The same thing happened in a local pond built last year and they did something a little different. I don't know how the equipment operator did it, but he was able to stack several of these large rocks in a vertical column - mostly a one rock wide column one on top of the other - in about 12 feet of water so that they just about exactly reached the water line when it filled up. Maybe this isn't the best structure, but it's in an open area of the pond and I know from experience in local lakes and rivers that fish will hold very tight to the shady side of any bridge support column I find. I think this would be even better.

What do you guys think?