A household dishwasher includes a washing container receiving a dishwasher load, a pump pot, and a spray arm for applying washing liquor and/or fresh water to the dishwasher load in the washing container. The spray arm is actively driven by a drive system and mounted on the pump pot for rotation about an axis of rotation. The spray arm has a rib geometry that revolves around the axis of rotation and includes an encoding groove running along the axis of rotation. The pump pot includes an encoding rib running along the axis of rotation and corresponding to the encoding groove. The encoding rib is configured for passage through the encoding groove along the axis of rotation during assembly and disassembly of the spray arm so as to enable the spray arm to be assembled on and disassembled from the pump pot in precisely one angular position.