Extreme cities and isotropic territories: Scenarios and projects arising from the environmental emergency of the central Veneto città diffusa

Abstract

In Italy extreme cities and territories occur at the extremities of lagoons, coastlines, and river deltas, in hydraulically reclaimed and hydrogeologically instable areas, and those where the water supply network has been placed underground, channeled into piping, or removed altogether. These areas are now increasingly subject to natural calamities and extreme weather conditions, and the consequences of climate change and the fragility of the more and more impermeable and urbanized land surface are clearly evident. Isotropic territories are characterized by weak hierarchization of infrastructure and settlement. The metropolitan area of Venice, aptly described as a diffuse city (città diffusa), and other diffusely organized territories characterized by settlement dispersion are good examples of this phenomenon. This article reviews recent research at the University IUAV of Venice in a study on climate change and water forms, a project in which the profound relations between water networks, the geological nature of the terrain, forms of urbanization, and energy saving are tested out. The study of the territories of the Venetian metropolitan area provides a series of initial working hypotheses as to how the ongoing environmental emergency can become an opportunity for a development project of the city and the territory, capable of structuring its various parts differently.

Bank erosion in agricultural drainage networks: new challenges from structure‐from‐motion photogrammetry for post‐event analysis

“…Among the urbanized floodplains, the Veneto (northeast of Italy) is often taken as representative (Ranzato, 2011;Fabian, 2012), being characterized by different levels of urban sprawl and settlements (Fregolent, 2005) and by a dense network of channels and ditches (Cazorzi et al, 2013). Among the urbanized floodplains, the Veneto (northeast of Italy) is often taken as representative (Ranzato, 2011;Fabian, 2012), being characterized by different levels of urban sprawl and settlements (Fregolent, 2005) and by a dense network of channels and ditches (Cazorzi et al, 2013).…”

Flood dynamics in urbanised landscapes: 100 years of climate and humans’ interaction

“…In 1990–2010, in addition to the large-scale event of 1998 (K 5 in Fig. 5), the higher significance was also connected to the influence of climate and urbanisation on local flooding attached to the failure of the urban or peri-urban drainage system10111532.…”

“…Veneto is characterised by industrial facilities relocation and the diffusion of a manufacturing system based on small firms, whereas small dispersed rural settlements characterise the local social and cultural structure. These interactions resulted, especially in the 1970–1990 timeframe, in dispersed settlements developing within the network of large urban centres2832, mostly resulting in loss of agricultural landscape. This high level of urbanisation along with agricultural mechanisation and the regulation of watercourses determined a certain tendency to simplification and unification of the landscape32.…”

“…These interactions resulted, especially in the 1970–1990 timeframe, in dispersed settlements developing within the network of large urban centres2832, mostly resulting in loss of agricultural landscape. This high level of urbanisation along with agricultural mechanisation and the regulation of watercourses determined a certain tendency to simplification and unification of the landscape32. Differently, the changes over the 1990–2010 period mostly followed transport infrastructures (Fig.…”

“…This because changes in artificial coverage have a dual effect on floods: i) a direct hydrologic effect increasing runoff, and ii) an increase in the exposed number of goods. Furthermore, changes in the built-up areas can imply a modification to the drainage system, with changes to the drainage network and conversion to urban drainage system1532. The built-up area analysis comprises three reference years (1970, 1990, 2009) and the changes among them.…”