Rome porous city: Potentials οn Urban De-Sealing in Rome’s Nuovo Piano Regolatore Generale for an Integrated Stormwater Management in its Territory

The management of hydrogeological risks in anthropized territories as well as the tutelage of the quality of its water resources, depend first of all on the availability of these resources over time. The social and scientific knowledge on the natural hydro-geological dynamics of territories gained so far (Holman-Dodds, Bradley & Potter, 2003; McGrane, 2016), facilitate the implementation of public policies in this direction, finding interesting examples globally. From the political strategic sphere, through the operational and socio-collective levels, the European continent leads this transition. Cities such as Rotterdam (Waterplan 2, 2013) or London (LSDAP, 2016) exemplify the construction of processes of conservative management of water resources, from the manifesto of socio-political intentions to its translation into implementation tools. In Italy, the Nuovo Piano Regolatore Generale di Roma (NPRG, 2008) from its incipit with the Poster Plan (1995) and the subsequent Piano delle Certezze (1997), affirming then as one of its founding pillars the Sistema Ambientale - articulated in the set of prescriptive norms Rete Ecologica (Ricci, 2009) - up to the Ambiti di Programmazione Strategica, such as that of the Tiber River, identifies the potentialities of the city for urban redevelopment and regeneration. In this context, after a synthetic analysis of four case studies in European ambit (Water Management Strategies of the cities of London, Berlin, Rotterdam and Copenhagen), this research focuses on the analysis of the components of the NPRG that come into play when proposing the urban regeneration of surface stormwater absorption areas in historically anthropized territories and in the levels of regeneration that can be achieved (Daily, 2000; Campos Venuti, 2005; Kanoi et al., 2022), considering the layers of history of the city's subsoil, in the search for an integration of these new strategies in the implementation tools already in place in the territory.