Venice and the MOSE system

Venice is an architectural masterpiece built on several islands lying inside a lagoon. The city of Venice is full of cultural and historical heritage making it a major part of the UNESCO World Heritage sites. The geographical location of Venice causes a periodical flooding phenomenon known as acqua alta. Acqua alta is threatening historical preservation as well as interfering with the everyday life of citizens and tourists. After a long debate, the government has decided the best way to stop acqua alta and preserve the city is by using MOSE. MOSE is a series of mobile dams that are strategically placed in the three inlets of the lagoon. When the water level of the Adriatic sea is too high the MOSE system will raise the flood gates which acts as a dam from the sea to the lagoon stopping acuqa alta. After the water levels reach above 110cm the MOSE system is not completely effective and at least some flooding will occur. Even with waves that reach over 110cm the MOSE system will help prevent erosion of the sediments which lie under the city of Vencie because the majority of the waves momentum will be broken on impact with MOSE.

The MOSE system is a highly controversial topic because when the gates are raised, all entrances and exits to the lagoon will be blocked. Having the lagoon blocked causes a negative impact on the economy of Venice due to cargo ships having to be delayed which means the economy suffers. Without the MOSE system the harbor would still be fully operational but the city of Venice will be flooded meaning the city is shutdown. When the city of Venice is flooded the economy also suffers and the city has the potential for cultural heritage losses from flood damage. The article mentions various models that have been developed to represent decision making problems under ambiguity. The main model the article talks about is the Choquet Expected Utility model which is applied to MOSE mobile barriers given the ambiguity affecting the possible forecasts of the environmental parameters. The environmental parameters being the rise in sea level, the frequency of acuqa Alta, and giving uniquely determination of its economic impact. 

During our stay in Venice we saw the wooden walkways that are placed around St. Mark’s Square and the Rialto area to be used in times of acuqa Alta when the city intentionally floods these areas. The wooden walkways are designed to help keep St. Mark’s Square open in times of acuqa Alta when the rest of Venice shuts down. We also met with an engineer that works on the MOSE project and heard his thoughts on the project. It was interesting to learn that the project will cost 5 billion Euros and the gates are expected to last for over 100 years. The MOSE system will hopefully be a long term solution to slow the erosion of the sediments under the city of Venice even if that means having economic losses because shipping cargo has to wait to enter the harbor. They expect to only need to use this system about six times per year. 

Pictures are from Venice and show the water and one is from the meeting with the city engineer.