For a self-powered marine lifting vessel or catamaran having static buoyancy, a working deck is forcibly raised or lowered by flexing or extending each of a plurality of articulated pairs of fixedly mounted support beams connecting each hull and the deck. One version uses locally applied forces at the joints from adjacent hydraulic cylinders, incidentally causing the hulls to rotate about their axes. Another version forces the hulls to rotate axially from a non-rotating aft inter-hull linkage. Applications include routine harbor maintenance and hull cleaning, then emergency marine pollution including oil cleanup at a polluted site.

For a self-powered marine lifting vessel or catamaran having static buoyancy, a working deck is forcibly raised or lowered by flexing or extending each of a plurality of articulated pairs of fixedly mounted support beams connecting each hull and the deck. One version uses locally applied forces at the joints from adjacent hydraulic cylinders, incidentally causing the hulls to rotate about their axes. Another version forces the hulls to rotate axially from a non-rotating aft inter-hull linkage. Applications include routine harbor maintenance and hull cleaning, then emergency marine pollution including oil cleanup at a polluted site.

A floatable barge, deployment system, and method of use. The work barge and dump barge are operable to be directly loaded from the water and deployed into the water from a roll off truck. The barges include a top deck supported by a hull with a mounting assembly that is operable to engage a deployment mechanism of a roll off truck. Optionally, the work barge may include retractable pontoons that rotate from a folded position to an open position, and the dump barge may include a permeable barrier. Both barges are configured to be transported on roadways and interstate commerce via a roll off truck.