A base for a data storage system is provided having an inner facing surface and an outer facing surface. The base includes a motor well. Formed with inner surface of facing surface of the base includes a medium region, an actuator region and a dam. The medium region is defined by a medium region planar surface surrounding a portion of the motor well, a leading surface and a trailing surface. The actuator region is defined by an actuator region planar surface that is recessed from the medium region planar surface, the leading surface, the trailing surface and a remaining portion of the motor well. The dam has a dam planar surface that surrounds the remaining portion of the motor well and is positioned on the actuator region planar surface between the leading surface and the trailing surface.