Public perception of engineering-based coastal flooding and erosion risk mitigation options: Lessons from three European coastal settings

• We propose a qualitative framework for the analysis of coastal risk mitigation options.
• We identify and assess the determinants of coastal risk mitigation option perceptions.
• We identify the centrality of the governance context when assessing a mitigation technique.

Recent damages and losses associated with coastal floods have generated many analyses dealing with overexposure to flood risk, its consequences, associated technological choices and governance principles, and what seems to be a poor understanding of the causes and consequences of floods and working of coastal defences at the local level. While many analyses demonstrate that risks are both physically and socially constructed, in this paper we go further by analysing risk mitigation options (engineering works) as being dual (physically and socially constructed) as well.When envisioning mitigation options through stakeholders' perception, one can observe a mix of intertwined statements associated with the relevance the specific risk that is dealt with, dealing with the sometimes incomplete knowledge associated with the mitigation option and its performance at reducing risk, and, dealing with the value conflicts that may be present when envisioning a particular flood risk mitigation strategy. Our research question is “what are the drivers of stakeholder perceptions when envisioning engineering-based mitigation options.”Through qualitative empirical fieldwork conducted in three European coastal settings (Cesenatico, Santander and the Gironde Estuary) we demonstrate here that engineered mitigation solutions are socially construed by referring to individual and collective heuristics associated with these options. These heuristics may lead to poor social acceptability of envisioned mitigation options, poor acceptability not directly linked to the performance in terms of risk reduction.