I've never boated WW at 10K...
But I swam most of it at that level once! I remember getting pulled under despite a Type V PFD with 25 lbs floatation, spun around in the vortices, and seeing it get lighter and lighter as I got close to the surface, then get darker again as I got sucked down before getting a gulp of air.
have a good trip, Patty,
Nothing in the world is more yielding and gentle than water. Yet it has no equal for conquering the resistant and tough. The flexible can overcome the unbending; the soft can overcome the hard. - Lao Tse