Numerous studies have highlighted the negative consequences of dams (long-term alterations of Earth systems and social and economic injustices), and have questioned the sustainability of dams, i.e., the capacity of dams to meet the social, economic, and environmental needs of the current generation without compromising the needs of future generations. After having stalled in the 1990 s, dam construction has entered a new period of growth. Recent research has shown that this new phase in dam building can be explained by the promotion of hydropower as clean energy. To clarify the continuing debate on the construction of dams, particularly on their impacts and sustainability into the future, this paper examines the discourses on dams within the public domain. We used a collection of newspaper articles published in Le Monde from 1945 to 2019 on dams that were planned and built throughout the world (n = 1471). Results show a rise of different discourses on water infrastructure, which with time deal less with positive technical appraisals and more with controversies. Since the mid-2000 s, new arguments are defended (green energy) and new controversial discourses on the social and economic sustainability of dams (bearability, equitability) have emerged along with environmental questions (greenhouse gas footprint). These discourses reveal different understandings of sustainability which increase the complexity of the debate on dams. Results from this study suggest a need for a stronger dialogue between the scientific and public domains on the impacts of dams. Knowledge transfer and exchange would be particularly beneficial on ‘renewable energy’ and ‘green energy,’ and alternative modes of governance regarding dams.