Isère, a department vulnerable to flooding.
In 1859, a strong flood, with a return period estimated at 200 years, ravaged the entire plain located upstream of Grenoble over more than 80 km. This flood gave rise to a protection policy based on the damming of the Isère, started 150 years ago, and lasting until the 1970s. However, the course of past floods has shown a significant risk of failure of the dams in case of flooding of the Isère river.
Faced with this risk, the Symbhi has initiated a vast development program. Based on a modern approach to flood management, it reconciles protection of agricultural land (against a thirty-year flood), protection of inhabited areas and economic zones (against a two-hundred-year flood), enhancement of natural environments and landscapes, and consideration of leisure activities and uses related to the river.