Information he presented is kinda obvious and yet non-straightforward and I would unlikely to ever realize it when under the pressure of being in "a bind". Anyways, I thought you guys may find this useful or simply interesting...
Why?
Apparently majority of fatalities come from the fact that people (after slipping into a hole, or sand shifted and gave away, or swept by current) stay upright for too long trying to regain ground -- thus losing air from waders (it gets replaced by water rushing over the edge of waders). This is an instinctive reaction and by the time it becomes clear that it isn't going to work (i.e. for whatever reason you can't "walk back" using your feet) -- it is too late, waders are full and now you are in a real trouble.
What to do?
According to that guy correct thing to do is immediately bring your knees to your chest -- basically, you are supposed to end up floating on your back with your face and your feet on surface and your butt pointing down. Air in your waders will accumulate in your boots and calf area and will provide enough buoyancy to keep your lower body floating; air in lungs/etc should keep upper part afloat. Now you use your arms to paddle yourself to shallows and stand up ONLY if you know it is safe and shallow.
So, basically main trick is to avoid doing stuff that causes you to lose air in waders.
Additional notes
- if forced to swim on your belly (for whatever reason) -- keep legs bent at the knee with feet pointing up (to keep air pockets at the end of waders intact) and swim in brass style. Swimming using breast strokes will cause your legs to go down, lose air and tire you too fast. Butterfly isn't a good idea either.
- Neoprene waders are better in that sense -- they retain some air in material even if completely flooded
- last resort is to try to take waders off -- advice was not to try it unless you've done it before or are desperate. Proper way of doing it is to "roll it off of you" as opposed to getting out of it (which would be hard due to negative pressure created by your actions).
- he really insisted on everyone actually trying this in controlled environment, so that you are familiar with situation, know what to expect, don't panic (and do stupid stuff) when this actually happens
