Welcome to the site & this wonderful sport!
Both of those rivers are known for LM bass. There are also Striped bass in the lower sections of the James. The upper areas of the James, as cuffer has said is good for Smallmouths. Some type of watercraft would help increase your chances if you have it available. Even a belly boat.
I live up in MD & have not fished in those areas, but know of others who do.
Depending on the weight rod you have, try larger streamer patterns, and poppers, at least a size 2 for the LM bass. Something in the 3 to 5" length range for the streamers if your rod is heavy enough. Smaller flies are fine too & have there use.
Go with heavier leaders & tippets too, again depending on your rod. I've fished for bass with anything from a 6 wt to a 10 wt, and 10lb test tippet is about the minimum I'll use with the lighter rods. Typical leaders & tippets used for trout or panfishing are usually not best for the bigger flies used when fishing for bass.
There are many fly patterns that are good for bass. Lefty's Deceivers, Seaducers, and various rabbit strip flies are some I've had good success with for both SM & LM bass. Same flies can be good for Stripers.
In tidal areas, it's usually best to fish during those times when the tides are moving. Tidal currents limit baitfish movements & often concentrate them in small areas, so that's where the bass will be. Think in terms of structure, cover & current. Where you find these in combination you'll often find the bass.
Hope this helps you some!