As a shamed expert, there is a lot of good info here. A couple of things:

-If the water is really THAT bad, a helmet is probably wise. On a related note, you could bruise/break other body parts that might limit your mobility after the incident. My last time, I ended up with a softball size bruise on my [Bleeeeep!]/upperleg that made me walk funny for a week.

-Wading belts are really the key. If you really want to go overboard, you could wear 1 near the waist, 1 near the chest, and 1 for each upper thigh.

-Fully zipped up coat and cinched down coat.

-I'd give each guy a throw rope to keep on them. You can use it to save the other guy or use it yourself from wherever you wash up (which may not be a good spot and may require additional swimming to get you to a safe place).

-Protected cell phone if you get service where you are going.

Good luck. Stay safe. [Bleeeeep!] gets scary in a big hurry.

-AP