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If we do not change the formulas and invest in improving the performance of purifiers, starting next year agriculture will have to halve the amount of water it can withdraw from rivers. And if 2025 turns out to be a year of drought like 2022, then it would be a big problem for Made in Italy agri-food production. The Piedmontese section of the Anbi, the association that brings together water basin management consortia, raised the alarm, but the concern concerns all of Italy.
At the center of the issue is the application of the European legislation on the so-called ecological runoff, scheduled for 2025. In practice, to continue with the river depollution process, the basin authorities will have to determine the maximum volume of water to be withdrawn from the rivers so that, thanks to greater dilution, the quality of the water itself is better. All of this, unlike what happens today, without exceptions. Not even in the case of particularly hot and dry summers due to lack of rain.
Among the first to raise the problem was Mario Fossati, who leads the Est Sesia consortium and is also director of Anbi Piemonte: «The water from the rivers – he explains – is used by industry, agriculture and aqueducts, but It doesn’t say anywhere how much should remain in the river. Now, however, by virtue of the framework directive, a certain quantity will have to remain.” The reason is simple: the more water remains in the riverbed, the more any pollutants are diluted and the river re-oxygenates better. The point is how this minimum quantity is decided: «At the moment – continues Fossati – the formulas have been established by observing the historical series of river flows, and on this statistical basis the minimum percentage on the average quota has been set». But this means that, in drought years like 2022, if the regulation had already been in force not even a drop could have been taken.
Already in 2019, the Piedmontese water consortia had started an experiment to analyze the waterways point by point. At the end of the tests, many different values of minimum vital flow had been defined, rather than a single statistical average: the result is that the sum of the many points gave rise to an overall value significantly lower than that determined in the traditional way. «In 2022 – recalls Fossati – we had to resort to exemptions, to withdraw more water from the rivers and save agriculture from the absence of rain. With the new ecological runoff coefficients, 90% of Italian rice production will be at risk, which is concentrated between the Vercelli area, the Novara area, the Biella area and the Lomellina area. But the rows of fruit and the uncultivated areas of naturalistic and tourist interest will also suffer.”
There is therefore less than a year left to find the solution: «One way – explains Fossati – could be to invest in improving the performance of the purifiers, so that less water is needed for the process of diluting pollutants in the rivers. The other way is not to establish formulas on the table, but to experiment site by site, section by section”. The third way, in the event of drought, is to still provide for the possibility of exceptions.