Blocked by concrete or killed by climate?


In the context of climate change, our energy appetite has shoved us into a corner. We've gotten used to a diet of cheap, energy-packed fossil fuels, and it will probably be impossible to find an alternative that doesn't bring along its own set of environmental impacts: Solar arrays will damage deserts, wind farms decimate birds and bats, and where the heck will we site the transmission lines? 

And now the Idaho Statesman is describing another twist to the general dilemma: when it comes to killing salmon, hydro power dams and climate change are in fierce competition. Right now, dams may be decimating smolts by the millions, but wait a few decades and warmer water temperatures may stop southerly salmon populations -- and those that spawn in the summer -- dead in their tracks.

In light of those facts, the article poses the question: do we demolish dams or not? After all, argues the Statesman reporter, if we remove dams, fossil-fuel powerplants might replace them. Some salmon populations will benefit from unimpeded spawning runs, but will the added carbon emission result in a larger threat to the species as a whole? Which is more dangerous: millions of tons of greenhouse gases distributed in the atmosphere, or all those tons of concrete sitting in a river?

As the Statesman article puts it:

This means the hydroelectric dams that provide more than half of the electricity in (the Pacific Northwest) -- without emitting carbon dioxide -- are more valuable than ever.

That presents an ethical challenge to the environmentalists, Indian tribes and commercial and sport fishermen who have fought for years to reduce the impacts of dams on the fish. The dams are no longer just economic drivers in the region. They could be -- at least for the short term -- critical tools for reversing the most dramatic peril of our time.

It's a dilemma that hydropower interests have readily accepted:

"We are no longer in the time when these are economic versus environmental arguments," said Steve Wright, administrator of the Bonneville Power Administration, which markets the power from the dams and uses some of the proceeds to pay for fish recovery. "Increasingly these are environmental versus environmental arguments.

Though, if we're being asked to choose between big hydro dams or carbon emissions, we may be facing a false choice -- however much BPA might like to argue that dams actually protect salmon. As one voice in the Statesman article does point out, efficiency measures and other sources of renewable energy could mean that the hydroelectric turbines (in particular, four on the lower Snake River) won't necessarily be replaced with fossil fuels.