An automatic bilge drainage pump of centrifugal type is designed to remove water from the hold and the inter-deck space. The pump determines the presence of water by the current consumed by the engine. In automatic mode, the pump turns on every 15 minutes. If there is water in the hold and the engine is running with a load, the pump will continue to work until the water is pumped out. If there is no water and the engine is running without load, the pump will automatically shut down after a fraction of a second. The lower part of the pump body is a removable coarse filter that protects the working impeller of the pump from damage.