A marine pier system employing a payload transport device for transporting persons and material from land to marine craft moored at a distal end of the pier. The payload transport is a movable deck having an electric motor powered by batteries for use in moving the deck and persons/material placed on the deck. The payload transport device is self-contained allowing freedom of movement along a support system eliminating the necessity for decking along the length of the pier. The absence of decking provides a structure upon which wind and wave action and deterioration from sunlight and weathering has little destructive effect, and further allows sunlight to reach the aquatic life below the surface of the water. The movable transport device further permits sunlight to reach all areas of sea grass that are shaded by movement of the transport device to a non-sensitive area when not in use.