Abstract: A drainage device, system, and method for draining moisture at a wall adjacent to and projecting from a floor is provided. An elongated body extends arcuately above the floor and is attached to the floor to define a channel between the elongated body and the floor for receiving moisture from proximate the wall at a rearward end of the elongated body. A barrier is proximate the wall and defines an opening to the wall adjacent to the floor that is dimensioned complementarily to the elongated body for receiving the elongated body therein. A rear flange at the rearward end is dimensioned to be captively received between the wall and a barrier via the opening for allowing the moisture between the barrier and the wall to drain into the channel via the rearward end. A sealant seals the rear flange to the barrier.