Is This Worth a Dam?

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And then there's the Glen Canyon Dam on the Colorado, which after its completion in 1963 not only robbed the Grand Canyon of sediment needed to rebuild sandbars and beaches but also drowned a spectacular landscape far bigger than the Hetch Hetchy Valley. Thanks to a multiyear drought that has only recently eased, the landscape has begun to re-emerge, energizing an effort by the Glen Canyon Institute to correct what conservationist David Brower called "America's most regretted environmental mistake." It's bound to be an uphill battle. The Glen Canyon Dam is part of the seven-state Colorado River water-storage and delivery system, with a large, powerful constituency that depends on it.

But what if the benefits provided by such dams could be replaced? Would that make their removal politically palatable? In a thick report on Hetch Hetchy released last fall, Environmental Defense argued that there are alternative ways to provide both the water and the power currently supplied by the O'Shaughnessy Dam. In one scenario, for example, the San Francisco Public Utilities Commission would shift its water storage over to the Don Pedro Reservoir, lower down on the Tuolumne River, which feeds the Hetch Hetchy System. But that could be tricky. Don Pedro belongs to the Turlock and Modesto Irrigation Districts, and those districts (whose rights to water from the Tuolumne River predate San Francisco's) are not eager to allow a large urban area to stick a big straw into the same precious pot.

The cost of retrofitting the Hetch Hetchy system, and who would pay for it, are other sticky issues. The total price tag for replacing the water and power that the O'Shaughnessy Dam provides, according to Environmental Defense, ranges from $500 million to $1.5 billion. The San Francisco Public Utilities Commission believes that the cost will be far higher, however--at least $8 billion if removal of the dam is included. Either way, it's a big chunk of change. By contrast, the cost of removing the Edwards Dam was just $3 million; it is estimated that taking out the Elwha dams will cost about $180 million, including a $30 million federal buyout of the dams' private owners.

As the debate over the O'Shaughnessy Dam continues, politicians and water managers throughout the Western states will be watching. This is a debate that has the potential to broaden into a long-overdue discussion of just how the rapidly growing population of this arid, drought-prone region plans to meet its water needs without sucking dry every river and aquifer. The future of development in the West may rest on what happens to this elegant dam and the valley it flooded so long ago.