This report responds to a request for assistance from the Northwest Power Planning Council (Council) dated January 7, 1998 on issues related to the planned capital construction projects of the U. S. Army Corps of Engineers (Corps or COE) (i.e., the Corps’ Columbia River Fisheries Mitigation Program, or CRFM Program).The U.S. Congress, in its appropriations bill for FY 98 directed the Council, with assistance from the Independent Scientific Advisory Board (ISAB), to review the mainstem Columbia River capital construction program of the Corps. The review is to evaluate the technical need for costly fish passage strategies at mainstem dams. The Northwest Power Planning Council document of January 7, 1998, identified sets of general and specific questions that Council staff initially felt would help focus the review by the ISAB (Appendix A). Subsequent discussions with the ISAB narrowed the focus at the outset to near-term and long-term assignments.
The three near-term assignments are:
- Role of mainstem fish bypass measures in an ecosystem approach for the Columbia/Snake rivers;
- Review of the scientific basis for future investment in extended-length bar screens at John Day Dam;
- Review of the scientific basis for juvenile fish passage improvements at Bonneville Dam.Long term assignments to be completed in December include reviews of the COE’s programs for surface bypass and dissolved gas abatement (tentatively scheduled for completion in September 1998) and a comparative evaluation of multiple technologies for aiding downstream passage of salmonids.
The Council established a policy context for the review of the CRFM Program concerning possible major alternatives for future configuration of mainstem hydroelectric dams presently under consideration in the region. The following four future alternative system configuration scenarios provided sideboards for the review:
- All existing mainstem dams, including dam modifications, remain in place and operational for the foreseeable future.
- All dams remain in place except that the four lower Snake River projects are breached to provide a natural river condition in the Snake River within the next 5-10 years.
- All dams remain in place except that a lower Columbia River project, such as John Day Dam, is breached or lowered within the next 10 years.
- Dams remain in place except that the four lower Snake River projects are breached to provide a natural river condition in the Snake River and John Day Dam is breached or lowered in the Columbia River within the next 5-10 years.
During 1999, the region will receive additional guidance on operational scenarios. The National Marine Fisheries Service is scheduled to issue a longer term Biological Opinion on the operation of the federal Columbia River hydroelectric system in 1999.