A new ISLAND is born: a secret islet appears off the coast of Venice – and it already has a thriving ecosystem

The warm waters and sandy beaches of the Venice Lagoon have attracted tourists from around the world for hundreds of years.

Now locals and visitors have an extra place to set up their deck chairs as a new island forms near the historic town.

Previously, the secret islet of Bacan only formed during the summer months before being washed away by winter storm surges.

But thanks to a new flood barrier, this treasured refuge for tourist-shy residents has become a permanent feature of the lagoon with its own thriving ecosystem.

Measuring 250 meters long and 10 meters wide, the sandbar is covered with a thick layer of vegetation.

Bacan is now home to a range of marsh plants like samphire, rushes, native flowers and small salt-tolerant cedars called tamarisk.

Thanks to new roots holding the soil in place, the island has not disappeared since 2020, when the flood dam’s operators went on vacation during a winter surge.

However, even as locals celebrate the birth of a new beach, some experts warn it could be a worrying sign for Venice’s fragile ecosystem.

In the shallow, brackish Venice Lagoon, small sandy islands can form even as a result of slight disturbances caused by swirling currents.

It takes so little time for the tides to form a new island that the locals have a saying: “Palo fa palugo” which means “a pole makes an island”.

What makes Bacan unique among this ever-changing archipelago is its seasonality.

During the warmer months, when the water level dropped, Bacan rose from the waters where its quiet, inaccessible beaches made it a popular spot with residents of Castello, the southernmost district of Venice.

Then, in winter, as the floods so often flood the city, the island would simply be washed away.

Yet the islet has remained resolutely above the waves for the entirety of the past four years.

According to Giovanni Cecconi, an engineer from Ca’ Foscari University of Venice, the island’s stability is a by-product of the MOSE anti-flood dam that has protected the city since 2020.

The MOSE barrier, which Mr. Cecconi worked on, is a series of movable gates that rise to separate Venice from the Adriatic Sea during winter waves.

Venice has always experienced flooding when strong winds from the Sirocco combined with high tides to raise the water level above the city streets.

However, in recent years these periodic floods appear to be becoming more frequent and more severe.

In 2019, one of the worst floods on record plunged 80% of the city underwater, with sea levels rising 1.8m above normal.

The MOSE barrier helps prevent these deluges by temporarily isolating the lagoon from the Adriatic when heavy flooding is forecast.

However, a side effect is that these powerful tides no longer wash away the sands of Bacan.

Mr Cecconi told The Times: “By raising the barrier in winter to stop high water, the island is protected from the waves that previously eroded it.

The island’s location may also explain why it has grown so much since MOSE was implemented.

Located opposite one of three lagoon entrances equipped with flood defenses, Bacan can benefit from increased current during the summer months.

Mr Cecconi says: “The barrier… speeds up the flow of water into the lagoon when it is open, meaning more sand comes in, helping to maintain Bacan. »

And as the island becomes more populated, its soils will become more stabilized, making it more likely to survive future erosion.

“This is a new ecosystem which shows that the lagoon can evolve in a positive way alongside human intervention,” adds Mr. Cecconi.

However, not all experts are convinced by Mr Cecconi’s explanation.

Professor Adrea D’Alpos, an expert on coastal zone developments at the University of Padua, told MailOnline it was a mistake to attribute Bacan’s formation entirely to MOSE closures.

He states: “The development of this narrow strip of sand and mud, now colonized by vegetation, is mainly the result of several overlapping processes acting at different spatial and temporal scales.”

Furthermore, Professor D’Alpos emphasizes that Bacan’s training actually began well before the first activation of MOSE in October 2020.

This means that the flood barriers surrounding the city are likely just one part of a larger, more complex whole.

Professor D’Alpos is also not convinced that Bacan will become a year-round beach for future generations of Venetians.

He said: “I wouldn’t describe it as permanent. Although the islet is currently growing and its elevation is now above mean sea level, its long-term persistence remains uncertain.

Critically, Professor D’Alpos also argues that the development of a thriving ecosystem on Bacan is not necessarily a sign that nature is recovering.

While the MOSE flood control dam is essential to the survival of Venice, it also has a profound impact on the environment.

More importantly, by preventing high tides from washing over land, the barrier prevents sediment from being transported to the salt marshes surrounding the city.

“Although MOSE activations are essential to protect Venice from high tides, they significantly reduce tidal peaks during storm surges and significantly limit the extent and duration of salt marsh flooding,” explains Professor D’Alpos.

“This in turn decreases sediment deposition on the marshes, threatening their long-term survival.”

Studies have shown that Venice’s salt marshes owe 70 percent of their growth to these winter storm surges.

Venice’s salt pans have been slowly disappearing for centuries, in part due to poor waterway management dating back to the 1500s, when water was diverted from the lagoon.

Since salt marshes absorb 30 times more CO2 than a forest, their disappearance would be a major issue for the planet.

And because salt marshes lessen the impact of storm surges and reduce flooding, anything that would limit their extent would also be a big problem for Venice itself.

So while the new life on Bacan might be good news for beachgoers, it could be a sign of worrying changes to come.