This project investigated how water is stored in, and moves through, a Himalayan river system (the inter-linked Beas and Sutjej catchments) in northern India at daily to decadal timescales and to use the resulting insights to develop and tested a robust model of the whole system that can be used to inform current and future decision making to support the sustainable development and management of the region's water resources. Building on the success of the MICCI project (within the Changing Water Cycle - South Asia programme) in the region, the project addressed user requirements centred on understanding and managing the effects of climatological and hydrological variability and socio-economic development on delivery of critical ecosystems services, notably the irrigation water supply-hydropower generation-flood risk management nexus.

A combination of state-of-the-art modelling, field studies, satellite-based remote sensing and observation used to improve the process-based understanding of Himalayan water resources availability and quality, considering meteorology, surface-water, groundwater, seasonal snow, permanent snow/ice, soil and vegetation. These stores and flows were considered within a 'whole-system' framework that explicitly recognises their inter-dependencies and interactions.

The improved understanding was used to set-up, calibrate and validate a robust system model of the river basins using the widely used Water Evaluation And Planning (WEAP) software system. This model integrated both 'natural' catchment processes and human modifications of the river basin system into account. These latter include irrigation, hydropower generation, and inter-basin water transfers. The whole system model was used to understand how the impact of climate change, land-use change and population growth will affect water resources (including flood risk management), water demand (irrigation and public water demand) and inter-sectoral competition for water supply (for water transfers, irrigation and hydropower) through their interactions with the hydrological cycle. The results were used to inform decision-making and support the sustainable development of India's water resources and hence long-term socio-economic growth