Described are a vessel and vessel/barge systems for dredging underwater surfaces. The vessel includes a hull with a bottom, bow portion, stern portion, port side, and starboard side. The vessel also includes a deck supported by the hull and a pump system mounted within the hull. A drag arm pivotably couples to the pump system. The vessel additionally includes a void defined by contiguous watertight walls or bulkheads joined to and extending upward from the bottom of the hull. The contiguous watertight walls or bulkheads are (i) vertically extensive of a perimeters of an aperture in the bottom of the hull, (ii) outboard, astern, and forward the aperture, or (iii) some combination thereof. The barge is releasably coupled to the vessel. Moreover, the barge is in fluidic communication with the drag arm.