the sculptures are surprisingly large. in some cases weeks of effort by a team of people go into making them. very impressive stuff.
I think the competition is less than 10 years old. the beach sand itself isn't much older than that. the sand that is there now was trucked in. when I was a kid the beaches there were course gravel. (what do you expect in a mountain valley where there are no tides?) there's a large pond next to the lake that is man made too. even for all that Harrison is a very picturesque place. lots of retirees and tourists in the summer.