The city was preparing for a high water level of 145 centimeters, Mayor Luigi Brugnaro said on Twitter. Saint Mark’s Square is already under water. He said the city’s flood defense system, MOSE (system of protection by mobile artificial dikes), was not operational. The system was first triggered this year, when it protected the city from flooding in October.
The project called MOSE (Moïse in Italian, Electromagnetic Experimental Module) is a complex engineering system allowing “waterproofing” of the Serenissima thanks to 78 dikes placed at the entry points of the lagoon. It is a network of caissons filled with water, supposed to be able to rise in 30 minutes, to create a barrier capable of withstanding a rise in water three meters above normal.
The causes of MOSE not working on Tuesday are not known. The mayor had just congratulated himself on Sunday on the demonstrated effectiveness of MOSE in the face of heavy rains. He had pointed out that he had remembered two tides since Sunday.
The dreaded high water level for the city means Venice faces a red alert level. Weather forecasts predict water levels could reach 135 centimeters on Thursday and Friday.
Luca Zaia, the president of the Venice region, said the damage could amount to 500 million euros.