The Queen of the Adriatic is sliding into the sea. Can MOSE flood barrier fight the laws of nature?
“Venice is a great treasure for the whole of mankind and it is indeed a great shame if the latest knowledge is not applied to saving Venice” – Roger J. Braithwaite
The impacts of sea level rise in the Venice’s lagoon
Venice sits in a lagoon, separated from the Adriatic Sea by a series of barrier islands. Centuries of human intervention — including the diversion of rivers, widening of the lagoon’s entrances and dredging of channels to accommodate shipping, and the draining of mudflats for construction and agriculture — have disrupted the lagoon’s equilibrium with the sea [1].
Sea level rise (SLR) represents the main threat for the survival of Venice, emerging today only 90 cm above the Northern Adriatic mean sea level.
Sea level rise is a significant consequence of climate change and global warming. At present Venice is sinking at 0.05 cm/year and the 25 cm of SLR occurred over the 20th century has increased the flood frequency by more than seven times. During the 21th century, global average sea level is expected to rise considerably faster that in the 20th [2] and the flooding events of 110 cm above datum or more could increase to 20–250 times per year with respect to the present annual frequency of 4 times [3].
![Frequency of tides higher than 60 cm at Venice obtained from the sea level records over the last 40 year for the three selected SLR scenarios [3].](https://d3.harvard.edu/platform-rctom/wp-content/uploads/sites/4/2016/11/Graph-3.png)
MOSE: a barrier to hold back the tide
Finally, in 2001 the Italian government decided to put into action the most ambitious of the engineering solutions known by its Italian acronym of MOSE (MOdulo Sperimentale Elettromeccanico, Experimental Electromechanical Module). The project is an integrated system consisting of rows of mobile gates situated in the three inlets through which water enters and leaves the lagoon. Gates are inserted into their concrete foundations on the bed of the Venetian lagoon and are able to be opened and closed separately to control the flow of water and temporarily isolate the Venetian Lagoon from Adriatic Sea tides of up to 3 meters (9.8 ft) [1].
The Consorzio Venezia Nuova [4], made up of a group of national and local construction companies, is responsible for the work on behalf of the Ministry of Infrastructure and Transport – Venice Water Authority. Construction began simultaneously in 2003 at all three lagoon inlets and the gates are expected to be fully operational between 2018 and 2020, later than the originally anticipated 2016 completion date. The MOSE project is estimated to cost €5.5 billion, up €1.3 billion from initial cost projections [1].
To support and control the billionaire capital investment for the construction of the gates, Consorzio Venezia Nuova instituted the MOSE control center. The center has been simulating the control of the gates since 2011, collecting data that enables the creation of mathematical and statistical models that can be entered into the decision support system. The factors being considered are wind, water level, waves, pressure and fresh flood from the rivers [5].
What’s next
Supporters and opponents of MOSE are still debating in local newspapers and media. The Venice Water Authority has done an important step forward to preserve a masterpiece of the human heritage from the impacts of climate change and sea level rise, but more actions need to be taken considering that we only have predictions of what those impacts could be in the next century.
First of all, the Venice Water Authority has to make sure that no further delays will affect the completion of the project. Secondly, additional measures suggested by many scientists should be put in place, such as narrowing the large canals that enter the city’s harbor, reinforce the coastal, raise special quaysides to protect historical buildings from high floods, and improve the pavement of the lagoon [6].
Furthermore, once the MOSE gates will be fully operational, Venice Water Authority should consider to add more resources to the MOSE control center so that it can operate 24 hours a day and manage flood emergency promptly.
Finally, Italian Turism Authorities should run sensitization campaigns and raise funds from global organizations and private funds to support the Venice’s cause. A successful example is the UK-based Venice In Peril Fund that supports restoration and conservation work in the city. In the words of the chairman of the fund Jonathan Keates, “If the thought of Venice sinking captures the imagination, then it should be as a wakeup call to save the city as an essential basis of the civilization we cherish. The world owes huge debts to Venice, including modern systems of democratic government and the printed book.” (793 words)
References
- Nicola Nosengo, “Venice floods: SAVE OUR CITY!”, Nature 424, 608-609, 7 August 2003, [http://www.nature.com/nature/journal/v424/n6949/full/424608a.html], accessed October 2016
- Gregory et al., “Oceanic Climate Change and Sea Level”, IPCC 2007, accessed October 2016
- Carbognin, L., Teatini, P., Tomasin, A. et al., “Global change and relative sea level rise at Venice: what impact in term of flooding”, Clim Dyn (2010) 35: 1039, [http://link.springer.com/article/10.1007/s00382-009-0617-5], accessed October 2016
- www.consorziovenezianuova.it
- Windsor, Antonia, “Inside Venice’s bid to hold back the tide”, The Guardian Retrieved 2015-06-24, [https://www.theguardian.com/cities/2015/jun/16/inside-venice-bid-hold-back-tide-sea-level-rise], accessed October 2016
- Paolo A. Pirazzoli, Georg Umgiesser, “The Projected “MOSE” Barriers Against Flooding in Venice (Italy) and the Expected Global Sea-level Rise”, Journal of Marine Environmental Engineering 8.3 (2006): 247-261, accessed October 2016
- “Venice Hasn’t Stopped Sinking After All”, Scripps Institution of Oceanography News (blog), 2012, [https://scripps.ucsd.edu/news/1860], accessed october 2016
- “Venice: sliding down, tilting east”, Nature 483 512, 29 March 2012, [http://www.nature.com/nature/journal/v483/n7391/full/483512a.html], accessed October 2016
Interesting topic of choice, and one that brings to mind many magical memories or images of Venice to most of us! Since I was a little kid, I have been hearing how “Venice is sinking, Venice is sinking” – it is great to finally read about how the Italian government has taken steps to implement MOSE and take back control.
I fully agree with your suggestions – especially #3. Venice benefits from holding a key place in much of the world’s cultural identity, and as such it can really leverage many types of marketing and fundraising campaigns to help its cause. The structure of the lagoon next to the sea seems like a pretty interesting engineering problem to work on, so hopefully the government could also implement additional campaigns to attract more top engineering talent on solving this issue.
Interesting!
I assume MOSE was used because there is no visual pollution? The Delta Works are very impressive engineering constructions but would not fit in a historic context…
You mention that “Venice sits in a lagoon, separated from the Adriatic Sea by a series of barrier islands. Centuries of human intervention — including the diversion of rivers, widening of the lagoon’s entrances and dredging of channels to accommodate shipping, and the draining of mudflats for construction and agriculture — have disrupted the lagoon’s equilibrium with the sea”. Would it be a good idea to restore the historic coastline to better protect the city?
Great topic of choice. Other major cities are also at risk of raising sea levels…including New York, Hong Kong and Boston! As such more local resources and international expertise should be placed to work in places like the MOSE control center in order to finds ways to adapt and learn from the outcomes of these projects with aims to help innovate and find effective solutions to other cities at risk. However, on a much bigger scale major countries including the United States should find effective ways to jointly deal with these issues and push for climate change measures in climate change conventions. More awareness should develop on the topic. I agree with your campaign suggestion for financial support as well as personal carbon footprint reduction.
There was a really scary sensationalist headline on Facebook sometime last year that said something like “Boston: The Venice of the West” but I think it was completely untrue. Basically focused on the fact that Back Bay is technically a man-made neighborhood and below sea level.
Fantastic post. I spent a summer in Venice and agree with you that its cultural legacy is well worth the billions of dollars being invested to prevent it from sinking! At €5.5B, MOSE seems like an incredibly expensive undertaking, but I’m sure there is a strong business case (beyond cultural relevance) to warrant investment. After all, if Venice sinks (literally), so does its economy (figuratively). I’m curious to learn more about the other initiatives the Italian government has proposed to solve this issue? Are there any solutions that are less capital intensive and more flexible (i.e., that can be instituted quickly in emergency situations)? What can Italy learn from other coastal geographies at risk of sinking, and vice versa?
Great post! I’ll need to visit Venice before it goes completely under…In the aftermath of Hurricane Sandy in 2012, a similar project was proposed to protect the New York City coastline from tidal flooding due to storm surge. There were obviously both proponents and critics, but they each could have something to learn from the MOSE example if it eventually is constructed. Unfortunately, it may take another disaster to garner the support needed for these types of massive infrastructure projects. I fear that people may have short memories and when this is actually brought to the drawing board it will not gain enough support. This may even be true for the MOSE project in Venice – unless a clear disaster (loss of historic artifacts, buildings, etc.) occurs, it may be difficult for this project to surface to air.