Mose, Venice, Italy

Since the early 1900s, high waters have become increasingly frequent as a result of subsidence and rising sea levels. Flooding causes inconveniences to residents and damages the architecture and buildings. There is also an ever present risk of a catastrophic event such as the flood of 4 November 1966 when Venice, Chioggia and other built up areas in the lagoon were completely submerged under more than a metre of water.

Modulo Sperimentale Elettromeccanico - Mose - consists of rows of hinged gates which, in normal tidal conditions, contain water and are invisible in housing structures at the bottom of the three inlets. When a high tide is forecast, compressed air is pumped into the gates to empty them of water. This causes them to rise above the surface, creating a continuous barrier separating the sea from the lagoon for the time necessary.

Four tidal defence barriers are being constructed. Two of these will be installed in the Lido inlet, the one nearest Venice. With 21 gates in the north channel, 20 gates in the south channel and an intermediate island linking the two barriers. Another barrier with 19 gates will be installed in the Malamocco inlet. Finally, one barrier with 18 gates will be constructed in the Chioggia inlet. The previous depths and cross sections of the inlets will not be altered by the structures. Small craft harbours connected to locks will allow vessels to enter the lagoon when the barriers are raised. These will include small locks for pleasure and fishing boats at Lido and Chioggia and a lock at Malamocco for large ships heading for the port.

Mose will defend Venice and the lagoon from tides up to 3 metres high and from a rise of up to 60 cm in the sea level over the next 100 years. The city will also be protected from a certain yet unforeseen catastrophic event in the future. Mose also eliminates the inconvenience and financial damage caused by the most frequent high waters and improves the quality of life in general, revaluating ground floors and diversifying the intended use, including the establishment of new activities and workshops.

Deerns was responsible for developing the mechanical system design and coordinating the electrical system design.