MULTICRITERION DECISION ANALYSIS FOR CONFLICT RESOLUTION IN TRANSBOUNDARY RIVER BASINS by J. GANOULIS, El. Kolokytha and Y. Mylopoulos Division of Hydraulics and Environmental Engineering, Department of Civil Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece e-mail: [email protected] ABSTRACT Sharing international waters in transboundary river basins may lead to potential conflict, political tensions and even, in some extreme cases, as the media often predicts, to armed confrontations. The reasons behind these situations may be of an internal nature, or caused by external or international forces. Internal issues include temporal fluctuations of available water resources, conflicts in water use between different sectors (drinking water, agriculture, industry), mismatch between water supply and water needs and other institutional, legal and economic factors. External or international issues include socio-economic, cultural or political differences, and historical and geopolitical issues. All these reasons may result in countries setting different objectives and having different management plans for their shared national water resources. Integrated water resources management in transboundary regions involves alternative options for water storage and use (reservoirs, river diversion and irrigation systems), for wastewater treatment and disposal (biological oxidation, nitrification-denitrification, use of pipe outfalls in different locations and use of lagoons or aquifer recharge), different states of nature (climatic conditions, type of soils, irrigated crops, irrigation systems and socio-economic environments) and various preferences or objectives (economic, social, environmental, aesthetics, etc.). Alternative options may carry environmental consequences and risks to ecosystems and human health, such as microbiological and toxic contamination or eutrophication. The impacts on the environment and their prevention should be weighted against the economic benefits and social consequences. Multicriterion Decision Analysis (MCDA) is proposed in this paper as a decision support methodology for managing transboundary risks related to different criteria and objectives set by different countries. For this purpose, three alternative methods are proposed in order to facilitate negotiations and the final decisions. All are based on the combined use of modelling and a decision support method called Composite Programming (CP). In the first method, each country proceeds separately and evaluates alternatives according to its own objectives. In the second approach the different objectives used by the two countries are first traded-off and then alternatives are ranked according to the composite objectives. The third method is based on the aggregation of the countries' different alternatives in order to obtain a consensus between the two partners. The case of the international river Nestos/Mesta, flowing between Greece and Bulgaria, provides an illustration of this methodology in practice. KEYWORDS: Transboundary Water Management, Multicriterion Decision Analysis, The Nestos/Mesta River 2 INTRODUCTION On a global scale, the importance of transboundary water resources is far from negligible: according to reports submitted to the UN, about 50% of the land on Earth (excluding Antarctica) is located in internationally shared water catchments. About 40% of the world's population lives in this area, which extends over more than 200 international river basins. Historically, rivers and lakes have been used to determine frontiers between countries and because of this have been the scene of numerous conflicts throughout history (e.g. the Rhine between France and Germany, the Rio Grande between the USA and Mexico, the Odder and Neisse between Germany and Poland, and the Amur and Ussuri between Russia and China). In many cases river basin boundaries do not match national political borders. Issues and problems of transboundary water management emerge, especially when countries occupy parts of the upstream or downstream area of the river catchment. Water resource sharing then increases in complexity (e.g. the Nile between Egypt and Sudan, the Middle East conflict over the Jordan River, the Danube between many European countries, and the Elbe between the Czech Republic and Germany). A basic question is how and through what kind of processes water in transborder regions may unify rather than divide sharing nations, and how stakeholders in international water catchments may increase their benefits without causing losses to others. The issue is complex because political issues of domestic and external policy are involved and affect all considerations from technical to ecological This paper first reviews the complexity of transboundary water resources management and different strategies for regional negotiations. Then, the technical and institutional approaches, which may lead to agreements on sharing waters, are analysed. Effective implementation of such treaties may be realized following a bottom-up approach, based on “regional partnerships”. There is a need for such regional exchanges and partnerships to be coordinated, and this makes the creation of the UNESCO Chair/INWEB (International Network of Water – Environment Centres for the Balkans) extremely important. TYPOLOGY OF TRANSBOUNDARY RIVER BASINS AND POTENTIAL CONFLICTS Types of Transboundary River Basins Different types of borders dividing states that have some territory in a river basin are shown in Figure 1: (1) Borders cross the river at a point and divide the river catchment in two parts, the upstream and the downstream. In this case, there is no joint sharing of one river section by the two states. This is the case of the border between Hungary and Yugoslavia at points crossed by the Danube and Tisza Rivers or the border between Greece and FYR of Macedonia (Former Yugoslav Republic of Macedonia) crossed by the Vardar /Axios) River near the city of Gevgelia (Figure1,a). (2) Rivers serve as borders between states, like the lower course of the Danube River, which serves as the border between Bulgaria and Rumania (Figure 1,b); and (3) Borders that follow and also cross international rivers. 3 (3) (2) (1) RIVER A RIVER A R i v e r Del ta R i v e r Del ta LAND LAND SEA SEA (a) (b) Figure 1 Schematic presentation of two types of interstate borders crossing or following a river. How the interstate borders follow or cross, or both, the international rivers and how they divide rivers and river basins, will determine what type of water resources problems are or will likely be posed for bilateral or multilateral interstate solutions. A large number of international agreements for solving various types of interstate water resources problems are available for reference and act as precedents. Different water interdependencies from the South Balkans can be used as an illustrative example, (Figure 2). In the case of the Evros/Maritza River (between Bulgaria, Greece and Turkey) there are no major water supply problems as there are no other water uses besides irrigation. However, there are complex issues of cooperation in order to protect riparian areas from floods and inundations, such as occurred recently during February and May 1998. Ecological considerations of the Evros River delta have also become very important in recent years. In the case of the Aoos River (between Greece and Albania) there have been protests from Albania regarding the construction of a large dam on the Greek side. In the case of the Axios/Vardar River (between Greece and FYR of Macedonia) the number of conflicts on water resources management issues has increased since 1965, due to intensive irrigation, plans for constructing new dams in FYR of Macedonia, and the accelerating pollution of the river. The greatest challenge in the region is the Nestos/Mesta River between Greece and Bulgaria. Despite earlier agreements, Bulgaria has in the past withheld water for increased agricultural and industrial needs. Since 1975 the Nestos flow has declined from 1500 million m3 to 600 million m3 resulting in repeated Greek protests. A series of negotiations did not resulted in agreement; and failure to resolve the situation resulted in conflicts between the two countries. Recently an agreement has been reached, but noticeable pollution from the Bulgarian part has raised the level of tension in a region of Greece highly dependent on irrigated agriculture and hydropower. There is a major need for cooperation and application of European Union (EU) guidelines for Integrated Water Resources Management (IWRM) in these transboundary river basins. 4 Figure 2: International river basins in South Balkans. Potential Conflicts of Riparian States in Water Resources Development Disputes over shared water resources among nations have a long history. According to Gleick (1991, 1992), four classes of water-related disputes may be distinguished, i.e. water resources as 1) strategic goals 2) targets during war 3) tools or weapons of conflict, and 4) roots of conflict. Conflict situations in transboundary water resources management occur on at least two levels: 1) conflict among goals, objectives and attributes, in particular economic, environmental and social criteria and 2) conflicts of interest between countries and among groups of actors involved. Goals: Broadly speaking, every state has social, economic and political goals linked to water resources development, conservation, and control and protection of the river basin. Economic goals