The Coast Guard received noticed that a 50-ft Sea Ray and 310-ft barge collided. The recreational vessel was enroute to Savannah for a St Patrick's Day celebration from Sunset Beach, NC.  The commercial boat was under contract from the USACE to dredge.  Two recreational vessels crossed the dredge that h ad just finished operations.  The second changed directions and hit the dredge.  Prior to the collision, the dredge had sounded the danger signal and had reversed propulsion. While the Sea Ray was not taking on water, it had significant damage to the top.  The Coast Guard escorted the Sea Ray.