The present invention relates to a retractable floodwall unit that comprises a foundation unit having a plurality of guide tracks along side walls of the foundation unit, a floodwall panel stowed in the foundation unit; a power system for raising and lowering the floodwall panel, and a plumbing system. The plumbing system is configured to remove ground water from a dry-side of the floodwall unit and flood water that becomes located in the floodwall unit.