Abstract: An apparatus is disclosed for a cover assembly where the assembly includes an elongated body having first and second opening defining edges which define an elongated opening within the body. A covering material is provided sized to cover the opening with a first edge of the material attached to the body and a second edge of the material attached to an elongated bar. The apparatus includes a motor for selectively rotating the bar about the axis in first and second rotational directions to wind and unwind material from the bar. A tensioning mechanism is provided for urging the bar member to move in a direction with the bar member and tarp covering the opening.