WATER SUSTAINABILITY: EVALUATION OF ALTERNATIVE WATER SUPPLY METHODS IN GREEK AND EUROPEAN ISLANDS

Water is a very valuable natural resource absolutely necessary for life. Lately water resources are facing very high pressure from continuously increasing demand. Besides, various areas face water shortage due to decrease of precipitation, irrational use, losses and other reasons. Furthermore the importance of water resources is getting more and more obvious after realising that the water availability is not any longer guaranteed as it was used to be considered until recently. Various water supply methods are applied in different cases in order to satisfy water demand, such as dams, desalination units and water transport. Each of these methods however has different environmental and social impacts. The objective of the present work is to investigate the issues and parameters that identify the water sustainability. To that effect, a detailed literature review for the already defined water sustainability indexes is carried out. Then, the various alternative water supply methods are analysed in terms of technical and economic as well as feasibility characteristics taking also into account their sustainability. A set of indicators has been suggested in the literature to assess the resource sustainability. One of the results of the present work is the comparative evaluation of these indicators. Finally, a multicriteria optimisation model is developed for the selection of the best water supply method in each different case.