Soil Displacement. Landscape Project as an Infrastructure Across Building Geography and Grounding Metabolism. The Case Study of Pialassa Piomboni Constructed Wetland in Ravenna

In current circumstances, man has the great responsibility of better managing the effects and products of those intense anthropic processes—such as waste disposal or excavation materials—which cannot be assimilated in a reasonable time by spontaneous renewal cycles. A systemic approach is needed for coordinating man-made metabolic procedures concerning the inevitable phenomena of urban and territorial transformation and ecosystem protection, admitting that one can be consequent and functional to the other. By being open to a strongly interdisciplinary approach, landscape design can offer precise and contextualized design solutions which may involve large temporal and spatial scales in reference to the extension of the problem. The proposed case study of the Ravenna commercial docks shows how the progressive expansion and continuous maintenance of the seabed through dredging has led to the creation of newly constructed wetlands in continuity and balance with existing ones. In particular, the excavated material was transferred into Pialassa Piomboni (protected wetland pSCI and SPA) through topographic modeling suitable for improving the ecological state of the humid area. After the intervention, the Pialassa area is expected to increase its ecological potential. Such an approach has turned waste treatment into an opportunity, allowing the wetland system to grow stronger and reducing costs compared to transporting the material to a remoter site. Several years late, building on the site is still ongoing in 2020. The project time schedule was not completely adhered to, with a strong impact on the expected outcome. In light of this experience, the contribution discusses different solutions for integrating and observing the regenerative time of nature in the design process and soil handling in spatial planning by activating new metabolic processes in its replacement in the environment.