If I understand GregDavis' proposal above, he wants to have a floating cable mainline, and individually anchored skier buoys? If so, then I would second that. I do respect his opinion either way as he is a verteran course installer. If the thought is to put all 26 anchors in individually, this is a method I would only recommend on a drained private lake.
I put many courses in the Great Miami River over the years, and the biggest headaches came with the individually anchored course. The individual anchors (2'x2'x6" concrete with rebar) almost always had something caught on them, were constantly washed downstream by trees when the water was high, and were a pain to place and move. We fooled with various subfloats and counter balances. The best river course design we came up with was a high quality mainline with lots of tension and lots of weight at each end. I think our last slalom course mainline anchors were over 1000 pounds upstream and 800 pounds downstream with enough tension that you could walk on the mainline from boat guide to boat guide. Then we individually anchored the skier buoys using tires filled with concrete and rebar stakes through them. Subfloats were at 4' depth, and had light bungee line to the skier buoy that would break away easily when the fishermen tried to pull it out of place. I will admit though, our Great Miami River site has more current, more flow, and more trash than either of your two pools on the Scioto. 10' of rise and enough current to trick ski with a rope tied to a post was not uncommon for our site after overnight rains up north.
I have the survey equipment and have placed many courses in private lakes as well. There is no greater value than a well engineered, high quality, floating course from EZ slalom. Period. There is no reason that with the right anchors, tension on the mainline, and river current adapters, your floating course can not be made accurate. I wish I had his products to work with in the early 90's when we fought that river year in and year out. At the very least, use one of his heavy duty mainlines, then individually anchor the skier buoys to elimiante current and wind problems.
As far as permits go, I always think it is better to ask forgiveness than permission. As of right now, in Ohio, your permit would have to go through the local authority (presumably Columbus). However, in the near future, all courses in the state (public water OR private lakes) may have to be permitted through the ODNR. Proposed legislation is still pending on that.
Best of luck,
Lottawatta