In 75% of the water tables in France, the water level is lower than the monthly norms while spring has only just begun. This figure announces a difficult summer during which could come to lack.
The summer period is not yet here and fears about the lack of water are already appearing. More than fears, some speak almost of certainties like the Minister of Ecological Transition Christophe Béchu who affirmed on France 2, April 21, 2023, that in the summer “we will again have municipalities that will run out of water “. The fault is the drought and the lack of rain which for several months have prevented the recharge of groundwater. As of April 1, “75% of groundwater remains below monthly normals” according to data from the Bureau of Geological and Mining Research (BRGM). A worrying figure that leads to water shortages in several regions of France from the start of spring. “We have 40 departments in which there is vigilance or alerts” to drought which restrict access and use of water, said the minister.
The Mediterranean rim is particularly affected, as is the Rhone corridor, but regions such as part of the Grand Est or the Loire basin are also affected by these low levels of groundwater filling, according to information cross-checked from BRGM and the site Info-drought specialist.
Groundwater serves as underground reservoirs from which water is drawn to meet needs, especially in summer. The cycle of the seasons would like these sources to be recharged during autumn and winter, when the gentle and numerous precipitations infiltrate the soils until they reach the deep water tables. Problem: winter 2022/20233 was rather dry, especially between February with 32 days without a drop of rain and “a 75% rainfall deficit” according to Meteo France climatologist Simon Mittelberger, interviewed by franceinfo early March.
The recharge observed between January and December was not enough to counterbalance this dry period and if in March “the accumulation of precipitation was excessive over a large part of the territory”, its impact was very heterogeneous on the water tables. Above all, the infiltration rate was limited because the rain first “moistened the dry soils then allowed the vegetation to come out of its dormancy before succeeding in infiltrating in depth” as explained by the BRGM.
The low groundwater level is not the consequence of the winter alone, it is also due to the precipitation which was clearly insufficient during the year 2022: -25% precipitation per month over the whole year , according to weather forecasts from Météo-France. Special mention to the months of May and July 2022 where the amount of precipitation fell by 63 and 84% respectively compared to normal.
The reasons that led to the scarcity of water in groundwater are also responsible for the drying up of some rivers, rivers and surface waters. The lack of precipitation has not allowed the waterways to be fed and the problem has been aggravated by the evaporation of the resource which has been more important during the drought.
“We started from such a low and dry level, following last year’s drought, that it would have taken a winter with a clear surplus” of rain to moisten the soil and fill the water tables, explained the specialist Simon Mittelberger in March, still on franceinfo. Spring being back, we can no longer count on the rains to replenish the deep water reservoirs “except for exceptional rainfall events” according to the BRGM. After the month of March, which marks the end of winter, rainwater is mainly absorbed by the vegetation, feeds the soil and runs off more than fills the water tables.
As for the rivers, the precipitation will no longer be of any help either, or very little. But if precipitation is no longer a solution, there is still mountain snow that melts in the summer and fills the waterways. But then again, snow has been scarce during the winter and peaks like glaciers have stored less water, water that may be in short supply this summer.
Everything seems to indicate that we will have to spend the summer with much lower water stocks than last year. The year had already been marked by heavy restrictions in places. But in March 2022, 58% of the water tables showed levels below normal compared to 75% in April 2023.
Measures have already been taken in the departments and towns most exposed to drought to restrict the use of water to necessary activities only. And Christophe Béchu, Minister for the Ecological Transition, intends to continue this policy as explained on France 2 on April 21: “I will again bring together the drought anticipation committee on April 27 to take stock with the prefects and continue to watch s ‘there is no reason to tighten the orders in a certain number of places, to continue to restrict the uses of water to preserve the resource’. According to the member of the government, this situation must be an electric shock and raise awareness that we must stop “thinking that we will have water forever, all the time and for everyone”.
