France is changing its climate. If this period of drought is unprecedented, it mainly confirms a series of high temperatures in summer. “France has entered a stage where our climate has become semi-arid, a bit like Spain,” judges Franck Galland, president of ES2, an engineering consultancy in urban resilience at BFM Business.
If France believed itself protected from climatic risks, this heat wave, after winters marked by disastrous episodes such as the torrential rains inside Nice in 2020, forces the country to adapt to manage its water.
And precisely, Spain is a good example in this regard. “We have a lot to learn from the way they were able to adapt to a climatic restriction with regular and increasingly long droughts, but also to particularly intense rain events in which for two or three days you have the equivalent of a year’s worth of rain. Franck Galland continues.
invest massively
According to him, one of the first measures is to limit leaks, currently around 20%. To do this, “we must invest massively: 2,000 million a year for the renewal of pipes”, he warns because the French network represents 900,000 kilometers of pipes. Not only is the replacement expensive (320 euros per meter) but it causes regular work and therefore disputed in the cities.
The other major axis is the recycling of used water. France only reuses less than 1% of its “grey water” that could be used for agriculture. For comparison, Israel recycles almost 90% of its water.
But this implies a change in regulations in France to facilitate treatment, which will necessarily have a price. Recycling water for agriculture can cost 10% more per cubic meter.
artificial recharge
Another solution is desalination plants. None exist in France, while Barcelona has the largest in Europe, built after a terrible heat wave in 2008.
Finally, the issue of groundwater, which is struggling to be filled, must also be on the table, Franck Galland believes. “We have to open our minds: the artificial recharge of groundwater is strongly practiced in the Middle East, we have to be able to take advantage of the very heavy rains in winter to be able to re-inject our groundwater,” he explains.
In this case, the great storms that fall on very dry land do not allow groundwater to be recharged. The issue of artificial recharge, by capturing watercourses in winter, was already raised by ANSES, which considered it “conceivable under conditions”, in a 2016 report. But pollution, particularly with fertilizers or pesticides, is one of the main obstacles to overcome.
Source: BFM TV
