RedactedNarrative: Operator stated his vessel began taking on water for an unknown reason. Initially his bilge pump could not keep up with the water flowing into the vessel. As the vessel filled with water, the battery became submerged and caused an electrical system failure. The vessel became partially submerged and the operator and passengers abandoned the vessel. An unknown boater picked up the operator and his passengers from the water and towed the partially submerged vessel to robinson landing boat ramp. The vessel was upside down when it reached the ramp causing the contents of the vessel to be lost while towing - most notably approx $500 in fishing equipment. The lawton pd and fd assisted in flipping the vessel upright and helped the operator load the vessel onto his trailer. It was later determined that a fitting on the transom had possibly failed causing water to leak into the boat. Area of the accident was southeast of the robinson landing jetty.o