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AA.VV.
20030612 Is a Dangerous Monster Growing in the Lagoon of Venice?
15 Gennaio 2008
Articoli e saggi
by Edoardo Salzano and Anthony Zamparutti. Paper presented and distributed at 37th International Making Cities Livable Conference, Siena, 15-18 June 2003.

Two threats hang over Venice. The first comes from inside: the city’s crawling transformation into a chaotic “Disneyland”. The second comes from outside: it is represented by the “MoSE”, a huge dam project whose foundation stone was laid by Mr. Berlusconi (who else?) some weeks ago.

The MoSE (from Experimental Electromechanical Module) is a very “hard” and gigantic system of mobile barrages (they entail huge permanent installations) to block water at the three outlets between the Lagoon of Venice and the sea (the bocche di porto). The Lagoon’s environmental equilibrium depends on the exchange of sea and brackish water through these outlets. This includes the equilibrium of the waters, of vegetation, and of fauna in this precious natural environment. The MoSE would automatically block the access of seawater when tidal surges threaten to flood some of the city’s inhabited areas.

Why is this system judged by many to be of uncertain utility, harmful for the activity of Venice’s port (one of the main economic resources of the city) and devastating for the ecological equilibrium of the lagoon? In short, why do many consider the “MoSE” to be a “Mo(n)S(t)E(r)”. We will try to explain.

The problem: “Acque Alte”

Venice was built on low islands and sandbanks in the middle of a rich coastal lagoon. For over 1,000 years storm surges have washed exceptional high tides into Venice’s squares and alleys. Venetians call them acque alte – high waters – and, typically, they last two to three hours at a time.

In November 1966 pounding rain and an exceptional wind-swept tide flooded nearly all the city streets for 24 hours. The storm focused world attention on Venice. The reason? Venice had “sunk”.

Since the early 1920s mainland factories have tapped underground freshwater, depressing the land under Venice in the process. By the time pumping was finally stopped in the 1970s, Venice had sunk by about 12 centimeters (almost five inches) – a small but important altitude change for a sea-level city.

In addition, deep shipping channels were dredged through the lagoon’s three inlets to transport raw materials – including crude oil for a neighboring petrochemical complex. The deeper channels brought stronger currents, speeding the Adriatic’s high tides towards Venice, exacerbating flooding and eroding the lagoon’s salt marshes.

And, the final nail, the northern Adriatic has risen by about 10 centimeters over the past century.

Today waters wash across St Mark’s Square – Venice’s lowest point – 50 or more times a year. Heavier storm surges now flood higher sections of Venice, too, forcing residents to don waterproof boots to reach their offices and schools.

The “Consorzio Venezia Nuova”

The November 1966 event led to a far-sighted 1973 law to protect Venice, much discussion, and limited action. In the early 1980s, a new organization was created: the Consorzio Venezia Nuova (the New Venice Consortium), uniting private and state-owned companies vying for what promised to be fat public works contracts to protect the city.

The Italian government soon named the New Venice Consortium its ‘exclusive concessionaire’ for public works to safeguard Venice. This means that the consortium essentially holds a monopoly on state-funded work to ‘save’ Venice and protect its lagoon, for everything from strategic planning to research, project design and construction. And since 1984 the Italian government has provided the consortium with over two billion Euros to study the lagoon’s ecology and hydrology, rebuild sea walls along the lagoon’s barrier islands, restore salt marshes and much more. All without any competitive bidding.

Of course, the great prize is the “MoSE”, the system of dams that the Consortium designed and now wants to build. To stop the flooding, Consorzio Venezia Nuova (the New Venice Consortium) has proposed a gigantic dam system: a line of 78 huge metal containers – each at least 20 by 20 metres in size – nestled in underwater foundations stretching across the three inlets between the Adriatic and the lagoon (each inlet is up to half a kilometre wide). For most of the time the hollow containers would be filled with water. To stop a storm surge from the Adriatic, air would be pumped into the containers – causing them to rise like enormous teeth across the inlets.

Look here to understand better what Mo.S.E. is Ú

Money and Power

Behind the Consortium (holding 40 per cent of its shares), is Impregilo – a Milan-based construction giant that builds dams, highways and power plants in over 40 countries.

The supervision of the concessionaire provided by the national government’s office in Venice (the Magistrato alle Acque), has been weak at best. The Consortium rather than the Magistrato holds nearly all the technical capacity and knowledge. Indeed, the Magistrato has hardly ever made a public proposal that differs from the Consortium’s position.

The Consortium and its allies are masters at PR. One little event can help to understand how they are able to employ the resources provided by the Italian Government to overcome all, even official, opposition to their “MoSE” project. In December 1998, Italy’s national Environmental Impact Assessment Commission failed the “MoSE” project. The next month, four professors from the Massachusetts Institute of Technology (MIT) flew to Rome and held a press conference criticizing the decision. The dams, they said, were the best solution for Venice. They spoke, the Italian press reported, for MIT and for the ‘international scientific community’. Few papers noted that they were paid consultants to the consortium.

With its powerful, legally sanctioned role and its combination of PR savvy, technical expertise and political connections, the consortium has pushed its dam project steadily – like a steamroller.

Attempts to reform the state’s curious institutional structure in Venice have come to naught. For example, a 1995 law ended the system of exclusive concessionaire. The Italian Senate the next year passed a resolution calling on the government to carry out this law immediately. Nothing happened. Nor has Italy’s government created an independent strategic planning office for Venice and its lagoon, despite official decisions to do so.

Even European law has been interpreted in unexpected ways. Responding to the Green Party and Italy’s leading environmental group Italia Nostra in 1999, the European Commission opened an investigation into whether EU directives requiring competitive bidding for government contracts had been violated. Brussels initially took a hard line. But two years later the commission closed the case, accepting a proposal from the Italian government: components of the dam project (perhaps worth half its total value) would be open for bidding, but the bidding would be organized not by the government but the Consortium. Thus, the concessionaire was given even more power.

Why we call it “A Dangerous Monster”

To understand why we call the Mo.S.E. “A Dangerous Monster”, we must note that the equilibrium of the lagoon has depended for centuries on daily work to manage its numerous elements (the length and depth of the thousands of canals, characteristics of the vegetation, defence of the coastline, extension of the brackish basin, level of sediment supplied by the rivers).

This human intervention has for centuries protected and maintained a precious natural environment. Only thanks to this control has it been possible to defend the lagoon from the two natural destinies it could face: to become a swamp and eventually mainland, if the sediment flows were to prevail, or to become an open bay, if the force of the sea was to prevail.

Only a modern systemic vision allows us to preserve that equilibrium today. The solution to the exceptionally high tides (acque alte) is closely connected. As noted above, these acque alte have become steadily more aggressive as a consequence of several factors:

- the (now ceased) extraction of underground waters for industrial purposes in the Marghera industrial plants;

the reduction of the area where the tide can expand (caused by filling in parts of the Lagoon and the closure of fishing areas to the tides);

- the gigantic increase in the cross-section of shipping channels, allowing high tides to rush towards the city (in particular through the oil tanker); and finally

- a rise in the sea level (due to the global climatic events).

In the debate over the “MoSE”, local political forces concerned about the environment and interested in a sustainable development are opposed to those interests seeking economic opportunities linked to the public works. This debate can be summarized in the contrast between two projects: the MoSE and a low-impact alternative that has never been considered at official level.

Very schematically, the alternative approach has as its primary aim re-balancing the complex system of the lagoon, by acting on the whole set of elements that compose it. In a recent document (see in Annex) the main lines of the project include:

1. Reducing the depth, width and wind exposure of the Lagoon's three outlets to the sea. These measures can be compatible with current port traffic, and they would be experimental, gradual and reversible.

2 Completing work to raise the lowest parts of the city. The Venice City Administration is now systematically raising low points of the city as it undertakes urban maintenance, By raising and protecting low areas such as St. Mark’s Square, high-water flooding events could occur an average of less than 4 times a year, in most cases for only a limited duration and for only a small part of the city.

Together, these two first types of actions would reduce current flooding events to an average of only once every five years.

3 Removing oil tanker traffic from the Lagoon - as specified under Italy's 1973 special law for Venice - and building a dock along the Lido, outside the Lagoon, for the largest cruise ships that visit Venice would allow a further reduction in the depth of outlets and of shipping channels, eliminate additional flooding events, and help restore the Lagoon's environmental equilibrium.

Other vital actions are needed to protect this World Heritage Site: the Lagoon's morphology and its hydrodynamics need to be restored, water pollution in the Lagoon and its water basin should be reduced, and the production and movement of dangerous goods in the Lagoon should be stopped. (from the Appeal to UNESCO by the Committee to Save Venice with its Lagoon – see Annex.)

The official project (Mo.S.E.) proposes a heavy engineering approach that is pharaonically expensive, of uncertain effectiveness, potentially very harmful for the relevant elements of the ecosystem of the lagoon (and for its whole equilibrium) and irreversible.

But let us look a little closer at this “Mo(n)S(t)E(r)”.

What the Consortium does not mention

The political and PR power of the New Venice Consortium has heavily conditioned all the information about the Mo.S.E.. A propaganda campaign has convinced Italian and international public opinion that the Mo.S.E. is necessary to save Venice. But the Consortium’s propaganda omits some basic information.

1 The proposed dams failed their official environmental impact review in 1998.

2 The consortium wants to dredge about five million cubic meters of the Lagoon’s bed and dump almost eight million tons of rock and 700,000 tons of concrete in its place: altogether, enough material to build the three great Egyptian pyramids at Giza! At the Lido inlet, the consortium wants to build a new, artificial island. Over 50,000 tons of sheet metal would be submerged in the form of the container-shaped gates.

3 During long closures the dams could bottle up industrial and agricultural pollution in the lagoon, which is now flushed by the regular tides. The city also lacks modern sewage treatment. The 1998 review noted that predicting exceptional high tides is an uncertain business. The dams may need to be raised following many false alarms, thus increasing pollution risks.

4 Anodes to protect the metal gates from sea-water corrosion would release over 10 tons of zinc into the lagoon a year. The toxic metal could accumulate in the food chain.

5 The consortium’s project ignores a fundamental cause of flooding in Venice – the deep shipping channels through the lagoon’s inlets. The consortium wants to open them even further, replacing their current V shapes with straight cuts across the full width of each inlet. This, warns Paolo Perlasca of WWF/Italy’s Venice office, risks accelerating erosion in the lagoon and endangering its remaining salt marshes and mud flats, which are protected (at least on paper) by the European Union’s Habitats Directive.

6 The dams would be expensive to build. The consortium estimates total costs at over three billion Euros, but critics warn that the never-before-built system could cost far more.

7 After construction, the Consortium could then reap millions of dollars a year for their operation and maintenance. These costs are also extremely difficult to estimate, as the underwater structure would face ongoing corrosion and encrustation and would require extensive maintenance.

8 The dams may not even protect Venice from flooding. Global warming and sea-level rise could make them obsolete within a few decades. Renowned Venetian climate change scientist Paolo Antonio Pirazzoli writes that the dams ‘could hardly cope with a relative sea-level rise much greater than about 0.3 meters’. In its 2001 report, the UN’s Intergovernmental Panel on Climate Change gives as its most likely estimate for 2100 a 0.48-metre sea rise. The UN’s worst-case scenario forecasts this rise occurring within a few decades. Pirazzoli also predicts that water would pass between the dams’ containers, which would be an important factor during long closures. Also, in Venice’s worst flooding (as in 1966) torrential rains and swollen rivers add to the rising tides.

No hope?

Business and politics in Italy have become in the last years two faces of the same coin. The prime minister is the country’s richest man and owner of a sprawling media empire that includes three national TV networks. Berlusconi’s government has shown little interest in the environment: last October, his environment minister sacked 23 of the 40 members of the national environmental impact commission. The government appears to have wiped negative impact assessment of the “MoSE” from its memory.

Last year the new government allocated 450 million Euros for the first tranche of the dam project: a series of ‘complementary works’, including shipping locks to appease the Port of Venice (the only major economic interest with reservations about the scheme). Berlusconi has cut all other national money for Venice: all its funds for architectural restoration, for the city’s unique maintenance needs, and more.

Flooding is not Venice’s only environmental crisis. The nearby petrochemical complex is a highly polluting time bomb. In November, a toxic fire there nearly engulfed storage tanks containing deadly phosgene gas. In addition, mechanical clam-fishing techniques are destroying the ecology of the lagoon’s shallows. And motorboats bringing tourists and cargo through the city erode the canal walls – the foundations of Venice’s palaces. All these problems need public funds to help find solutions.

In Venice opposition to the dams continues. In September 2002 both the city and the provincial councils voted against the ‘complementary works’. In December an environmental alliance called Salvare Venezia con la Laguna (Save Venice with its Lagoon) presented its strategy to restore the lagoon’s equilibrium. Unlike the consortium’s risky surgery, the environmental proposal targeted Venice’s underlying illness. And in January 2003, political parties in the city sponsored public debates on the dams and possible alternatives – alternatives that the national government ignored when it approved the “MoSE” later this year.

What Venice needs, wrote US scientists Albert Ammerman and Charles McClennan in the journal Science two years ago, is ‘fresh thinking in the search for new, alternative solutions’. In Rome’s halls of power, however, there’s only one official project.

But time is running out: in April 2003, Italy’s national government gavea final go-ahead to the dams, and Berlusconi himself went in Venice to inaugurate what he called the beginning ofconstruction. Must we conclude that “ tout les jeux sont faits ”? I don’t think so. The Consortium will be busy for a couple of years building preliminary works – not the dams themselves.

If all those who oppose the Mo. S. E. and all those that have doubts about its utility couldexplain to international public opinion the real dimensions of the problem, perhaps we could stop this project that threatens to cancel the Lagoon of Venice and its environment, not less precious than the city’s stones, palaces and campi. This is our hope.

(This paper is based on an earlier article, “Death of Venice”,

by Anthony Zamparutti, The Ecologist, London, March 2003.)

AppendixSave Venice Through Effective and Sustainable Alternativesto the "Mose" Project

This Appeal to Unesco was promoted from the “Committee to Save Venezia with its Lagoon”. The following groups support the Committee: Wwf-Italia, Italia Nostra, Verdi Ambiente Società, Sinistra Ecologista, Medicina Democratica, Camera del Lavoro Metropolitana di Venezia-Cgil, Associazione Airis, Associazione Bortolozzo, Associazione Batteria Rochetta e Dintorni, Associazione per la Difesa dei Murazzi Circolo Margaret Thatcher, Comitato Certosa-Sant'andrea Ecoistituto "Alex Langer" Del Veneto Estuario Nostro; Gruppo per la Difesa del Litorale – Cavallino, Gruppo Salvaguardia Ambiente "La Salsola".

We present this appeal about the grave risk facing Venice and its Lagoon to the leaders gathered here in Venice on the 30'` anniversary of UNESCO's World Heritage Convention.

Italian special laws protect this World Heritage Site, comprised of Venice jointly with its Lagoon.

Over nearly 20 years, however, the capacity of the Italian State to manage and protect Venice and its Lagoon has been steadily weakened. Since 1984, the Italian government has delegated all state actions - from studies and research to project design and construction - to a single, exclusive, private concessionaire, the Consorzio Venezia Nuova. Thus far, this Consortium has received 2.5 billion Euros of public money for such works. The Consortium has proposed a colossal system, commonly called "MoSE": three mobile dams across the Lagoon's three outlets to the sea to counter high-water flooding in Venice.

Italy's National Environmental Impact Assessment Commission, whose review was required under law, gave the dams a negative judgement. The entire project is unsustainable and obsolete:

• Both its construction and maintenance would have heavy and permanent impacts on the Lagoon.

• It is neither experimental, nor gradual, nor reversible - key requirements under Italy's special' laws for Venice - and thus does not respect the precautionary principle.

• The project is not able to respond to fast-rising high waters (unless there are frequent "false closures" - i.e., the mobiles dams are often shut for false alarms).

• The project will not defend Venice from flooding in the event of worst-case scenarios for sealevel rise caused by global climate change.

The "MoSE" is presented as a project that will "save" the city from high water flooding, a message broadcast at international level with expensive public relations. The Italian government appears ready to build this obsolete design, whose negative impacts have been increased by the recent addition of "complementary structures", including shipping locks. The national government, in its 2003 budget, proposes 600 million Euros for the first phase of the "MoSE" project, but earmarked nothing for other essential protection measures in Venice - such as the architectural restoration of the city, pollution control and environmental re-equilibrium of the Lagoon, and alternative measures to reduce flooding.

In September of this year, the Venice City Council and the Venice Provincial Council both voted a negative assessment on the initial, "complementary structures" of the MoSE, specifically the shipping locks. Both Councils called for the design and construction of alternative works, independent of the "MoSE", to increase effectively the "dissipative capacity" of the Lagoon's three outlets and thus to reduce high tide peaks.

Indeed, effective and sustainable alternatives exist to defend the city now from most flooding and help return the Lagoon to environmental equilibrium. Among actions to be taken immediately:

1. Reducing the depth, width and wind exposure of the Lagoon's three outlets to the sea. By eliminating the majority of flooding events. These measures can be compatible with current port traffic, and they would be experimental, gradual and reversible.

2 Complete work to raise the lowest parts of the city. Venice lies between +80 and +200 cm above the mean sea lever mark. The Venice City Administration is now systematically raising low points of the city as it undertakes urban maintenance.

Protecting St. Mark's Square, the lowest part of the city and thus the most exposed to flooding, is slightly more complicated. Now at last, the separate work to raise the borders of the St. Mark's area will begin.

By raising and protecting low areas to +110 cm above the mean sea level mark, high-water flooding events would occur an average of less than 4 times a year, in most cases for only a small part of the city. Raising and protecting them to +120 cm will cut flooding to an average of only 1.5 times a year, for a total duration of little more than 2 hours a year.

Together, these two types of actions would reduce current flooding events to an average of only once every five years.

3 Removing oil tanker traffic from the Lagoon - as specified under Italy's 1973 special law for Venice - and building a dock along the Lido, outside the Lagoon, for the largest cruise ships that visit Venice would allow a further reduction in the depth of outlets and of shipping channels, eliminate additional flooding events, and help restore the Lagoon's environmental equilibrium.

Other vital actions are needed to protect this World Heritage Site: the Lagoon's morphology and its hydrodynamics need to be restored, water pollution in the Lagoon and its water basin should be reduced, and the production and movement of dangerous goods in the Lagoon should be stopped.

Once all these actions are taken to protect the city and its Lagoon, together with the sea defense system already built along the Lagoon's outer coast, an effective, environmentally compatible, and affordable system to protect Venice will be in place. Following- this, an appropriate project to protect against sea-level rise could be realized.

Venice jointly with its Lagoon is a unique part of the world's common heritage. They deserve the most sustainable strategies for protection and restoration.

Comitato "Salvare Venezia con la Laguna"

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