46°18'13.95'' N 1°14'48.49'' O
A vulnerable Atlantic coast
On the French Atlantic coast, low and flat shores are protected by coastal defences. Without these dykes, they would be overflown. It is the case of the Marais Poitevin. This depression has its origin in the erosion of a limestone plateau during the Ice Age. About ten thousand years ago, the sea level has started to rise slowly and the depression has transformed itself in a gulf with an archipelago. Then this gulf was filled progressively with sediments and it took a thousand years for men to make it arable by building dykes and digging canals.
After half a century of climatic remission, France has gone through destructive storms that have come to remind us how much urbanization along the coasts is vulnerable. Time has come to change our way of occupying the coast and to move urbanization further back on the continent.
A simple static simulation of a two meters rise of the sea level shows that the Marais Poitevin would be under the sea again.
This fiction proposes to give up coastal dykes and to accompany the return of the sea. The ancient archipelago will appear in the lagoon again. Urbanization will move progressively inside the continent and the lagoon will become a natural sanctuary.
Observing and making experiments
In this future lagoon, La Dive is the most western island. It was the last island of the gulf to be linked to the continent at the end of the XVIIIth century. It will also be the first to become an island again. On this island, a research center to study coastal resilience could be built. It would be a long building built on the limestone with one end towards the ocean and the other end towards the lagoon.