Tapping into tradition: a multi-method approach for reviving Tanka for climate-resilient water management in Ahmedabad

Abstract Ahmedabad, a city that is layered with centuries of traditional knowledge systems, showcases a unique adaptation to socio-environmental and economic challenges. One such system is the Tanka, a traditional , low-tech underground rainwater harvesting structure that is typically lined with lime and embedded beneath domestic courtyards in the historic city. These structures, maintained through ritualistic cleaning and seasonal preparation, reflect a sustainable legacy of self-reliant water management. In this paper the potential of reviving Tanka as a decentralised water infrastructure for climate-resilient urban management is investigated. In this study, climate resilience refers to a city’s ability to anticipate, absorb, adapt to, and recover from climate-driven extremes particularly water scarcity, heatwaves, and heavy rainfall. Tanka systems contribute to resilience by enabling decentralised water storage, reducing pressure on centralised infrastructure, enhancing microclimate regulation, and serving as emergency reserves. Focusing on the UNESCO World Heritage site of Ahmedabad, where nearly 10,000 Tanka are believed to exist, the study examines resident’s perceptions and institutional challenges in integrating privately owned Tanka for broader public utility. Drawing from qualitative methodologies, the research employs a triangulated approach: in-depth interviews with 25 residents of historic houses, a critical review of urban water governance and municipal policy documents, and focused group discussions (FGDs) involving both community members and domain experts. The findings highlight a promising 90% willingness among residents to reintegrate Tanka water into the urban system. However, the current top-down governance framework dominated by the Ahmedabad Municipal Corporation (AMC) lacks mechanisms for incentivising citizen participation and heritage-based water reuse. This study advocates for a co-governance model that combines state capacity with citizen agency to address urban water stress while reinforcing heritage conservation. Furthermore, it proposes a scalable planning framework rooted in traditional practices, adaptable to other Indian cities and new settlements. Repositioning Tanka within a broader discourse of sustainable development, the paper suggests that reviving such vernacular systems offers a low-carbon, culturally embedded solution for managing urban resilience in the Anthropocene.