Hydropower resilience in the Narayani River Basin: Multi-scenario insights on reliability and vulnerability under climate and land use change

Abstract

Hydropower systems are highly sensitive to climate variability, necessitating robust assessments for long-term sustainability. This study employs the SWAT hydrological model for the Narayani River Basin in the Hindu Kush Himalayan Region. Climate change projections from General Circulation Models (GCMs) are integrated with land use change scenarios to assess their combined impact on hydropower performance through Reliability, Vulnerability, and Resilience (RVR) analysis. Reliability is the system's ability to consistently meet demand, Vulnerability evaluates its exposure to climate disruptions, and Resilience gauges its capacity to recover after disturbances. Future climate scenarios “wet-cool”, “wet-warm”, “dry-cool”, and “dry-warm” capture projected variations in temperature and precipitation. Results reveal significant seasonal and systemic disparities: snow-fed systems exhibit superior reliability, consistently exceeding the 0.95 reliability threshold post-monsoon due to sustained snowmelt, whereas rain-fed systems struggle during winter and pre-monsoon periods. Despite lower reliability, rain-fed systems maintain low vulnerability (<0.5) across all seasons, highlighting their inherent resilience to disruptions. Monsoon conditions enhance performance for both systems, achieving near-perfect resilience (score = 1), though dry-warm climates exacerbate vulnerability due to increased water scarcity. The analysis underscores critical climate-driven risks, with snow-fed systems being more affected by snowmelt variability and rain-fed systems by groundwater recharge limitations. To mitigate climate uncertainties, this study recommends adaptive strategies, including prioritizing enhanced water storage over run-of-river projects. By integrating multi-model GCMs projections with RVR metrics, this research advances hydropower resilience planning, advocating for localized climate adaptation and infrastructure investments to ensure sustainable energy security in a warming world.