Report of the Secretary of the Army
on Civil Works Activities for Fiscal Year 1994
Department of the Army Corps of Engineers
Extract Report of the Walla Walla District

Columbia River Fish Mitigation Program (Walla Walla Projects), Oregon, Washington, and Idaho

Existing project. The eight Corps hydroelectric projects on the Columbia and Snake Rivers have been identified as a major contributing factor in causing mortality to downstream migrating juvenile salmon and steelhead. Without adequate bypass facilities to guide these juvenile fish away from the power turbines at the dams, mortalities incurred through project passage severely impact the commercial, recreational, and Indian fisheries. The Corps has recognized the need to reduce juvenile mortality and has undertaken bypass measures that include mechanized fish bypass systems with barge and truck transportation. Spill, as an additional bypass route over the spillways, has been used to divert fish from entering turbine units; but it is a significant adverse economic factor due to lost power revenues. Congress passed and the President signed the Fiscal Year 1989 Energy and Water Development Appropriation Act (PL 100-371), which mandated the expenditure of funds for the design, testing, and construction of new or improved fish bypass facilities for the Columbia River Fish Mitigation projects. Completion of bypass and transportation facilities will significantly increase the survival of migrating downstream juvenile fish. The mitigation study will determine the overall scope of the fish mitigation facilities for these Columbia and Snake River dams.

The plan of improvement includes the following facilities: 1) Ice Harbor: screens, new gantry crane, collection bypass facility, intake gate raise, spillway deflectors, surface bypass, fish ladder temperature control; 2) Little Goose: screens, gantry crane modification, collection bypass facility, outfall pipe, remaining double-length submerged traveling screen/submerged bar screen, prototype vertical barrier screens, remaining vertical barrier screens, fish ladder temperature control, fallout fences, gate raise, deck screen modifications, and surface bypass; 3) Lower Granite: juvenile fish facility, gantry crane, gate raise, outfall pipe, fish barges, screens, remaining double-length submerged traveling screens/submerged bar screens, additional moorage facility, fish slot closures, juvenile facility improvements, barge exit modifications, deck screen modifications, fish ladder temperature control, surface bypass, fallout fences; 4) Lower Monumental: hold/load and collection bypass facility, screens, pit-tag facility, barge load facility modifications, barges, gate-raise modifications, gantry crane, screen repair pit, fish ladder temperature control, surface bypass; 5) McNary: gantry crane, screens, hold/load facility, gate-raise modifications, submerged vertical barrier screens remaining, submerged double-length screens remaining, debris/screens, tilted weirs fish ladder, maintenance facility, fish ladder exits, hold/load facility, gantry crane modifications; and 6) a mitigation study that analyzes long-term alternatives to mitigation for fish losses at Corps dams on the Columbia and Snake Rivers.

The current total estimated fully-funded Federal project cost is $281,300,000 for the Walla Walla projects.

Ice Harbor bypass facilities were not initially authorized for construction under the Columbia River Juvenile Fish Mitigation Program. However, in Fiscal Year 1989, Congress authorized expenditures to proceed with design of a bypass system. The mitigation study project was added to the President's Fiscal Year 1991 budget.

Local cooperation. None required.

Operations during fiscal year. Fabrication was completed on the new gantry crane at Ice Harbor. Design was completed for double-length submerged traveling screens at Little Goose, Lower Granite, and McNary Dams. Construction was completed on the contract for the collection/bypass and holding/loading facility at McNary Dam. Mitigation study Phase I draft report was completed in April 1994, and the final report is scheduled for completion in Fiscal Year 1995. Final scoping of Phase II is dependent on the outcome of Northwest Power Planning Council's "rule making report" scheduled to be completed in December 1994, and the National Marine Fisheries Service recovery plan scheduled for release in January 1995.

Fiscal Year 1994 costs were $27,347,817. Total project costs through Fiscal Year 1994 are $130,970,413.