献   

18.
Modern growing society is mainly driven by oils and may be designated "petroleum civilisation". However, the basic energy used to drive the global ecosystem is solar radiation. The amount of fossil energy consumption is minimal in the whole global energy balance. Economic growth is mainly controlled by the fossil (commercial) energy consumption rate in urban areas. Water and sanitation systems are bridging economical activities and global ecosystems. Therefore, vast amounts of high entropy solar energy should always be taken into account in the water industry. Only in urban/industrial areas where most of the GDP is earned, are commercial energy driven systems inevitably introduced with maximum effort for energy saving. A water district concept to ensure appropriate quality use with the least deterioration of the environment is proposed. In other areas, decentralised water and sanitation systems driven on soft energy paths would be recommended. A process and system designed on a high entropy energy system would be the foundation for a future urban metabolic system revolution for when oil-based energy become scarce.  相似文献   

19.
This article synthesizes the literature on historical and emerging institutional arrangements for urban water supply in Sub-Saharan Africa to highlight successes, drawbacks, and opportunities for improving future water access. It traces the influence of decades-long global water initiatives on urban water-policy reforms in the region and reviews evidence on emerging community self-help and partnership models. Finally, it discusses the merits, targets and potential of Sustainable Development Goal 6 to improve urban water access in the region. The findings suggest that improving urban water supply in Sub-Saharan Africa requires innovative governance and institutional arrangements that blend the strengths of public, private and community-based water supply models.  相似文献   

20.
In response to a range of contemporary urban water challenges, there is an increasingly urgent need to change the way water is used in our cities. In Australia, the 'Security through Diversity' policy has been introduced in a number of cities to help facilitate a shift towards sustainable urban water management. This qualitative case study research investigated the interpretation and implementation of this radically different urban water policy approach across the case study cities of Perth and Melbourne. To focus the research and allow for more reliable comparative analysis across the cities, the introduction of desalination and permanent water saving rules as new initiatives in these cities were of particular interest. The research results are drawn from a synthesis of over 65 semi-structured interviews with senior urban water practitioners in the case study cities, and a content analysis of key policy and guidance documents, as well as organizational literature where available. The key finding of this research was that because of an entrenched technological paradigm, and the difficulty in breaking this pattern of lock-in, practitioners are currently interpreting and implementing Security through Diversity in a way that does not fully realise the potential of this strategy. More specifically the interview results revealed that the urban water practitioner community believed that the introduction of seawater desalination would discharge their city's responsibility for achieving Security through Diversity and that demand management initiatives, while nice, are not essential to this policy position. Interestingly, despite context evidence to the contrary, the practitioners believed supply and demand planning to be an integrated practice within their city. The paper concludes by offering some recommendations to facilitate a more comprehensive implementation of Security through Diversity and outlines areas for possible future research.  相似文献   

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