Scaling up Spring Revival in the Himalaya: Graduating from Spring-Centric to Aquifer-Centric Nature-Based Solutions

The Himalayas are undergoing rapid climate change, and the prevailing narrative has revolved around glaciers and river hydrology. While ironically, in the densely populated Himalayan mid-hills, it is the network of rain-fed springs that are the principal source of drinking water. Recent studies highlight the worrying trend of these springs drying up affecting women and children the most. Reviving these springs by artificial recharge using geohydrology and isotope approaches has shown positive results. However, the ‘spring-centric’ approach is too intensive for scaling up, and we explore the possibility of using the ‘mountain aquifer’ as the unit of planning. In this study, we investigate the inner workings of the mountain aquifer system using environmental isotopes and landscape-level recharge experiments. Are the aquifers disjoint or connected? Do they have annual or multi-year storage capacity? Can these aquifers be recharged using landscape-level approaches? The purpose of this research is to examine these questions in an action research mode using biophysical and socio-economic approaches in the context of Sikkim Himalaya. The findings show that mountain aquifers are connected by fractures, having multiple recharge and discharge points along the elevation gradient. These rain-fed aquifers are sensitive to rainfall patterns as they do not have the capacity for multi-year storage. Landscape-level recharge projects on hilltop forests benefitted springs in the lower and middle part the most, and an intensive socio-economic assessment further reinforced the theory of connected aquifers. Based on this understanding, we propose scaling up spring revival, by graduating from ‘spring-centric’ to ‘aquifer-centric’ approaches.