Developing World Water [antikvár]

INTRODUCTION SINCE WEDC compiled the first volume of Developing World Water we have passed the mid-point of the International Drinking Water Supply and Sanitation Decade. The United Nations General Assembly and many international and national committees have reviewed the situation, assessing what has been achieved in the first half of the Decade and what remains to be done. Two significant international conferences have focussed on the theme of mid-Decade assessment. The 12th WEDC Conference met within a week of the Decade mid-point in the centre of Calcutta, a megacity which contains a microcosm of developing countries' water supply and sanitation problems. Later, London was the venue for the World Water '86 conference. These assessments reveal the magnitude of the tasks remaining before all the world's people have acceptable water supplies and sanitation. The year 1990 will mark the end of the Decade, but by no means the end of the need for strenuous efforts to provide and improve the supply of safe drinking water and the provision of adequate sanitation. Most of the people without satisfactory service are poor. So low-cost systems, which can be operated and maintained by community participation, remain priorities for the remainder of the Decade and beyond. Consideration of the developing world's needs alsó highlights the use of water for agriculture and power. Drought still threatens millions of people, especially in Africa, but in many places famine may be averted by appropriate irrigation. At the other extreme where water is abundant, the use of turbines is potentially an important power resource. In spite of a lowering of oil prices, continuing and often worsening shortage of foreign exchange afflicts most of the poorer countries and calls for maximum utilization of local renewable sources of energy. In many parts of the developing world increasing industrialization is accelerating the deterioration of water quality. Both surface waters and groundwater are affected. In contrast to the low-cost and simple systems required for much Decade activity, the appropriate technology for treatment of industrial wastewater and polluted river water is often sophisticated and complex. Developing World Water - 2 deals with all these aspects of water for the developing world. The rangé of topics covered is wide. Most readers of the first volume of Developing World Water liked the short well-illustrated articles, so we have used the same pattern again, and have tried to provide material which is useful and interesting for the speciálist and non-specialist alike. Fifteen thousand copies of Developing World Water reach technical and administrative decision-makers throughout the world. WEDC and the publishers believe that Developing World Water is making a signicant contribution to the Decade and to providing useful information that helps the decisionmaking process. WEDC has been involved in water and waste engineering for developing countries for more than 15 years and is an appropriate centre for co-ordinating the preparation of these books. We are most grateful to all authors for their contributions and to others who have provided colourful pictures and who have assisted in other ways. JOHN PICKFORD Editor-in-Chief Editorial Assistant Editorial Team Professor John Pickford Morag Murcott WEDC, Loughborough, UK Adrián Coad Richárd Faulkner Richárd Franceys Len Hutton Margaret Ince Bili Moffat Michael Smith