Not enough rain in Toulouse since the start of the year to make up for the water deficit
Since the beginning of November, the rain has returned to Occitania, he fell in the Toulouse conurbation 75 millimeters d’eau told us the invitation from France Bleu Occitanie, Antoine Cousin, hydrologist and hydrogeologist at AC d’eau in Toulouse. “It’s not exceptional for a month of November, but it feels good, especially since it usually falls 600 millimeters of rain a year, we’ve only got 370 millimeters since the start of the year is almost half as much.”
At the beginning of the year 2022, it has much more, the flood of January 10, 2022 had made it possible to fill the water tables of the region, but since last March, the water deficit has widened, with a dry summer and scorching, a warm autumn. “The aquifers need to be recharged, so regular rains are needed, not too intense to avoid runoff“explains Antoine Cousin, who adds “that the rivers recharge then drain the aquifers“.
The dams are dry
The 6 main dams built in recent decades, on all large rivers, including the Garonne, have lost their water level. “We destocked this summer 57 million cubic meters of water from these 6 main large dams. The four dams in Ariège are at very low levels. That of Lac d’Oô too. ” It is the snow of the Pyrenees which melts in the spring which makes it possible to recharge the dams, to feed the Garonne river. Water is also used to produce hydroelectricity, essential in this time of energy crisis. “It would have to rain a lot more over the next few weeks and until next spring to catch up with the situation.”
Precipitation patterns will change in recent years with alternating periods of drought followed by periods of rain, sometimes with torrential rains, floods and even floods. The fact that it rains also makes it possible to avoid fires in the summer, like those which we know this year in Aveyron or Gironde.