Drought: Legambiente, 22 billion cubic meters of water recoverable

The potential that the collection of rainwater in cities and the reuse of waste water for agriculture would have together

, i.e. about 3 times the capacity contained in the 374 large reservoirs in operation, which amounts to about 6.9 billion cubic meters.

This is the estimate made by the CittàClima Observatory of Legambiente, which in the dossier "Accelerating change: the challenge of water passes through the cities" gives a snapshot of the situation even in the face of the fact that "cases of damage due to of drought, from 6 in 2021 to 28 in 2022".

The NGO is asking for a roadmap.

"Important numbers" says the environmental association which presents the dossier in view of World Water Day, March 22, and

, which has objective is not only accumulation to deal with periods of shortage, but above all the reduction of water demand and therefore of withdrawals and uses in all its sectors".

Cities must become "laboratories" and have a "decalogue" with a series of actions and tools "that can be replicated and that could be implemented quickly and with costs, in some cases, entirely sustainable": from approving in all Municipalities 'Building regulations' with obligations to recover, reuse and save water to make the purification of urban waste water more efficient, to increase the permeability of the urban fabric.

The Green Swan calls for "

of our cities that aims at at least 20% recovery of rainwater by 2025, 35% by 2027 and 50% by 2030; and from the need for the transposition of EU regulation 741/2020 for the reuse of waste water - under observation at the Ministry of the Environment and Energy Security - to be done rigorously".

In 2020, the rainfall data of 109 provincial capital cities amounted to around 13 billion cubic meters (processed by Legambiente on Istat data) of rainwater that

fell on roofs, asphalt and concrete and was conveyed into the sewers or watercourses.

"An enormous waste if we think that they correspond to 40% of the average annual water withdrawals in Italy (about 33 billion cubic metres)", recalls the NGO.

Optimizing the water cycle in the city would also make it possible to increase the resources available for agriculture: with purifiers there would be 9 billion cubic meters of nutrient-rich water a year, of which in Italy only 5% is used, according to the Utilitalia data.