Up to 2.5 meters of water in places. At the beginning of February 2021, the municipality of La Réole (South Gironde) experienced significant flooding. In question: the exceptional flood of the Garonne, caused by the storm Justine.
– Audrey Dumain
Yes no deaths were to be deplored, the situation was not sufficiently anticipated. Forecasts from the Vigicrue monitoring system did not measure the extent of the flood. “We knew how to manage, but we were often confused by Vigicrue’s forecasts, often below the level observed”, regrets the mayor of La Réole, Bruno Marty.
The forecast announced a maximum water height of 9 meters 30, enough for the dikes to contain the Garonne. But this height has been exceeded, causing the flooding of more than 400 homes. “The fact of having alerted allowed Vigicrue to send a person on the spot who could see that the Garonne was going to rise again, so the emergency services were able to evacuate very quickly the people who had remained in their accommodation”, explains Bruno Marty.
Reinforcement of dikes
Faced with this exceptional event, lessons have been learned. Impossible to increase the height of the dikes, which would have consequences upstream or downstream. In contrast, these dikes will be the subject of reinforcement work in 2022. “More than a million euros of work is planned by the community of municipalities to strengthen them, so that during a ten-year flood, the Garonne can remain in its major bed”, details Bruno Marty.
More effective warning system
For the mayor, the big building site is mainly at the level of the resident alert system. An application has been developed, allowing the sending of SMS to citizens. The app will be able to indicate precisely who has read the message or not. And concerning the new inhabitants of La Réole, their contact details will be automatically integrated into the application when they contract a gas, water or electricity contract, “so that no one is surprised anymore”.