STEVE INSKEEP, host:
To better understand what it might mean when a lake like Lake Powell goes down, it helps to understand where the water is going. And to understand the water network surrounding it and how it developed, we've brought it Charles Wilkinson. He is an authority on natural resources law and teaches at the University of Colorado at Boulder.
Welcome to the program.
Professor CHARLES WILKINSON (University of Colorado): Good morning.
INSKEEP: Can you just explain the original purpose of Lake Powell?
Prof. WILKINSON: Well, the Colorado River is the largest river in the Southwest. It drains seven states. And what we did, mostly after World War II, in the big build up of the Southwest, was to bring the entire river under management, to dam all of the major tributaries and the main stem itself. And what you do when you manage a river is that you store water during the big spring run-off and then distribute it for irrigation. Late in the summer you can distribute it to the cities, and importantly you can create a tremendous amount of hydroelectricity.
INSKEEP: I'm just trying to imagine that on a map here. You've got Lake Powell in kind of the center of the West. And from there the water zigzags down on the Colorado River through the Grand Canyon, gets to Lake Mead, is it? And then gets distributed all over the place.
Prof. WILKINSON: Yes. It goes to Lake Mead. And the two of them together hold four Colorado rivers behind them, if you can imagine that.
INSKEEP: And what are some major cities that depend on that water?
Prof. WILKINSON: Major cities are certainly Los Angeles. Los Angeles was the first. San Diego, Phoenix, Tucson to some extent, Las Vegas to some extent. And then upstream, you get water going out to the east of Denver and out to the west of Salt Lake City and to the southeast down to Albuquerque. It's the center of the West. And if there's a single place where all the visions and values and history and future of the West collide, it's at Glen Canyon Dam.
INSKEEP: Has there been more and more demand on that in recent years?
Prof. WILKINSON: Sure there has. And we're still wasting huge amounts of water, whether it's on the farms or in the cities. We've got to appreciate how much we can gain from conservation and perhaps address even the ultimate issue of growth and try to decide how far, how big of a build-out we want in our communities in terms of sustainability.
INSKEEP: But when you think about the fact the United States has 300 million people now and is forecast to have 400 million in a few decades, do community leaders in the Southwest want to make sure that their fair share of population growth ends up there?
Prof. WILKINSON: It's going to be interesting. And a person can wonder how we're going to bail ourselves out. We're going to bail ourselves out. We've got some civic leaders who really are starting to appreciate that we've got to set - build out limits.
INSKEEP: How do the different states and cities resolve their disputes over who gets how much of this water? That must be something that causes a city to rise or fall.
Prof. WILKINSON: The Colorado River is bound by an old and rigid and outmoded set of compacts and court decisions. It's called the Law of the River. And yet, because it is such a fundamental part of the law of the West, everybody's cautious about it. Everybody's scared. And particularly the lower basin states, who in fact - and that's California, Arizona and Nevada, particularly...
INSKEEP: Oh, they get the river last.
Prof. WILKINSON: They get the river last and the upper states are basically required to give them an amount that is unfair to the upper basin states. The upper basin states basically have to provide eight million acre-feet a year.
INSKEEP: Acre-feet. That's enough water to fill an entire acre for one foot?
Prof. WILKINSON: Yeah. An acre's about the size of a football field.
INSKEEP: Eight million a year? That's a lot of water.
Prof. WILKINSON: And they - that's right. But recently the seven western governors got together, and I think it's a transitional agreement. But I think it's an important one in which adjustments have been agreed to that will allow the upper basin states in times of drought to keep more water and create some flexibility down below so that the lower states can have banked water to be available in times of drought. And that's going to help. But the real deep changes that 50 years from now when people look back, we really haven't started to make them yet. And we're going to have to make them in the Law of the River, we're going to have to make them in our individual practices and the cities are going to have land use planning as well as water planning that's going to have to be done over that 50-year period.
INSKEEP: Mr. Wilkinson, thanks very much.
Prof. WILKINSON: Well, thank you.
INSKEEP: Charles Wilkinson teaches law at the University of Colorado at Boulder.