I dunno that it's a good idea. What would the US be willing to pay for that water? I mean if it's like the pittance water bottlers have been paying, fuck that.
Would we have restrictions on usage, and limits on how much they can take per year? Like there's a large chunk of desert that's growing crops and takes a LOT of water.
Lots of questions to be answered and logistics to look at first.
Why not? It's a free trade agreement and Canada has known for a long time that America would be looking at our freshwater sources because of their mismanagement.
I don't think you can just look at some old oil pipeline and just decide to run freshwater through it. Pretty sure water isn't the same as oil also I don't think most people want to drink oily water.