Ron,
maybe somehow you were misled into believing that I meant filling in the pool with rock & sand to the level of the drain at the bottom of the dam, and that's not what I was referring to. Just to fill in the void at the bottom of the pool, nothing more.
I did mention though , it would be nice to be able to stand at the side of the pool that is too deep. Filling in the void with a little rock and sand wouldn't affect much.
Again, I am not suggesting anything here.