The placement of these can be often up to a flip of a coin.

There are elements of man and nature here, so either would work. We don't get enough City, Industrial images posted, so it's nice to have this one in here.
Great captures on both. I think with one being wide and one being tighter, I can't pick between them. I like seeing the how big that dam and spillway is. And having the fall colors scattered around it's really fun. The tighter image is also pretty cool to see more of the details.
Don't forget, these will qualify for Alan's Waterfall Wednesday weekly thread, so save an image or two for there.