Index-Based Cost-Effectiveness Analysis vs. Least-Cost River Basin Optimization Model: Comparison in the Selection of a Programme of Measures at the River Basin Scale

Increasing water scarcity challenges conventional approaches to managing water resources. More holistic tools and methods are required to support the integrated planning and management of fresh water resources at the river basin level. This paper compares an index-based cost-effectiveness analysis (IBCEA) with a least-cost river basin optimization model (LCRBOM). Both methods are applied to a real case study to design a cost-effective portfolio of water demand and supply management measures that ensures compliance with water supply and environmental targets. The IBCEA is a common approach to select programmes of measures in the implementation of the EU Water Framework Directive. We describe its limitations in finding a least-cost solution at the river basin level and highlight the benefits from implementing a LCRBOM. Both methods are compared in a real case study, the Orb river basin, in the south of France. The performances of the programmes of measures selected by the two methods are compared for the same annual equivalent cost. By ignoring the spatial and temporal variability of water availability and water demands in the river basin and the interconnection among its elements, the aggregated approach used in the standard IBCEA can miss more cost-effective solutions at the river basin scale.This paper is based on work conducted as part of several projects over more than 6 years. It benefited from the financial and technical support of the Agence de l'Eau Rhone Mediteranee et Corse; Conseil General de l'Herault; Conseil Regional du Languedoc Roussillon et ONEMA. Funding was partly provided by the IMPADAPT project /CGL2013-48424-C2-1-R) from the Spanish ministry MINECO (Ministerio de Economia y Competitividad) and European FEDER funds. Corentin Girard is supported by a grant from the University Lecturer Training Programme (FPU12/03803) of the Ministry of Education, Culture and Sports of Spain. We are very grateful to Y. Caballero (BRGM), S. Chazot (BRLi), E. Vier and F. Aigoui (GINGERGROUP) and L. Rippert and his team from the SMVOL for their help during the project and for the data provided. We thank as well the two anonymous reviewers, the Associated Editor and Editor-in-Chief of Water Resources Management, for their useful and encouraging comments during the review process.Girard-Martin, CDP.; Rinaudo, J.; Pulido-Velazquez, M. (2015). Index-Based Cost-Effectiveness Analysis vs. Least-Cost River Basin Optimization Model: Comparison in the Selection of a Programme of Measures at the River Basin Scale. 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River basin management is faced with complex problems that are characterized by uncertainty and change. In transboundary river basins, historical, legal, and cultural differences add to the complexity. The literature on adaptive management gives several suggestions for handling this complexity. It recognizes the importance of management regimes as enabling or limiting adaptive management, but there is no comprehensive overview of regime features that support adaptive management. This paper presents such an overview, focused on transboundary river basin management. It inventories the features that have been claimed to be central to effective transboundary river basin management and refines them using adaptive management literature. It then collates these features into a framework describing actor networks, policy processes, information management, and legal and financial aspects. Subsequently, this framework is applied to the Orange and Rhine basins. The paper concludes that the framework provides a consistent and comprehensive perspective on transboundary river basin management regimes, and can be used for assessing their capacity to support adaptive management.Civil Engineering and Geoscience

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The Water Framework Directive (2000/60/EC; WFD) is one of the most important environmental directives of the EU. It holds the promise of cleaner European waters and better aquatic ecology. Yet, the novelty of the specific requirements of the WFD, combined with the very tight deadlines, has turned the first implementation cycle into an ―experimenting and learning‖ experience. We assumed that effective institutional settings would shape the circumstances in which measures would actually be implemented.The key to the implementation of the WFD proved to be not so much the existence of basin-level organisations, but an awareness of the necessity of a river basin approach as well as a correspondence between institutions in charge of planning measures and those in charge of implementing them. 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Or nous nous sommes rendu compte que la mise en ½uvre de la DCE ne dépendait pas tant de l'existence d'organisations de bassin, mais plutôt de la conviction partagée de l'importance de l'approche par bassin et de la correspondance entre institutions associées à la planification des mesures et institutions chargées de les mettre en ½uvre. Au sein du projet i-Five, trois approches innovantes pouvant aider la mise en ½uvre de la DCE ont été identifiées et évaluées : Les Coopérations de zones en Basse-Saxe, dans lesquelles les autorités et les parties prenantes de différents secteurs travaillent ensemble en faisant le lien entre le local et le niveau du Land. Les animateurs de bassin versant en France qui sont des médiateurs entre monde de l'eau et collectivités locales, assurant le lien entre secteurs et permettant l'appropriation de la DCE au niveau local. 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