For rivers, I would have thought "dry" in Australian folksong, though I can't think of any just now.

Several NZ references to the "dry" Cardrona River (sp?).

"Sweet" Thames Flow Softly. And can I recall a reference to the "Sweet" Liffy Water? (Don't think I would care to *taste* either of them!)

"Wet"? No, unless there's a song about the previous guest contributor.... (Am I allowed to say that?)