MOSE, the mobile barriers system
The Mose System to safeguard Venice from high waters consists of mobile barriers able to temporarily separate the lagoon from the sea and protect Venice from both exceptional destructive events and more frequent events. It is being constructed at the lagoon inlets of Lido, Malamocco and Chioggia, the three openings in the barrier island through which tides propagate in the lagoon.
The mobile barriers consist of rows of gates. In normal tidal conditions, the gates (a type of pontoon) rest in housing structures on the bed in the inlets, completely invisible and without modifying exchanges between sea and lagoon. They are raised only when necessary to block the incoming tide and avoid flooding the lagoon and built up areas.
When the gates are in operation, the continuity of port operations will be guaranteed by a lock for large shipping already constructed at the Malamocco inlet.
Mose can protect the lagoon and its cities and towns from tides of up to 3 m.
In the future, the phenomenon of high waters could, in fact, be further aggravated by the predicted rise in sea level resulting from climate change. With respect to this problem, Mose (together with reinforcement of the barrier island, the narrow strip of land separating the lagoon from the sea) has been dimensioned on the basis of a precautionary criterion to cope with eustatism of up to 60 cm, in other words, even higher than recent scenarios estimated by the international scientific community.
Management of Mose is flexible enough to cope with an increase in high waters in various ways, depending on the characteristics and scale of the tidal event. Depending on the situation, the defence strategies can involve simultaneous closure of all three inlets in the event of an exceptional event or alternatively and according to the winds, pressure and amplitude of the forecast tide, differentiated closure of the inlets, or again, partial closure of each inlet, as the gates are all independent.
THE PARTIES INVOLVED
The Venice Water Authority is a branch of the Ministry of Infrastructure and Transport. Its responsibilities include activities to safeguard Venice and its lagoon according to the Special Law for Venice.
Implementation of the measures is delegated to a single body able to operate according to a systemic vision of the lagoon ecosystem, with a global project integrating protection from high waters with restoration of the naturalness of the lagoon.
This implementing body is the Consorzio Venezia Nuova consisting of national and local Italian companies and working under the surveillance of the Water Authority which has the role of policy, control and surveillance.
