Anna Somers Cocks, Chairman of Venice in Peril, said, "It is reaching the edge of the stone base now and the water is beginning to lap against the brickwork which is why the houses are all desperately damp."

For those living and working here, maintaining an old, constantly damp house and buying food that has to be brought in by boat is not cheap.

Gherardo Ortelli, History Professor, University of Venice, said, "When two young people marry here, they have to leave. They cannot afford to live in Venice."

But compared with a declining population, the chief threat to Venice comes from the water.

Huge liners create a wash that erodes foundations. Smaller vessels also cause waves that lap up against stone bases.

Somers Cocks believes the government needs long-term plans to save Venice.

Anna Somers Cocks, Chairman of Venice in Peril, said, "We need a plan for 50 years, even a hundred years."

Scientists believe Venice is likely to survive, because it has all that's necessary within it to carry on forever. But they say it's a question of deciding what kind of Venice should survive.