This is really well done and it may be even more timely today, after we've seen Hurricane Katrina and "An Inconvenient Truth." These things are all related, and this documentary examines the threats posed by our lust to develop areas that are unsuitable for development. We hear a lot about peak oil and the impending scarcity of oil resources, but less about how scarce water is becoming in this world. This doc examines that situation thoroughly and does a good job explaining how we got here, and what drove us to build so many dams in the early 20th century. Plus it's got a great interview with Robert Towne, who wrote the screenplay for "Chinatown," the plot of which includes some intrigue around (stolen) water rights. The book this is based on is a good read and the author who has since died is interviewed at length in the film. It's really great stuff here.