Decision-Support Tools for Beach Management in Context of Climate Change

Abstract In order to adapt to climate change, local authorities are encouraged to develop management strategy for their coastline. Thus, the Toulon Provence Méditerranée Metropolitan authority has joined forces with Cerema to initially carry out a hydro-sedimentary diagnostic and an assessment of current beach management. Then a beach classification methodology was developed based on various criteria. For urban beaches, multi-criteria analysis is a decision-making tool aimed at prioritizing action in terms of solutions to be implemented, by rationalizing investment levels for the public body, according to an intervention schedule (short-term/medium-term/long-term). The criteria involve the evolution of the coastline of the beaches and the future permanent submersion of nearby stacks, economic attractiveness and environmental value. Depending on the value of the synthetic index calculated, families of beach management solutions emerge, ranging from nature-based solutions for low-index beaches to reinforcement solutions for high-index beaches in the short term. In the medium and long term, the relocation of stakes exposed to retreating coastlines and rising sea levels is essential to increase beach resilience.