This is interesting.
Alcoa has drawn opposition to its power generating plant on the Yadkin River based on a water scarcity/economic development argument. I think. Seems to me if we are worried that Alcoa is getting a free ride, we need to make sure we charge enough for the water the company uses.
Incidentally, making aluminum requires enormous amounts of electricity, which is doubtless why Alcoa built its own generating plant 50 years ago.