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August 28, 2000
Volume 78, Number 35
CENEAR 78 35 pp.23-31
ISSN 0009-2347
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Scientific research is a key factor in efforts to save Venice and its lagoon from pollution and rising waters
Photos by Michael Freemantle
Michael Freemantle
C&EN London
he historic Italian city of Venice is without question one of the most splendid cities in the world. Palaces, churches, and other historic buildings rise majestically from the water along the Grand Canal that snakes through the heart of the city. The first-time visitor is inevitably stunned by the magnificence and beauty.

No wonder the city attracts visitors by the millions each year. Some arrive by water bus or water taxi across the lagoon in which the city is located. Others reach the city by crossing the 4-km road and rail causeway that links historic Venice to the industrial part of the city on the mainland, the suburbs of Marghera and Mestre.

Once inside the historic city, there are no roads or cars. The ubiquitous water buses provide the principal means of transport. Or, if you feel energetic, you can amble through the maze of alleyways that link the 118 small islands on which the city is built. Some 400 footbridges cross the 100 or so canals that separate the islands. In the summer months, the more popular routes along these alleyways and over these bridges are so thronged with tourists that pedestrian traffic is brought to a halt. Venice both thrives on and suffocates from tourism.

If you tear your eyes away from the impressive sights as you walk around the city, you will soon see empty buildings that are in an advanced stage of decay, especially off the beaten tourist track. The deterioration results from the city's unique relationship to water and the difficulties and cost of maintenance and restoration of these buildings.

The decay is one of the major manifestations of what the New Venice Consortium (Consorzio Venezia Nuova) calls the "Venice problem." The consortium is a group of national and regional construction companies entrusted by the Italian Ministry of Public Works and the Venice Water Authority to implement measures under a law that aims at safeguarding Venice and the lagoon. As part of its work, it consults with leading national and international scientific institutes.

Multilayered problems

The problems of Venice and its lagoon are characterized by a high level of environmental and scientific complexity, the consortium notes on its website ( ). The consortium explains that high waters and tides, erosion and pollution, and physical and socioeconomic deterioration all represent elements of risk and danger that, although distinct, are closely interconnected and intricately bound together.

According to Pierpaolo Campostrini, director of the Venice-based Lagoon Research Consortium (Consorzio Ricerche Laguna), many research projects have been carried out on the Venice Lagoon over the past three decades. "The lagoon is one of the most studied environments in the Mediterranean," he tells C&EN. "Yet, in spite of all these projects, research is still needed to gain a deeper knowledge of some key aspects of the lagoon."

The Venice problem is also characterized by institutional and legislative complexity. Venice is the capital of the Veneto Region in northern Italy and of Venezia Province, one of the region's seven provinces. National ministries and regional, provincial, and local authorities, as well as the Venice City Council, are all responsible for various aspects of the administration of the city of Venice, its lagoon, and the surrounding areas. For example, the land that drains into the Venice Lagoon, an area of almost 1,900 km2, is administered by 100 local authorities.

Special laws dating back to 1973 assign specific responsibilities to various authorities concerned with safeguarding Venice and the lagoon. The Italian State has responsibility for the physical safeguarding and restoration of the hydrogeological balance in the lagoon. The Veneto Region is responsible for the abatement of pollution, especially from the drainage basin. And the city councils of Venice and the town of Chioggia at the southern end of the lagoon are responsible for urban conservation and maintenance and activities aimed at promoting socioeconomic development.

The Venice Water Authority (Magistrato alle Acque), which was founded in 1501, has responsibility under the Italian Ministry of Public Works for ensuring the survival of Venice, its lagoon, and the living species that inhabit it, and for protecting the lagoon from both natural and anthropogenic events.

The lagoon, which is the largest in Italy, is a wetland coastal area that consists of seawater, mud flats, salt marshes, fish farms, islands, reclaimed areas of dry land, sand banks, and a coastal strip between the lagoon and the Adriatic Sea. The lagoon has a mean water depth of 1.2 m and a surface area of about 550 km2, of which just over 400 km2 is open to the tides of the Adriatic Sea.

"The lagoon ecosystem consists of three parts that are closely connected to each other through reciprocal water exchanges," explains Gabriele Capodaglio, professor of environmental analytical chemistry at University Ca' Foscari of Venice. "One part is the mainland drainage basin that conveys freshwater to the lagoon. Another part is the lagoon itself. And finally, the tides of the Adriatic Sea influence the lagoon with the ebb and flow of seawater through three inlets in the coastal strip on the periphery of the lagoon."

One other significant factor in the lagoon's complex environmental equation is Porto Marghera, a port and petrochemical complex that lies on the northwest side of the lagoon. The district is one of the main centers of the Italian chemical industry. Ethylene, propylene, ammonium sulfate, caprolactam, chlorine, sodium hydroxide, and a range of other basic and intermediate chemicals are produced there and transported by pipe and road to various destinations in Italy and Europe and by sea throughout the world.

"There are about 1,000 companies in Porto Marghera, in all industries, with some 15,000 employees," notes Nelson Persello, vice director of the Association of Manufacturers of Venice Province. "Chemicals is the second largest sector, after petroleum," he adds.

Capodaglio (left), Campostrini, and Zago in front of the Accademia Bridge on the Grand Canal.

Much of the growth in the industrial zone took place in the 1950s to the 1970s, most noticeably with the development of chemical plants, steel works, and an oil refinery. "There was virtually no legal regulation of this expansion, and the plants discharged part of their industrial wastes directly into the lagoon and partly into uncontrolled dumps," the New Venice Consortium notes.

In the 1960s, to accommodate further industrial expansion, artificial islands were constructed on salt marshes south of the port. The islands were made from the materials that were dredged from the lagoon to create a channel for oil tankers between one of the Adriatic Sea inlets and the port. The reclaimed islands, which have a total surface area of more than 11 km2, drastically reduced the quantity and quality of water exchanged between the lagoon and the water behind the reclaimed areas. The expected industrial expansion on the islands did not occur, however.

Crisis factors

The New Venice Consortium identifies three crisis factors that endanger Venice and the lagoon: morphological deterioration, urban fragility, and environmental deterioration and pollution of the water.

The Palazzo Franchetti is home to the Venice Institute of Science, Letters & Arts.
Morphological deterioration means that the lagoon is giving way to the sea. Sediments, salt marshes, sand banks, and mud flats are disappearing. Land reclamation, digging channels for tankers, and other forms of human intervention have all contributed to this erosion. The deterioration has serious consequences, not only for the lagoon ecosystem but also for the historic city of Venice.

The pumping of water from the coastal aquifer during the period of rapid industrial growth in Porto Marghera is a notable example.

"Until the mid '70s, about 300,000 metric tons of groundwater per day were withdrawn for industrial and agricultural purposes," notes Pietro Tundo, professor of organic chemistry in the department of environmental sciences at the University Ca' Foscari. "The removal of this groundwater caused the whole city to collapse by 23 cm in relation to sea level" from the 1950s to the '70s.

Groundwater extraction is now strictly limited, and subsidence of the city has now returned to its natural rate of about 1 mm per year. However, the sea level in the lagoon continues to rise because of the increased exchange of water between the sea and the lagoon and rising sea levels attributed to global warming by some experts. The increasingly frequent high water levels and flooding are causing a number of problems. When tides are very high, for example, motor boats find it difficult to navigate under the city's many bridges and the movement of pedestrians is impeded by flooded walkways.

Urban fragility

High water levels are also damaging the city's fragile architectural heritage. Materials such as wood and reed used to construct many historic buildings in the city are particularly vulnerable to water. And there is another problem as well. It is salt rise, or "risalita salina" as the Italians call it. Rising damp in brick masonry results in salt crystallization in the brick pores and damage to the bricks.

Tundo directs the Venice-based Interuniversity Consortium on Chemistry for the Environment.
The basements of many of the historic buildings in Venice are constructed from Istrian stone, a compact limestone with a very low porosity that is therefore impervious to seawater, Campostrini points out. "This special stone was imported from Istria in Croatia," he says. "As it was expensive and very heavy to be carried such a long way, it was only used for the basements in buildings."

Over recent decades, however, seawater has often risen above the basements and penetrated other types of materials used to construct buildings.

"Many efforts have been made to reduce the influence of rising damp, such as the use of mechanical or chemical damp-proofing, and a lot of experiments have also been carried out to remove salts from brick-wall masonry or marble structures," notes Vasco Fassina, director of scientific research in the Superintendency to Artistic & Historical Property of the Veneto Region and scientific consultant of the Veneto Institute for Cultural Heritage. Both organizations are based in Venice.

Fassina and coworkers have carried out a number of studies on water damage to historic buildings in Venice. They include a study of salt efflorescence on the marble slabs used to construct San Maria dei Miracoli Church between 1481 and 1488.

"The study showed that the concentration of the more soluble chlorides and nitrates increases with height because of rising damp, whereas the less soluble sulfates are concentrated and enriched in the lower part of the building," Fassina notes. Damp-proofing inserted "at the foot of the brickwork prevented further saltwater reaching the upper brickwork and stopped the increase in the concentration of soluble salts. However, these salts have continued their aggressive action on the marble. Desalination of the brickwork and stones is therefore necessary for conservation." Fassina's group has also investigated water infiltration in the crypt of St. Mark's Basilica in Venice and the brick decay resulting from salt crystallization. The crypt walls are below average sea level and are completely saturated with salt water.

As the first step in a long-term program of restoration work, the group carried out on-site desalination experiments and showed that impregnation of the brickwork with consolidating materials containing ethyl silicate and siloxane-based polymers provides the best method of protecting the brickwork.

Past atmospheric pollution in the region of Venice also continues to cause building decay in Venice, according to Fassina.

"Venice's architectural heritage is in peril mainly because of past periods of atmospheric pollution that resulted in the accumulation of unstable compounds on the surfaces of buildings," he tells C&EN. "The rapid increase in the industrialization and urbanization which took place in Marghera and Mestre starting at the beginning of the 1950s sharply increased the concentration of atmospheric pollutants, particularly sulfur dioxide."

Scenes from Porto Marghera
As a result of this pollution, centuries-old stonework started to deteriorate rapidly. During the 1980s, emission of atmospheric pollutants decreased as methane gradually replaced oil as a fuel for heating systems in the region and with the reduction of emissions from the industries in Porto Marghera.

"However, although SO2 pollution decreased during the 1980s, the rate of stone decay has not decreased," Fassina notes. "We call this phenomenon the memory effect, because the state of conservation of a building material is influenced by the cumulative exposure of materials to the environment during the life of the building."

The decay of Venetian buildings made of limestone, as with the decay of many other limestone structures throughout the world, largely results from the transformation of limestone's principal constituent, calcite (CaCO3), to gypsum (CaSO4·2H2O). Fassina's group has observed two types of deterioration in the limestone used to construct buildings in the city.

"In Istrian stone, gypsum formation only affects the surface of the stone," he notes. "After removal of black scabs of gypsum, the stone appears to be in a good state, probably because of its low porosity."

The decay of marble, another construction material commonly used in Venice, is not superficial, however. "Rainwater penetrates inside the marble, producing a mixture of the original calcite, gypsum, carbonaceous particles, and natural or man-made atmospheric dust," Fassina points out. "The amount of damage to the marble depends on the geometry of the monument and the degree of exposure to or shelter from rainwater."

Water pollution

The third crisis factor that is putting Venice and the lagoon at risk is water pollution.

"There are three main streams of effluent entering the lagoon," explains Giorgio Modena, a chemistry professor at the nearby University of Padua who recently chaired a scientific research program on Venice and its lagoon. "These are the effluent from the city itself, effluent from agriculture, and effluent from industry."

The discharge of municipal waste into the canals and the lagoon is as old as the city itself. The city does not have a sewage system.

"Most domestic apartments and houses discharge sewage directly into the canals without treatment, apart from mechanical recovery of solids by gravity in a sedimentation tank," explains Maurizio Selva, assistant professor of chemistry at University Ca' Foscari, who lives in an apartment in the city.

He points out, however, that all commercial enterprises in the city--for example, hotels, restaurants, bars, and shops--are now required by law to treat sewage biologically.

Tundo remarks that the discharge of municipal sewage into the lagoon is not a significant problem compared with the problems created by agricultural and industrial effluents.

"The lagoon itself is very good at degrading the domestic organic waste from the city," he says.

The lagoon, however, is not only the drainage basin for the city of Venice and populated islands in the lagoon such as Murano and Burano, but also the drainage basin for parts of the Province of Venice and the neighboring provinces of Padua and Treviso. Much of this area is devoted to farming.

Numerous rivers flow into the lagoon, bringing in not only water and sediments but also pesticides and phosphate and nitrate nutrients. An estimated 7,000 metric tons of nitrates are released into the lagoon each year, of which 53% comes from agriculture and livestock and 31% is from civil sources such as houses, offices, and schools. Farming and civil sources, respectively, account for 46% and 39% of the 800 metric tons of phosphates that enter the lagoon each year. "These nutrients increase the biological activity of the lagoon," Tundo notes.

As a result, some algal and animal species that are more resistant to pollution and eutrophic conditions in the lagoon have benefited at the expense of other species. Most notorious are the macroalgae known as Ulva rigida. They proliferated at certain times of the year during the latter half of the past century, depriving the water of oxygen and thereby suffocating many other forms of life in the lagoon. And they blocked the light required by flora and fauna on the lagoon bed. When the macroalgae died and putrefied, they released hydrogen sulfide, causing unpleasant smells throughout Venice.

The problem was particularly acute in the 1980s. One study in 1987 reported up to 2 kg dry weight of macroalgae per square meter of lagoon at the seasonal peak in May and June and estimated that the entire lagoon contained a minimum of 300,000 metric tons dry weight of the macroalgae [Estuaries, 15, 517 (1992)].

"The great amount of algae in the sediment prevented hydrodynamic movement of the water," explains biologist Cristina Zago, who has carried out research on the topic. Zago is currently a researcher at the Lagoon Research Consortium, known as Corila, working on the consortium's environmental chemistry program. "We therefore had a problem with anoxia in the water and the sediment."

One species of insect that prospered as a result was the chironomid mosquito. "Chironomid larvae live very well in anoxic sediments," Zago explains.

So well, in fact, that in some years during the 1980s, dense clouds of the mosquitos swarmed into the city and the nearby airport, causing havoc.

"All the walls of the buildings in Venice were covered with these mosquitos, and on some days the airport was closed," she tells C&EN.

Zago reports that the density of macroalgae in the Venice Lagoon greatly decreased during the 1990s [Estuarine, Coastal Shelf Sci., 48, 155 (1999)]. "The reason for this macroalgae depletion in the lagoon is still unknown," she notes.

She observes, however, that possible causes could be the mechanical removal of biomass from the lagoon by harvesting machines during peak growth periods and also the construction of a central sewage treatment plant that came into operation at Porto Marghera in the late 1980s.

Water provides the principal means of transport--for goods as well as people--around the city.
Professor of applied ecology Adriano Sfriso, professor of environmental chemistry Bruno Pavoni, and their coworkers at University Ca' Foscari have conducted a number of studies of nutrient concentrations in the Venice Lagoon over recent decades. They have shown that nitrogen concentrations have been decreasing since the 1970s. In particular, surface sediment nitrogen concentrations began to decrease in the 1980s as a consequence of reduced industrial activities in Porto Marghera.

Sfriso and Pavoni also point out that phosphorus concentrations in the lagoon have decreased significantly since the 1980s, following a legal requirement for the progressive reduction of the element in commercial detergents.

The discharge of industrial waste into the lagoon has declined markedly since the 1980s--especially with the introduction of tough, legally enforced environmental regulations. The New Venice Consortium notes that nowadays 80% of the industrial waste from Marghera and Mestre is treated in purification plants.

The situation with regard to agricultural effluent is more problematic, however. "The law sets strict limits on the amounts of materials and pollutants that can be discharged into the lagoon," Campostrini tells C&EN. "However, because water drains from land around Venice in numerous small channels, it is difficult to monitor and control the discharge of agricultural pollutants."

And in any case, data about this source of pollution are scarce. "The Magistrato alle Acque (Venice Water Authority) has funded a big research project, called Drain, to determine the loads of pollutants carried into the lagoon by the nine main rivers that flow into it," Tundo notes. The project is being carried out by scientists of Italy's National Research Council (CNR); the Universities of Ca' Foscari, Padua, and Bologna; and the Venice-based Interuniversity Consortium on Chemistry for the Environment (INCA) .

The lagoon also continues to suffer from a legacy of persistent nonbiodegradable organic and inorganic pollutants in the lagoon sediments around the port that resulted from industrial activity in Porto Marghera in the 1950s to 1970s. The pollutants include dioxins; polychlorinated biphenyls; and heavy metals such as mercury, nickel, cadmium, chromium, and lead. In addition, relatively small amounts of heavy-metal pollutants originated from the glass factories on the island of Murano.

According to the New Venice Consortium, there are 17 abandoned dumps in the lagoon that contain a total of about 5 million m3 of pollutant materials. The consortium notes that between 1930 and 1996, pollution resulted in a 60% decrease in water transparency in the lagoon; a 50% and 20% decline in the number of plant and bird species, respectively; and an 80% reduction of the amount of the marine eelgrass that consolidates the bed of the lagoon.

"Even though the water is not polluted by the discharge of industrial waste nowadays, the sediments still retain heavy metals and nonbiodegradable chlorinated aromatic compounds," Tundo observes.

Stefano Raccanelli, head of the INCA laboratory for the analysis of dioxins and related compounds, and coworkers have been monitoring dioxin levels in the lagoon over recent years. The term "dioxin" refers to a group of 210 congeners of polychlorodibenzodioxins and polychlorodibenzofurans that are toxic and highly persistent in the environment, Raccanelli points out.

Tourists attractions include Plazza San Marco and the canals (below).

Dioxins are widely distributed in the lagoon and the city's canals, according to Raccanelli. Low concentrations have even been found in the Adriatic Sea, 15 km from the Venice Lagoon.

"It is obvious from various studies since the early 1990s that the industrial area of Porto Marghera is the main source of pollution," he remarks. "One study also showed that Venice downtown channels are contaminated with a mix of dioxins from urban sources such as an urban waste incinerator that operated until 1983, boat-engine emissions, and general diffusion due to sediment resuspension. The movement of sediment is caused by motorboat traffic and dredging and naturally by winds and tides."

Dioxins penetrate the human food chain, although, according to Raccanelli, preliminary results using mussels as indicators show that the average level of contamination in these mollusks is comparable with that in other parts of the world.

A particular problem, however, is illegal fishing. "Even though the mayor of Venice has forbidden fishing in areas characterized by high levels of contamination, mollusks have been extracted illegally from such areas in recent years," Raccanelli notes.

Life in the Venice Lagoon also has to contend with another source of pollution: the atmosphere. "Venice is on the main route for traffic between Italy, Austria, Hungary, and other European countries," Tundo explains. "There is a lot of heavy traffic, particularly trucks, and therefore a lot of atmospheric pollution. Because of prevailing winds, polycyclic aromatic hydrocarbons and heavy metals such as lead from the gasoline eventually end up in the lagoon."

He notes that the Venice Water Authority has recently funded a research project to estimate the loads of pollutants in the lagoon due to atmospheric depositions and to determine the fate and the spatial distributions of the contaminants in the environment. The project is being carried out by the same research groups that are involved in the Drain project.

Capodaglio is particularly interested in the mechanism of transport of pollutants from the land to the sea. "We are just beginning a new research project on the impact of aerosol transport on pollution in the lagoon," he tells C&EN. "At the moment, we do not know exactly to what extent pollution in the lagoon derives from hydrosol transport from the land."

Protective measures

In 1992, a general plan backed by law to implement measures designed to safeguard Venice was launched by the Venice Water Authority and the New Venice Consortium. The plan is two-pronged.

The first prong relates to the protection of the city from high water levels and flood damage by improving its physical defenses by, for example, raising embankments, and also by reinforcing the coastline to protect it from storm damage.

One of the most contentious measures was a plan to build mobile flap-gates to protect the lagoon from high tides. The flap-gates were designed to rest horizontally on the bottoms of the three inlets to the lagoon during normal tide conditions. When high tides were forecast, compressed air would be used to raise the flaps in order to isolate the lagoon from the sea.

"The design, known as MOSE, was completed in 1992 after 20 years of debates and discussions, approved in 1994, and submitted for environmental impact evaluation in 1995," Tundo points out. "An international council of five experts was appointed in 1996 to evaluate the environmental, economic, hydraulic, and technological aspects of the project. The experts were positive about the project, but even so, MOSE was rejected by the Ministry of Environment in December 1998. The ministry claimed that the gates would have a potentially adverse impact on the lagoon's environment."

Raccanelli monitors dioxin levels in the lagoon.
Last month, the ministry's decision on the environmental impact assessment of the MOSE project was declared null by an Italian court. "It is still not clear if this means that a new assessment is needed or if the project is licensed to go ahead," Campostrini explains. "In all probability, the matter will go to a higher court, although it is unlikely that it will have the final word, because the problem is political. A few weeks ago, a special ministerial committee for safeguarding Venice, which includes the mayors of Venice and Chioggia and representatives of the Region of Veneto, met and decided that, due to the existing conflict between the ministries of the environment and public works, a decision should be made by the Italian government as a whole. As a result, most observers agree that a decision will now have to wait until the results of the general elections in spring 2001."

The second prong of the general plan aims at improving the environmental quality of the lagoon through a series of interventions that tackle the factors that have caused the deterioration of the lagoon's ecosystem and that also reconstruct and maintain the natural environment of the lagoon.

A morphological restoration program, for example, includes planting marine eelgrass on the bed of the lagoon; restoring minor islands in the lagoon; and converting the artificial islands that were constructed in the 1960s back into wetlands with salt marshes, mud flats, and channels that allow better water exchange.

Other parts of the environmental improvement program include harvesting macroalgae, constructing septic tanks in the city of Venice, and developing phytopurification systems in the river estuaries. These systems contain aquatic plants and other biological organisms that consume the large amounts of nitrates and phosphates in the freshwater that flows into the lagoon. One phytopurification pilot project is already underway, and another is in the planning phase.

The program also aims to reduce pollutant loads in the lagoon by either removing abandoned dumps of pollutants or isolating them from the lagoon by building embankments around them and sealing them with waterproofing materials. In addition, a number of feasibility studies have been carried out on the possibility of eliminating crude oil traffic from the lagoon by, for example, diverting the traffic to other ports in the Adriatic Sea.

Many buildings in Venice are in an advanced state of decay.
"Preserving the lagoon from further degradation and taking measures to restore its integrity while maintaining the chemical industry and the current level of employment in Porto Marghera is a major challenge for the future," Tundo comments.

Industry cooperation

On Oct. 21, 1998, the Italian ministries of the environment, of industry, and of public works; labor unions; local authorities; and chemical companies launched a program of environmental improvement and sustainable development for Porto Marghera.

The agreement, which was signed in Rome, commits Porto Marghera's chemical companies to spend around $800 million over the next few years on a variety of projects. EniChem, Italy's largest chemical company, will contribute about 70% of the total amount.

"The program is ambitious," Tundo says. "It aims to establish and maintain the optimum conditions for the coexistence of industrial development and environmental protection in Porto Marghera. The agreement identifies a number of specific objectives, including the reduction of air and lagoon pollution, remediation and/or isolation of contaminated sites, and improved handling and storage of dangerous materials."

The first part of the project, which started as soon as the agreement was signed, targets the northern section of the industrial complex, which lies close to the residential districts of Marghera and Mestre. The aim is to create a buffer zone between the residential area and industrial activities by demolishing an old petrochemical plant in the zone. This process is not simple because the plant contains asbestos. As part of the project, contaminated soil and subsoil in the zone is also being remediated.

Under the agreement, companies must not discharge polluting materials into the lagoon and they must also clean all the water that comes into direct contact with chemical plants and processes. This water then has to be sent for further purification to a public treatment plant in Fusina, which is located on the southern part of the lagoon.

Much of the $800 million investment will be devoted to the development of advanced chemical technologies. EniChem, for example, plans to replace its mercury-cathode-cell technology with membrane-cell technology in its chlor-alkali plant. The company currently manufactures around 190,000 metric tons of chlorine and over 200,000 metric tons of sodium hydroxide each year.

The company will also reduce its phosgene capacity from 30 metric tons to less than 15 metric tons and use bunkering tanks for storing the material. It has also initiated a research program to develop technology for replacing phosgene with dimethyl carbonate [(CH3O)2CO] in the production of toluene diisocyanate (TDI), a starting material for the manufacture of polyurethane. EniChem currently produces almost 120,000 metric tons of TDI annually in its Porto Marghera TDI plant--the only TDI plant in Southern Europe.

Memoll and selva: developing green reagents
According to EniChem Chairman and Chief Executive Officer Fabrizio d'Adda, the decision made 60 to 70 years ago to build a petrochemical complex in Venice was somewhat crazy. "But we have to accept the value of it now," he remarks. "We must reason more pragmatically and less hysterically for sustainability in Porto Marghera. Social acceptance is crucial for the survival of the chemical industry in Europe. But at the end of the day, we must generate cash and profits for our shareholders. We therefore need an acceptable compromise between environmental sustainability and the ability of industry to compete."

Research consortia

A number of scientific research institutions and consortia based in Venice are engaged in a variety of programs directed at monitoring and improving the environmental quality of Venice and its lagoon.

INCA is one such consortium. It has its headquarters and three laboratories in a science park in the reclaimed northern section of Porto Marghera. The park is called Venice Gateway for Science & Technology, or VEGA for short.

"The INCA consortium was founded in October 1993 and relies on the research contributions of chemists from about 30 Italian universities, including University Ca' Foscari," INCA's director, Tundo, explains. "The chemists have various fields of expertise, for example, in environmental, physical, organic, inorganic, analytical, and industrial chemistry. The objectives of the consortium include establishing laboratories for advanced research and coordinating and developing environmental science research projects for both public and private corporations.

"At the present time, INCA's research activities are mainly centered on the prevention of chemical pollution through the development of new reactions of industrial interest based on the application of clean technologies and the recovery of energy and matter," he continues. "The consortium is also active in the characterization of chemical pollutants in water, soil, and the atmosphere."

The research is carried out in consortium labs throughout Italy. INCA's laboratories in VEGA are devoted to analysis of dioxins, biodegradation research, and "green" chemistry.

Earlier this year, INCA started a two-year research program on green sustainable chemistry financed by the Italian government. "We won funding totaling $4 million for six projects, one of which is the development of infrastructure and five are research projects," Tundo explains.

The program includes the development of INCA's green chemistry laboratory, which is headed by Sofia Memoli. One of her particular interests, which she is working on with Tundo and Selva, is the development of dimethylcarbonate (DMC) as a green reagent.

"DMC is a nontoxic, environmentally safe reagent that can be used in organic synthesis as a green substitute for toxic intermediates such as phosgene in carbonylation reactions, and dimethylsulfate and methyl chloride in methylation reactions," Memoli explains. "Other industrial applications include its use as a solvent for removing asphalt and metals from the residue of crude oil distillation, as a lubricant, as a component of oxygenated gasoline, and as an expanding system for polyurethane foams."

Whereas INCA's research activities aim to develop environmental chemistry in Italy as a whole, not just Venice, the research consortium known as Corila focuses specifically on the lagoon.

The consortium, which was founded last year and has its headquarters in the beautiful 15th-century Palazzo Franchetti on the Grand Canal in Venice, has funding of $6 million from the Italian government to promote and coordinate research activities on the Venice Lagoon over the next five years.

"The research will embrace not just environmental science but also architecture and economics," Corila's director, Campostrini, explains. "We have recently published a call for proposals from research groups."

"Research in the environmental area will be wide ranging," he continues. "This part of the program will aim to study and evaluate the quantity and quality of water exchanges between the sea and the lagoon."

Other projects will examine the hydrodynamics and morphology of the lagoon, chemical pollution, the biodiversity and quality of the lagoon ecosystem, the efficiency of the lagoon metabolism, loading from the drainage basin, and the influence of global climate change. In addition, there are plans to develop and validate mathematical models, principally using the data collected in these research projects, to study the lagoon in all its complexity.

"The Corila research program will also focus on the sustainable economic development of the Venice Lagoon area," Campostrini says. At present, apart from the industrial economic activity in Porto Marghera, the main economic resources of Venice and the lagoon are tourism and fishing.

The relationship between historic Venice and the lagoon is both its strength and weakness, Modena remarks. The city attracts numerous tourists, but it is becoming less attractive as a place to live for the local population or as a place for businesses to set up offices. One of the main problems is the difficult access to buildings in the city, many of the which can only be reached along narrow alleyways.

"The center of gravity of Venice's urban population has moved inland in recent decades," Modena observes. "Relatively few local people want to live in the city."

Tundo suggests that Venice and its lagoon deserve international attention. "It is a very special natural environment with a wonderful and unique city which needs, for its survival, to be strongly anchored to productive activity and not only to tourism," he says.

Campostrini is optimistic about the future of Venice. "With increasing environmental awareness and with the agreement program for Porto Marghera, the situation is clearly improving," he says. "We can now sometimes look out of the windows here at Palazzo Franchetti and see people fishing along the Grand Canal. A few years ago, there were no fish here. And some bird species that had disappeared are now returning to the lagoon. Venice and the lagoon are being revitalized.

"The lagoon system and its dynamics represent the perfect laboratory to develop an approach in which scientific, technological, and economic factors interact and influence each other," Campostrini concludes. "If we can find a solution here to our problems, then it might be possible to apply that solution elsewhere in the world."

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