Dams for Patagonia

In rolling hills at the foot of a basalt massif, the people of this compact, ordered town live mainly by fishing and cattle ranching. For many, life is not dramatically different from that experienced by the pioneers who first cleared the valley nearly a century ago and built timber homes. But graffiti around town reveal a new disquiet. "Patagonia Sin Represas!" ("Patagonia Without Dams!") is perhaps the politest of the slogans sprayed across the walls and buildings of this place, the capital of the Aysén region in Patagonia. They reflect anger over plans to build at least seven major hydropower dams in the area.

Home to condors and alpaca-like guanacos, puma, and blue whales, Patagonia is the tail end of the Americas, one of the last accessible nowhere lands on the planet. It contains the Southern Ice Field, the world's third most important reserve of freshwater after Antarctica and Greenland. And in its untamed wilderness of glaciers and mountain peaks, companies are preparing to raise not just hydrodams but also a 70-meter-high transmission line to transport power more than 2400 kilometers north to Santiago, Chile's capital, and the energy-hungry mines beyond. The line would require one of the world's biggest clearcuts, a 120-meter-wide corridor through ancient forests—fragmenting ecosystems—and the installation of more than 5000 transmission towers.

Proponents of the dams argue that hydroelectricity is a clean source of energy, that Chile needs the 3500 MW/yr of power to meet its development goals and, lacking oil or coal reserves, has no viable alternative (see sidebar, p. 384). But more than 50 international environmental groups have come together to try to block dam construction under the umbrella organization that uses the slogan "Patagonia Sin Represas" as its name.

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