Reinventing the wheel – The preservation and potential of traditional water wheels in the terraced irrigated landscapes of the Ricote Valley, southeast Spain

Abstract

Lifting water is crucial to irrigate agricultural terraces in the Mediterranean region. But the energy demand and emissions of modern forms of water pumping have increased, while many traditional water wheels, which lift water at zero direct emissions, have been abandoned. We explored the state of preservation and the potential for the deployment of traditional water wheels known as “norias” in the Ricote Valley of southeast Spain, where some are still in function, while also investigating the reasons for their widespread abandonment. A mixed method approach is used here to combine GIS-based methods, an expert survey, and a technological and socio-economic assessment of noria renovation. Our findings show that norias in the Ricote Valley have mostly been replaced by thermal-engine water-lifting technologies. The reactivation of traditional irrigation technologies, many of them lying dormant but still standing, could contribute to reducing the high energy demand and the resulting emissions of irrigation systems in the Mediterranean region and beyond. It was estimated by data extrapolation that 16 renovated norias included in our analysis can irrigate 140.3 ha in the Ricote Valley, for a total achievable power of 23.8 kW. To irrigate a similar surface applying diesel motor pumps would produce up to 148 tons of emissions/year and cost up to approx. 70,000 €/year based on a price of 1.25€/l diesel for a maximum of 8760 working hours/year. In the case of electric pumps, we estimate that up to 55 tons of emissions/year and costs up to approx. 48,000 €/year can be saved. Therefore, we argue that rediscovering traditional technologies has potential to contribute to achieving climate actions that reduce GHG emissions (Sustainable Development Goal 13). Moreover, these technologies provide multiple functions and services for a sustainable life on land (Sustainable Development Goal 15), which needs to be considered within a holistic approach.