Decision Making under Deep Uncertainty: Methods and application for the drinking water sector

Traditional planning methods are ill-suited to handle developments subject to deep uncertainty. Sources of deep uncertainty can be global, such as climate change, or local, such as stakeholder preferences. Methods for Decision Making Under Deep Uncertainty (DMDU) exist and are mature enough to be implemented in the context of the Dutch drinking water sector. In this research we elaborate on uncertainty as a concept, the key ideas of DMDU, the availability of DMDU methods, and provide a demonstration of their use based on a simplified synthetics case study. The synthetic case study represents a situation where the water level in an aquifer is connected to extractions for human use. In the case study the Engineering Options Analysis method is used to evaluate how adaptation measures perform over a wide range of possible futures, which helps decision makers choose between alternative strategies. Based on lessons from this case study we also suggest that the use of DMDU methods benefits from a clear distinction between adaptation and mitigation measures.