Sediment is physical matter and, as such, is usually studied in the physical and natural sciences, such as chemistry, geomorphology, or hydraulics and hydrology. However, sediment is also deeply embedded in society and politics. Sediment flows are affected by river transformation and, in turn, affect river management. This article highlights the changing ways in which society has considered sediment in the Rhône River (France). In the early-modern historical period (16e-18e c.) sediment was generally considered a blessing. However, the contemporary evolution of the Rhône's industrialisation, river engineering, and governance has challenged this perspective. Today sediment is more likely to be viewed as a threat. The concept of the hydrosocial cycle is a useful framework within which to describe the variety of ways societies have understood river sediment. The variation is caused by, and in turn affects, the meaning and representation of sediment, the structure of land and water governance, the nature of sedimentary and water resources, and the materiality of sediment and water, mediated by technology. This article aims to open the issue of sediment to the social sciences through a dialogue between history, human geography, and political science.