Flood, desolation, ruin-these have all been predicted as the fate of the world's most beautiful city. But a vast international rescue attempt is already under way. The British alone have restored the Church of San Nicolo dei Mendicoli to its original glittering brilliance, cleaned the principal entrance to the Doge's Palace and are contributing to the renewal of the marvellous Cathedral of Torcello. The Venetians themselves are tackling the problems of water and air pollution, renovating houses in the oldest parts of the city and taking measures to prevent the city sinking any further. But the greatest menace still remains - flooding from the sea. Can the Italians solve the problem? Can they learn from the Thames Barrier? How much have the city's chances of survival improved in the last decade?