Earth be dammed

I noticed a pattern in each of the three sections of your book where first we see the unimaginably slow and powerful course of natural history, then there is a period of pre-modern use that tends to be highly adaptive and have a fairly low impact, and finally modernity comes with large-scale interventions that very quickly wipes out a lot of what came before.

Right.

So what's next?

Well, it depends what we do from here on out. The change that occurred on the River Murray as a result of the dams and weirs made happen in 150 years what would have occurred in a natural state over roughly 100,000 years. Obviously that sort of change can't continue very long before it takes humans with it. We're headed on a path toward disaster. That's not to say that all humans will be wiped out, but unless we change, there will be far, far fewer of us. The alternative to that is to start taking natural processes seriously and to work with them rather than to pretend that they don't exist, or stand in the way of them. In the end, they'll outlast us. There's no question about that.

This seems to get at a fundamental shift away from the view of nature as ours to master and toward a more urgent sense of our dependency on the natural world. Do you see this change happening?

I'd say that awareness is starting to spread, but it's only beginning. If you grow up with the sort of modern conveniences that most people in this country take for granted, you really don't have an opportunity to think about that, or at least there's no reason particularly why you would. It's not until these things start to break down that you might begin to pay attention and to ask why. I think among scientists in particular there's an awareness of the fragility of these systems and of the ways in which they're being overwhelmed. But while that awareness is spreading, it's yet to change policies sufficiently.

You write that large dams will someday be relics, as will gas-powered cars. How soon do you think that will be upon us?

Well, the timing is the hardest thing to predict. In the book, I put it safely into the future, in 500 or 1,000 years. Whether they'll become relics more quickly depends on each dam. There's a dam in China that by the time it was commissioned and began operation, a third of its reservoir was already filled with sediment. That's perhaps the most dramatic case. But there are plenty of dams that will age and outlive their usefulness over 50 or 100 years. In fact there are quite a few small dams in the United States that simply get abandoned when they no longer serve their purpose. Many were built in the 19th century and now they're just obstacles to fish. In many cases, the owners aren't even known, so it falls to the government to dismantle them. This is one of the ways that we fail to assess the true costs of dams.

I noticed that in the book you mention seeing a Domino's Pizza while you were in India. A similar occurrence famously sent Thomas Friedman into reveries about the coming of the "flat world." You seem to have a very different response to the trappings of globalization. Why do you think that is?

I think, in part, it's a lack of environmental awareness that makes people so enthusiastic about globalization. One of the things missing from Friedman's work is any examination of the environmental consequences. China's economy, for instance, is growing at a rate of 9 or 10 percent a year. There's no way it can continue to do that without sending itself over the precipice. Just in water terms, China is in huge, huge trouble and knows it. The Yellow River no longer flows to the sea for part of the year because so many dams have been built along it. There's so much groundwater being pumped in China that the land subsidence has become a problem all over the place. The groundwater is being depleted and once it gets to a point where it's so low that it's too expensive to pump it -- or there just isn't any more water to pump -- China's agricultural successes will come to a grinding halt. The same is true in India where groundwater depletion is a huge problem. And yet again and again we don't seem to take into account the environmental impacts of what we're doing. We think that the resources we are depleting will be there in perpetuity. There's a constant supply of fresh water. It doesn't get any bigger. There's no substitute for it. Yet we don't take that into account.

Do you think that the markets can be made sophisticated enough to account for what is really at stake with dams and similar projects?

I'm certainly no economist, but there's no question that a pricing system that took into account the true cost of constructing a dam and of having to dismantle it years later, as well as the many environmental impacts, would have a good effect. There's a big battle going over water privatization between multinationals and people who say that water is such a vital aspect of our being that it should never be privatized. The same people often say that therefore it shouldn't be priced. That creates a quandary because I think the only way people are going to value water the way they should is to have to pay a substantial amount for it. We would need to subsidize the poor so that they're not paying the full price for water, but there's no question in my mind that farmers have got to start paying fairly for irrigation. These suitable pricing systems could be introduced gradually, but we've got to start charging what things cost.

This issue of charging what things cost comes up often in the context of displaced people. There seems to be this idea that where there's no cash economy, there's no value, so displaced people from subsistence economies wind up getting nothing because, in the eyes of the World Bank, they had nothing.

Yeah, that came up in Lesotho, where there was an attempt to price out the loss of things like herbs that the downstream people used and would no longer have access to once the dams cut off the flow of the river. The market cost of these herbs would be almost nothing and yet they were very important to these people's livelihood. Somehow you have to have a way of taking these things into account. You also need to take into account the aesthetic value of a flowing river. I don't know of any pricing mechanism that does that. That comes into play in the current movement to take down the O'Shaughnessy Dam in Hetch Hetchy Valley, which supplies San Francisco with water.

I meant to ask you about that. I remember on visits to the Hoover Dam and the Glen Canyon Dam along the Colorado feeling seduced by their majesty and ingenuity, no matter what I happened to know about their destructiveness. Is there any pleasure for you in the sight of a large dam?

[Laughs] Well, there is a kind of awe that I feel when I see them. They're amazing structures and they're magnificent ones. Certainly the Hoover Dam was built with some aesthetic values in play -- polished terrazzo granite floors and art deco fittings. It's quite beautiful to go through, but the same is not true for the more utilitarian dams that have typically been built since then.

So is there any such thing as a good dam?

In rare instances there may be. The needs that call a dam into being may be so big as to be hard to ignore. It's hard to say that people of developing nations should be deprived of water, particularly when one in five people on the planet lack enough for their basic needs. But I think if we applied the standards of the World Commission on Dams -- if we examined every cheaper alternative and priced dams according to their true value -- we would build far fewer of them. And I'm willing to live with that standard. Building dams willy-nilly on every river is insanity.

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