Dam Trade-Offs:

The Reason Foundation's Shikha Dalmia challenges environmentalist calls to remove dams from western rivers. Hydroelectric dams may have been wasteful and environmentally destructive boondoggles when they were built, but now that they are in place they provide relatively cheap electricity without emitting carbon dioxide.

Once regarded as the symbol of national greatness, hydroelectric dams have now fallen into disrepute for many legitimate reasons. They are enormously expensive undertakings that would never have taken off but for hefty government subsidies. Worse, they typically involve changing the natural course of rivers, causing painful disruptions for towns and tribes.

But tearing down the Klamath dams, the last of which was completed in 1962, will do more harm than good at this stage. These dams provide cheap, renewable energy to 70,000 homes in Oregon and California. Replacing this energy with natural gas--the cleanest fossil-fuel source--would still pump 473,000 tons of additional carbon dioxide into the atmosphere every year. This is roughly equal to the annual emissions of 102,000 cars.

Given this alternative, one would think that environmentalists would form a human shield around the dams to protect them. Instead, they have been fighting tooth-and-nail to tear them down because the dams stand in the way of migrating salmon. Environmentalists don't even let many states, including California, count hydro as renewable.

Yet hydro is not the only power that some environmentalists oppose. Nearly every viable alternative energy source has provoked some amount of environmentalist opposition.

Their opposition to nuclear energy is well known. Wind power? Two years ago the Center for Biological Diversity sued California's Altamont Pass Wind Farm for obstructing and shredding migrating birds. ("Cuisinarts of the sky" is what many greens call wind farms.) Solar? Worldwatch Institute's Christopher Flavin has been decidedly lukewarm about solar farms because they involve placing acres of mirrors in pristine desert habitat. The Sierra Club and Wilderness Society once testified before Congress to keep California's Mojave Desert--one of the prime solar sites in the country--off limits to all development. Geothermal energy? They are unlikely to get enviro blessings, because some of the best sites are located on protected federal lands.

What to do? No source of energy is perfect; all involve trade-offs. Some like to think conservation is the cure, but marginal reductions in energy use will only do so much. If global warming is the greatest environmental threat, then it may be worth enduring other environmental impacts to reduce carbon dioxide emissions. In a world of infinite trade-offs, we can only do so much.

UPDATE: American Rivers responds here. Their bottom line: "To say that all dams are beneficial and should be protected, . . . is as absurd as saying all dams are bad and should be removed." The issue is which dams should (or should not) be removed and why.