Open mud barge is longitudinally symmetrical composition of two and a half hull, the two halves of the hull were about two hinge axes of rotation. When dredging silt it carries, its total weight is the total weight of the two half empty pods plus the weight of the sediment contained in the hopper. Location of hemi sediment’s center of gravity, located at the inside of the hemi-hull’s floating heart, is more near to the longitudinal midship section of the barge compared to the floating heart, and thus produce a flared moment for the hull. The on and off hydraulic cylinders of the hull are to conquer the moment, so that the hull remains closed until the ship has traveled to a predetermined area, then the hydraulic cylinders works, so the hull begin to throw mud under the action of opening and closing hydraulic cylinders and its flared moment moments. After throwing mud ,the barge lose weight that mud contained, then the two halves of the hull reclosed by tension of the hydraulic cylinder.