People and Community Research

The water woes of Venice

The northeastern Italian city, built in a lagoon and growing increasingly more susceptible to sea level rise, has experienced its worst flooding in 50 years.
A city worker helps a woman who decided to cross St. Mark square on a gangway, in spite of prohibition, in Venice, Italy, Sunday, Nov. 17, 2019. Venetians are bracing for the prospect of another exceptional tide in a season that is setting new records. Officials are forecasting a 1.6 meter (5 feet, 2 inches) surge Sunday. That comes after Tuesday's 1.87 meter flood, the worst in 53 years, followed by high tide of 1.54 meters on Friday. (AP Photo/Luca Bruno)

A city worker helps a woman who decided to cross St. Mark's Square on a gangway, in Venice, Italy, Sunday, Nov. 17. Photo: Associated Press

When Jake Brannum arrived in Venice two months ago to spend a semester researching in the Archivio di Stato di Venezia (State Archives of Venice) for his dissertation, the fourth year Ph.D. candidate in the University of Miami Department of History had yet to experience the city’s high tide phenomenon known as acqua alta, or high water.

That changed last Tuesday, when a full moon exacerbated the flooding already caused by southerly sirocco winds pushing a high tide into the city of Venice, resulting in a water level recorded at 6 feet, 2 inches above sea level. The city was hit with a record third high tide Sunday, the peak of that tide reaching nearly five feet.

In the Santa Croce district on the west side of the city, where Brannum is staying, his courtyard floods with about a foot of water at high tide. Compared to the lower-lying areas of the city, he said the flooding in his area is minor.

Days before the high tide flooded into the city, Jaime Correa was leading a group of 19 students through the streets of Venice as part of their semester abroad in Italy. As they walked through the various campi (neighborhoods), they observed manholes reverberating with gargles of water from below – not uncommon for a city that is built in a lagoon in the Adriatic Sea, but proof that the underground water is as much a challenge as that imposed by high tides and sea level rise.

But last week’s acqua alta covered 85 percent of the historic city and impacted historic landmarks surrounding St. Mark’s Square, including St. Mark’s Basilica and the Doge’s Palace. The basilica’s crypt, which dates to the 12th century, was flooded by more than three feet of saltwater. Venice’s famous gondolas, one of the city’s famed tourist attractions, have been taken out of service until the water recedes. Footbridges were set up across St. Mark’s Square and throughout the city, as shops, hotels, and restaurants boarded up their doors in an attempt to prevent water from seeping into their establishments. Venetian Mayor Luigi Brugnaro declared a state of emergency, prompting Italy’s Prime Minister Giuseppe Conte to declare emergency and release funds and resources.  

Correa, an associate professor in practice and faculty in residence of the School of Architecture’s Rome Program, has visited Venice at least once a year for the past 20 years or so. “My modest perception is that the situation is rather desperate,” he said of the increased regularity of flooding. “Every year seems to be worse.” 

The highest water level ever recorded was 6 feet, 4 inches above sea level during the historic 1966 flood of Venice. Guido Ruggiero, professor of history and College of Arts and Sciences Cooper Fellow, was a graduate student already studying Venetian history at UCLA when that flooding occurred.

“Not only was everyone very concerned for the city and its inhabitants,” he said, but “as students of the city’s history we were also very worried about the truly incredible historical archives that Venice houses—over 70 kilometers of hand-written documents from before the year 1000 up through the 19th century.”

One whole series of documents that Ruggiero worked with over three months in 1970 – parchments dating back to the 1300s – was destroyed by rot by 1973. Brannum, who is conducting his dissertation research with Ruggiero as his advisor, hopes history does not repeat itself with the original copies of various 14th century court cases and arrest records that make up the basis of his research. 

“I'm fairly optimistic that the materials I work with haven't been lost to the floods,” he said. “Still, though, I feel I can't be certain of this until I actually get to hold them in my hands again.”

PROTECTING VENICE 

Ben Kirtman, a professor of atmospheric sciences at the Rosenstiel School of Marine and Atmospheric Science, said that Venice is experiencing increasing flood frequency due to two primary factors: the city is basically a cluster of islands floating on a freshwater aquifer, so as the freshwater is drawn down, the land mass sinks; and Venice is surrounded by a lagoon that is connected to the Adriatic, which is experiencing sea level rise due to a warming climate. 

The Italian government has been working toward a possible solution to prevent future flooding with the MoSE project, a proposed system of mobile barriers meant to protect Venice from high tides that has been under construction since 2003. It was originally scheduled for completion in 2011, but a series of delays pushed completion to the end of 2021. The project has already cost 6 billion euros ($6.63 billion). MoSE, an acronym for “Modulo Sperimentale Elettromeccanico,” or experimental electromechanical module, is named for Moses, the Biblical figure who parted the Red Sea, allowing the Israelites to flee from Egypt.

And while the MoSE project attempts to block or at the very least reduce the water from the Adriatic coming into the lagoon as a result of sea level rise, it does raise ecosystem concerns.

“When the flow from the Adriatic is reduced, the ecosystem in the lagoon is negatively impacted—it becomes less salty,” Kirtman explained. “As the sea level in the Adriatic continues to rise, the MoSE gates will have to be used even more frequently, leading to even further ecosystem impacts in the lagoon.” 

Spread over 118 small islands, Venice and its lagoon were designated a UNESCO World Heritage site in 1987, with the organization citing the city’s “considerable” influence on the development of architecture and monumental arts. The UNESCO World Heritage Centre continues to monitor the state of conservation of Venice and its lagoon and is planning an advisory mission to Venice in early 2020. The topographic, geographic, and material culture conditions of Venice are unique, Correa said, adding that he hopes an innovative local solution will be implemented before it is too late. 

UNESCO has given Italian authorities until 2021 to implement measures that will protect and preserve Venice’s monuments, or it will move to put the city on its endangered world heritage list.

“The absence of a place like Venice would be a shameful state of affairs for the rest of humanity,” Correa said.