[Scott Christensen]

Scott Christensen asked the Naked Scientists:
   
Hi,
I have a science question...sand is heavier than water, and the waves
at the beach create an undertow, so why isn't all the sand at a beach
washed away?

What do you think?

[litespeed]

Interesting Question!  First, in several American Beach Resort areas it IS washed away, and is constantly renued at some expense through sand replenishment schemes of one sort or another.  These have been routine for many decades.

However, some beaches are renued through natural processes or replenishment. Some beach sand is from local coral reef sources, others from natural erosion from inland sources.

But your point is well taken.

[litespeed]

DD

Good post.