Hydrology and Hydraulics in Planning and Operation of Water Resources Systems

ABSTRACT

A number of water supply schemes in developing countries have been observed to fail to yield water at the design capacity rates well before the elapse of the design period. Such failures frustrate the efforts of a nation in its water supply development programmes.

In this paper the causes of failures o f some typical components o f a water supply scheme have been discussed citing case studies from Tanzania in East Africa. It is observed that the elements o f design and maintenance are largely responsible for the failures o f water supply schemes.

Rehabilitation of failing water supply schemes in developing countries can substantially increase the number of people served with safe and adequate water supply. Clear national policies and adequate budgetary provision are required for successful implementation of water supply projects.     

The Perception of Water Quality Among Rural Communities in South-Western Nigeria: Lesson for Planners

ABSTRACT

“Clean water for all” is one of the goals of the UN International Drinking Supply and Sanitation Decade 1981–90. This goal to be accomplished, requires a level of governmental investment which is difficult to reach in many developing countries. This is particularly so of Nigeria where a vast majority of rural people is yet to benefit from improved water supply and where the level of priority accorded domestic water supply is dismally low, with some states devoting just about 1% of their total capital expenditure to water supply provision.

At the same time, there is evidence that the rural people in many places, aware of the advantages of good water sources and the disadvantages of bad ones, show preferences for and undertake development programmes connected with good quality water supply: this is here exemplified by three rural communities in southwestern Nigeria. Not only are these people knowledgeable about water quality and its relationship with health, they are also eager to seize any feasible opportunities to improve their water supply situation.

It is argued that rather than rely on gigantic time-consuming, capital intensive and difficult to maintain schemes, as we have presently with government projects, more modest ones within the competence of the rural communities should be encouraged.     

Informal water markets and community management in peri-urban Luanda,Angola

ABSTRACT

The majority of Angola’s peri-urban population still rely on informal mechanisms for water supply. This water is expensive and of poor quality, representing a significant household expenditure for the urban poor. The article uses qualitative tools and tracking of the supply chain to analyze the scope of the informal water economy in Luanda. Marketing water at the local household level involves significant trading in social capital. A financially sustainable model of community water management that builds on this neighbourhood social capital has been adopted by the government for implementation across the country.     

THE BLUE NILE: POTENTIAL FOR CONFLICT AND ALTERNATIVES FOR MEETING FUTURE DEMANDS

ABSTRACT

Despite nearly a century of water regulation projects on the Nile Basin, today Egypt faces a genuine crisis with respect to water supply. The crisis has been brought on by a combination of drought and greatly increased usage by all riparian nations along the Nile. It is highly probable that Egypt will need to search for new sources of water, reallocate existing water supply and reduce demand simultaneously in order to stave off major water shortfalls. It is unlikely that these measures can be accomplished without both internal and external conflict. This paper describes the current state of water supply and usage in Egypt. Further we examine potential sources of conflict over water allocation decisions. Finally, the paper presents a method for evaluating alternative strategies that could be implemented by Egypt to avoid future conflict.     

Intermittent Water Supply under Water Scarcity Situations

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.     

Colonizing rural waters: the politics of hydro-territorial transformation in the Guadalhorce Valley,Málaga,Spain

ABSTRACT

This paper explores how, historically, the utopian thinking built into Spain’s water policies has legitimized profound transformations of the Guadalhorce Valley’s hydro-social territory (in Málaga), also justifying water transfers from rural to urban areas. It analyzes how the ‘regenerationist hydraulic utopia’ has been materialized through different ‘governmentality strategies’. This intensified during Francisco Franco’s dictatorship, decaying gradually into dystopias that, to this day, express profound socio-environmental impacts: dispossession, displacement, uprooting and breaking up local water governance institutions and practices. Meanwhile, the urban and tourism industries in Málaga have been strengthened by giving them priority for water supply.     

Water markets as coupled infrastructure systems: comparing the development of water rights and water markets in Heihe,Shiyang and Yellow Rivers

ABSTRACT

A Coupled Infrastructure Systems perspective is applied to three cases in north-western China to explain how and why water rights systems and water markets have changed since 1949. The evolution of water rights systems has been shaped by periods of water-supply projects and periods that emphasized regulatory and institutional measures to manage water resources. We argue that water supply infrastructure and water markets have been developed not in sequence but in parallel. The development of water diversion projects and nationwide market-oriented water allocation reform programmes will continue to co-evolve in the future as part of complex coupled infrastructure systems.     

The Virtual Water Metaphor Enhances Policy Discussions Regarding Scarce Resources

Abstract

In a recent issue of Water International, three authors discuss their views of the virtual water metaphor that is used to describe the water embedded in crops that are traded in international markets. The term ‘virtual water’ was created originally to gain the attention of public officials responsible for choosing policies that influence water use in arid regions. Over time, both the terminology and the scope of the virtual water metaphor have been extended beyond the original purpose. This paper supports the view that the virtual water metaphor is helpful in encouraging public officials to consider the scarcity value (opportunity cost) of water when designing policies that influence water use. The paper proposes, also, that the policy relevance of the virtual water metaphor is found primarily in its application to issues regarding the supply of agricultural products, rather than demand. The distinction between supply and demand issues and the potential value of the virtual water metaphor in policy discussions regarding supply are demonstrated using three examples of water allocation decisions, described within the framework of economic optimization. The examples include wheat production in Saudi Arabia and the production of sudangrass and ethanol in the United States.     

Integrated Evaluation of Water Quality and Quantity of the Yellow River

Abstract

This study presents an integrated water quantity and quality management method for the entire Yellow River system where the eco-environment has been deteriorating and water quantity is very scarce. The supply and demand of water resources has been investigated. The integration of the concepts of water resources functional capacity and water resources functional deficit have been put forward, and their characteristics have been analyzed. The results, based on 1997 to 1999 data, indicate that approximately 39 percent of the total river length was of excellent to good quality, 26 percent was moderate, and 35 percent was poor to very poor. The total natural runoffs of the river were 31.8, 43.9, and 43.4 billion m3, and about 94, 65, and 71 percent of them were withdrawn for agricultural, industrial, and domestic uses in 1997, 1998, and 1999, respectively. The total water resources availabilities were 21.1, 28.8, and 29.2 billion m3 occupying about 66, 66, and 67 percent of the total runoffs in 1997, 1998, and 1999, respectively. From 1997 to 1999, the river could provide only 53 percent (on average) of the total water resources demand for the uses and discharge to the Bohai Sea; about 57 percent of the water deficiency resulted from pollution and 43 percent from quantity deficit. For the main pollution parameter (COD _Mn ), the averages of water resources functional capacity and deficit were 29,571.54 and 199.70 kg, respectively; for NH ₄-N, the averages of water resources functional capacity and deficit were 3774.26 and 113.08 kg, respectively. These demonstrated that the influence of NH ₄-N on water resources availability was more than that of COD _Mn and that the functional capacity was much higher than functional deficit, suggesting that the actual water quality was mostly better than the required one for water supply functions.     

An Investigation into the Use of Water by Portuguese Industry

ABSTRACT

The continuous increase in water demand for various uses underlines the importance of supply problems in the general context of water resources management.

In this domain it would clearly be useful to collect and make available all the data currently stored on different paper supports and kept by several regional agencies. This would provide an immediate overview of tbe resources, and also permit forecasting the future demand for tbe various utilizations.

This paper describes a project involving a database to be used for groundwater resources management, conceived not only as a support for research activity, but also as a contribution to developing new and more efficient managementprocedures. The database has been designed to be used on a personal computer, with software readily available on the market.     

Changing Ownership Structures in the Water Supply and Sanitation Sector

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.     

The water footprint challenge for water resources management in Chilean arid zones

ABSTRACT

The water footprint concept is difficult to apply to water-shortage conditions because of private management and variability in the water balance. Chilean water law stipulates that water allocation depends on water rights and private organization criteria, according to the basin water supply and not necessarily crop irrigation demand, crop yield or irrigation technology. This paper explores the resultant complications.     

Factors Influencing Per Capita Water Consumption In Urban Areas Of Developing Countries And Their Implications For Management,With Special Reference To The Khartoum Metropolitan Area

ABSRTACT

The fast growing population in Third World countries and the limited physical resources in rural areas have led to the dramatic expansion of the urban areas of these countries. It is now recognized that when planning for the development of these areas, early consideration must be given to the difficulties and cost of providing potable water equitably to all users. Detailed studies are necessary for particular situations so as to provide a basis for better management practices.

Khartoum, a growing urban area in Sudan, has been chosen as a case study. A proposed framework and technique of analysis is shown. Factors influencingper capita consumption are correlated and mathematical models have been generated for the two distinct classifictions of consumers: (1) consumers with piped supply and (2) consumers obtaining water from water vendors or from standpipes (squatter settlements).

The most significant factors affecting the consumption appear in the fitted equations. Of these factors, the number of occupants in the household influences the per capita consumption but at a decreasing rate. Price has a significant impact on demand: price elasticities of about -0.60 and -0.78 are obtained for households with piped connections and squatter areas respectively. Water utility authorities can use price as a tool to ration or discourage water consumption in the piped connection households and to increase the rate of consumption in the squatter areas.     

The energy trade-offs of adapting to a water-scarce future: case study of Los Angeles

Abstract

Increasing water competition, population growth and global climate change will intensify the tension between water and energy resources in arid climates of the world, since energy costs underscore the challenges facing water security in dry regions. In few places is the tension between water and energy resources more pronounced than in Los Angeles, California. This article analyzes the city’s current water supply and estimates its future energy requirements based on water supply projections from the Los Angeles Department of Water and Power. Results suggest that while increasing local water management strategies could reduce the future energy intensity of the water supply, an increased reliance on water transfers could worsen its future energy intensity.     

Bacteriological Quality of Rainwater in Roof and Ground Catchment Systems in Botswana

ABSTRACT

Bacteriological analyses were conducted on water samples from 13 roof tanks and 8 ground catchment tanks in Botswana in 1983. The results show that rainwater collected from corrugated iron roofs and stored in covered tanks is of high quality compared with traditional water sources and could provide a safe drinking water supply. The results for the ground catchment tanks, however, indicated that the water posed a serious health hazard. This is significant since several hundred ground tanks are already being used to provide water for other things besides human consumption. Since more ground tanks are planned both in Botswana and elsewhere in Africa the fencing of the catchment area and the use of simple sand and charcoal filters are recommended as the most practical means of insuring improved water quality in ground tanks.     

Global Water Demand and Supply Projections

Abstract

This paper presents a modeling approach for projections of water demand and supply for domestic, industrial, livestock, and irrigation at the basin or country level in a global scope. Particular emphasis is put on simulating water availability for crops taking into account total renewable water, non-irrigation water demand, water supply infrastructure, and economic and environmental policies at the basin or country level. This paper focuses on concepts and methodology involved in the modeling exercise. Data assessment and results are presented in a companion paper (Rosegrant and Cai, 2002).     

Energy for freshwater supply,use and disposal in the Netherlands: a case study of Dutch households

Abstract

This study presents energy requirements for Dutch household water: 10.2 GJ per capita per year, which includes 9.3 GJ (92%) for heating water, 0.6 GJ (6%) for water supply, and 0.2 GJ for wastewater treatment (2%). The top three energy consumers include shower water (58%), dishwasher water (9%) and washing machine water (8%). The Netherlands, a water-abundant country, expends far more energy to heat water for households than to supply municipal water, or to treat and dispose of wastewater. Policies to make water chains more sustainable should focus on use, rather than supply and disposal.     

The exposure of a fresh fruit and vegetable supply chain to global water-related risks

ABSTRACT

We have combined estimates of the UK’s supply of fresh fruit and vegetables (1996 – 2015) with estimates of water requirements and water scarcity in producing countries, to identify where the supply is exposed to physical, regulatory and reputational water risks and how this has changed over time. Some 76% of the freshwater consumed in the supply of fresh fruit and vegetables to the UK is withdrawn overseas. The supply chain is particularly exposed to water risks in Spain, Egypt, South Africa, Chile, Morocco, Israel and Peru. Exposure has increased over time.     

Executive Summary—Community Water Supply: The Handpump Option

An estimated 1,800 million people need improved water supplies in the fifteen years to the end of the century, if developing countries are to reach the target of full coverage. The first half of the International Drinking Water Supply and Sanitation Decade (1981–1990) has seen increases in the percentages of the rural population with access to safe water supplies, but only in Asia has the pace been quick enough to envisage a target of essentiahy full coverage by the end of the century (ten years later than the original Decade goals). In Africa, present progress rates would leave half of the rural population still without safe water in the year 2000, while in Latin America, it may be ten years into the next century before full coverage is achieved unless progress improves dramatically.

Accelerated progress is hampered by financial and technical resource constraints faced by many developing countries, and the problem is aggravated by the growing number of completed projects which are broken down and abandoned, or functioning much below capacity. Attempts to increase the pace of providing improved community water supplies have often been frustrated because the technology used has proved impossible to sustain in village conditions.

To make a lasting impact on the urgent needs, community water supply (CWS) strategies must be based on sustainable and replicable programs, and must take account of the pace at which resource constraints can be overcome. Human resource development programs take time to produce results, and institutional changes can only be accomplished gradually.     

Progress in ecological and environmental water requirements research and applications in China

Abstract:

With economic development, as well as population growth, the conflict between water supply and demand has become more and more acute in China, and it has been aggravated further by the irrational utilization of water resources. As a result, the deterioration and destruction of the eco‐environment have become increasingly serious. In order to effectively protect ecosystems and improve their ecological conditions, many studies on ecological and environmental water requirements (EEWR) have been carried out in China. In this paper, the concept and characteristics of EEWR are addressed, and the main advances of EEWR research and applications in China are summarized in four types of systems including studies on rivers, vegetation, lakes and wetlands, and groundwater. In conclusion, issues necessary to be studied further in the future are put forward.