RedactedNarrative: Unit 1 was traveling South on Black River towards Georgetown after leaving the sand bar area. It was approximately 9:00 o'clock pm and was dark. Operator stated that he was using his GPS to navigate after dark and not keeping a proper lookout. Operator stated that the GPS started to “lock up” and as he was trying to correct this problem Unit 1 struck a piling on the edge of Black River while still traveling on plane. Unit 1 made impact on the starboard side of the vessel about halfway down. Operator did not notify SCDNR until approximately 5:30 PM the next day.