It will be difficult to cast to them in that kind of water and not spook them. You would almost want to cast where there was not a fish, And wait til one comes around that area. Then strip your trusty wolly bugger across the bottom. Or cast well above them if there is enough current to carry it down. I would start with a white Bead head WB. That way you will be able to see your fly and any fish that might be interested. Good Luck !
Brother Rich will chime in I am sure and give you the deadly formula for Bass! I have never landed a Bass on a FR. But The WB is very versatile ! It should do the trick ???
Let us know how it works out !