An extreme weather event cwith rainfall between 100 and 150 ml for three to four consecutive hours - in the context of a vast unstable front that hit the entire central Mediterranean area - caused the Salso river to overflow in the Licata (AG) area on 19 October 2024.
The areas bordering the river bed are historically cultivated with open-fields and greenhouses. From an initial assessment made on October 21st, the area affected by the flood covers at least 2 square kilometres. The artichoke crops in open fields, courgettes and peppers in tunnels and under glass are now submerged in mud.
A few days after the incident, companies have a clear idea of what needs to be done after this umpteenth adverse event.
"First of all," says Giovanni Chianta, a producer in the area, "we need an embankment on either side of the river that, just like the spillway created to protect the city, can act as a barrier for the entire cultivation area. Then the dams must be restored as quickly as possible, as over half of them are buried for more than half of their capacity."
Unfortunately, the significant rainfall accumulations upstream of the Licata Plain have poured into the Salso river in quantities greater than those manageable by the current hydraulic system, reaching a hydrometric height of 8.5 metres, right at the spillway. "This defence work is necessary to prevent damage to towns, property and people, in an area that is so complex and vulnerable from the point of view of hydraulic control, that it is the subject of many sector studies. Inevitably, excess water is diverted to areas where it causes less damage, as it is not possible to build expansion tanks. The farms located close to the river bed are and will be the most affected, as things stand," says Luigi Pasotti from the Sicilian Agrometeorological Information Service.
Chianta also stresses that, "considering that the full production of courgettes and peppers had just started, we can make a brief calculation of the damage that some greenhouse growers will face. A greenhouse costs 11,000 euro per 1,000 square metres, with the annual planting costs of the campaign for the same surface area amounting to 7,000 euro. Then we must add the loss of profit which, in the case of courgettes (but peppers currently have similar prices), is currently 2 euro per kg. In a 1,000 square metre greenhouse, 12 tonnes can be harvested in one year. So 12,000 kg multiplied by 2 euros makes 24,000 euros of potentially lost profit."
It is clear that these calculations are an example, because prices go up and down. In any case, the sum adds up to a total loss of 42,000 euro/hectare: an enormity from which a farm of a few hectares that has been totally destroyed will probably never recover (without even mentioning the cost of labour).
When asked about what needs to be done to prevent similar episodes from happening again, Pasotti replies that "it is not easy to give an answer for an area that is inherently very vulnerable. The floods that have occurred over time have been characterised by different dynamics, depending on the portions of the basin that have caused them. What happens downstream sometimes depends on the hydraulic structure of the upper part of the basin with its reservoirs and infrastructure, which should also have a lamination function by retaining water and reducing flooding. Sometimes, instead, the problems originate in the downstream part of the basin, where the possibility of limiting floods with infrastructural works is more limited."