The water has not finished falling in several communes of Pas-de-Calais, even if the weather conditions have improved, and the Canche, the river which crosses Montreuil-sur-Mer, remains on orange alert. Two and a half weeks after the start of the floods in the region, the public reinsurer CCR, manager of the natural disaster compensation scheme, estimated, Wednesday November 22, the cost of these floods at 550 million euros.
This amount remains limited if we compare it to recent disasters of national scale, such as the hail and drought episodes of 2022, which cost 3.5 billion and six billion euros respectively. But it reflects an event of an intensity “very abnormal” for the affected departments.
The flow of the Liane, for example, has exceeded all levels observed for fifty years. The result was sometimes considerable damage: Tuesday, November 21, the Pas-de-Calais prefecture recorded 5,849 homes affected in 262 municipalities and specified that 118 farms had already requested the support unit activated three days earlier.
The prevention devices in question
The cost of flooding, which could further increase, will be covered at least half directly by CCR, under public reinsurance. The rest will be borne by insurers, who will also have to bear most of the 1.3 billion euros in damage caused, according to a provisional estimate, by storms Ciaran and Domingos.
By their exceptional nature, the floods exceeded the capacities of some of the prevention measures, the effectiveness of which will undoubtedly have to be reinforced once the lessons of the latest events have been learned.
“Prevention works up to a certain level, but when the disaster is very large, it surpasses everything, even good measures. This is the subject of the moment: with global warming, stopping a disaster is no longer at all the same thing as it was twenty years ago. underlines Edouard Vieillefond, general director of CCR.
Systems to prevent flooding and marine submersion have represented nearly 250 million euros of investments over the last ten years in the Hauts-de-France region, including 210 million for protective infrastructure, such as dikes.
By 2050, prevention could save an amount equivalent to the current annual cost of flooding, whereas without it, climate change and the concentration of insured goods in risk areas threaten to multiply this cost by 2. 5, estimated CCR in a study published in September.