The Last Descent

I stumbled upon an article in Kayak Session about this video being made called The Last Descent. It is basically about the damming of rivers as these people paddle rivers that are in the process of being dammed or will be soon. It raises the question of what is worth more, keeping the rivers intact as they are or harnessing their energy and changing them drastically. Also the people displaced that rely on the river are something to consider. Anyways, look around at the movie's website and watch the trailer. Comment with your opinions on the topic. In today's world we need an alternative energy source, but are these things worth giving up for it?