The heavy downpours of recent weeks are not enough to fill the water tables in some regions. Because after periods of drought, soils absorb water with difficulty.
A recharge that takes time. After the significant drought experienced this summer, and even in previous months, the water tables still show a significant deficit, despite the heavy rains that have fallen in recent weeks. The cause in particular is overly dry soils which do not absorb water sufficiently.
“The (water) level should be much higher”
In Saint-Jean-de-Fos, in Hérault, water has finally reappeared at a depth of more than 100 meters in the Clamouse cave, popular with caving enthusiasts and from which we can observe the water table supplying the surrounding area. . Good news directly linked to the heavy downpours that the region has experienced recently.
But if the water level has risen in the water table, experts remain worried. “Despite the 30mm of water that we had over a period of two and a half months, it is not enough to recharge this level (of water) which should be much higher”, assures BFMTV the technical director from the Clamouse cave Sandro Casagrande.
“I should have water at the level of my chest,” proclaims the speleologist, his feet nevertheless very dry in the cave.
Water that takes time to penetrate deep
In mid-November, too many water tables remain well below seasonal norms, particularly in the Rhône valley and around the Mediterranean.
The main reason is the lack of rain, but also sometimes the type of soil and its capacity to absorb water.
“If I ever pour a little water on a millefeuille for example, very quickly I will moisten the first slices, on the other hand if I want to moisten the very last slice, I will have to wait a long time before the water go all the way down,” explains Jean Luchier, hydrogeologist at Imageau, to BFMTV.
Between floods and insufficient level
The situation is mixed in the country. In the North and West, levels are higher than seasonal norms, but experts call for caution and point out that the situation is evolving.
“What we need is for it to continue to rain occasionally to guarantee consistently high levels and keep these levels above normal,” BRGM hydrogeologist Violaine Bault tells BFMTV.
In Pas-de-Calais, there is no shortage of rain, to the point of having caused the water tables to overflow, worsening the floods in the department. Over the last thirty days, France has experienced record rain, with 237.3mm of cumulative downpours between October 18 and November 16, according to Météo France.
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