Abstract: The hull has a pair of laterally spaced pontoons which are rigidly interconnected by beams which extend between them at a level low enough that a barge will float over them. An elevator with a lifting and lowering mechanism is mounted on the hull with sling or cradle-like lifting bars. The lifting bars have upstanding posts which are shaped, sized and spaced to fit in the stacking post sockets conventionally provided in the hull bottoms of LASH barges. In a lower condition of the elevator, a barge will float over the bars. In a raised condition of the elevator, workers may stand on the hull pontoon decks and work on the sides of the barge and work on the bottom of the barge from scaffolding hanging under the lifting bars. For working on conventional river barges (which are longer than LASH barges) the lifting devices may be used in pairs.