To prevent freezing at a low temperature by nearly completely sucking water on a parking palette P by vacuum, and also to save power.

The drain apparatus 1 of a parking palette comprises a suction head 11 that comes into contact with a parking pallet P at a usage position U1 for sucking water being present on the parking pallet P by vacuum, a turning arm 15 that supports the suction head 11 and is supported by a bearing 16 being provided outside the parking pallet P so that the turning arm 15 can turn between the upper usage position U1 and a non-usage position U2 where the suction head is separated from the parking palette P, a flexible pipe 21 that is supported by the turning arm 15, follows the turning of the turning arm 15, and transfers vacuum to the suction head 11, a vacuum tank 40 where the flexible pipe 21 is connected to receive the sucked water, and a turning drive apparatus 30 for turning and driving the turning arm 15 between the use position U1 and the non-use position U2.