Climate change, out-migration and agrarian stress: the potential for upscaling small-scale water storage in Nepal.
Climate change could have a critical impact on agriculture in Nepal due to changes in the variability of water availability and associated uncertainty. In this context, small-scale water storage - most notably ponds and tanks - can moderate this variability. This report explores the potential role of small-scale storage infrastructure in two subbasins within the larger Koshi Basin in central and eastern Nepal. It is shown that upscaling small-scale storage requires an appreciation of the other drivers of change in agriculture aside from climate, and identifies the social relations and dynamics which could mediate in future interventions for their success. A distributed hydrological model was used to assess the impacts of climate change in the two subbasins. In both subbasins, precipitation is highest during the monsoonal months, June-September, which is then reflected in the water yield and evapotranspiration values. In the Indrawati and Pankhu subbasins, annual total water yields are 74 and 57%, respectively. Therefore, both subbasins have underutilized water resources and high potential to develop storage infrastructure. Climate change projections suggest dry-season water shortages as well as increases in variability, which make waterstorage systems increasingly important. However, through an analysis of existing irrigation systems with and without storage, a number of constraints to upscaling small-scale storage become evident. First, out-migration is affecting male farmer incentives to invest in irrigation as some farmers prefer to pursue livelihoods outside of farming rather than investing in dry-season production. Second, the increased work burden of women left behind and often with limited access to funds constrains women from taking a lead in maintaining existing irrigation systems, particularly when they still have a limited role in management of communal infrastructure. Third, management institutions for existing water resources and stress on community relations due to out-migration impact the success of past interventions. Last, inequitable landownership structures and property rights have not only skewed the distribution of benefits from past interventions but also contributed to underlying conflicts over water. Unequal power relations in decision making have also shown to be a concern, particularly when the priorities of households with regard to water storage solutions vary according to one's position in the agrarian class structure. It is clear from the research that, while small-scale water storage has the potential to significantly strengthen livelihoods in the Nepali hills, it is necessary to tailor projects to the existing socioeconomic context. This includes, first, the need for targeted engagement or training for new interventions for potential migrant youths, and the women and elders who stay behind. Second, it is necessary to identify and understand successful irrigation management institutions in potential beneficiary communities, so that they can be harnessed. Third, it is important to build new infrastructure of an appropriate scale according to levels of out-migration and other social stresses. Fourth, it is critical to integrate water-storage development with appropriate agricultural extension. Last, storage development should be integrated with water basin management at a larger scale to ensure the sustainability of springs and other resources which feed new infrastructure.