Future-ready water systems: climate-smart decision support for smart water allocation and planning in India

Sena, D. R.; Sikka, A.; Kumar, G.; Mahapatra, S.; Rajkhowa, P.; Sharma, R.; Amarnath, G.; Bandyopadhyay, K.; Sarangi, A. 2025. Future-ready water systems: climate-smart decision support for smart water allocation and planning in India. Colombo, Sri Lanka: International Water Management Institute (IWMI). CGIAR Climate Action Program. 25p.

This technical report presents the development and preliminary evaluation of the Climate-Informed Irrigation Decision Support System (CI-IDSS) for enhancing climate resilience and water productivity in minor irrigation systems in India. Rising temperatures, erratic monsoon rainfall, and increasing evapotranspiration are intensifying water stress in smallholder rice-based systems, making traditional fixed irrigation scheduling increasingly ineffective. The Darpanarayanpur Minor Irrigation Project in Odisha is used as a representative pilot site to test climate-smart, data-driven irrigation planning approaches. CI-IDSS integrates APSIM crop modeling, CMIP6 multi-model climate projections, remote sensing-derived phenology, soil datasets, and optimization-based water allocation to support both seasonal planning and real-time irrigation scheduling. Field-calibrated simulations for the Swarna rice variety compare conventional continuous flooding (PTRCF) with alternate wetting and drying (AWD) strategies under historical and future climate scenarios. Ensemble analyses on preliminary results indicate that AWD particularly longer drying cycles, can reduce irrigation demand by about 10–12% while maintaining stable evapotranspiration and grain yield, demonstrating strong resilience across climate uncertainties. In contrast, conventional flooding systems exhibit higher sensitivity to rainfall variability and future climate stress. The findings highlight the potential of digital, climate-informed irrigation governance to improve equitable water allocation, reduce climate risk, and enhance sustainability in smallholder systems. Policy pathways include short-term AWD advisories and optimized canal releases, medium-term digital-twin irrigation management, and long-term basin-scale integration of water–energy–food nexus metrics. Although results remain preliminary and require multi-year validation, CI-IDSS provides a scalable framework for future-ready irrigation planning across Odisha, the Ganga Basin, and similar climate-vulnerable regions.