The forces of wind and wave have been creating and destroying the beaches throughout time. The tide acts as a constant force affecting the form of the beach. As the sea and the wind move, the beaches move. Where the beach can t flatten, the waves carry the sand to deeper elevations in the ocean. The sand is continually carried off, making the ocean floor larger and the beach itself smaller.
Erosion can also occur as a result of human influences.
Structures that may serve a purpose to calm waters in harbors, store water, control flooding, and allow boating navigation may trap sand that would normally be deposited on a beach.