The water temp. is very important, unless the water is quite a bit warmer at the discharge those fish would be wintering down river where the water is slower. Winter bass don't move much and congrigate in a small area where they won't have to exert any energy. If there is bass near the discharge look for eddy's where the water is moving back upstream and try dead sticking tubes, small grubs, and 4" senkos and finesse worms. Try split shotting and carolina rigging these baits also.. I'm jealous we have a foot and a half of ice and all we catch now is walleye, perch, and pike but at least they taste good.