The shad are on the bottom and the current is swift on the James River. In order to coax them up, local anglers are still using a ½ oz weight, but a better color selection for this part of the week would be pink/white or chartreuse/white. The same colors go well for the fly-fishing crowd, but getting down to the fish is a bit more involved. A sink tip will not do it at the moment. A full sink line over 300 grains is more likely to dredge them up, and even then seek out calmer waters to probe with your fly. A short leader of untapered fluorocarbon is better than monofilament to get the fly down to the fish, say 4 feet of 10 or 12 lb.
If you do not find the fish at first, keep moving until you do. Once you get the bite, stay where you are and explore the area thoroughly.