This dissertation follows sea-level rise related flooding in the South Carolina Lowcountry as a way to explore enduring material afterlives of slavery and racialization of hydrology. The Lowcountry is a region that was produced by slavery and the extraction of tidal power together. 40% of enslaved Africans arrived in the United States through ports in Charleston, South Carolina, many of whom were forced to engineer monumental tidal rice plantations, which generated foundational wealth for the region’s planters and determined property development on marshy low-lying lands. Today, increasing sea-levels and consecutive tropical events have led to monthly nuisance flooding and periodic disastrous inundation, transforming this once-profitable tidal relationship into a publicly acknowledged emergency. However, in the resultant crisis discourse, protection is guided by a tradition of white heritage preservation and materializes in the racially uneven creation and maintenance of coastal infrastructure. To explore the relationship between white heritage preservation and water management, I track the tidal flow of water through historical, contemporary, and future coastal infrastructures, moving across urban, suburban, and rural spaces, as well as wildlife preserves on former rice plantations. Each chapter examines one interaction between rising waters and the continually changing coastal landscape, revealing the complex and often counter-intuitive ways race becomes embedded in geomorphological processes. Connecting the history of racially motivated wetland reclamation for property creation and rice plantation cultivation with contemporary projects adding drainage to gentrifying communities, I argue that water management in the Lowcountry can be understood as a racial project pairing whiteness and drainage. I subsequently observe how this process is perpetuated in future megaprojects for “perimeter protection,” “fill and build” development practices, and even drainage projects claimed to address environmental justice, all of which aim to create value by protecting areas deemed worthy of protection while displacing water to predominantly Black areas considered less valuable. I consider these and other efforts to be shaped by the legacy of the plantation as a system of both environmental simplification and antiblack racial dispossession that nonetheless afford for futures beyond its logics. I offer racial hydrologies as a concept to depict how hydrological processes become entangled with projects of racial formation without being fully determined by them. Racial hydrologies are the result of the process of organizing hydrological systems around durable racial hierarchies to extract value, maintain property regimes, and solidify social difference. However, such hydrologies are never final, and as I outline, they undergo continual changes as coastlines sediment and erode, and activists contest racialized control over space.