RedactedNarrative: Operator of vessel 1 was motoring away from a rig after night fishing. Vessel 1 contained the operator and 1 other passenger. The operator said that he was idling in forward at an estimated speed of approximately 3-5 mph. Unexpectedly, he felt his vessel being pushed against his control toward his left. The operator looked at the water to see if he could tell what just happened. The operator could see a partial piece of pipe, with flange on it sticking out of the water in between 2-4 feet seas. 
  
  It is believed by the operator that this pipe is normally below the water's surface. The operator said that this pipe was unlit, unmarked, and he had no prior knowledge of it being there. The operator said that if the submerged pipe was marked with a light or buoy, he would have never made contact with it. Vessel 1 is 37 foot catamaran style boat. There is pretty heavy fiberglass gel-coat scratching and gouges on approximately 14 feet of the starboard side of vessel 1. There were no injuries due to the very slow speed of travel of the vessel. Neither alcohol nor drugs were perceived to be a factor. PFD's were worn by the occupants of vessel 1.