Phone: 801-524-3684
Fax: 801-524-5499
Email: ea_comments@uc.usbr.gov

Dear Ms. Coulam,

I submit the following scoping comments for the draft Environmental Assessment (EA) that the Bureau of Reclamation (BOR) is presently preparing for the proposed temperature control device (TCD) at Glen Canyon Dam, Arizona.

While it is critical that urgent action be taken to address the decline of endangered species in Grand Canyon National Park caused by Glen Canyon Dam's operations, the TCD initiative now underway may only further the native ecosystem's collapse. Its operation could actually bring the few remaining native fish closer to extinction, constituting an incidental take of endangered species.

The situation is particularly critical for the humpback chub, whose numbers have declined 85 percent since 1982. This decline, combined with abundant new information about the condition of the ecosystem in Grand Canyon since the TCD was recommended in 1995, compelled the BOR to halt the fast-tracking of the TCD proposal and undertake a more thorough review of the situation in Grand Canyon, including the full range of alternatives available to address them. Specifically, I request the BOR address the following:

1) The present environmental review process be expanded to a full Environmental Impact Study to address the TCD and all new information that has come forward since the first Glen Canyon Dam EIS was completed in 1995.

2) Other alternatives to warming the water, including permanently lowering the reservoir and decommissioning the dam.

3) The potential for the TCD's operation to increase the population of non-native fish such as catfish, carp and brown trout, which are known to prey on the young of endangered fish species.

4) The effect the TCD will have on water quality, including new and increased levels of exotic animals and parasites. Specifically, it should address impacts to the New Zealand mud snail and the Asian tapeworm, which are not native to Grand Canyon ecosystem; and how will these impacts affect the recovery of the native fish, which were not addressed in the original EIS.

5) The TCD's potential impacts on the aquatic food web for Grand Canyon's native fish. This includes the impacts associated with the worsening drought situation and the quality and quantity of nutrients to provide carbon for the river's food chain.

6) The complimentary role other mitigation measures must play, especially sediment augmentation to replace the loss of 95 percent of Grand Canyon's sediment and nutrients trapped behind the dam, and the restoration of flow regimes that mimic the rivers annual, natural hydrograph.

7) The safety risks that these modifications to the penstocks my pose to Glen Canyon Dam, especially at low water levels.

Thank you for the opportunity to submit these comments.

Sincerely,

Your name or organization

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Last Update: October 30, 2007