Phoenix (and many other cities) get a lot of their energy from dams along the Colorado River, but I would totally favor dismantling all the dams and letting the water run its natural course, once again, to the sea.
Although they have been key to the progress of humans, restrictions on nature just bother me -- like damming a river or erecting levees to create an unnatural river course. It is probably too late now, but I really wish humans had evolved to live alongside nature, not tear it apart and destroy it just for a few moments of profit. Maybe, slowly, humans are beginning to realize the importance of working with -- not against -- nature. I guess we cannot undo hundreds of years of damage, but maybe we can slowly work to bring back the natural course of things.
An article in our local daily reports on plans to start allowing regular floods down the Colorado River -- naturally occurring events that were stopped by the building of the Glen Canyon dam in 1966. Over the decades, this lack of flooding has damaged habitat and endangered wildlife. By creating occasional artificial floods, we might be able to correct some of the damage that has been done.
You can read more about the new plans here.