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Newsletter and Technical Publications Executive Summary (suite) Chapter 5 Economic value of water has to be considered in the development of any kind of management scheme related to water resources. Restoring water quality in lakes and reservoirs and/or preventing pollution leading to eutrophication or to any other kind of water degradation, needs to be examined from an economic standpoint. This means both to understand the origin of such problems and to implement more successful programmes for restoration and prevention. The concepts of water scarcity and economic value, as well as of externalities and other aspects associated with the allocation of water among uses and users, are emphasized. Evidence is presented on the economic impacts of eutrophication through the estimation of costs and benefits of reducing eutrophication or improving water quality in general. The evidence includes different examples from the U.S.A., Europe, and developing countries. The idea of economic instruments for prevention and control of eutrophication is developed, including complementary to direct regulating schemes, covering from diverse types of charges to the development of markets of water rights and emission permits. Examples of implementation of taxes or effluent charges from selected European countries, the U.S.A., Mexico, and Brazil are described. The international experience shows that the effluent charges can be reasonably effective to improve water quality. It is suggested that the rates for the taxes or effluent charges need to be set at a sufficiently high level so they become a real incentive for abatement. Information is also provided on sound methodologies of benefit/cost analysis as a mechanism to evaluate or prioritize different initiatives of prevention and control of eutrophication, for restoration of eutrophic lakes and reservoirs and for improvement of water quality. Economic valuation of market and non-market resources, which are not treated within formal markets and/or that may have no price at all, is discussed. The contents of the chapter indicate that effective planning and management of lakes and reservoirs depends not only on a sound understanding of the physical and biological systems of these water bodies, but also of their value to people and the institutions that govern them. An understanding of economic benefits, costs, and policy instruments is vital for effective management. Chapter 6 A review of the different methods available to solve problems related to eutrophication of lakes and reservoirs is presented. Because advanced wastewater treatment techniques are expensive and difficult to operate, detailed information is mainly provided for the "soft" technological and most cost-moderate techniques. These are directly applicable to developing countries. Also discussed in detail are recently developed techniques (i.e., ecotechnology), which are particularly suitable for treating non-point pollution sources, and are relatively cost-moderate, effective, and easy to operate. Separation of different types of waste and wastewater at the source is discussed as an additional possibility to find more ecologically sound solutions to problems related to wastewater treatment. It is suggested that separation can be carried out in combination with properly selected treatment methods. Nontraditional sanitary solutions, based upon separation at the source of different types of wastewater, are a possible solution for developing countries, which do not have sewage system. Bottom sediments can become an internal source of nutrients and contribute to the eutrophication of lakes and reservoirs. Different methods are available for in situ treatment of the sediments, such as aeration, capping, and chemical treatment. Removal of sediments by dredging is another option to remediation of contaminated sediments. However, remediation of sediment, particularly sediment removal, is not a sustainable and long-term solution unless the external load of nutrients from other sources in the watershed is minimized. General suggestions cannot be made on which method should be applied to solve specific problems related to eutrophication. However, it is possible to give guidelines on how to select a good solution to specific environmental problems. The guidelines are presented with the help of several decision-making trees and references to tables included in the text to help in the selection of proper solutions to different problems. In addition, the approximate investment and running costs are mentioned for all solutions. However, the actual cost depends on local conditions. It is suggested to develop eutrophication and dissolved oxygen model of the lake or reservoir with an indication of all sources of nutrients and organic matter, which would allow the prediction of the effect of the reduction of the nutrient discharge from all sources. However, such a model requires a good data bank. Data for modeling and other management purposes can be obtained by monitoring. Principal factors that need to be considered in developing a reliable and cost-effective monitoring programme are described. The technical aspects of monitoring, which are unique to eutrophication, are discussed. Simultaneous abatement of point and non-point sources of pollution is necessary to achieve acceptable results in the management and control of eutrophication. A total, holistic lake and reservoir management, including consideration of point and non-point sources, land use control of the entire watershed, and proper solution to problems associated with solid waste, is needed to ensure an ecologically sound solution of eutrophication, which can be realized with limited economic resources. Chapter 7 The environment of lakes and reservoirs changes along with the economic activities in the watershed. Therefore the structure of the management of the lakes and reservoirs needs to be adaptable and able to respond to the continuously changing environment. In addition, the development of adaptive management for each reservoir or a cascade of reservoirs is extremely important because each reservoir has unique properties and environment. Selected examples are used to discuss the state of lake and reservoir management with respect to eutrophication in different parts of the world. The examples include lakes and reservoirs in Russia, Africa, and North and Latin America. An original method to enhance the self-purification capacity of valley reservoirs developed in Russia is described in detail. Problems accounted in the management of the Baltic Sea are also included as an example of multilateral management practices. Various management arrangements at local, national, and international levels are examined using the above examples. The different formats and development stages of institutional and legal instruments of lake and reservoir management are illustrated and issues, which need international resolution, are pointed out. The examination of the examples indicates that the technical "know-how" alone is unlikely to succeed in sustainable water quality management without sound institutional support and good governance. It is further shown that water resources shared at the international level need clear conventions in which the responsibilities and privileges of the participating states are clear, and where clear protocols for management cooperation and dispute resolution are transparent. The management of reservoirs, as indicated by the example from Latin America, is a complex operation that needs permanent input from basic sciences. The introduction of management plans prior to the reservoir construction and operation is an economic and social issue of relevance. It is fundamental to establish a monitoring programme that will follow the changes from the commencement of the impoundment. It is expected that predicted climatic changes will affect the hydrology of lakes and reservoirs. In the tropics, a decrease in precipitation and a possible increase in evaporation are indicated to be up to 40% for 1 to 2o C increase. These changes will have a significant impact on the lakes and reservoir ecosystems, particularly on the eutrophication, as well as economic impacts on fisheries and the potable water supply. Management plans should consider these changes. Chapter 8 Most important issues, which need to be considered in a new approach to planning and management of eutrophication of lakes and reservoirs, are highlighted and discussed in this chapter. Eutrophication of lakes and reservoirs is an acute problem and will remain in the future, due to the continuous input of anthropogenic wastes to the surface waters. In many countries eutrophication of water bodies has reached dangerous levels often accompanied by severe consequences. The effects on human health due to the lack of sanitation and the chronic effects of toxic algal blooms are two of the many indirect effects resulting from eutrophication. The loss of jobs resulting from heavy fish kills due to the excess of biological oxygen demand (BOD) or toxicity is another example of the indirect effects of eutrophication. Successful solving of eutrophication problems requires to consider the overall situation, the opportunities to integrate the complex biogeophysical, social, and economic problems, and to emphasize the multidisciplinary approach. The watershed approach to the management of the lakes and reservoirs is emphasized. The need for training programmes to build up expertise on water issues among government staff, managers, water users and general public is discussed. It is suggested that an ecosystem approach should be the aim of a sound training objective. Economic problems related to water issues will become more important in areas with large populations. Therefore the economic aspects have to be considered in an integrated approach to eutrophication. The economic opportunities associated with the control and prevention of eutrophication should be evaluated. The prevention, control, and management of eutrophication can provide new job opportunities and tools for economic development. The requirements to reduce pollution and eutrophication, to conserve water and avoid its degradation, carry significant economic and social costs. Priorities towards maintaining sustainability will have to face cost-benefit and cost-effectiveness evaluation. A certain level of eutrophication can provide conditions for exploitation of biomass or irrigation with fertile water. This should be included in the new approach to the management of eutrophication. Financing of eutrophication can be provided by different agencies. However, it is very important to have a local source of finances as a counterpart for international or national loans. It is necessary to prepare a list of techniques and ecotechnological solutions that can be applied for control and remediation of eutrophication at low cost. Each aquatic ecosystem is unique. Therefore it is necessary to approach the problem of eutrophication with a long-term perspective, integrating regulations, institutional organizations, public participation and participation and support of the decision-makers. The emphasis should change from recovery to only prevention, control and conservation of the lake or reservoir. The management should be integrated, predictive, and oriented towards an ecosystem approach. A continuity of long-term planning should be secured by its development at the watershed level with public participation. In addition, the integrated management should be adaptive, constantly producing new mechanisms, ideas, and tools, with the perspective that the eutrophication of lakes and reservoirs will remain in the future. This can only be achieved by proper education of the managers, decision-makers, and the general public, and activities at the local level with political and managerial support.
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