The International Hydropower Association held the World Hydropower Congress in Paris. The World Hydropower Congress brings together industry, government, finance, civil society and academia to set priorities for the hydropower sector. The theme, ‘The Power of Water in a Sustainable, Interconnected World’, focuses on hydropower’s role in delivering on the Paris Agreement and the Sustainable Development Goals. Andrea Castelletti was one of the speakers in the session on River Basin Development and panelist in the subsequent discussion moderated by IUCN with Julien Harou, Hellen Nabwala Natu, Amy Newsock, and Yunhua Chen. Andrea presented our recent results on the optimal dam filling applied to the Gibe III and Koysha dam on the Omo-Turkana basin.