Though it seems very legit in real-life, storing bins of items, satchels of coins, bags of goodies and whatnot at the bottom of the river by hiding them there is something we frown upon in-game. The river current picked up a bit tonight while I was swimming the length of The River With No Name and most everything was swept away. Unfortunately I could save very little, and those things I could save went unclaimed for five minutes, so I'm keeping them.
Carry on.