When I first 'cut my teeth' river rafting, my instructors talked about a collection of 'river gods'.  They were not referring to the bold whitewater enthusiasts who were starting to push the boundaries of river rafting all over the planet while claiming first descents, though many thought of those daring adventurers as 'river gods'.  It was their way of introducing the green river runners in our party to their version of the mythological pantheon of 'river gods' that they claimed were part and parcel of a free-flowing river.