Shoshone-Bannock Tribes - Idaho Power

Idaho Power CompanyResponses to CommentsRESPONSE TO COMMENT SBT1-71IPC believes that several factors preclude reestablishing fall chinook to the Snake River abovethe HCC. Much of the habitat will remain inundated by the reservoirs and is therefore no longersuitable for spawning, and the balance of the remaining habitat is highly degraded and, underpresent conditions, would not support high enough survival to sustain natural runs. In light of thepresent condition of upstream habitat and water quality, IPC contends that any efforts toreestablish anadromous fish above the HCC are premature. These habitat and water qualityconditions are the result of natural and anthropogenic influences. Efforts are underway toimprove water quality and IPC, through the draft Snake River–Hells Canyon TMDL and otherwater quality projects, is a participant in such efforts. While water quality and habitat above theHCC must improve before reintroduction of anadromous fish should be considered, it is not theonly variable that must improve before reintroduction makes sense. The populations ofanadromous fish that currently must negotiate eight downstream hydroelectric projects (ownedand operated by the federal government) and that use habitat below the HCC of good to excellentquality are exceedingly depressed and are not self-sustaining. Passing those same fish upstreamof three additional hydroelectric projects, into habitat of questionable quality, would not increasetheir abundance or sustainability or lead to recovery of the ESA-listed species; it would likelyonly complicate it. Moreover, available habitat downstream of the HCC is currently significantlyunderseeded.RESPONSE TO COMMENT SBT1-72This section is talking about historical abundance only. There is not enough information to havehigh confidence in an estimate of what historical abundance of steelhead was in the Snake River.IPC did provide an estimate based on some crude assumptions regarding steelhead.RESPONSE TO COMMENT SBT1-73This section is saying that part of the estimate for steelhead adult abundance before the HCCrelied on the return of adults to traps from juvenile outmigrants that migrated to the ocean priorto completion of the dam. It is not saying that the HCC did not impair the movements ofanadromous fish.RESPONSE TO COMMENT SBT1-74IPC has fully considered HCC impacts on anadromous fish. For a complete discussion ondevelopmental impacts of anadromous fish, see Technical Report E.3.1-2.RESPONSE TO COMMENT SBT1-75IPC relied on trapping data during the construction period of the dams to make estimates of whatthe abundance of anadromous fish was just prior to the construction of the HCC. Very littlerecords were kept on the abundance of anadromous fish in this area to make any other estimates.Hells Canyon Complex Page 59