Thanks Gary, man I wish I had a bigger tractor like yours, I'd like to start "haying" but I might have to upgrade first. You definitely have alot more rocks than I do, but I think it's just because this used to be farm land, and they already removed most of the rocks. I agree with you on the banks of the pond. I'm wondering where the high spots are going to be also. I'm planning to add an overflow drain out of the back, when I get to it. As for the "kidney" shape, I originally planned it as an oval, but the trees kinda forced me to shape it that way when I made it bigger. I'm glad now because it looks pretty cool. Here's a pic of the larger dirt pile that I took out of the pond. The other pile is about 1/2 this size.
Take a look at the pond photo of mine and in the one with it full of water to the lower right hand corner is where I let out the overflow. I was going to put in a pipe like you on the lower end, but before I got around to doing it, it overflowed and I was out of the country so my brother in law just used his front in loader and cut the side of the levee on the upper end to let the water out so it wouldnt wash away my lower end dam. He had made a pond per Arkansas Soil Conservation specs and that was what they required. NO pipe as they said it couldnt be sized to take care of unexpected rain fall. They require a spill way put in on the UPPER end where water enters and then directed around the perimeter beyond the dam walls. It works very well and is easy to put in, just cut a trench around the ponds upper dam walls. Its real easy to find the right depth when the pond is overflowing, just cut it a few inches below where the water starts to run out. You might need some rip rap in the sluiceway to keep down erosion. I put some rocks in mine where it runs thru the dam wall so it doesnt wash out any deeper and then the grass takes care of the rest of the fall back to a creek about 30 feet behind the back of the pond. You could do the same for yours and forget about a pipe overflow.