A Cost‐Effectiveness Analysis of Water‐Saving Measures for the Water Framework Directive: the Case of the Guadalquivir River Basin in Southern Spain

The aim of this paper is to contribute to the still scarce literature on Cost‐Effectiveness Analysis (CEA) in the context of the EU Water Framework Directive (WFD) in water scarce areas illustrated through a case study in Southern Spain. CEA is the preferred method to select policy measures to achieve the good ecological status of water bodies as prescribed by the WFD. It generates a ranking of the measures, according to the ratio between the equivalent annual cost and the reduction of impacts, to select the measures to be included in the Program of Measures (PoM). Here, the water‐saving measures discussed in the public participation process for the elaboration of the PoM for the Guadalquivir River Basin are analysed using CEA. A methodological approach, including uncertainty for cost and efficiency of measures is proposed. A comparison between pressure and impact analysis of the effectiveness of measures shows that, in the context of the WFD, CEA should be based on the impact of the measures rather than on the pressure reduction, as the latter can lead to a misleading ranking of the water‐saving measures.