Six Billion Euro Project to Save Venice from Floods Tested with Success

The final part of the heavily criticized MOSE-project has finally been tested with success, and it bodes well for the Italian city of Venice, which has recently been hit by floods on a daily basis, one of which was the worst in 53 years.

By: Jesper Gundorph 12/12/2019

The famous St. Mark’s Square is one of the first places in Venice to flooded during high tides. In this photo the high tide is approximately 120 cm. above normal sea level.
(Photo: Jesper Gundorph)

The venetians can finally start to look forward to fewer floods in Venice, which occur frequently at the beginning of every winter. The last part of the €6.000.000.000-project MOSE has been tested with positive results.

The idea of keeping the high tides out from the lagoon has existed since the disastrous flood of 1966, where Venice experienced its worst ever flood, where the sea level reached 1,94 meters above normal sea level. However, it was not until 1992 the project planning was started.

The construction of MOSE (Modulo Sperimentale Elettromeccanico (Experimental Electromechanical Module)) started in 2003 and was supposed to have been finished three years ago.

Three Years Late – So far

Monica Ambrosini, architect and spokesperson for Consorzio Venezia Nuova who are responsible of the construction and maintenance of the MOSE-project, explains that MOSE will be activated whenever the high tides are expected to reach more than 110 centimeters above normal sea level, which is when parts of the city will start to get flooded.

The 2010’s are coming to an end, and it is inevitably going to be the fourth decade in a row with an increase in the number of high tides in Venice. (Source: comune.venezia.it)

When construction of MOSE was initiated in 2003, the plan was to have it ready for 2016. On December 2nd, 2019, 16 years after the beginning of the construction, the final test of the third and final group of the 78 yellow gates that the MOSE consist of were tested all at once.

In the meantime, however, the MOSE-project has been the cause of frustration and anger for a lot of the local venetians, as the project just keeps rising in price, while the locals keeps fighting against the more frequent floods.

MOSE consists of 78 individual mobile barriers which are designed to rise up from the water to withstand high tides of up to 3 meters above normal sea level.
(Photo: Consorzio Venezia Nuova)

Normal, yet unusual

“I need a cup of coffee,” says an elderly woman as she enters Dodo Caffè, exhausted after walking through the water masses that have taken over the streets of Venice. “I’ll stay here and wait for it to stop flooding,” she says jokingly to Eduardo “Dodo” Milliaccio, the owner of Dodo Caffè, who can only smile in compassion with the elderly woman. “This year it’s different. It has been going on for 15-17 consecutive days,” he answers.

Everyone passing by the small café in the outskirts of Venice greet Milliaccio as they walk through the shallow waters and have a few words with him as they pass. He explains that they usually stop by his café on days with high tides to catch their breath while walking through the water masses in the city to either go to their work or to their home. Today the tide is not too high, the sun is shining, and only a few of them walk in to converse over a cup of espresso.

“It happened in a few minutes,” Eduardo Milliaccio says to tell how he experienced the sea level going from 150 cm above normal sea level to 187 cm on the night of November 12. (Photo: Jesper Gundorph)

A common conversation subject between the customers and the café owner is the MOSE-project. Multiple guests complain about how they should just have activated two of the three parts ready of the MOSE on the night between the 12th and the 13th of November, where the sea rose to second ever highest of 187 centimeters, damaging buildings, infrastructure, ferries, shops and killing two people.

Avoiding a bigger disaster

The idea of closing only a part of the MOSE wouldn’t have been a good explains Monica Ambrosini: “If we would have closed off only one opening, it would have created an even bigger disaster, as the water would enter at one point, but have nowhere to exit again.”

Even though the MOSE-project is now expected to be fully functional no earlier than 2022, Ambrosini is expecting the MOSE to ready for full tests in the upcoming year to figure out other possible challenges and problems the project could be facing.

The 78 gates that MOSE consist of are all 20 meters wide but vary in hight between 18,55 meters and 29,50 meters. They weigh between 168 and 330 tons each.
(Photo: Consorzio Venezia Nuova)

The clearest and most talked about challenge the MOSE is facing is the sand that is expected to go under the big gates, whenever it is deemed necessary to raise them. The venetians are worried about the risk of the gates not being able to go back into their place on the seabed if it is filled up with sand while the gates are up.

It is an issue Ambrosini and the rest of the Consorzio Venezia Nuova are aware of. They plan to have pumps ready every 5 years to pump sand away from under the gates. Already now there are two gates that can’t go all the way down in their place due to sand, she says.

It is one of the reasons the expected costs of maintenance are thought be around €100 million every year, when the whole project is ready.

MOSE – Not A Viable Solution

In the neighboring city of Padova, hydraulic engineer, vice-chair of UNESCO International Initiative on Land Subsidence, and associated professor at University of Padova, Pietro Teatini, thinks the MOSE is not viable as the only solution to the ever-growing challenges with water in Venice.

Teatini explains that Venice is facing two different challenges that are resulting in the same problem. First challenge is the main sea levels rising due to climate change, and the second challenge is that the city of Venice is sinking 1-1,5 millimeters every year.

The venetian people continue to work even in case of high tides.
(Photo: Jesper Gundorph)

According to Teatini the increase of the industrial utilization in the 1950’s in the harbor of on the mainland side of the Venetian lagoon meant that the whole problem was accelerated, when around 40.000 m3 of water was pumped up every day.

“This led to a decrease in the pressure in the sedimentary base under the Venetian lagoon. The decrease of pressure creates a compaction of the sediments which leads to a lowering of the land surface.”

The lowering of the land above the Venetian lagoon meant that the city of Venice sunk 14 centimeters in the span of 30 years. As a result of the disaster in 1966, where Venice was hit by a high tide of record-holding 194 centimeters the practice of pumping up water from the aquifer was discontinued.

Lifting Venice Back Up

Teatini has, with a team of his, done research on the possibility of reversing the actions of the 1950’s. They have with a successful outcome looked into the possibility of putting twelve wells in a circular shape in a 10 km diameter around Venice.

The idea is to dig the wells 600-1000 meters below the lagoon bottom and from there pump 50 liters of water in each well every second. According to the calculations, they expect to be able to raise the bed of the lagoon, including the city, around 20-25 centimeters within 10 years.

Even though their research, calculation and work has come out very positive in theory, they are lacking the funds to do full-size-testing in the Venetian lagoon.

Why not look to towards the Netherlands?

Matteo Secchi, President of the local union Venessia.com who are fighting for the rights of the venetian people, doesn’t understand how the government chose to go with the solution they have, instead of looking towards the Netherlands for inspiration.

Matteo Secchi and the rest of Venessia.com are questioning the work process on the MOSE-project, and they are planning to support more protests against the project.
(Photo: Jesper Gundorph)

“Why didn’t they ask the Netherlands for advice? They live below sea-level, and they are able to keep the North Sea from breaking through their barriers,” Secchi says.

Monica Ambrosini explains that when they in the 1990’s decided to go with the current choice of design, they had aesthetics play a part in the decision-making, as they wanted to go with a solution that wasn’t visible when not activated. They didn’t want the MOSE to be part of the picturesque nature of the Venetian lagoon.

According to Secchi, the Venetian people don’t care about the aesthetics: “We don’t care if it’s ugly or not. We just want to save our houses, our apartments. We just want to save our city. Why they chose a more expensive and more complicated solution I will never understand.”

Whether they like it or not, it is too late to turn around says Ambrosini:
“We have spent too much money and time on this project, so it would not be a good idea to stop at this time.”

Teatini concludes that only time will tell, if MOSE will last the next 50, 100 or 200 years.

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