I would suggest the upper 6 feet or so. I think relatively few ponds in Ohio lose the multiple feet of depth due to dry conditions common to Texas and other areas (based on my experience of an 8" maximum depth loss in the Summer). But you can find what is probably better advice than that in several threads in this section on placing cover/structure.

I strongly advise you to take careful note of where you put it (lots of pictures are great), especially since you plan on swimming in the pond. All the structure in our pond with the exception of four rock piles (which are so deep they may not be effective as structure, but are too far down to interfere with surface swimming) are in a "no swimming" zone marked off by a floating polypropylene rope. So we don't have to worry about getting hung up in Christmas trees or whatever while swimming.


"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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