Drain pump assembly for a dishwasher appliance

A dishwasher appliance is provided having a drain pump assembly including a hub mounted to a drive shaft that is driven in a first direction during a drain cycle and in a second direction during a wash/rinse cycle. One or more vanes are mounted to the hub and are rotatable between a retracted position during the drain cycle and an extended position during the wash/rinse cycle. A biasing member is mounted to each vane for urging the vanes to the retracted position to counteract the centrifugal force exerted on the vanes during operation. In this manner, the drain pump assembly pumps wash fluid during a drain cycle but does not pump wash fluid during a wash cycle.