My most time on the water crappie fishing was on a 500 acre reservoir. We would sometimes catch crappie in the "fluffier" structure along the banks, and also trolling crank baits as we crossed open water moving from one side of the lake to the other side (to continue bass fishing).
However, by far the best crappie fishing was always on two huge brush piles. These consisted of large trees with just the trunks and main branches, and cabled together so they didn't float off after the initial placement before the lake filled.
They were in deep water (one in about 16', one in about 23'), and were basically like very large cribs. At normal pool, the tops to the main branches came to within about 5' of the surface.
Protocol was to first throw jigs over the TOP of the brush piles. On good days, that would catch a lot of crappie. The next step was to let your jig get deeper than 5' and try to bounce off the branches to get the crappie. This also resulted in good catch rates, when you didn't get snagged.
Many times, the first two steps would only produce crappie the size of your hand. Other springs, it would produce lots of 10+ inch crappie (and we ate like kings)! Rarely, it would produce good-sized crappie plus a few real whoppers.
The third step was always to run jigs deeper along the outside edges of the brush pile to try to induce crappie to strike that were in deeper water. We did catch a few, but I NEVER had the experience of catching little crappie at the top and bigger crappie from the deeper water. Nor did I ever have the experience of only catching crappie from the deeper water. The top of the pile, and the 5-10' depth within the pile was always the most productive.
(Interestingly, if you did get a jig near the bottom along the deep brush, we would sometimes catch several spotted bass.)
In my (very limited) experience, I don't think the deep water aspect made the brush piles productive. I believe it was the awesome crib created by the structure that really concentrated the crappie immediately after the spawn and through the summer months.
My other non-expert advice, is that every lake is unique. I would try for two brush piles (or cribs) at slightly different depths this year. Make sure to fish both on the same day in the future so you have a fair comparison between the two. Determine which one is consistently more productive, and then copy those conditions on your future projects.
Have fun managing your pond this year!
