Anyways, we were out on Lake Roosevelt this past weekend and these were all over. The level of Roosevelt is higher than it has ever been in it's history, with the new dam and all.
Yes that is a full grown saguaro cactus... Probably 15' of it under water

Can you imagine someone diving off of a boat and hitting one of these that is hidden a few feet under water? Or a water skier hitting one that has broken off and is floating out in the lake?