While the National Observatory of Agriculture (ONAGRI) welcomes a filling rate of 38.32% of the dams following recent precipitation, a discordant voice breaks the ambient optimism.
The expert in water resources and adaptation to climate change, Raoudha Guefrache, alert on too simplistic – even misleading – of figures.
“What we store is only a tiny part of what falls from the sky. The rest … evaporates, “she says.
According to her, between 50 and 60% of precipitation evaporate even before reaching the tanks, due to global warming and the greenhouse effect. Result: only 10% of recent rains have really benefited the filling of the dams.
“Beneficial” rains … but without real effect
Guefrache recalls that if the center -east regions have experienced a spectacular increase in precipitation -reaching 159% of the usual averages -this is not translated into a concrete improvement in the water situation.
“As long as these rains do not reach the dams or irrigate the lands, it is deceptive to speak of beneficial rains,” she deplores.
In March, precipitation represented only 23% of normal averages. In February, the situation was barely better, with 35% of the volumes usually recorded in the dams.
Free fall storage efficiency
The observation is severe: the actual ability of dams to remember water decreases day by day. While they could formerly absorb rain flows of almost 300 cubic meters, they only capture only 20 to 30%.
In question: siltation, online losses, infiltration and ineffective of the overall collection system. Added to this is the continuous increase in temperatures and the growing irregularity of precipitation, two direct consequences of climate change.
Guefrache calls for a radical change of paradigm: “It is urgent to stop taking the raw figures for truths. The falling water does not remain. Between evaporation, absorption by soil and infiltration, what we really store is much less. »»
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According to the latest data published by the National Observatory for Agriculture (ONAGRI), the overall filling rate reached 38.32% in April 28, 2025, against 36.5% on April 16. The total volume of resources stored in the dams now amounts to 907.47 million cubic meters, compared to 865.3 million two weeks earlier.
