Venice is facing the highest tide in 50 years and the MOSE flood barriers system on Tuesday saved the city from flooding again as a 173 cm (68 inches) acqua alta moved into the lagoon. Without MOSE, local officials said, some 82% of Venice would have been under water.
The acqua alta was the third highest ever after 193 cm (76 in.) on November 4, 1966 and 187 cm (74 in.) on November 12, 2019. Without those barriers Venice would be submerged in a catastrophic way, and despite the many nay-sayers MOSE faced over the years, those barriers are saving a heritage of humanity,” said Transport and Infrastructure Minister Matteo Salvini.
He said Tuesday’s acqua alta was “worse than the great tide of three years ago”. This mammoth acqua alta offered the first real stress test, officials said, for MOSE’s 78 mobile barriers, two and a half years after they were first used in July 2020, after years of scandals and infighting over the usefulness of the work. Italy is currently experiencing a nationwide rainstorm, and autumn marks the beginning of the ‘high water’ season, when canals routinely overflow, flooding streets and squares. The causes are both natural and man-made.
Decades of pumping groundwater caused significant damage to the delicate foundation before the practice was halted. Weather experts say the high-water threat has been increasing in recent years as heavier rains have hit northern Italy. Other possible explanations for the phenomenon include the sea floor rising as a result of incoming silt and gas extraction in the sea off Venice undermining the islands. According to a recent study, plate tectonics are also to blame as the Adriatic plate is sliding beneath the Apennine Mountains, causing the area to drop in elevation. Scientists have conceived various ways of warding off the waters since a catastrophic flood in 1966 and the MOSE system of moveable flood barriers reached completion after years of controversy.
