Last of the Venetians expected to vanish within 25 years

The population of Venice is draining away. Forty years after the most disastrous flood in its history, Venice today confronts an even more pernicious threat to its future: the steady departure of its residents.

Demographic experts cited by La Repubblica, the Roman daily newspaper, claimed that the last true Venetian would be turning off the lights sometime about 2030.

While Venice has never been more popular for tourists, with 50,000 visiting every day, the Venetians have been leaving ever since that black day on 4 November 1966, when filthy salt water from the lagoon inundated the city to more than one metre and stayed there for 24 hours.

That year the city's population was 121,309, but within a decade it had dropped by one-sixth to just more than 100,000. And the loss has been relentless ever since. Today it stands at 62,027, barely half what it was at the time of the flood.

And if anything the exodus is accelerating. A total of 1,918 left in 2005 alone. It is feared that the future decline will be from 2,000 to 2,500 people per year. Unless something is done to reverse or at least slow the trend, the city will empty out somewhere between 2030 and 2037.

Even the city's authorities are a little alarmed. "We're getting beyond the danger level," Mara Rumiz, the municipal councillor for housing, said. "After this, Venice will no longer be a normal city but will metamorphose into a mere tourist destination."

What makes the city government particularly gloomy is that Venetians are not simply quitting the watery city for dry land: since the 1980s, the industrialised and densely populated Mestre area on the mainland has been shedding population at an even greater speed than the city.

But it is Venice itself that is the heart of the problem, and it has been aggravated by decades of indecisive and ineffectual government. The most basic problem for anyone living in the city is flood water. "In 1900, St Mark's flooded around 10 times a year; now it is around 60 times a year," Anna Somers Cocks, the chairman of the Venice in Peril fund, said. "The water level in the city is permanently too high nowadays - 25cm above the mean water level reference point established in 1897 - and this is eating away at the brickwork."

Yet although the menace of the high water has been obvious for decades, it is only in the past four years that work has begun on an underwater gates system that is designed to save the lagoon from high tides. And the left-wing mayor of Venice, Massimo Cacciari, is still doing all he can to get the work stopped.

Sixty floods per year add a huge burden of maintenance for Venetian householders. If they are minded to sell out, however, the market is buoyant, thanks to foreigners willing to pay top prices for a holiday nest.

The tourist invasion has forced the closure of the bakers, grocers, butchers and other everyday shops on which residents depend. They are replaced by fashion boutiques, fast-food outlets, souvenir shops and stalls selling Venice carnival masks - made in Taiwan.

"It's not a happy picture," Mr Cacciari said. According to the mayor, a central problem was the lack of affordable housing. The city is building 1,400 flats at controlled prices. But that may not be enough, Mr Cacciari admitted. "We must break out of the tourism monoculture," he said.