thank you all for your suggestions. billabong was my own thought, except it is part of a river which has been left behind as a lake. bushwhack is really an American term, but I will give them both thought.
Have found the expression "Boomerang burn" which was popularised in an Australian tv show in the 70's. It means to return an insult already thrown at you.
But I like AB's answer as a burn is a branch of a river.