Hetch Hetchy Catch

There has been quite a bit of buzz lately about the possibility of tearing down the O'Shaughnessy Dam in Hetch Hetchy Valley in Yosemite, and progressives around the state are understandably enthusiastic. Perhaps even overly enthusiastic:

The lovely "liberals" in SF are all ape shit just because studies are showing that the restoration of Yosemite is not just feasible, but almost trivial. The reality that they can do something so good with only a minor changes to the water supply is a bit too real to handle.

I actually like the idea, in principle, and agree that it seems the water issues can be worked out, although I have not studied that side of the question too carefully.

What I have studied, however, and what most of the coverage of tearing down the dam ignores, is the power question. According to the Environmental Defense study that dam destruction advocates cite, somewhere between 20 and 40% of the yearly power output from Hetch Hetchy would be lost. Now, the California electricity issue is not without its complications (which we will go into this week, for sure), but the reality is that that power will have to be replaced. And, unfortunately, the reality in California today is that the power will be replaced largely by gas-fired power plants, and those plants will be located almost without exception in poor communities of color. The Environmental Defense study acknowledges that tearing down the dam will require new plants, but it handwaves the question of pollution by concentrating on CO2 emissions, rather than the more pernicious (and more localized) PM10s and PM25s.

If the California ISO is willing to sign off on tearing down the dam without replacement of its generating capacity, then I'm all for it, assuming the water and the money numbers work out. If not, though, we'll have to count the new asthma cases and the new stay-inside days that it'll cost.