Blue infrastructures for ecological regeneration. The recovery of mining sites in Hamburg and Rome

This paper explores the regenerative potential of water in post-industrial landscapes, with particular attention to disused quarries along the Elbe in Hamburg and the Aniene in Rome. Water is interpreted as an active ecological agent capable of transforming quarry lakes into continuous blue-green infrastructures that integrate biodiversity, heritage, mobility, and public space. Through a critical comparison, the study demonstrates that the former Kaltehofe waterworks in Hamburg and the surrounding quarries constitute a laboratory of transferable strategies for ecological reconnection, site memory, and climate resilience. In line with Sustainable Development Goals 6, 8, 11, and 15, and with European biodiversity policies, the article interprets the landscape transformations triggered by water as a model of ecological and cultural regeneration, recognising the Roman quarry lakes as potential nodes in a broader urban environmental network.