At low tide if the trough is shallow and you can walk in it, have a look to the ripples. Ripples do occur if there are waves. Their direction is influenced by the wave direction, which in turn is influenced by the current direction. In case of a long symmetrically shaped sandbar the ripples will be paralel to the sand bar. In case of a current, for example a feeder or neck current the ripples wil have a different shape and direction. So at low tide you can get an idea what is happening at high tide in the water.
A different phoneme are the holes. In case of a wind driven longshore current for a longer period holes are developing in the sand-bars, beaches and rips. Bathing people can be negatively surprised if they step suddenly in a hole.