Arrowrock Dam Outlet Works Rehabilitation

AGENCY:

Bureau of Reclamation, Interior.

ACTION:

Notice of Availability of Record of Decision.

SUMMARY:

This notice is issued under authority of the National Environmental Policy Act of 1969. The Record of Decision (ROD) signed on April 30, 2001 contains the decision of the Department of the Interior, Bureau of Reclamation (Reclamation) Pacific Northwest Region, to select and implement the Preferred Alternative (Alternative A), as described in the Final Environmental Impact Statement (FEIS). Alternative A was identified as the environmentally preferred alternative in the FEIS. This alternative best achieves the project objectives and meets the purpose and need of the project in an environmentally sensitive manner.

ADDRESSES:

Copies of the ROD may be requested from the following locations:

• Bureau of Reclamation, Pacific Northwest Region, 1150 North Curtis Road, Suite 100, Boise, ID 83706-1234.
• Bureau of Reclamation, Snake River Area Office, 214 Broadway Ave, Boise, ID 83702-7298.
• The ROD is also available for viewing or downloading on the internet at http://www.pn.usbr.gov/project/arrowrock/arrowrock.shtml .

FOR FURTHER INFORMATION CONTACT:

Steve Dunn, Environmental Specialist, (208) 334-9844.

SUPPLEMENTARY INFORMATION:

Pursuant to section 102(2)(C) of the National Environmental Policy Act of 1969, as amended, Reclamation prepared a FEIS to examine the impacts of alternative methods to rehabilitate the outlet works at Arrowrock Dam by removing the 10 lower level Ensign valves and replacing them with clamshell gates. Two action alternatives were identified that differed only in the timing of reservoir drawdown and the elevation of Arrowrock Reservoir and Lucky Peak Lake in the third construction season. The preferred alternative (alternative A) requires a longer period of drawdown of Arrowrock Reservoir, but both Arrowrock Reservoir and Lucky Peak Lake would remain at a higher elevation than with the other action alternative. Based on comments received on the Draft EIS concerning impacts to water quality and bull trout, the preferred alternative was modified so that the probability of sluice gate use, which could release large amounts of sediment form Arrowrock Reservoir, was reduced from 42% to 15%. The No Action Alternative, which included actions that would be required for an intensive maintenance program if the Ensign valves were not replaced, was also evaluated.