I would think that the BC residents have enough on their plate. The WAC Bennett Dam was completed in 1968. It must have taken a good number of years to build. At this point in time the environmental movement was just getting off the ground and going back to that period many of us were just beginning to realize that our modern society had so many flaws. Just a quick look on the internet mentions that this dam is being impacted by the Site C dam which the people of BC have been fighting. Dams are not generally considered environmentally friendly. I did not look at it's impact on Alberta but if that is the case as you say, then maybe Albert should start looking at forming a strong environmental movement. My impression is that Albertans are more than willing to plow the environment under for short term economic gain, one example of this their desire to export beef which requires a lot of water.
BC residents have every right to protect their coasts and they have some very dangerous waters.