Make sure your nymph box has some san juan, prince, and of course the usual suspects (hares ear, pheasant tail). I would also throw an egg or two as there are other species in the tailwater that will initiate their spawn in the coming weeks. If the water is low, make sure to switch from a thingama-slapper bobber to a more realistic soft indicator like a larger dry fly for a better presentation. Make sure to bring your midge patterns for the late morning hatch. I do not know if the BWO will be out quite yet, but I would always have an emerged or dry for this. I like these two flies in size 18,20, and 22.
Streamer fishing, I would focus on the white and olive sculpin or baitfish patterns. My favorite size is a 2-3 inch fly either stripped through a seam or a nice soft swing through a downstream hold.
Keep on the watch for water flows depending on the snow melt and the potential rain. You can always call the fly shop at 937-434-8472 and we can help project your forecast for you.
Good luck. Cheers!