PO RIVER LANDSCAPE
IN THE ANTHROPOCENE ERA
THEME AND OBJECTIVE
OF THE WORKSHOP
The Landscape Of[f] Limits 2023 edition addresses the Po River case study focusing on two main themes:
– water, as an element and factor that builds territorial forms and natural ecosystems. Nowadays climate change and environmental crisis are producing extreme phenomena, from water scarcity to devastating floods, increasing risk situations and the dramatic loss of ecological, economic, social and cultural values;
– energy, as the integration of places, infrastructures and forms of land use capable of generating productive landscapes.
Along the Po River, the energy landscape traditionally organized around hydroelectric plants and the Caorso nuclear power plant (in an advanced stage of decommissioning) is now the subject of numerous research aimed at increasing its ecological and environmental compatibility, generating new values and functions within the complex system of ecosystem services.
In this perspective, the Po – with all its complex system of surface and underground waters – becomes, together with the territories it crosses, an exemplary case study and an extraordinary opportunity for the application and experimentation of the most recent water-sensitive design strategies.
The decommissioning process of the Caorso nuclear power plant, which began in 2001 and has reached an advanced stage in terms of decontamination and plant safety interventions, is now entering a phase aimed at the redevelopment and enhancement of the site as part of a Strategic Vision for the Po River, an action promoted by the Emilia-Romagna Region with the involvement of the territories: local authorities, citizens, protected areas, companies.in collaboration with different local stakeholders.
The goal shared by the Region, Province and Municipalities is to set up the conditions to fully seize the many opportunities that this new development offers at three different scales:
At the local scale, to initiate a process that defines actions aimed at the redevelopment of the Po’s environmental system. The stretch where the power plant is located is seen as a highly infrastructured post-industrial site but, at the same time, as a place with great potential in terms of ecological processes and biodiversity, due to its location and, simultaneously, to the exceptional nature of the condition generated by the subsistence of a prolonged nuclear constraint and the consequent scarcity of anthropic “disturbance” phenomena. The power plant is in fact located within the Site of Community Interest (SCI) – Special Protection Area (SPA) “River Po from Rio Boriacco to Bosco Ospizio”, an integral and structuring part of the director scheme of the Ecological Network of provincial and local level, and is adjacent to the SPA “Castelnuovo Bocca d’Adda”. These areas are located along the meander belt and in floodplains, adjacent to oxbows and banks of the river Po and its tributaries (Tidone, Trebbia, Nure and Chiavenna). These environments are particularly important because they host the largest number of nesting species of conservation interest in the Piacenza area. The presence of wetlands also makes the area important for the presence of amphibians and reptiles, while the fish population includes numerous species at risk of extinction such as pike and tench. In addition, the site stands out for the valuable floristic presence linked to aquatic environments with submerged or floating vegetation.
At the intermediate scale, intensify synergies with the Collaborative Pact for that stretch of the “Great River” that crosses the Piacenza, Cremona and Lodi areas, which involves two regions (Emilia-Romagna and Lombardy) and 34 municipalities, the Po River District Basin Authority, Aipo, three Reclamation Consortia, and two Water Management Companies.
At the regional scale to systemize the several initiatives envisaged for the Po at the national and European level: the renaturalization of the river area, included in the PNRR as a climate change adaptation measure developed in coherence with district planning of European relevance; irrigation and water resource management infrastructure to counteract the effects of recurring drought phenomena; the improvement of the safety of the main banks; river navigation; the “Vento” cycleway and the enhancement of slow and sustainable tourism in the area.
1. THE PO RIVER BASIN BETWEEN DROUGHTS AND FLOODS
Summer 2022 represents one of the peaks of media exposure that the Great River has been subjected to: the drought, the sixth recorded in twenty years and the most acute in the last 70 years associated with very high temperatures, has been the protagonist of scientific and opinion articles showing images of dry areas that have become beaches, of vulnerable and bare banks stretching almost to the point of touching, of sun-broken land.
Furthermore, in May 2023 (3-4 May and 16-17 May) a series of devastating flooding phenomena affected 44 municipalities in Emilia and Romagna, including mainly the metropolitan city of Bologna and the provinces of Forlì-Cesena, Ravenna, Rimini, Modena and Reggio Emilia. Heavy rains caused the overflowing of 23 water courses including the Santerno, Sillaro, Savio, Lamone, Montone, Rabbi, and Bidente-Ronco rivers, and the Idice, Quaderna, Ravone, Senio, Marzeno, Pisciatello, and Rigossa streams, There were also 250 disruptions and landslides in 48 municipalities in the affected area. Between droughts and floods, the Po River has been affected to an extreme level by the effects of Global Warming, making it evident how, in the current era of the Anthropocene, phenomena classified as exceptional, such as floods, inundations and extreme droughts occur in a continuum, interconnected and specular. Global Warming acts on planet Earth as a whole, but it is tangible in local manifestations and is now part of the daily experience of living people, generating an emotional and ethical impact on shared ecological consciousness. The trend is so evident, so enhanced by its extraordinariness, that the age of the Anthropocene is also an age of emergency, exception and record numbers.
2. THE PO SYSTEM
The Po fluvial area is a complex system, which needs to be investigated at different scales, from geographical to closer ones. A system that includes the tributaries and their catchment areas (extending over Piedmont, Lombardy, Emilia Romagna and Veneto), including the reservoirs for hydroelectric power production; the complex network of canalizations managed by various drainage authorities, which over the centuries has made possible the agricultural, productive and, to a minor extent, the transport of people and goods; the defense works, which include embankments (with the chiaviche and intake works) together with spillways, diversion and diversion canals, which regulate the passage of water within densely urbanized territories or those intended for agricultural production; hydroelectric (Serafini Island), thermoelectric (Piacenza) and, in the process of being dismantled, thermonuclear (Caorso) power plants; inert quarries, located according to logics that are often partial and incapable of controlling the effects on the river regime and aquifers.
On a territorial scale, the consolidated geographical imagery of the relationship between land and water in the entire Po basin identifies a peculiar landscape: glaciers and perennial snow deposits; Alpine torrents, steep and of inconstant flow, fed by melting snow in summer; Apennine torrents, with their multiple, unpredictable and sometimes treacherous forms, fed by spring and autumn rainfall; the Po and the plains, profoundly transformed by human action. But then, delving into the hydrosphere, the ‘chthonic’ world of underground waters takes on importance, where land and water mix in a slow and unstoppable movement and, beyond the visible, the artesian and underground aquifers feed the system (which we take for granted without fully understanding its value) of drinking water, on which much of our sustenance depends. Together, these data compose an articulated and complex representation of the Po Valley landscape, which reads its changing nature between fragility and resilience. Climate, soil, water, vegetation and infrastructure come together in a series of figures that constitute the common places of the Po River Landscape.
The Po is the most important Italian river, a multiform heritage of unparalleled wealth. It winds for 650 kilometers, crosses four regions (Piedmont, Lombardy, Emilia Romagna, Veneto), and has a catchment area extending for more than 70,000 square kilometers, including about a quarter of the entire national territory. The Po Valley is one of the European areas with the highest concentration of population and activity, where about 20 million people live and which generates half of the Italian GDP; its heart is the Po, which along its course contains a scenario full of unique and unknown riches.
On the Po, there is an extensive scientific and literary production and there is a large database of data and proposals, and a vast ecological, iconographic and geographical historical documentation. Along the Great River, there are eight regional parks and fifty protected areas of various nature. The entire river auction is also managed by two dedicated institutions: the Po River District Basin Authority and the Interregional Agency for the Po River (AIPo), which have competence mainly in hydraulic and environmental matters.
The river, however, lives a fragmented and uneven reality that sees alongside environmentally managed and culturally promoted stretches others where the river is just a large void in which its own and improper activities take place, outside of an effective overview.
The state of health of the Po presents critical aspects, destined to become more acute as a result of climate change, demanding an awareness that cannot be left to the sum of fragmentary interventions. There is no complete perception of its ecosystems and landscapes, a shared understanding of belonging to a river community, a widespread knowledge of the natural and cultural resources that characterize it, and those that are directly and indirectly supported by the river.
Water represents the very nature of the Po, as a resource and wealth in itself is the result of the combination of natural water flows in the underlying river basin with human activities that take place there.
Water is the backbone of the socio-ecological system and the eco-territorial network that make up the Po. The values and richness that it implies: the natural capital represented by biodiversity and the services that the ecosystem provides to the territory, the economic capital linked to multiple activities (irrigation, tourism, fishing, inland navigation), the social and cultural capital linked to the history of the territory and its works, local identities, the profusion of writings and works of art that have been the object of the water of the Po.
At the same time, the water we are considering has deep weaknesses, recalled by the Management Plan of the Basin Authority of 2015:
– eutrophication of surface water due to the high concentrations of nutrients (nitrogen and phosphorus) of civil and agro-zootechnical origin;
– pollution of surface and groundwater, in particular with respect to the presence of priority and new-generation chemicals;
– water scarcity and droughts, linked to excessive use of existing freshwater resources and in relation to global phenomena such as climate change and population growth;
– hydro-morphological alterations and the functionality of watercourses, depending on the needs of water use and/or urbanization of riverside areas;
– loss of biodiversity and degradation of ecosystem services of water bodies.
The central part of the Po has basically an artificial connotation, whose runoff regime is influenced by the hydrological, geomorphological, and climatological conditions, but also and above all by the hydraulic and soil defense systems that have been operated along its course and its tributaries. The Po river belt is an area in which geomorphological phenomena (erosion, deposition) characteristic of river dynamism partially persist; this allows the existence of coenosis of relevant naturalistic interest and of a high environmental diversity, where the shore defense works are not very extensive. Such dynamism allows maintaining of topographic situations and vegetal and animal coenosis characteristics of intermediate evolution states of the periphery wetlands. These processes are not preserved in a good state of integrity along the entire stretch involved and, in general, there is a loss of naturalness proceeding from mountain to valley.
The central stretch of the Po is still characterized by a considerable biodiversity unfortunately insufficiently protected.
The protected habitats are mostly riparian forest formations, mainly “alluvial forests of Alnus glutinosa and Fraxinus excelsior, mixed riparian forests of large rivers Quercus robur, Ulmus laevis and Ulmus minor, Fraxinus excelsior or Fraxinus angustifolia e gallery-forests of Salix alba e Populus alba, whose state of conservation is “inadequate” or “bad with a continuously worsening trend, as attested by the latest ISPRA Report. The same issue is faced by other typical and more strictly aquatic habitats such as the “Natural eutrophic lakes with Magnopotamion or Hydrocharition type vegetation”, the “Oligotrophic to mestrophic stagnant waters with Littorelletea uniflorae and/or Isoeto-Nanojunctea vegetation” or the “Mediterranean temporary ponds”. The Lombardy Region has identified the entire stretch of the Po as a “priority area for biodiversity” for the importance of its natural heritage which, although in many respects is now residual, is an ecological corridor to be protected and, above all, restored.
Between Piedmont and Lombardy, there is a concentration of the densest nesting populations of species of birds of conservation interest linked to well-preserved shores. Among these are the Common Tern (Sterna hirundo), the Little Tern (Sterna albifrons), the Little Courier (Charadrius dubius) and the Eyeball (Burhinus oedicnemus). These species are also present with lower densities in the remaining stretches of the river floodplain, along with other species of conservation interest, including the Nightjar (Caprimulgus europaeus) and the Montagu’s Harrier (Circus pygargus). Unfortunately, several of these species, such as the Tern, which until a few decades ago were more widely distributed along the Po, are in continuous decline, threatened by the artificialization of the river that has reduced islands and sandstones and by an often wicked use of the few remaining. Among the few positive signs in recent years there is the recent construction of the fish passage at Isola Serafini, which was a very serious interruption of ecological continuity especially for many species of fish such as the Coby Sturgeon (Acipenser naccarii). However, the morphological variation in the meandering stretch between the confluence of the Adda and the Mincio is not yet overcome. Finally, among the growing threats to the river’s biocenosis, there is the spread of many allochthonous species, such as the American shrimp Procambarus clarkii and Orconectes limosus, the bivalve mollusk Anodonta woodiana woodiana and especially many exotic fish species including the now known Silurus glanis.
The theme of agriculture along the floodplains of the Po and the possible flood strips is crucial and must be considered in its general and specific aspects.
The studies and special projects of the Basin Authority have told us that in the period from the 1950s to 2000 the area cultivated in the Po floodplains has increased significantly (18%); in particular, poplar groves and specialized arable land, now monocultural and often mono-sown, have increased, replacing the much more extensive and complex arboreal arable land, now completely disappeared. The areas under natural or semi-natural cover have decreased by about 8000 hectares (rate: -31%), with loss of peripheral biodiversity and fragmentation of the remaining areas. Urbanized areas, settlements and infrastructures increased by about 1,256 hectares (rate: +290%).
In recent years this model shows serious weaknesses. Bearing crops such as poplar groves are being dismantled because they are no longer profitable. The risks related to climate change, such as exceptional droughts combined with the water requirements of external cultivated areas, undermine the possibility of maintaining such large expanses of highly hydro-healthy crops. It is necessary to rebalance the general model of the use of floodplains by seeking new soil management mixes in which agri-environmental measures can play a decisive role in the production of ecosystem services to the territory that is adequately recognized also from the economic point of view.
The Po and its territories are a compendium of historical, artistic, and literary values.
The history of Italy and the relationships between its people have been conditioned until recently by the opportunities and barriers that the river offered. Art has flourished over the centuries in the cities that gravitate directly around it (such as Turin, Piacenza, Cremona, and Ferrara) or through its primary tributaries (such as Mantua, Parma and Pavia). The braid of the villages that overlook it houses abbeys, churches and other monuments of great historical importance.
Gianni Brera, in his “Invectiva ad Patrem Padum” (1963), boasted of having the Po as his father while recognizing its traitorous character and glory of having received the title of “knight of the Po” after Zavattini and Bacchelli. The saga of Don Camillo and Peppone who left us Guareschi takes place on the banks of the Po. Gianni Celati, with Narratori delle pianure (1985) and Verso la foce (1989) and Paolo Rumiz on numerous occasions have made it the object of research on the relationship between the river as a living entity and the people who inhabit it, walk along it and cross it. The Po has inspired directors such as Michelangelo Antonioni, Cesare Zavattini, Roberto Rossellini, Luchino Visconti, Alberto Lattuada, Mario Soldati, up to Ermanno Olmi who set his last film.
The cultural heritage deposited in the river landscapes is represented in a series of shared narrations and images (by painting, cinema, photography and literature). At the same time, it is continuously modified by unpredictable pressures: the new multi-ethnic dimension of the community (with 18,6% of foreign residents, Piacenza is the city with the highest number of immigrants in Emilia Romagna); the new “demand for nature” from urban populations; the recent transformations of the river landscape as a result of natural processes (invasive alien species).
7. PLANS AND PROJECTS
FOR THE PO RIVER BASIN
For the Po, as for most European rivers, the standard functioning of the water system involves works and actions to allow the regular and controlled flow of water from the springs to the sea. Along the way, this water feeds various ‘economies’ supported by an administrative and management system that reflects the economic, political and cultural organization of a large territory for which water is the main ‘common good’. The model is based on what, in our latitudes, is called the water cycle. Perpetuating unchanged for millennia in the hydrosphere, it ensures the continuity of state transitions between seas, atmosphere, snowfields and glaciers. The functioning model of rivers contemplates the exceptional flood event as the only possible contingency, capable of undermining what, not surprisingly, is called the defense works: embankments and diversion systems, and of causing major disasters. This is what we have been brought up to think since childhood.
The drought has introduced catastrophic scenarios of a diametrically opposite sign, dramatically posing the relationship connecting the global environmental and ecological crisis with the effects of climate change. Public discourse is questioning the role of water as a resource and the urgent need to introduce measures that will touch political choices, production processes, collective and individual consumption, to the point of highlighting a rupture between the principle of water for life and water for agriculture and its production chains that tests the resilience of the dominant development model that has so far oriented interventions to transform different environments. Need to overcome the episodic nature of interventions of an emergency nature in order to address the problem with an integrated approach, capable of observing phenomena at different scales, of bringing to synthesis multiple knowledge, but above all to measure oneself with transformation processes in an adaptive way, addressing in an integrated form decision-making, implementation, realization and management aspects; to work, therefore, along a multidimensional and dilated timeline to include different natural and anthropic cycles and processes.
The discussion around the need to field an integrated national and watershed-level strategy highlighted the need to broaden the range of feasible technical solutions through the implementation of new and modern practices and measures to reduce water demand and avoid water waste: saving in civil uses through the reduction of civil network losses and consumption; saving in agricultural uses also through an intelligent reshaping of the regional programming tools of the new CAP to make them capable of directing farmers’ choices toward less water-demanding crops and agri-food systems and more efficient irrigation methods. Supply-side strategies should also be revised to get to the point of recognizing the importance and usefulness of ecosystem functionality starting with a greater focus on aquifers: the best place to store water is the water table, whenever there is one. However, the main obstacle to the infiltration of rainfall into the soil is given by that mighty and widespread set of human interventions put in place for centuries, exacerbated in the past decades and still prevailing even culturally, so much so that they are considered symbols of civilization and progress. For this reason, it is essential to restore all those practices that allow water to be retained on the land as much as possible and to encourage actions to restore the ecological functionality of the land and restore ecosystem services. At the same time, the reuse in irrigation of wastewater should be promoted.
At present, a number of infrastructures are planned in the Po River District aimed at providing rapid responses to some major critical issues brought about by recurrent water scarcity crises, including the salt wedge intrusion barrier in the Po Delta and the two reservoirs in the Val d’Enza and Val di Lanzo, financed by the Infrastructure and Sustainable Mobility Ministerial Decree No. 259 of August 29, 2022. These interventions are the subject of controversy in relation to their environmental impact and actual effectiveness from the point of view of integrated water management. At the local level, at the suggestion of some trade associations and reclamation management bodies, the design and implementation of water collection reservoirs in hillside areas are under discussion.
The design and implementation of strategic water infrastructure for the Po River District is underway. In particular, the works envisaged by the Action Program (M2C4.3 I3.3) Renaturation of the Po Area included in the PNRR, as a climate change adaptation measure developed in coherence with district planning of European relevance.
MORE INFO :
Il risveglio del fiume segreto
In viaggio sul Po con Paolo Rumiz
Movie directed by Alessandro Scillitani
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Mario Soldati: viaggio nella valle del Po
Una grande inchiesta televisiva
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Caorso IV nucleare
Property of Enel Italia S.p.A.
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