Four years after the first stone was laid for a costly and controversial flood barrier to protect Venice, its architects say that they are winning the fight to stop the city sinking.

Only from the air do you realise the true scale of the challenge to stop the city disappearing under water. This week The Times was offered an exclusive helicopter tour of the emerging flood defences along the narrow littoral of beach and sea wall that stretches 46km (28 miles) and marks the edge of the lagoon and the beginning of the Adriatic.

The Doge’s Palace and the campanile (belltower) of St Mark’s shimmer only 6km away. At the moment the sea is calm and the lagoon – the largest wetland area in the Mediterranean – looks idyllic. But below you can clearly see the three yawning gaps or inlets that puncture the thin, strung-out line of lagoon defences – at the Lido port entrance, at Malamocco and at Chioggia. When the Adriatic rises it surges through unstoppably, swamping St Mark’s Square with increasing regularity. Venice is now flooded more than a hundred times a year, compared with only seven times a century ago. It is a consequence of rising sea levels and the subsidence of the lagoon city’s foundations, aggravated by the extraction of ground water by mainland industrial plants at Marghera and Mestre.

There are fears of a repeat of the floods of 1966, when the level reached 194cm (7ft 4½in) and water, oil and sludge-damaged monuments and works of art, sparking international rescue efforts and the founding of the Venice in Peril organisation.

Some predict that Venice will disappear under water altogether within a century, fulfilling Lord Byron’s prophetic verse: “Venice! Venice! When thy marble walls are level with the waters, there shall be a cry of nations o’er thy sunken halls, a loud lament along the sweeping sea!”

The solution is the flood barrier, Mose (Moses), which apart from recalling Moses’ biblical parting of the Red Sea is an Italian acronym (for Modulo Sperimentale Elettromeccanico). The project, which is costing the Italian State €4.2 billion (£2.8 billion), is entrusted to a consortium of Italian engineering and construction companies, the Consorzio Venezia Nuova. It involves 79 300-tonne hinged steel panels or “buoyancy flap gates”, which most of the time will lie beneath the water but will fill with compressed air when the high-tide alarm sounds, closing off the three inlets. There are 700 workers at the three construction sites, a workforce due to double as completion approaches in 2012. A €1.5 million simulator at Malamocco shows how the locks will allow shipping to pass when the lagoon is blocked off.

The Moses project was finally approved in January 2003 by the Comitatone, a mega-commitee involving government ministries, the Venice council and the Veneto region authorities. When Silvio Berlusconi, then the centre-right Prime Minister, laid the foundation stone at Malamocco three months later he insisted: “There is no way back.” After initial doubts the centre-left Government of Romano Prodi has also swung behind Moses. Yesterday the Administration released a further €300 million, hailed by the consortium as a sign that the project has “passed the point of no return”.

For those who have opposed the project from the start, the fact that only preparatory work has been completed is its weak point. Since 2003 work has been held up by environmental protests, European Commission investigations and even doubts raised from within the Government itself by the Environment Ministry.

The doubters also include Massimo Cacciari, the Mayor of Venice, who has issued a 400-page volume of “noninvasive” alternative schemes. A vocal “No Mose” protest group of environmentalists, conservationists and left-wingers – including the mayor’s radical nephew, Tommaso Cacciari – insists that Moses is “a white elephant to channel public funds to a private consortium” that was never put out to tender, an example of “corporate greed” and political cronyism hand in glove. Their main objections focus on the threat to the lagoon’s ecological balance. “The barrier is already damaging habitats and species protected by EU directives,” said Luigi Lazzaro, of Legambiente, the environmental pressure group.

The protesters, who have collected 12,500 signatures opposing Moses, are chased away by security patrol boats if they approach the dam construction sites too closely. But they have not given up. “The consortium says 31 per cent is complete, but what has been done can be dismantled or put to other uses,” insists Luciano Mazzolin, a protest leader. But the consortium rejects allegations that it has failed to comply with Italian and EU law requiring major projects to undertake an “environmental impact assessment”.

In a further victory for the consortium this week the Committee for Safeguarding Venice, the city’s official conservation body, approved a cement platform at Malamocco that Brussels has said may damage the flora and fauna of an adjacent nature area.

“We have conducted exhaustive environmental assessments,” said Andrea Bondi, a consultant engineer to the Moses project. “The beauty of the scheme is its flexibility”.

At her office in an historic palazzo next to the Rialto bridge, Maria Giovanna Piva, head of the Venetian Water Authority (Magistrato alle Acque) – the first woman to hold the post in its 500-year history – also dismissed the protesters’ claim that maintenance of the flood barrier after completion will cost billions of euros annually. “We put the figure at €18 million initially, probably less later,” she said. Next month the Water Authority, which is part of the Ministry of Infrastructure and backs Moses, will join the consortium in offering twice-daily “information trips” by boat out to the dam construction sites. The protesters’ idea of closing down the Venice cargo port and banning cruise liners as an alternative is absurd, she said.

Ms Piva added that engineers from Venice were in regular contact with those running or planning flood barriers in Britain, Russia and the Netherlands and that the Moses project was complemented by other measures such as raising the city’s foundations and dredging and cleaning canals.

“We are doing this not just for Venice and Italy, but for the world,” she said. “Venice is a world treasure.”

Rise and fall

1420s Venice, rich from trade, conquers Italian territories from the Adriatic almost to Milan

1489 Acquisitions including Cyprus make Venice the leading maritime power in the Mediterranean

1508 Pope Julius II forms first league of Cambrai with France, Spain and Austrian Habsburgs against Venice

1509 The Venetians are defeated at Agnadello. Pope Julius and the Habsburgs appropriate much of Venice’s mainland territory

1573 Venice cedes Cyprus to Turkey

1587 The Banco di Rialta, first public banking system in Europe, opens in Venice

1588 Antonio da Ponte begins the Rialto Bridge, crossing the Grand Canal

1637 The world’s first public opera house opens in Venice. The city becomes key destination in the Grand Tour

1669 The Turks evict Venice from Crete

1797 Napoleon deposes the last doge and Venice is handed over to Austria

1866 Austria is defeated in the Seven Weeks’ War. Venice is handed over to the Kingdom of Italy

Source: www.historyworld.net

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