Natural hazards and the sustainability of Himalayan hydropower

The history of Himalayan hydropower is dotted with severe accidents due to high-mountain hazards such as earthquakes, glacial lake outburst floods, and mass movements. Regardless, India is set to expand the development of large hydroelectric power projects, in particular in its Himalayan states. In Nepal, 85 new projects are currently under construction, and an additional 82 projects are under consideration. China approved plans to build the world’s largest hydropower dam along the Yarlung Zangbo River, and accelerated construction of hydropower dams along Tibet’s major rivers.

Clean, flexible, reliable and renewable energy is needed to satisfy increasing power demands, meet sustainability goals, and advance towards a carbon-free future. However, intensification of precipitation events, glacier retreat, and permafrost decay in the wake of global warming do not bode well for the future of high-mountain hydropower endeavors. For this reason, research is needed that offers quantitative assessments of hazards to hydropower and associated risks.

In this talk, I will showcase recent natural extreme events and their impact on Himalayan hydropower, and I will detail how regional assessments can help identifying river reaches that are exposed to natural hazards. While these assessments explicitly and quantitatively acknowledge uncertainties to guide disaster prevention, recent extreme events and their cascading nature underscore limits to hazard and risk assessments. These challenges to predict the diversity of rare and destructive events in the Himalayan environment need to be addressed to ultimately warrant that hydropower generation remains a sustainable undertaking.