Study of qanats as sustainable historical flood-management infrastructure and their application to environmental restoration of Málaga’s Merino stream

Mediterranean cities face the potential threat of floods intensified by climate change, characterized by rising temperatures, water scarcity, and increasingly frequent flooding events. In many cases, abandoned or semi-channelized peripheral streams heighten this flood risk. This article proposes a model for restoring urban streams using a nature-based solutions approach through green and blue infrastructures, introducing the innovative use of the qanat as a sustainable historical water system. The objective is to explore the feasibility of recovering streams as ecological infrastructure through the creative application of these historical blue systems. To this end, a theoretically driven, design-thinking methodology is applied to the case study of the Merino stream, located in a peripheral area of Málaga (Spain). The result is an integrated proposal structured around three ecological restoration and water-management strategies: the qanat, the restoration of riparian woodland, and a constructed wetland functioning as a retention basin. The article concluded that the qanat, as a historical technology, represents a resilient blue infrastructure offering economic, environmental, and social benefits for addressing flood risks.