An Independent Peer Review of Two Models Estimating Potential Chinook Salmon Production After Dam Removal and Habitat Restoration on the Klamath River

This is an independent expert review of two separate and different approaches for estimating the Chinook salmon production potential of the Klamath River Basin before and after proposed removal of four mainstem dams and implementation of the Klamath Basin Restoration Agreement (KRBA). The information provided in the two modeling endeavors, as well as this and other peer reviews, will be used in a determination to be made by the Secretary of the Interior, in consultation with the Secretary of Commerce,
regarding removal of four hydroelectric dams on the Klamath.

The two reports were reviewed with respect to the stated Terms of Reference. Comments were made on both specific detailed concerns, as well as broader, overarching issues that might influence the appropriateness of respective approaches. Taken together, the reports by Hendrix (2011) and Lindley and Davis (2011) represent significant work contributing to the estimation of the numbers of fish that could
potentially be produced after Klamath River dam removal and implementation of the KRBA. Both approaches described used a variety of innovative and state-of-the-art modeling techniques for their estimates. However, as noted in the detailed review below, there are several major concerns that have the potential to bias the results of both approaches, most likely in a downward direction. The reliance on existing and recent production data per habitat in other watersheds (both Hendrix, and Lindley and Davis)
and within the Klamath (Hendrix) has the potential of underestimating the actual habitat capacity. Prior to further investigations on these issues, however, and assuming other review comments are addressed, I believe the methods presented in the two reports provide sufficiently robust results to serve as preliminary, albeit likely conservative, estimates of the Chinook production benefits to be gained by dam removal and the KRBA program.