The National Institute of Statistics (INSEE) has just published a study on areas exposed to the risk of flooding due to overflowing rivers in Occitanie. We learn, among other things, that more than half of the population of the Catalan country lives in sectors affected by the hazard.
In the Pyrénées-Orientales, 264,000 inhabitants out of 491,000 live in areas exposed to the risk of flooding due to overflowing rivers. This is one of the main local lessons from the recent study carried out by the National Institute of Statistics (Insee) on the subject across the Occitanie region.
The criteria on which the organization based itself in order to issue this diagnosis? “These risk zones correspond to the major bed of the watercourses, that is to say the space which the latter would occupy during periods of very high water, replies Marine Soleilhavoup, the INSEE project manager who led the study. We do not take into account here the notions of intensity and frequency. It is a maximizing zoning, especially based on the topography (reliefs, etc.). It covers very different realities: frequently impacted areas with significant water levels and others which are relatively preserved. But regardless, these areas are all potentially at risk.”
No slowdown in construction in risk areas
The INSEE study contains a lot of interesting data. Thus, if they concern 54% of the departmental population, the risk zones only extend over 18% of the territory. In short: the population is concentrated in areas exposed to hazards, the valleys through which the rivers pass and the Roussillon plain where all the waterways converge.
Furthermore, the Pyrénées-Orientales is the only department in Occitanie where the population is growing at the same rate, or even slightly faster, in risk areas (+7.2% between 2015 and 2022) than outside those areas. here (+ 6.9% over the same period). “Contrary to what is happening in the rest of the region, we are not seeing a slowdown in construction in risk areas. There could even be a slight increase”completes Marine Soleilhavoup.
83% of campsites exposed
Logically built near large population centers, many public facilities are also affected by the hazard. As for educational establishments, for example, more than half are (160 schools, 23 middle schools and 15 high schools). This is also the case for 16 of the 31 gendarmes in the Catalan country, the Perpignan police station, or even 25 fire and rescue centers out of 44.
The economic sector is not better off. According to INSEE, 83% of campsites and half of hotels in the Pyrénées-Orientales are located in risk areas. In terms of campsites, the department has the highest rate in Occitanie. The percentage of businesses potentially exposed (19,400 establishments in the non-agricultural commercial sector, or 46% of the total) is also higher than in the rest of the region (30%).
However, despite these worrying records, the Pyrénées-Orientales is not part of the leading pack in terms of the financial cost of flooding by department since 1995 in Occitanie. In the Catalan country, the bill amounts to approximately 173.6 million euros over the period. Against 1.36 billion euros for Gard. And nearly 750 million for Aude.
L’Indépendant – Infographics service
“It was floods that created the Roussillon plain”
The figures cited by INSEE do not seem to surprise Perpignan hydrogeologist Henri Got overly. However, the scientist insists on the importance of putting this data into perspective. “Roussillon is an alluvial plain, he recalls. These are the rivers which built it in the Quaternary period. The plain was born from floods. From there, anything is possible. Afterwards, we must see what the probability is that such a flood will occur based on past events. And keeping in mind that climate change has changed many things since the last big flood we experienced, the Aiguat of 1940. There is a general tendency to say that alluvial plains will all be subject to flooding. But no one can predict when. It’s like when we talk about an earthquake. We know that there are risk areas, that the hazard exists, but we don’t know when it will happen.”
Related News :