The Hetch Hetchy Valley in California's Sierra Nevada mountains is the Lower 48's second most spectacular glacier sculpted valley of sheer granite cliffs. The most spectacular is of course Yosemite Valley, 17 miles to the south. In 1913, Congress handed the city of San Francisco the right to turn Hetch Hetchy into a reservoir and profit off the water and electricity. The battle against submerging this valley was one of the roots of activist environmentalism.
In the late 1980s, Reagan's Interior Secretary Don Hodel came up with a great divisive environmental issue: San Francisco, tear down this dam!
The citizens of San Francisco are finally going to vote on whether to even consider giving up this reservoir. Local Democratic politicians like Nancy Pelosi, Dianne Feinstein, and mayor Ed Lee are utterly opposed to restoring Hetch Hetchy to its natural state.
In general, I think that people on the right are way too concerned about trying to figure out correct universal principles when it comes to environmental issues. Instead, think of environmental regulations as tools. San Francisco Bay Area liberal politicians are smarter: they are adamant environmentalists when it is in their constituents' interests and adamant anti-environmentalists when it's not.