A multidisciplinary team of researchers from the humanities and social sciences, including geographers, sociologists, and economists, worked together to develop a tool for evaluating coastal zone vulnerability. The results of this collaboration are presented in this article. Clearly, the vulnerability of the coastal zone is exacerbated by the combination of increasing socioeconomic stakes and high-level natural risks that come together in this limited geographical area. Whereas natural dynamics make the shoreline intrinsically mobile, with, in most cases, a tendency to drift inland, the evolving human activity in this zone adheres to a contrary logic; it progresses toward the sea, often working to define the coastline permanently through seawalls and jetties, for example.

This highly developed coastal area is today at risk, the result of telescoping natural and anthropogenic forces. Given the risk, the notion of sustainable coastal development within the framework of integrated coastal zone management (ICZM) needs to be considered. If truth be told, the socioeconomic breaking point has apparently already been reached at several sites, where the cost of defending the coastline sometimes exceeds both the value of the property threatened and the financial means of the various local authorities, particularly the coastal communities. Certain imminent dangers have forced municipal governments to take emergency measures and the national government to resort to expropriation. Evaluating the risks of erosion and submersion thus appears to be an inevitable part of any forward-looking, strategic approach to coastal zone management.

The method presented in this paper permits coastline vulnerability to erosion and submersion to be analyzed and evaluated from several different angles: the exposure to risk, which concentrates on the hazards and the stakes; the management of risk, which seeks to minimize risk through public policies of prevention and restoration; the remembrance of risk, which works to learn from past hazardous events; and the perception of risk, which focuses on how the different actors and users perceive the diverse risks. From these four approaches to risk analysis come five factors—hazards, stakes, management, events, and perceptions. Each one is analyzed and evaluated on a separate grid, facilitating the development of vulnerability indicators from detailed lists of descriptors. Elaborated in collaboration with risk managers and local authorities (elected officials), these grids are designed to become a decision support tool within the ICZM framework.

Undertaken as part of the French National Coastal Environment Program, this research seeks to promote coastal risk management within a more integrated coastal zone management approach.