This article explores the operating conditions of coastal landfills in Lebanon, where a waste crisis has been going on since 2015. It focuses on two embankments built by the authorities on Beirut’s coastline (at Borj-Hammoud/Jdeydeh and Costa-Brava), which extend the footprint of old, saturated dumping sites into the sea, while creating new reserves of land. By following the flows of waste and construction materials dumped on the coast, this article analyses how the city is clearly expanding into its coastal space. Based on interviews with public and private actors and an analysis of satellite images, this investigation demonstrates that the landfill mining and the resulting land creation raise political and economic issues and opportunities but provide little benefit to local populations.