Meanwhile, Venice remains vulnerable, as demonstrated by the tides that flooded the city last week, flooding the market, churches and hotels, depositing layers of salt that eat marble.
The 6 billion euro flood barrier has been under construction since 2003 and originally took eight years. Now, the best guess is that it will be ready by 2021 or 2022. Some experts say that given the rate of sea level rise, it may only become old decades after it starts working. Others wonder, given their sad story about whether the system will ever be ready. Parts of the underwater project are already eating away.
"I'm afraid it will never work, but I have to hope it will," said Marco Gasparinetti, a Venetian civic activist. "The alternative is to sell my home."
There are many explanations for the periodic and sometimes catastrophic floods of Venice: the inherent instability of a city built on 1
18 islands; the rising seas and the changing weather associated with climate change; the replaced tectonic plates thought to cause subsidence of the earth; dredging to create a path for tankers and cruise ships.
However, many Venetians blame the insufficient efforts to save their city.
Venice Mayor Luigi Bruniaro said that if the planned barrier were in place, damage from the last week could have been avoided.
The project is known as MOSE, an Italian acronym for an experimental electromechanical module and a reference to the biblical Moses parted at sea.
Consists of more than 70 massive, ie yellow underwater gates located across the three entrances that separate the Adriatic Sea and the Venice Lagoon. The gates are designed to rise during unusually high tides from the lagoon.
This is at least the theory. The project has been restored by consistent delays, cost overruns and political corruption.
Investigators determined in 2014 that project managers transfer taxpayers' money away from MOSE and use it to bribe politicians. Thirty-five people were arrested, including then-mayor Giorgio Orsoni and former governor of the Giancarlo Galan region.
"Delays are entirely Italian shame and we urgently need a solution," said Alessandro Morelli, head of the parliamentary committee on transport.
Engineering experts are more concerned that the project, even after it appears online, will not function as the savior as it was designed.
The first prototype of the MOSE in the 1980s, what constitutes the Jurassic era in the world of climate science, and the project is based on dramatically outdated estimates of how fast the seas can rise, according to a UNESCO report. Now, experts are talking about MOSE as a stop, something Venice can buy in a few decades while Italy comes up with a different plan.
"The MOSE decision is outdated and philosophically wrong, conceptually wrong," says Luigi D'Alpaos, professor of emeritus in hydraulics at the University of Padova, who wrote a book on Venice. "MOSE can run smoothly and seamlessly for 10 to 20 years. But then problems will arise and other actions will need to be taken. "
The intention behind the retractable gates is that when they were not needed, they would allow Venice to retain its aesthetic feel and allow fishermen and other boats to do so inside and outside the port. More importantly, the Venice Lagoon uses the Adriatic as a flush valve and its ecosystem would be endangered if sealed off the high seas
But based on forecasts for sea level rise, in the not too distant future floods should they lift so often that they function as an almost permanent wall.
Alpaos said that with sea level only 50 centimeters higher, MOSE would have to be used almost every day. In this scenario, the barrier can be used to keep Venice dry. But it would also create a far less desirable city, turning the lagoon around Venice into a stagnant algae and waste pool.
The latest report by the Intergovernmental Panel on Climate Change states that sea levels will rise between 60 cm and 110 cm by 2,100 or 2 to 3 ½ feet if gas emissions continue to increase.
The consortium that runs the MOSE project says that the barrier is designed to cope with sea level rising to 60 cm.
Floods in Venice are associated with high tides, and in recent days the city has been pouring water once and sometimes twice a day. The repeated flooding and the projections that it would worsen caused some residents to despair about the future of the city. During the first two decades of the 20th century, Venice saw high tides over 110 cm five times. For two decades in the 21st century, Venice has seen similar tides more than 130 times.
Pierpaolo Campostrini, director of a group that manages lagoon research in Venice, said that even if MOSE has been operating for 20 or 30 years, it will be worth it, given the damage that Venice is facing whenever it floods.
"We have to keep in mind that these kinds of devastating events are not only material, but affect the city's ability to continue to exist instead of being just a museum," Campostrini said.
Campostrini said it would be easier to come up with a long-term solution if Venice had any certainty that it would not be flooded so regularly. He mentioned a proposal by a hydrologist from the University of Padua, which involves injecting seawater deep underground, surrounding Venice, in an attempt to raise the city's terrain. It was just one big idea under discussion, something that could be learned "when our feet are dry," he said.
"Of course, in order to do this, you need serious research," Campostrini said. "But its price will be less than that of MOSE."