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200727300 - Evaluate the effects of hyporheic exchange on egg pocket water temperature in Snake River fall Chinook salmon spawning areas

Sponsor: Pacific Northwest National Laboratory

Budgets: FY07: $163,547 | FY08: $210,086 | FY09: $193,557

Short description: The research to be conducted under this proposal will evaluate relationships among river discharge, hyporheic zone characteristics, egg pocket water temperature, and emergence timing of Snake River fall chinook salmon.

view full proposal

Final Council recommendation (Nov 2006)

Funding category: Expense

Recommended budgets: FY07: $0 | FY08: $0 | FY09: $0


ISRP final recommendation: Fundable (Qualified)


The proposal lays out a case for developing a better understanding of the effects of surface-hyporheic water exchange on the developmental rate and survival of fall Chinook eggs and alevins below the Hells Canyon dam complex, and whether operation of the dams can generate flow conditions that improve survival and accelerate embryonic development. The working hypothesis is that water releases from upstream storage reservoirs and the timing of spill can be adjusted to increase egg survival and cause fry to emerge earlier. In general, the objectives are clearly stated and specific timelines are given. Our main concern had to do with sample size. Fourteen sites, 25% of the total number of "most used" spawning areas, have been selected (a map would have been helpful). While this seems like a plausible number of sites for a general survey of Chinook reproductive success, the proposal did not really address the question of how many sites would be needed to achieve the overall objective of developing a better understanding between egg survival, hyporheic flow dynamics, and modified reservoir operations. At $10-15K per sample site per year, it is important to sample enough sites to answer the central questions, but at some point adding sites may not yield much additional information. Nevertheless, as long as sample size is reasonably justified, this should be a worthwhile effort.

State/province recommendation: Not fundable

Review group: OSPIT - Blue Mountain

Recommended budgets: FY07: (n/a) | FY08: (n/a) | FY09: (n/a)


State/province recommendation: MS: Recommended Action

Review group: MSRT

Recommended budgets: FY07: (n/a) | FY08: (n/a) | FY09: (n/a)

Comment: This project should probably be funded by Idaho Power Company and considered in the FERC relicensing process. Any recommendations as a result of this project would have to be implemented by IPC.