You are in the right direction. Dams are good. They really are a lot like walleyes in a way. Don't tell this to walleye fanatics or you will get scolded for saying something like that. But anyway, find yourself an eddy around the dam, or a hole in the river with downed trees or in your case ROCKS! They love to sit in deep water behind current breaks. In June they spawn, often easy to catch, nightcrawlers may work if other fish don't get it first. Take a big minnow, cut the head and tail off, or a sucker and cut the back out, three to five inch long by one inch square piece of sucker. leave the skin on and put the hook through the skin. This is cut bait. Good stuff most of the time. Let it sit in that eddy or above a snag in deep water. You won't believe how well they smell the oil in the bait, just keep the bait fresh! change bait every ten minutes or so. Later on you might want to try stink bait. That's another story for later on in the year like July and August. Later! Oh yah a heavy rod and reel, 14 to 17 pound test.