"Damnation" is a term derived from the Latin damnum, meaning "injury" and "loss," and often connotes deprivation of what should have been possessed. Just as there are varying degrees and types of salvation, coupled with eternal progression in some areas (D&C 76:96-98;131:1-4), so are there varying degrees and types of damnation. In LDS doctrine, to be damned means to be stopped, blocked, or limited in one's progress. ("Damnation", Holzapfel, Richard Neitzel, The Encyclopedia of Mormonism, 1992)I am not sure how a water damn relates to it. There is so much power here in symbols. A water damn literally holds back water. Water is a symbol of life. Life as we know it on earth requires water. Jesus is spoken of as being the living waters. To be damned is to be stopped in our progression. It is to have withheld from us the living waters.
What does the living waters do for us? It allows us to grow, to become more that we were. To live and if we are willing, to evolve.
Who damns us? I suggest that we damn ourselves. The only one holding ourselves back from more living more life. More growth and joy and freedom and power to be whatever good we want to be, is us. Now it is possible to not be aware of our own damning choices. We can have the results of damnation because it is how surviving is modeled to us. We learn it from our parents or society. We can be damned because of our neighbors.
We are free from damnation by first becoming aware that there is an escape. Jesus is that escape. he demonstrated that we need not be limited by our self-destructive behavior. Our limited way of being. He showed us and by so doing, gave us hope and faith that we might be and do as he did.