Large-capacity riverbank filtration (RBF) facilities often require large amounts of river frontage, exposing the facility to increased security risks. The design of the 230,000 m3/day RBF facility at Louisville involved construction of four radial collector wells along 2,000 m of riverbank, much of which was not owned by the utility. Concerns regarding the security of the facility were addressed by constructing the riverside portion of the facility entirely underground, with a single pump station located within the fenced perimeter of the water treatment plant. This chapter describes the unique design features of the facility, including sub-grade collector wells, connection to a hard-rock tunnel, and the pump station.