Another thing you can do to prevent some windblown leaves from entering the pond is to put in some fence upwind. This will allow the majority of leaves to drift up along the back of the fence rather than entering the pond. If you have a lot of rocks, you can build a relatively tall stone wall, 4ft or so upwind from the pond to serve the same function, only much more attractive.
Bill C is giving some great advice! Thanks Bill.
I didn't build my pond originally for swimming, but it has become a great swimming hole mostly due to dumb luck.
From your pictures it looks as if the rock dock is too low? Remember bare feet as well, so a smooth surface would be nice. Also a steep drop on the very end for jumping/diving or ability to place a ladder. I found an aluminum 5-step dock ladder worked pretty well in my pond as it conducts heat from the lower warm water to the surface which except on the coldest days kept the ice off of it. Our ponds are too small to have ice heave the docks and ladders.
Whirlygigs do bite by the way, they are devious little jerks. Usually they nip when you are working on something and both hands are busy and cannot shoo them away. Painful bite, and they latch on! I may have to toss in a single SMB if they eat the whirlygigs. Nothing else seems to, I have thousands of them.
