.....Longshore drift is caused by wave and current action. It is the primary method of sediment transport along the beach. The direction of this motion is always parallel to the beach face. On Folly Beach, as well as other islands along the southeastern coast, the lonshore drift most often moves in a north to south direction. This occurs because most of the wave hit the beach at an angle. In the picture below notice how the waves are approaching the beach at an angle. The yellow line represents the angle of the approaching waves. The orange arrow shows the direction of the longshore current.

Click here to see animation of the lonshore drift process.