The integration of land use in public water reservoirs plans – A critical analysis of the regulatory approaches used for the protection of banks

The water reservoirs created by dams and used for public water supply, irrigation or electricity production, have several environmental, economic and social values, and constitute strategic reserves in periods of water scarcity. Reservoirs are vulnerable to the impacts of land uses on their banks and so require careful planning and development control. Systematic studies on how water reservoirs plans formulate land use rules are, however, scarce. In Portugal, reservoirs for public water uses have been subject to protection plans but those have not raised much attention. This paper analyses the rules established by reservoir protection plans adopted in Portugal and assesses if the legal regime revised after the Water Framework Directive (WFD) entry into force has altered their regulatory approaches. The analysis uses a methodology based on a set of analytical factors proven valuable for comparative studies on regulatory approaches. The findings revealed that the Reservoir Legal Regime (RLR), as reviewed to adapt to the new regulatory framework that followed the WFD approval, did not bring robust changes to the earlier regulatory praxis. Although the relative importance of rules for reservoir banks is slightly reinforced, they are maintained as predominantly prohibitive and still poorer than before concerning targets definition. The increase of conditioned rules is not followed by a corresponding increase in mentioning indicators or nutrients. As rules on the reservoir banks are to be assimilated by different users and agencies, the paper stresses how they could foster more substantiated, referenced and balanced deterrence-compliance formulations in order to incentivize innovative land use options.