VENICE'S CONTROVERSIAL flood barrier scheme is set to go ahead.
The Italian government last week finally ended years of wrangling over environmental impact assessments when a special committee charged with protecting the city from flood voted to proceed to final design.
The £1.5bn barrier scheme will hold back tide surges of up to 2.75m using 79 semi-buoyant flap gates in the three inlets to the Venice lagoon.
A further £1bn is to be spent on an extensive series of flood prevention measures, known as the 'Insulae' project, and will include raising public areas such as St Marks Square which currently floods 100 times a year. Local flood walls will also be built to protect monuments, housing and commercial premises from tides of up to 1m without using the barrier, so reducing the environmental impact of sealing off the lagoon.
The government committee has insisted that three conditions are met by 31 December this year before work goes ahead: the tidal model must be proved to be 'sufficiently reliable'; further checks must be made on the morphological effects of closing off the lagoon; and the results of this work must be reflected in the detailed design of barriers.
If these conditions are met work should begin within two years and be completed by 2010.
The barrier and Insulae project were conceived in 1984 by the Consorzio Venezia Nuova group of private sector contractors in response to research prompted by the catastrophic flood of 1966. The flap gates, totalling 1.76km in length, will be hinged from housings set flush to the lagoon bed and will be raised by compressed air.
But bitter opposition to the barrier from Italy's environmental lobby has delayed construction. Alternative schemes using soft engineering within the lagoon were promoted by environmental groups.
Scheme promoter CVN said its detailed studies and those of numerous international experts have 'proved that the only effective solution against all flooding conditions consists of the barriers with a limited number of closures - and the Insulae'.
CVN's technical director Maurizio Gentilomo said the gates would be raised around 80 hours a year for to the predicted seven tides in excess of 1m.