Restore, Recycle and Renovate the Venetian Lagoon by Ana Laura González

Restore, Recycle and Renovate the Venetian Lagoon Control Risks by Man-made Territory Ana Laura González Sánchez Cristopher Tapia Bolados Keyu Zhu

Fall Semester 2019-2020

IUAV - Università Iuav di Venezia EMU – European Post-master in Urbanism analaura.gs00@gmail.com

IUAV-EMU 2019-2020 Design Studio Course instructors

Paola Viganò IUAV-EMU Programme Director

Alvise Pagnacco Ricardo Avella Ludovico Centis Irene Guida Mariano Andreani Giambattista Zaccariotto Sybrand Tjallingii

modalità e tempi per la richiesta di materiale grafico Università Iuav di Venezia servizio Comunicazione e immagine

Sea and lagoon bottom (m) Fig. 1 Bathymetric chart of the Venetian Lagoon by 1809-1811, made by the napoleonic captain Augusto Dénaix (Retrieved from: http://www.silvenezia. it/?q=node/56). Fig. 2 Bathymetric chart of the Venetian Lagoon 1932. (Retrieved from: http://www.silvenezia. it/?q=node/56).

land

0 ÷ -1

marshes (barene)

-1 ÷ -2

built

-2 ÷ -5

-5 ÷ -10

-10 ÷ -20

<-20

Restore, Recycle and Renovate the Venetian Lagoon

Introduction The struggle of the lagoon to recover its lost surface Over the centuries, the Venetian Lagoon has undergone constant morphological transformations; Beyond the natural transformations, the territory has become a project of the man who sought to control the risks that the rivers represented from the mainland and on the other side the Adriatic Sea, all to preserve the military and commercial advantages they had. As a result, the rivers were diverted to avoid sedimentation, canals and dikes were built to prevent flooding, 8,865 ha. of the water surface were closed for the creation of fishing valleys, almost 7,000 hectares of land have dried up since the beginning of the 20th century. Marshes, turning them into mainland for new uses such as the port, industrial areas and the airport and after the arrival of steam, the mouths of the lagoon and the canals of the port were intervened (Malamocco 1840-1845, Lido 1882-1910, Chioggia 1910-1934) to facilitate access and navigation of larger tonnage ships. Although these interventions have helped in the preservation of Venice, it is these same interventions that put Venice at risk since they have caused the lagoon to undergo significant ecological modifications, generating sediment loss and drastic reduction of its original characterized forms for its shallow brackish waters (velme) and an ecosystem rich in marshes (barene) that favor the exchange of water and species. With this, the lagoon becomes more vulnerable to the effects of climate change, a global problem, with negative environmental, political, economic and social implications; Therefore, this work aims to expose some of the risks, challenges and opportunities that the Venetian Lagoon is facing. In order to adapt to the uncertainty of climate change.

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Fig. 3 barane decrease over the years according to D’Alpaos. (Sourse: made by Francesco Lombardi, with data from D’Alpaos, L. (2010). L’evoluzione morfologica della Laguna di Venezia attraverso la lettura di alcune mappe storiche e delle sue carte idrografiche.)

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Risks, Challenges, & Opportunities in Lagoon 1 Risks in Lagoon 1.1 Marshes decrease Marshes are considered an important ecosystems on Earth. This fact is a result of their ecosystem functions and services they provide. Their recently accelerated rate of loss is much higher than any other ecosystem on the planet. The causes of marshes habitat decline could be linked to agriculture, urban development, industrial use, dredging, and mariculture in relation to accelerated sea-level rise by its risk of submergence (Ivajnšič, et-al. 2018). The loss of barene, beyond its ecological function, such as CO2 stackers, water quality improver by filtering runoff and by metabolizing excess nutrients, and functioning as nursery area for fishes,crustacea and insects, causes the lagoon to deepen.There the importance of taking care of them since they protect from erosion by buffering waves and trapping sediments and reduce flooding by slowing and absorving rainwater and seawater.

40 km2 of marshes in 2003

64 km2 of marshes in 1970

105 km2 of marshes in 1932

158 km2 of marshes in 1901

254 km2 of marshes in 1556

Restore, Recycle and Renovate the Venetian Lagoon

Fig. 5 Salt marsh photo (Sourse: taken by the authors)

Fig. 4 Salt marsh trancset and description of the habitat types, according their elevation. Grey line represents the mean excursion of neap tide (35cm); hight tide could reach 100cm and extraordinary tide more than 130 cm. (Sourse: Ivajnšič, et-al. The fate of coastal habitats in the Venice Lagoon from the sea level rise perspective, 2018)

1.2 Marsh habitats, accretion rate and submerge risk According to the study “The fate of coastal habitats in the Venice Lagoon from the sea level rise perspective” there are seventeen different plant communities in the Venice lagoon according to their mean elevation ranging from 0.26m to 0.49m. The location of these also plays an important role in the development and conservation of different types of habitats since processes such as land subsidence and accretion rates are crucial to understand how climate change and with it, sea lever rise will affect these ecosystems. Accretion is the vertical growth of the marsh which occurs when organic and / or inorganic sediments are deposited onto the marsh during inundation [allochthonous growth], as well as when salt marsh plants grow and decompose [autochthonous growth] Significant differences in accretion speed between the northern and the southern parts of the Venice Lagoon salt marsh were found (FIG 5). The Venetian Lagoon was divided into two parts (N and S) where different accretion rates (N = 0.21 cm yr − 1 and S = 0.46 cm yr − 1) were considered. Which means that in natural conditions it would take 100 years for the marsh (barene) of the southern part of the lagoon to grow the 46 cm of sediments that it has lost, while it would take 220 years for the marsh (barene) of the northern part to reach the same amount of sediments. The above directly affects the risk of flooding of habitats, so by 2075, 37 to 48% or even 51% of the Venice lagoon coastal habitats could lie under water (FIG 8). This information (what, where and when) is of crucial importance to initiate enhance planning and management policies, and now that we know that nothern part of the lagoon presents more problems for its adaptation to climate change and sea level rise, it is necessary to prioritize it.

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Fig. 6 Significant differences in accretion speed between the northern and the southern parts of the Venice Lagoon salt marsh were found. The Venetian Lagoon was divided into two parts (N and S) where different accretion rates (N = 0.21 cm yr − 1 and S = 0.46 cm yr − 1) were considered. Which means that in natural conditions it would take 100 years for the marsh (barene) of the southern part of the lagoon to grow the 46 cm of sediments that it has lost, while it would take 220 years for the marsh (barene) of the northern part to reach the same amount of sediments. (sourse: made by the autors with information from (Ivajnšič, et-al. 2018).

Fig. 7 Graphic of accretion rate salt marshes in nothern and southern part of the venetin lagoon (sourse: made by the autors with information from (Ivajnšič, et-al. 2018).

Fig. 8 Scenarios 2025 - 2100 of salt marshes submerge risk in venetian lagoon. By 2075, 37% to 48% of the Venice lagoon coastal habitats could lie under water and by 2100 51%. Most of them in the northen part of the lagoon. (sourse: Ivajnšič, et-al. The fate of coastal habitats in the Venice Lagoon from the sea level rise perspective, 2018)

Restore, Recycle and Renovate the Venetian Lagoon

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1 Risks in Lagoon 1.2 Water Pollution

Fig. 9â&#x20AC;&#x201A; water pollution in Venice Lagoon. (sourse: made by the authors with information from http:// www.atlantedellalaguna.it/)

The improvement of the quality of the water and sediments of the lagoon is a crucial issue that must be addressed as a priority, since a long time ago, the Magistrate of the Waters has carried out some interventions for this purpose that try, in particular, to isolate the contaminants present in landfills, which were used in the past to eliminate waste of different origins, including slags from industrial productions and settlements discharges, but it has not been enough, so it is necessary to take actions that complement these works in order to improve the quality of water and sediments in the lagoon. According to the information found in the Atlante della laguna, it can be observed that the water quality worsens as it becomes more in contact with the port and the mainland and that in the northern part of the lagoon there is a regular quality, as it have contact with the fishing valleys. This is an interesting sign since fishing valleys can play a crucial role in improving the quality of water and sediments, since the water inside them is of better quality according to some interviews conducted with experts. It is necessary to design a strategy that reduces the polluting substances transported to the lagoon from the water courses that flow from the basin and look for transition zones between the mainland and the lagoon capable of filtering and absorbing the pollutants (phytodepuration)

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Fig. 10 fish markets of the Veneto region. According to the “Rapporto Statistico del Veneto 2018” it can be seen that there are six markets, all with sale of local products, but with two exceptions that integrate foreign products. We are talking about the Chioggia market; with more than 9 thousand tons of fish per year and with a mix of sales of imported products, but with mostly local products and the Venice market; with 1,295 tons / year but with products mostly imported from abroad. What can also be seen on the map is that the fish markets are located where there are fishing valleys, with the exception of the fishing valleys in the north and south of the Venice lagoon, which has caused the territory in these keep as natural as possible, so it could be said that they are somewhat safe from global exploitation, while retaining their environmental aspects, but with some other negative economic implications. (sourse: made by the authors with information from CTR and Raporto Statistico del Veneto 2018 )

Restore, Recycle and Renovate the Venetian Lagoon

Risks, Challenges, & Opportunities in Lagoon 2 Challenges 2.1 Fishing decreasing Fig. 11 At left. Commercial species found in Venice Lagoon and in fishing valleys (Sourse: made by the autors with information from Rosseto Luca, “The Management of Fishery in the Lagoon of Venice”, Padova, 2000. Fisherman interviews from september to november 2019. Cavallitno Treporti. Venice. Italy)

The Venice lagoon has been a commercial and economic power. Since medieval times, fishing and agriculture have played a very important role in making this happen. Lagoon of Venice plays a critical biological role. Not only are a place with an important source of fish but works also as nursery areas of many commercial fishes or feeding grounds for others. Therefore, lagoon environment allows many species to complete their biological cycle. However, the lagoon fishery economy is downsize its importance in the recent times. Several issues have arisen recently: - progressive subtraction of lagoon covered water areas because of sediment deposition; - competitive and conflicting uses of lagoon area: navigation, public facilities, tourism, industrial and residential settlements; - heavy pollution and environmental degradation coming from industrial and agricultural activities; - the increasing fishing effort beyond the sustainability level; - the adoption of sophisticated fishing capital-intensive technologies with a consequent decrease in manpower level and increase in efficiency. (Rosseto Luca. “The management of fishery in the Lagoon of Venice”) Mainly on the issue of production, some of the risk factors are related to climate change: extreme temperatures, disappearance of some species within the lagoon, migration of new bird species to the lagoon due to climate change. as an example, the flamingos that arrived just 15 years ago and that put the subsistence of the fish at risk as they eat the crustaceans inside the valleys, which serve as food for the fish, predation by the birds and human predation. Some other risk factors are related to the economic interests of the owners of the valleys, where mainly in the north, according to an interview conducted to Galdino Vienello (fisherman, farmer and owner for 30 years of “Agriturismo Le Manciane”), families with other profitable businesses acquire these lands for the only purpose of personal recreation such as sport hunting, so fish production will remain in second plane because the necessary investment is more, compared to the result that can be obtained from fishing. Some other risk factors are related to the competitiveness of the product in a global market: According to Stefania Lazzarini, an employee of the Ittica Center company, specializing in the purchase and distribution of fish for restaurants, located in Cavallino Treporti; there is no market in the north of the lagoon because there is not enough product to sell, besides that more specialized labor is scarce; and since the price depends on the quantity of the product, the prices are not competitive in the global market, reaching up to double those imported from Greece or Turkey.

Fig. 12 Production of main fish lagoon species (Sourse: made by the autors with information from Rosseto Luca, “The Management of Fishery in the Lagoon of Venice”, Padova, 2000)

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Fig. 13 Former proposal Park North Venice Lagoon. The map shows the territorial scope for the establishment of the Northern Lagoon Park of Venice, as identified by the Venice Territory Planning Plan approved by the Province of Venice on October 10, 2014. The regional environmental and anthropological park Local interest of the Northern Lagoon of Venice was subsequently repealed in April 2016. (Sourse: made by the autors with information from http://www.atlantedellalaguna.it/)

Former proposal Park North Venice Lagoon

Risks, Challenges, & Opportunities in Lagoon 3 Opportunities 3.1 Requalification of the territory The city of Venice approved in July 2003 the Institution of the “Parco della Laguna”, an instrumental organ of the Municipality whose task is the environmental and socioeconomic improvement of the North Lagoon area, through the definition and promotion of uses compatible with the safeguard of naturalistic, archaeological, historical and cultural sites values. The map shows the territorial scope for the establishment of the Northern Lagoon Park of Venice, as identified by the Venice Territory Planning Plan approved by the Province of Venice on October 10, 2014. The regional environmental and anthropological park Local interest of the Northern Lagoon of Venice was subsequently repealed in April 2016.

Fig. 14 Citizen concerns from the former proposal Park North Venice Lagoon. (Sourse: made by the autors with information from http://www. atlantedellalaguna.it/. Committee Risorse Vitali: http://vasvenezia.altervista.org/indexf622. html?option=com_content&view=article&id=327:let tera-ai-giornali-il-parco-che-vogliamo&catid=34:ilparco-della-laguna-di-venezia&Itemid=41)

The repeal came after various concerns of the citizens of the lagoon and its surroundings about the limitations that this new figure on the lagoon would represent to the detriment of the needs of those who live and work within it. However, this proposal leaves the door open for further negotiations among those involved in order to requalify the territory with a more sustainable and territorially more adaptable perspective to the real needs of the lagoon that go beyond the limits presented in orderto adapt to climate change.

Restore, Recycle and Renovate the Venetian Lagoon

3.2 Learning from Fishing Valleys The brackish water mirrors of 55 thousand hectares separated from the sea and with a great biodiversity, have been enriched with the passing of the years of knowledge of man about it exploitation. According to Galdino Vianello, fisherman, farmer and owner for 30 years of “Agriturismo Le Manciane” already before the 18th century, in the lagoon, there was an economy based on salt and the cultivation of vegetables, it was an open lagoon plan with barene and velme that favored the exchange of water and species with the ocean. Then, the lagoon harbored a dozen species of fish of commercial interest, as well as several crustaceans and edible molluscs. In words of the Canal de Pordelio’s fisherman, Alessandro Novello, who for more than 20 years has carried out this activity professionally; adult fish, or juvenile stage, enter the lagoon in the spring period, invoked by the temperature of the water. That because, as being less deep, heats up before the sea; and in autumn, due to the opposite effect, they return to the still warm waters of the Adriatic. During this summer stay, the fish have greater growth than the similar ones that remained in the sea, due to the abundance of food available in the lagoon. According to the historian Piero Santostefano, member of the cultural association “Tra Mar e Laguna”; At the end of the 18th century, with the fall of the Serenissima, a great transformation came in the lagoon, arising from the observation of man towards the seasonal migrations of fish and taking advantage of the uncertainty of the control of the territory between Napoleon and Austria. Between the years of 1700 and 1800 the delimitation of the most suitable places for the growth of young fish emerged, causing them to remain in the lagoon even in the fall and winter, to raise them and consume them later when they reached their commercial size (2 years). This meant the closure of 8,865 ha of the water surface, translated into fishing valleys, first with stick fences, which later became permanent structures such as dikes, creation of systems to protect the fish during the winter and mobile locks. On one hand they prevent the fish from leaving and on the other they regulate the exchange of water with the lagoon and in some cases with the freshwater channels to manage their environmental needs, since otherwise the valley, during the summer with evaporation it could reach an excessive salinity for the life of almost all species of fish, while in winter it could freeze and thereby lose the fish. As the fishing valley´s owners began to close the area of the valley with pipes, to improve the overall result of fish farming, it was necessary to plant young fish inside the valleys, since the natural scourge, almost completely avoided by the dikes, became insignificant. In addition, with the sowing of fish, it was possible to have a much higher density in the valley than the natural one in the lagoon and this made it possible to compensate for losses due to various factors, from bird predation, to adverse weather conditions, such as cold or heat excessive, so in the 19th century they became an efficient way of growing different species of fish.

Fig. 15 Fishing Valleys from above (Sourse: image taken by the authors)

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17 source: CTR

FISHING VALLEYS NAME

VALLE CONTARI NA VALLE DEGLI ORCOLI VALLE DEL CAVALLI NO VALLE DELL'AVERTO VALLE DI LI O MAGGI ORE VALLE DI SAN MI CEI VALLE DOGA' VALLE DRAGAI SOLO VALLE FI GHERI VALLE FOSSE VALLE GHEBO STORTO VALLE GRASSABO' VALLE LI ONA VALLE MOROSI NA VALLE OLI VARI VALLE PALEAZZA VALLE PERI NI VALLE PI ERI MPI E' VALLE SACCHETTA VALLE SACCHETTI NA VALLE SERRAGLI A VALLE ZAPPA VALLESI NA FALCONERA

Restore, Recycle and Renovate the Venetian Lagoon

20 Fishing Valleys DIVISION

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FISHING VALLEYS NAME

22 Fig. 16 Fishing Valleys in Venice Lagoon 8.865 ha (Sourse: made by the authors with information from CTR)

Fig. 17 Fishing Valleys division (Sourse: made by the authors with information from CTR)

FISHING VALLEYS NAME

Fig. 18 Surface division water surface (Sourse: made by the authors with information from CTR)

Fig. 19 Fishing Valley comb system (Sourse: photo taken by the authors) Fig. 20 Lakes inside fishing valleys (Sourse: photo taken by the authors) Fig. 21 Gates in fishing valleys “Lavorieri” (Sourse: photo taken by the authors) Fig. 22 Fishing valley “Le Manciane” seen from top (Sourse: Google maps)

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VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE VALLE

CONTARI NA DEGLI ORCOLI DEL CAVALLI NO DELL'AVERTO DI LI O MAGGI ORE DI SAN MI CEI DOGA' DRAGAI SOLO FI GHERI FOSSE GHEBO STORTO GRASSABO' LI ONA MOROSI NA OLI VARI PALEAZZA PERI NI PI ERI MPI E' SACCHETTA SACCHETTI NA SERRAGLI A ZAPPA

Fishing

3.2.1 Fishing Valleys an integral system

Fig. 23 Fishing Valley system. An integral system that have managed to integrate various activities that adapt and develop within it, creating a unique territory within the lagoon of Venice. This system has two seasons; Opening season or “montata” (spring - February to April 25 “SanMarco”) when the small fish (“pésse novêlo”) in the lagoon penetrates the valley and Fraima season (autumn - April 25 to Christmas) when the fish feed, grow and in December is fished if has the commercial size, in the case that has not reach the commercial size, the fish remain in the valley to continue growing for one more year. (Sourse: made by the authors with information from interviews and “La Pesca in Laguna” exhibition. Venice, October 2019.)

Fishing valleys are an integral system that have managed to integrate various activities that adapt and develop within it, creating a unique territory within the lagoon of Venice. This system has two seasons; Opening season or “montata” (spring - February to April 25 “SanMarco”) and Fraima season (autumn - April 25 to Christmas) and a serie of structures that allow the fish to remain in the lagoon even in the fall and winter, to raise them and consume them later when they reached their commercial size (2 years). The so-called fishing valleys refer to fishing as the main economic activity, but the vegetable cultivation has always been the predominant economic activity within from them. Fishing inside fishing valleys was better than in the lagoon, but the production is only 60 kg per hectare per year, which makes this activity practically only for self-consumption. To these two activities is added the hunting that has helped to counter the predation of fish by birds, but in more recent times has also become an important source of income, due to the great interest of sports hunters for the great number of bird species found in the lagoon, mainly in the central and northern part of it. If we focus on the issue of production, the tendency is to abandon fishing valleys because the investment required for fish production is more, compared to the result that can be obtained from fishing. In this sense, there are very interesting initiatives such as Galdino Vianello´s from “Agriturismo La Mancine” that keeps his fishing valley in use because he manages to recover the profits from the sale of fish by cooking and selling it in his restaurant. However, fishing in the lagoon of Venice is an activity that is gradually losing weight against the global market.

Fig. 24 Secondary canals, and Tamerice trees.

Beyond its economic character, as a man made territory fishing valleys have treasured a lot of knowledge about the lagoon and its processes to create a safe and controlled territory against the risks of tidal variations in the lagoon and that is where the importance of know and understand them, to apply their teachings in the adaptation of the territory to the new challenges that climate change represents.

Fig. 25 “Lavorieri”

Restore, Recycle and Renovate the Venetian Lagoon

3.2.3 A cycle in time and space Fig. 26 With the opening season or “montata” (spring February to April 25 “SanMarco”) Gates open with the first Scirocco wind in spring and the baby fishes penetrates into the valley trough the secondary canals; structures for the transport of water. And the gates closed on April 25th. (Sourse: made by the authors with information from interviews and “La Pesca in Laguna” exhibition. Venice, October 2019.)

Fig. 27 the fish remain in the secondary canals and hatchery, also called comb system until they reach a enough size so that the bigger fish can not eat them. (Sourse: made by the authors with information from interviews and “La Pesca in Laguna” exhibition. Venice, October 2019.)

Fig. 29 after that time, the fish are transferred to the primary and secondary lakes to remain the rest of the season where they will feed and grow (Sourse: made by the authors with information from interviews and “La Pesca in Laguna” exhibition. Venice, October 2019.) Fig. 28 in December, at the end of the Fraima season, only the big fish are fished and the others remain in the valley to continue growing. The structures for catching fish are called “lavorieri” and are part of very large tanks that communicate directly with the main sewer. The “lavorieri” are closed by the coils, formed by two vertical walls that form an acute angle which allows water to pass, but does not allow fish to leave

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Fig. 30 The fish that were not caught in December because they do not have the appropriate commercial size, remain in the comb system during the winter, since this system, being deeper and narrower than the lakes, allows the fish to not freeze and can survive during the winter. To protect these basins from the cold winter wind, hedges of tamerice (Tamarix gallica) were planted along their perimeter.

Fig. 31 Space occupation by season in fishing valleys (Sourse: made by the authors with information from interviews and “La Pesca in Laguna” exhibition. Venice, October 2019.)

3.2.2 What we learned from fishing valleys? A system built with dikes controling water by gates. A man-made territory to help its land and creatures to benefit from each other. A multifunctional space for settlements.

Fig. 32 Fishing valley structure (Sourse: made by the authors with information from interviews and “La Pesca in Laguna” exhibition. Venice, October 2019.)

Restore, Recycle and Renovate the Venetian Lagoon

Conclusion from researches Risks Sediment Reduction Barene Decrease Water pollution

Challenges Sea Level Rise (Flooding) Fishing Decline Fishing Valley Abandoned

Opportunities Requalification of the territory

Strategies Restore, Recycle and Renovate the Venetian Lagoon to adapt to climate change (SLR) and mitigate water pollution

Adaptation 1 Restore barene as an infrastructure. -create a buffer between lagoon and mainland. -improve the exchange of water. -increase sediments.

2 New dynamic flooding edge. -find new land to flood.

3 Create Dike-Gate System (Learn from fishing valleys) -control the new flood land. Hipothesis: Territory as a risk-control tool. (As the principle of fishing Valley)

Mitigation 4 Recycle fishing valleys -clean the water in the lagoon. -make them floodable at high tides.

-using them as sediments and marsh (barene) nursery

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Strategy 1 Restore barene as an infraestructure

Fig. 33â&#x20AC;&#x201A; An image of barene working as a wave buffer. (Retrieved from: http://www.lifevimine.eu/ lifevimine.eu/documenti.html)

Restore the barene that has been lost over the years due to erosion to use it as an infrastructure against the waves and to improve the exchange of water with the ocean and freshwater bodies and also to restore sediments (nature as infrastructure) Using the knowledge of ecological services to give more value to the Venetian Lagoon and go beyond the economy of the port and cruisers. Understanding that landscape can be use as infraestructure to deal with adaptation and mitigation to the scenarios of climate change that we are facing. In terms of layer approach in landscape ecology, the ground layer which comprises the soil, water and topography plays the role of the carrier for the new infrastructure in the barene increasing strategy. In another aspect, its role of providing basis for shaping the controllable flooding landscape influences a big range of the intervened area. And the changing method is derived from the analysis of mechanism in the better closed system and then will apply to a bigger open area.

Restore, Recycle and Renovate the Venetian Lagoon

Fig. 34 Barene as a wave buffer

Fig. 35 Barene help to create sediments in allochtonous way and in autoctonous way

Fig. 36 General interventions in punctual points to restore salt marshes that has been lost over the years and protect them from erosion. (sourse: diagram made by the author with information retrieved from: http://www. lifevimine.eu/lifevimine. eu/documenti.html)

Fig. 37 section of how the interventions can help to salt marshes to create sediments (sourse: diagram made by the author)

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Risks without Control

Risks with Control

“[…]You don’t have to try to reduce the area of the lagoon, You have to try to enlarge the tidal expansión of the lagoon […]” Emanuela Molinaroli PhD in Earth Sciences

Fig. 38 The diagram shows how not having a control system, the risks inside the lagoon expand to the mainland randomly, resulting in uncontrolled high water episodes that cause damage to settlelments. Fig. 39 The proposal is to create on mainland a series of controlled flood cells in order to understand how, when and where share the risks that are generated inside the lagoon. A kind of control room that may be related to the operating system of a new flood park in the lagoon. That is how the metaphor of fishing valleys can be reinterpreted.

Strategy 2 New dynamic flooding edge Venice have always been in contact with water and have known how to live in a certain harmonywith it, however, since the 20th century, the high waters have become increasingly frequent and intense due to erosion, loss of vegetation, climate change, among others. The risk of a catastrophe such as that of November 4, 1966 with 1.94 m is always present, so much so that on November 12, 2019, the second episode of highest high water recorded in the history of Venice with 1.87 m happened. To protect Venice from high water, since 2003 a mobile gate system (MOSE) began to be built in the port mouths, and when a high tide was foreseen, these floodgates would rise from the bottom of the lagoon to create a continuous barrier that would divide the necessary time the sea of the lagoon, to avoid the entrance of the water. It should be noted that this system has not been efficient to protect Venice against episodes of high water for several reasons, one of them, because construction work is not yet completed, another one because although MOSE was designed to protect from tidal surges as high as nine feet, it was only engineered to handle les than one foot of sea-level rise. This is an important issue, not only because rising seas increase the chances of higher storm surges, but also because higher seas would require the barrier to operate more frequently. Right now, engineers expect the MOSE barrier to be closed about ten times a year, usually for about five hours, until the tidal surge passes. Georg Umgiesser, an oceanographer at the Institute of Marine Sciences of the Italian National Research Council, estimates that with 50 centimeters (nearly 2 feet) of sea-level rise, it Will be closed once a day. With 70 centimeters (a Little more tan 2 feet) Umgiesser’s research suggests, the gates will be closed more often tan they are open. (Goodell J. (2017) The wáter Will come: Rising Seas, Sinking Cities, and the Remaking of the Civilized World) On top of that the problem is that there is no official institution that takes over the operation of the MOSE. So the conclusion could be that it is necessary to have a control room outside of the institutions that help to share the risk that the sea-level rise represents in a more controlled way in the territory

Restore, Recycle and Renovate the Venetian Lagoon

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Fig. 40 Lagoon edge 1924 Fig. 41 Lagoon edge 1971 Fig. 42 Lagoon edge 1990 Fig. 43 Flooding edge +1m Fig. 44 Flooding edge +2 m

42 21

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1990

+2m

+5m

Strategy 2 New dynamic flooding edge By looking at the scenario in 2050 built collectively, the ecological status of Venetian lagoon is tending to become a more semi-self-optimized system. The practical methods will be launched in order to maintain the balance. De Mose will be taken apart, the depth of the inlet will be reduced by simply placing stones, and more Barene vegetation will be restored with human intervention and eventually grow by itself. As a result, the amount of sediment in the lagoon base will reach the limit which can be handled under risk control.(9) However, even in the best scenario an increase of 50 cm of SLR can be given, which would represent a tide of 130 cm of high water for Venice. The Conterminazione Lagunare The Lagoon delimitation or conterminazione lagunare in italian is a man made boundary made by THE REPUBLIC to establish where the brakish water ends and where agricultural land with fresh water begins. But this man made creation has created a very hard boundary for the lagoon. We are going to focus in the conterminazione lagunare to forecast a new way to use it. And give it a new concept. Each conterminazione lagunare has its logic and each one faces a specific moment in the history of venice

Fig. 46 Lagoon edge 1990 Fig. 47 Flooding edge +2m Fig. 48 Flooding edge +5m

1924 discution of the big Venice 1971 The arrival of Marguera Port and the industrial city 1990, the new route of the delimitation line was approved, also including the bodies of water of the three mouths of the port and the island of S. Erasmo. Understanding that if we give more space to the lagoon for flood, creating a new dynamic flooding edge, that can be adapt to climate change,we can face the incertain future and Venice can be capable to adapt to the diferente situations that will have to face.

Fig. 45 Montly distribution of high tides >=+110 cm recorded in Venice, from 1872 to 2018 (Sourse: http://www.comune.venezia.it/it/content/ stagionalit-marea)

Restore, Recycle and Renovate the Venetian Lagoon

Strategy 3 Create Dike-Gate System (Learn From Fishing Valley) Hipothesis: Territory as a risk-control tool. (As the principle of fishing Valley) For the complexity the lagoon has, the ecosystem service approaches are suitable for explaining which consequences the researches and interventions will finally lead to.In the case of lagoon - fishing valley territory, the visible provision is to recycle, renovate and recreate the identity of up to the whole north lagoon and down to each reconnected dike. 0

Fig. 49â&#x20AC;&#x201A; Infrastructure Base (Access, Road, Boat) (Sourse: made by author with information from CTR)

Fig. 50â&#x20AC;&#x201A; Reconnected dikes with Bike Path (Sourse: made by author with information from CTR)

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Fig. 51 Process of Flooding In Agriculture Land & Fishing Valley by gates (Sourse: made by author with information from CTR)

Fig. 52 The diagram show wich parts of a fishing valley can be flooded during the high water season (lakes and canals), the comb system should be reinforse in order to protect fishes ((Sourse: made by author with information from CTR) Fig. 53 The image show the fishing valley flooded (Sourse: made by author)

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4 Application Strategy map

Fig. 54â&#x20AC;&#x201A; Strategy map of the new Venice Lagoon Park North (Sourse: made by author with information from CTR)

The role new projects play in the north lagoon becomes clear as it starts the elaboration of using landscape as infrastructure, applying new dynamic flooding edge by building dike-gate system and recycling potential fishing valleys for long-term use. All the main principles are initially standing at the tipping points when the main actions are taken, such as the removal of De Mose to stop the losing of sediments. Therefore, the basic item will be a mutual-improvement by the acceleration of barene growing and sediment increasing. Furthermore, the adaptive measure is the updating flooding edge drawn according to the delimitation changes by estimate sea level arise. At the same time, the traditional layer of fishing valley will be overlaid by partially level-up layer with multi-functional values. In a work, the projects which will be implemented either on the lagoon or in land will be a tool to share the risk of all the endangered parts surrounding the lagoon. The recycled and renovated territories will be planted with more efficient human intervention, so as to control the flooding area phase by phase and protect zones and cities with cultural value.

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25 Km

Territory As a Flooding Landscape

Fishing Valley As Barene Nursery Site

Fishing Valley As A Water Clean Machine

Pilot projects Test sides selection

Fig. 55â&#x20AC;&#x201A; Zoom of pilot projects (Sourse: made by author)

The three pilot projects implemented in the lagoon are respectively responding to three different issues to cope with the needs in Cavallino peninsula and Venetian lagoon under the premise of climate change. When we think of the benefits we are about to win, we can deduct back to the actions we need to do as the primary strategies. That is why we first study the marshland habitats types to against strong waves, phytodepuration to against eutrophication process to clarify intermediate services. Finally, we come to the solutions about accelerating accretion rate to reduce the submerge risk and optimize water quality.

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Project 1: Recycle Fishing Valley as Water Clean Machine Keyu Zhu

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Fig. 56â&#x20AC;&#x201A; Position behind Treporti town

Fig. 57â&#x20AC;&#x201A; Photos towards town/valley

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Introduction

Under the general background of implementing strategies all over north lagoon area. We choose the Treporti Fishing Valley as one of the pilot projects to explore the possible future of this unique territory. For its essential position located just behind the Treporti Town, it is the only fishing valley which keeps the closest distance to human settlements. In addition, according to field works, the original fishing, hunting, and agriculture activities present as vanishing gradually. There are some traces which show the environmental quality benefited from the traditional automatic mechanism in the previous time. Also, it indicates the potential the good aspect can be successive can turned into more inovated use. The practical qualification of which the Treporti Fishing Valley provides determines its potential to become a productive landscape in a more ecological way. The position near the Treporti town is considered convenient for collecting rain water from the run-off surfaces, and the water body composed by ditches, canal and four separate ponds enables connection of system and distribution of functions. Therefore, further technical approaches can be implemented into the territory to create a local park with significant role playing to bring fresh clean water for both ecosystem and recreation.

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Fig. 58â&#x20AC;&#x201A; Photos of 4 types of water bodies -Barene in the canal, ditch in the agricultural land, marshes in fishing valley, lake in fishing valley

While taking the chance to recycle the fishing valley and transform it into a new identity in the territory, the original value and enrionmental quality should be taken into consideration as well. The valley is composed of agricultural land, dikes to separate land from water, dikes to protect land from canal flooding, and the most essentail part - four water ponds inside valley.

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Fig. 59 Exchange between different water bodies Fig. 60 Water body / collecting zone division Fig. 61 Ditches potential to be in the system Fig. 62 New collection among ditches Fig. 63 Water collection network and discharge points

Recycle Fishing Valley as Water Clean Machine. Cavallino-Treporti area is facing the challenge of lacking fresh water to keep the salinity balance of lagoon. Under this premise, the collecting fresh water for the lagoon can be the most potential and reliable way to keep the balance. Therefore, rain water can be considered as an important source of fresh water. The first action is to distribute collecting zones according to the positions of the settlements and calculate the total run-off surface areas. The existing ditches in the agriculture land provide the low-cost transport base for building the system, and some new connections between ditches are established to complete the system. Besides the part in the agricultural land, the network in the urban context consists of pipes which go underneath and water whales open to the environment - the 2 types are differed in terms of the surrounding conditions and costs. In the last step, the collected rain water will be discharged into the distributed ponds which contains marshes to treat polluted water.

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Fig. 64 Overall Water System in Town-Valley Area Fig. 65 Project plan

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Fig. 66â&#x20AC;&#x201A; Birdview by following the path from Treporti Town to fishing valley Fig. 67â&#x20AC;&#x201A; Section: Water Cleaning System

Water Treatment Process When discharging collected rain water from ditches to subsequent part, it contains several components to clean water. Ditches to Energy Dissipation and Sediment Removal Pond: through pipes under the road ground, open ditches on the soil ground. Removal Pond to Marshland: through pipes under the dikes, optionally passing through lef and organic matter removal. Marshland to Lake: through fishing valley gates after long enough treatment. Lake to Outside: through fishing valley gates.

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Fig. 68â&#x20AC;&#x201A; Scene with new dike to separate removal pond from canal

Fig. 69â&#x20AC;&#x201A; Section: Discharging water from ditch to removal pond to marshland

Energy Dissipation and Sediment Removal The end of the this part of canal is transformed into removal pond in a lower-cost and more ecological than digging pond inside the 20cm deep pond. As the biggest inlet collecting rain water from urban area, itâ&#x20AC;&#x2122;s better not to interfere the original balance of the marshland. The new dike is built to separate this part of water from the canal. More vegetation and trees will be planted to temporarily make the water surface hidden. And the new design for the dike will be another entrance for attracting people to go inside the park.

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Fig. 70 Scene with recreation platforms as infrastructure to protect barene

Fig. 71 Section: Discharging water from marshland to lake by fishing valley gate

Marshland The size needed for an urban wetland depends on the volumes of water that have to be buffered and the extent to which the water netering the buffer is polluted. If the urban wetland serves to purify rain water run-off, the indicated design calls for a wetland surface that is 5% of the surface from which the rainwater runs off. (Reference: Hiltrud Pötz, Pierre Bleuzé , Blue-Grren Grid - Manual for resilient city) The application of one general strategy (restore barene as infrastructure) concentrate on purifying water with efficiently planting. And the recreation device in the park also functions as the protection structure for the new barene.

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Fig. 72 Scene with platform into water and floodable landscape - small ponds in dunes

Fig. 73 Section: vegetation around the clean lake

Possibility for a clean lake After the treatment by marshland, the water quality can reach the standard for people to get contact with. That is when more things can happen with the lake with variable egde and big surface. Wetlands can be designed to handle fluctuations in water levels of up to 30cm. The maximum fluctuation also determines the buffering capacity. This means that wetlands can serve as both buffering and purification systems. Realising sufficient storage capacity to buffer even heavy rainfall requires that 10-15% of the connected area must be suited for storing water, whether as surface water or also as wetland. (Reference: Hiltrud Pötz, Pierre Bleuzé , Blue-Grren Grid - Manual for resilient city) So the scences will change when the heavy rainfall happens or after long-time storage period. The lake has more capacity for accommodating water more than 30cm), so the edges can be design as suitable for each limits. And the landscape changes when people access water (naturally clean enough) in different time period. The small floodable landscaoe can be created, and the platforms can be designed for both in the water and on the land.

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Fishing Valley As Sediments - Barene Nursery Site

Fig. 74â&#x20AC;&#x201A; Zoom in Project 2 - Fishing Valley as sediments - bareneNursery Site Improve Access to Park Lagoon

Project 2: Fishing Valley As Sediments - Barene Nursery Site

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BETWEEN THE LAND AND THE LAGOON

Fig. 75 Retaining edge of natural land located in front of the retaining wall in via Pordelio, which is suitable for walking or being

Fig. 76 Picture about of separate diques inside of the lagoon, close to Canal Pordelio by Via della Marinona

Fig. 77 Map of emplacement Project 2; Territorial context of Cavallino Treporti and his relation between farmer- urban nodes- fishing valleys and the lagoon Fig. 78 Residual space in access to pedestrian edge, between Via della Marinona and Via Pordelio

Fig. 79 Via della Marinova pedestrian path and his cycleway located in the border of Pordelio Canal, It is used normally for cars during the day and the night

Fig. 80 Dike in the midle of Pordelio Canal as possible link betwween the land and the lagoon

The fishing valley of La Falconera is a desolate territory which is located in the northern sector of the Venetian lagoon, exactly in front of the city of Cavallino and still next to the Pordelio canal. The falconera is an island which formerly had an intensive use of its territory from the work of the fishing valley, a trade which is no longer booming due to changes in the global market and the maintenance cost of working a territory of such magnitude compared to the profits it can deliver. This territory, like the rest of the fishing valleys, is endemic to the lagoon territory, forming part of the culture and society of Cavalllino Treporti as well as its economy, where it is an essential part in the construction of the peninsula’s landscape together with the agricultural landscape and the dune landscape. This part of the territory where La Falconera is located close to the fishing valleys of Mesolo and Lio Piccolo between the peninsula in the Ca`Musestre sector and the nearby barene in front of the city of Cavallino. Despite having a good proximity between Mesolo and Ca`Musestre, in this sector there is no direct connection, so the only means of connection is aquatic through boats through Canal pordelio. This channel is the main water route in this sector of the lagoon, especially in Cavallino Treporti, which connects the peninsula from start to finish in its more than 10km long, linking the territory with the rest of the islands and peninsulas that make up the system lagoon. The Falconera is also close in a strategic position to the most densified Barene territories in the northern part of the lagoon near Cavallino, which are the largest barene reserve that remains in the northern lagoon product of the anthropic agents that they affect the lagoon territory during the passage of time.

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IMPROVE CONECTIVITY BETWEEN LAND AND FISHING VALLEYS Fig. 81 Map of Ca´ Musestre as a new edge to acces to the lagoon and fishing valleys, across of the dikes located in front of the territory

Fig. 82 Sketch showing the new link between Via della Marinona and the dike in Canal Pordelio close to acces since Ca´Savio. New Access thinking that in the future is possible link these new pathway with Mesolo and the others fishing valleys in the north Fig. 83 Sketch showing the new link between productive garden in Via della Marinona and the dike in Pordelio Canal, close to acces since Cavallino. The idea is make a loop across of the dikes between Cavallino an Ca´ Savio for the edge of Pordelio Canal Fig. 84 Sketch showing the connection between access to the camping area in the dikes and the area of urban policy improvements through the recycling of buildings for use in relation to the lagoon Fig. 85 Bird eye of the central area of the Via della Marinona and section related to the camping area

Fig. 86 sketch showing the residual space in the bus station sector in via pordelio

Fig. 87 Sketch showing residual space in access to via della marinona, with a proposal of bike path outside the retaining wall

The first action to be carried out in the territory is to improve the connection between the land part of Cavallino Treporti with the lagoon and the area of the fishing valley that privileges soft mobility. This is based on the use of the dikes in front of Ca’Musestre as new connection points. The idea is to create new paths and bike paths that connect the peninsula with the lagoon through the landscape, using the infrastructure of the dikes as a platform to make the connection between the land and the lagoon. Creating a circuit since Ca Musestre to Cavallino thinking that in the future it is possible to connect the peninsular territory with Mesolo and Lio Piccolo in the northern part of the lagoon through that the Pordelio canal. For its execution, the connection with the dikes closest to the edge of the territory is proposed through 2 low-impact wooden docks in the 2 entrances that it has via della Marinona. First in Ca` Musestre, (Fig. 9), where a 30 (m) long pier is the one that connects with a double crosswalk that allows bicycles. As also in Cavallino, (Fig. 10), where the pier measures 55 (m) and connects with via della Marinona in the agricultural sector, where a productive garden that mixes agriculture and public space is proposed. In the central part of via della Marinona, an urban improvement policy is proposed based on the recycling of buildings in poor condition at the edge of the road for future use related to social spaces, water recycling and links to the lagoon as an entry point to the northern lagoon park, (Fig. 11). The idea is to link this territorial area, which connects the pedestrian crossing of via della Marinona, with the dike closest to the peninsular edge through a 15 (m) dock that is the entry point to the proposed camping area in the dikes in front of Ca`Musestre. ( section A-A´)

Restore, Recycle and Renovate the Venetian Lagoon

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A´ 1

A-A´

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Fig. 88â&#x20AC;&#x201A; Collage showing a possible new use in farmer area in the border of via della Marinona as diversification of use and new social developments.

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Fig. 89â&#x20AC;&#x201A; Collage showing a possible new use in the border of Via della Marinona as a new access to the lagoon.

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RE-CYCLE FALCONERA FISHING VALLEY AS BARENE NURSERY Through the centuries the lagoon of Venice has not always been the same, it has had constant transformations of form caused not only by nature, but mainly by human intervention causing significant environmental and biological changes in the territory. One of the main problems that the Venetian lagoon must face is about the decline of the barene that it has suffered over the centuries as a result of the anthropic action in the lagoon territory. The barene is a main actor within the groundlayer of the Cavallino territory, thanks to its endemic properties it is a real contribution to the maintenance of the lagoon ecosystem, it is a water purifier, in addition to being a container of different types of habitats that can live in it . The Barene is really important for the lagoon in general, this because it improves local activity, such as fishing, protects the lagoon from flooding and improves biodiversity by creating the ideal habitat for different types of birds.

92 Fig. 90 Map showing the Project to improve connectivity between the lagoon and the land site in the Ca` Musestre sector next to the Falconera Territory Recycling Project. Fig. 91 Sketch about a possible future connection between Mesolo and Ca’Musestre through a bridge through the Pordelio canal.

Fig. 92 Eutrophication is the process where water produces an excess of nutrients, due to sediments that accumulate naturally or anthropically in its bottom.

That is why the main idea is to recycle the infrastructure of the La Falconera fishing valley, as a producer of barene for the benefit of the lagoon. For this it is necessary to adapt the infrastructure that this fishing valley possesses and give it a new use. At the moment the area of L a Falconera is an abandoned area without connection to the territory, and although it concentrates an important territorial area it does not take charge of its size. In this context, understanding that fishing valleys are a territorial area where all processes are controlled by humans, there is a good opportunity to recycle these areas and adapt them to the processes of changes that the lagoon is experiencing. For this, it is proposed to reuse the two interior lakes of La Falconera as reserve ponds that accumulate sediments over time, and that, in the near future, can grow barene inside of the fishing valley for subsequent renaturation in the lagoon context. Understanding that around La Falconera there are large areas of barene, which can be part of the renaturation in this area of the territory.

Restore, Recycle and Renovate the Venetian Lagoon

Fig. 93 bird’s eye that shows the relationship between the Falconera fishing valley and its immediate territory. The size of the fishing valley which is an area of approximately 566,000 square meters has great potential for use as a sediment producer in the Venice lagoon. currently the territory is used only in its agrarian part in dodne tourist homes are located that are renting for summer season

Fig. 94 Satellite Map. In the google satellite image it is possible to compare the size of the valley of the epsca of the Falconera with the city of Cavallino. It seems that the 2 lakes of the fishing valley are able to contain the entire perimeter of Cavallino city, which gives us an idea of its size in the lagoon territory

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96 Fig. 95 The fishing valley is recycled from its main structure. This is divided into 2 lakes, an area of agriculture and avanotteria and two access doors that control the flow of water. The idea is to assign the two main lakes for the accumulation of sediments that are isolated from the rest of the lagoon, protected by dikes, so they can function perfectly as sediment accumulation ponds.

Fig. 96 For the flow of water that enters into the fishing valley by dragging sediments, is consider using the same channel of the main structure of the fishing valley as the main access. The idea is that the water with sediments that enters the fishing valley system, is retained within the lakes which do the work of retention reservoirs, and through the doors controls the water output leaves the sediment in the inside lakes

Restore, Recycle and Renovate the Venetian Lagoon

98 Fig. 97â&#x20AC;&#x201A; As time goes by, accumulated sediments shape the shape of the territory and begin to change the landscape of the fishing valley. The accumulation process is slow and only when the height of sediments inside the lagoon is adequate, (40cm), will the process of barene growth and renaturalization of the territory begin.

Fig. 98â&#x20AC;&#x201A; Already when the growth of Barene inside the fishing valley is consolidated and it receives a claim for more spaces outside the limits of the dikes, the process of re-naturalization of the fishing valley with the territory will begin. For this entire process to occur, at least 200 years are necessary for accumulation and further development, which may be a bit late in the current ecological situation of territory.

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99 Fig. 99â&#x20AC;&#x201A; Sketch about the process of sediment accumulation in the Venice lagoon and its implication in the growth of more Barene. .

RECYCLE FALCONERA AS SEDIMENTS MACHINE The Barene formation process involves several conditions for its development, among which one of the most important is the minimum height that the accumulation of sediments must have inside the lagoon so that the barene begins to grow, around 40 cm high . The problem is that the accumulation of sediments within the lagoon, naturally, is a fairly slow process that accumulates per year only 0.2 cm in height. With these growth rates and considering that the anthropic action is making Barene disappear faster in the lagoon, it is good to think of alternatives that help the sediment accumulation process. One option may be the recycling of fishing valleys to create a controlled obstruction process to produce more sediments and accelerate natural accumulation. This process has a risk because to create more sediments through an obstruction process, it is necessary to have a controlled eutrophication process. A controlled obstruction process within a fishing valley that is an artificial territory with total human control, and considering that eutrophication is a chemical process that can be manipulated with the appropriate technical knowledge, is an appropriate case study for a pilot project of research in relation with the recycling fishing valley. Fig. 100â&#x20AC;&#x201A; Sketch that shows the process of clogging a lagoon where in the first part begins to receive nutrients and sediments that are gradually deposited in the bottom of the lagoon. This excess of nutrients causes the lagoon to begin an eutrophication process causing the growth of algae and other living things that when they die go to the bottom of the lagoon. Over time the lagoon loses depth due to the accumulation of sediments.

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Restore, Recycle and Renovate the Venetian Lagoon

101 Fig. 101â&#x20AC;&#x201A; Scheme of a possible reuse of a fishing valley as an infrastructure for sediment production. The idea in this design is to allocate an interior lagoon of the fishing valley to create a controlled clogging process which accumulates excess nutrients from intensive agriculture to be developed inside of fishing valley. The necessary sediments already accumulated are reserved and dirty water passes to another pond where the water is purified and put back into the cycle.

Fig. 102â&#x20AC;&#x201A; Collage showing a future scenario in which the fishing valley of the falconera, specifically its inland lakes, have accumulated sufficient sediments in its interior through time beginning the process of renaturation of this area with endemic vegetation and expansion towards the marshland more next. If it is considered an aid to the natural process of sediment accumulation, the accumulation of sediments for future growth of more barene could accelerate.

102

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Fig. 103 Collage that show a visualization of a future scenario with the growth of more “Barene” in the territory as part of a new pedestrian path through the dikes inside the Venice Lagoon Park .

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Territory As a Flooding Landscape

Project 3 Territory as a Flooding Landscape

Fig. 104â&#x20AC;&#x201A; Zoom in Project 3 - Territory as a Flooding Landscape

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Territory as a Flooding Landscape Among all the provisional area for flooding, this site is the most complex one. With its location close to the north polluted human habitat area, it is also related to the access to airport infrastructure, the multiple road infrastructure, the big surface of fishing valley and archaeology sites around. Therefore, based on the natural conditions and cultural potentials, the site is playing a role for showing images for the scenario in the way which the most adaptive and sustainable living and tourism can go. At the same time, the composition of the landscape enables building different structures for testing controllable flooding landscape. For example, to test the results when water goes through the combination of fishing valley gates and infrastructure gates, or only goes through double infrastructure gates. In addition, the wetlands are distinguished by the presence of water, either at the surface or within the root zones. The unique soil condition will be created in accordance to the frequency and period of flooding. For the biodiversity aspect, the landscape will be characterized by the presence or absence of certain vegetation. The whole process will be built together by human and nature by considering the periphery of neccesary services.

Fig. 105â&#x20AC;&#x201A; map of Venice lagoon and mainland with the delimitation of the transect to be developed

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106

107

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Restoring marshes

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From lagoon to mainland How is a territory protected from the elements of climate change?This project tries to demonstrate that the elements that until now have kept the fishing valleys safe inside the lagoon are possible to move to the territory. Although the strategies can be executed in parallel, it is necessary to know each one as together they will make the system work.

Restoringexisting marshesmarshes (barene) restore existingmarshes velme losed in 1955 restore in 1970 existingmarshes marsheslosed (barene) 2000 restore marshes losed in 1955

Fig. 106â&#x20AC;&#x201A; territory map with distinctive elements that characterize it.

new Flooding Cells restore marshes losed in 1970

Fig. 107â&#x20AC;&#x201A; Photos of the roads and rivers

restore marshes losed in 2000 new marshes

Fig. 108â&#x20AC;&#x201A; Map of existing barene and velme into the lagoon

new Flooding marsh ridge Cells Ecological corridors new marshes

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marsh ridge Urbanised areas

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existing marshes (barene) Restoring marshes restore marshes losed in 1955 existing velme restore marshes losed in 1970 existing marshes (barene) restore marshes losed in 2000 restore marshes losed in 1955

SLR +1.5 m New flooding areas SLR +1 m SLR +2 m SLR +0.5 m SLR +1.5 m lowlands 0m SLR +1 m new Flooding Cells lagoon restore marshes losed in 1970 SLR +0.5 m rivers new marshes restore marshes losed in 2000 lowlands 0m New flooding areas Restoring marshes Dike roads marsh ridge Fig. 109â&#x20AC;&#x201A; Restoring marshes with punctual interventions. In order for these interventions existing velme SLRFlooding +2tombe carried new Cells out, it is necessary to think of a lagoon Dike ring for cities sediment and vegetation bank that helps the desired maintenance and growth. Ecological corridors existing marshes (barene) SLR +1.5 m new marshes topography curve rivers restore marshes losed in 1955 SLR +1 m Urbanised New flooding areas New flooding areas areas marsh ridge

Restoring Restoring marshesmarshes

restore marshes losed in SLR 1970+2 SLR SLR +0.5 m m +2 m areas Ecological corridors Urbanised in risk of flooding restore marshes losed in 2000 lowlands 0m existingexisting marshesmarshes (barene)(barene) SLR +1.5 m +1.5 m SLR Urbanised areas 1955 Cells restore restore marshesmarshes losed inlosed 1955 SLR +1 SLR m +1 m newinFlooding lagoon Urbanised areas 1970 restore restore marshesmarshes losed inlosed 1970 SLR +0.5 m +0.5 m SLR newinmarshes in rivers risk of flooding existingexisting velme velme

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Restore, Recycle and Renovate the Venetian Lagoon

Dike roads Dike ring for cities topography curve exchange water gate Archaelogy site

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Fig. 110 General interventions in punctual points to restore salt marshes that has been lost over the years and protect them from erosion.(retrieved from: http://www.lifevimine.eu/lifevimine.eu/ documenti.html) Fig. 111 confinement structures for future barene consolidations. saturation of frames with velme sediments. (retrieved from: http://www.lifevimine. eu/lifevimine.eu/documenti.html) Fig. 112 photos of marshes flooded and not flooded working as an infraestructure against waves and water.

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New flooding areas

Restoring marshes existing velme

SLR +2 m

SLR +1.5 m New flooding areas SLR +1 m SLR +2 m SLR +0.5 m SLR +1.5 m lowlands 0m SLR +1 m new Flooding Cells lagoon restore marshes losed in 1970 SLR +0.5 m rivers new marshes restore marshes losed in 2000 lowlands 0m New flooding areas Restoring marshes Dike roads marsh ridge Fig. 113â&#x20AC;&#x201A; New floodable areas until +1m and +2m to enlarge the tidal expansion of the lagoon settlements that present flood risks lagoon existing velme SLR +2 mand Cells new Flooding Dike ring for cities Ecological corridors existing marshes (barene) SLR +1.5 m new marshes topography curve rivers restore marshes losed in 1955 SLR +1 m Urbanised New flooding areas New flooding areas areas marsh ridge

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Fig. 114â&#x20AC;&#x201A; existing dikes (mainly roads) that only need to be reinforced to face the sea level rise existing velme SLR +2 m Cells new Flooding

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restore restore marshesmarshes losed inlosed 2000 in 2000 marsh ridge

lowlands lowlands 0m 0m

new Flooding new Flooding Cells CellsEcological corridors

lagoon lagoon

new marshes new marshes

rivers rivers

Urbanised areas

Dike roads Dike roads

marsh ridge marsh ridge Urbanised areas Ecological corridors Ecological corridorsin risk of flooding 61

Urbanised Urbanised areas areas

Dike ring Dike forring cities for cities

EMU - European Post-master in Urbanism

Dike roads Dike ring for cities topography curve exchange water gate Archaelogy site

topography topography curve curve exchange exchange water gate water gate

topography curve rivers Dike roads exchange water gate Dike ring for cities Archaelogy site

topography curve

exchange water gate Archaelogy site

New flooding areas

Restoring marshes existing velme

SLR +2 m

SLR +1.5 m New flooding areas SLR +1 m SLR +2 m SLR +0.5 m SLR +1.5 m lowlands 0m SLR +1 m lagoon SLR +0.5 m rivers lowlands 0m Dike roads lagoon Dike ring for cities

new Flooding Cells restore marshes losed in 1970 new marshes restore marshes losed in 2000 New flooding areas

Restoring marshes

marsh ridge

Fig. 115â&#x20AC;&#x201A; creating a new dike ring to protect cities from the flood existing velme

existing marshes (barene)

SLRFlooding +2 m Cells new

Ecological corridors SLRmarshes +1.5 m new

restore marshes losed in 1955 SLR +1 m Urbanised New flooding areas New flooding areas areas marsh ridge

Restoring Restoring marshesmarshes

restore restore marshesmarshes losed inlosed 2000 in 2000 marsh ridge

lowlands lowlands 0m 0m

new Flooding new Flooding Cells CellsEcological corridors

lagoon lagoon

new marshes new marshes

rivers rivers

Urbanised areas

Dike roads Dike roads

marsh ridge marsh ridge Urbanised areas Ecological corridors Ecological corridorsin risk of flooding 62

Urbanised Urbanised areas areas

Dike ring Dike forring cities for cities

Restore, Recycle and Renovate the Venetian Lagoon

Dike roads Dike ring for cities topography curve exchange water gate Archaelogy site

topography topography curve curve exchange exchange water gate water gate

topography curve rivers Dike roads exchange water gate Dike ring for cities Archaelogy site

topography curve

exchange water gate Archaelogy site

New flooding areas

Restoring marshes existing velme

SLR +2 m

SLR +1.5 m New flooding areas SLR +1 m SLR +2 m SLR +0.5 m SLR +1.5 m lowlands 0m SLR +1 m new Flooding Cells lagoon restore marshes losed in 1970 SLR +0.5 m rivers new marshes restore marshes losed in 2000 lowlands 0m New flooding areas Restoring marshes Dike roads marsh ridge Fig. 116â&#x20AC;&#x201A; Creation of new flooded cells with exchange water gates that function asnew regulators currents. These gates should open lagoon existing velme SLRFlooding +2 mof the Cells ring for cities when the tide reaches more than 110 cm as it represents a risk for Venice and strengthen the system with ecologicalDike corridors that help Ecological corridors to store and filter the water of existing the riversmarshes and the lagoon to integrate later into the new lagoon. (barene) SLRmarshes +1.5 m topography curve rivers restore marshes losed in 1955 SLR +1 m Urbanised New flooding areas New flooding areas areas marsh ridge

Restoring Restoring marshesmarshes

restore restore marshesmarshes losed inlosed 2000 in 2000 marsh ridge

lowlands lowlands 0m 0m

new Flooding new Flooding Cells CellsEcological corridors

lagoon lagoon

new marshes new marshes

rivers rivers

Urbanised areas

Dike roads Dike roads

marsh ridge marsh ridge Urbanised areas Ecological corridors Ecological corridorsin risk of flooding 63

Urbanised Urbanised areas areas

Dike ring Dike forring cities for cities

EMU - European Post-master in Urbanism

Dike roads Dike ring for cities topography curve exchange water gate Archaelogy site

topography topography curve curve exchange exchange water gate water gate

Dike roads exchange water gate Dike ring for cities Archaelogy site

topography curve

exchange water gate Archaelogy site

Fig. 117â&#x20AC;&#x201A; photos of exchange water gates Fig. 118â&#x20AC;&#x201A; Collages of how the new territory should be transformed

Restore, Recycle and Renovate the Venetian Lagoon

EMU - European Post-master in Urbanism

Restore, Recycle and Renovate the Venetian Lagoon

References 1 D’Alpaos, L. (2010). L’evoluzione morfologica della Laguna di Venezia attraverso la lettura di alcune mappe storiche e delle sue carte idrografiche. Comune di Venezia, Istituzione Centro Previsioni e Segnalazioni Maree, Legge Speciale per Venezia. 2 Bozzato, G., Busarello, S., & Santostefano, P. (2014). Cavallino Treporti: Atlante delle trasformazioni di un territorio tra mare Adriatico e laguna di Venezia: 1552-2010. Cavallino-Treporti, Venezia: Associazione Culturale Tra Mar e Laguna & Comune di Cavallino-Treporti. 3 Ivajnšič, et-al. (2018) The fate of coastal habitats in the Venice Lagoonfrom the sea level rise perspective 4 Viganò, P. (2016). Territories of urbanism: the project as knowledge producer (First ed.) (S. Piccolo, Trans.). Lausanne, Switerland: EPFL Press. 5 Rosseto Luca, (2000) “The Management of Fishery in the Lagoon of Venice”, Padova. 6 Rapporto Statistico del Veneto 2018 7 Bon, et-al (2013) Atlante ornitológico Venezia. 8 “La Pesca in Laguna” exhibition. Venice, October 2019. 9 Developed Scenarios, EMU Program 2019 Fall 10 Goodell J. (2017) The wáter Will come: Rising Seas, Sinking Cities, and the Remaking of the Civilized World 11 R. K. Turner and others, an Ecological Economics, 35 (2000), 12 R. de Groot et al. / Ecosystem Services 1 (2012) 50–61 13 Corboz_Il Territorio Come Palinsesto 14 Secchi_Rethinking and Redesigning the Urban Landscape 15 Fox_Deep Ecology A New Philosophy of our Time 16 Madricardo_Mapping past and recent landscape modifications in the Lagoon of 17 Vcenecia y el de su laguna, análisis y propuestas para redesarrollar la ciudad y el entorno de la laguna y su economia 18 Bellafiore_Climate change and artificial barrier effects on the Venice Lagoon 19 ATLANTE DELLE TRANSFORMAZIONI (2014) 20 Global estimates of the value of ecosystems and their services in monetary units 21 Interviews P. Santostefano, cultural association “Tra Mar e Laguna”. personal communication, October 3rd, 2019. Cavallitno Treporti. Venice. Italy S. Lazzarini, Ittica Center s.r.l. Ufficio Acquisti, personal communication, October 8th, 2019. Cavallitno Treporti. Venice. Italy G. Vianello, fisherman, farmer and owner for 30 years of “Agriturismo Le Manciane”, personal cummunication, October 22th, 2019. Cavallitno Treporti. Venice. Italy A.Novello, Canal Pordelio’s fisherman, personal cummunication, October 25th, 2019. Cavallitno Treporti. Venice. Italy

EMU - European Post-master in Urbanism