The Egyptian state built the High Dam at Aswan (1960-1971) to sustain its rapidly growing population and its status as politically independent postcolonial nation. But could the state sustain the High Dam? What political, social, economic, environmental, and structural ecologies did such support require? Anxiety about the dam’s safety marked a slew of popular publications and rumors that emerged during and after the dam’s construction. Such texts envisioned a destructed Nile valley flooded by waters released by a broken or bombed dam. Initially raised by funders in 1956, these disaster fears surfaced in Egypt in response to catastrophic dam failures in Europe during High Dam construction and wartime dam bombing, including in the conflict with Israel. Futuristic fears of catastrophic downstream flood mirrored real destruction on the other side of the dam—the upstream flooding of Nubia by the new reservoir and the land’s destruction by salvage archaeological teams. These anxieties revolved around stone. Egyptian officials worked to allay fears by publicizing the technological and scientific specificities of the dam: they contrasted the mountain-like rock earthworks of the High Dam to the “thin” and “curbed” concrete walls of many European dams and highlighted the structural benefits of rock fill, which would simply fall back into the Nile’s channel as a “natural dam” if imploded. Likewise, scientists and popular writers imagined the material properties of the Nubian sandstone underlying the dam—its propensity to become saturated during high floods and thus weigh heavily on the region’s seismic faults, or to develop a congeries of subterranean waterways from the dammed water’s corrosive power. This paper draws on several recent anthropological and literary critical studies of the materiality and ecology of stone (Cohen; Tilley; Gordillo) to contextualize popular concerns and theories of dam failure in Egypt. Building on existing studies of the High Dam politics of expertise (Waterbury, Mitchell, Shokr), I use published and unpublished government documents, pulp fiction, film, and the press to argue for the political salience of popular opinions that the dam exceeded technological control or mastery and harbored apocalyptic potential. This study contributes to the anthropological literature on the relationship of time to natural resources (Limbert; Ferry and Limbert) by examining how materiality structures the temporality of crisis. The social history of anxieties of “ruination” (Stoler) in Egypt reveals narratives about the Middle East and environmentalism that have remained marginalized in studies of the Cold War (Hecht; McNeill/Unger; Lee).