This is a generally well-prepared proposal for an ongoing project that has produced useful results. The additional work coupled with the hydrodynamic modeling should be very helpful to hydrosystem operators.

The proposal clearly explains the technical background of the project and identifies a need for the research. It mentions that the highest potential spawning areas for fall Chinook in the mainstem Columbia and Snake Rivers have been reduced to 6% of historical areas, but it was not clear whether this figure included the preferred spawning areas in the lower reaches of major tributaries. The proposal does a good job of identifying the potential to adjust operations of the lower Snake River dams in order to improve tailrace spawning potential. The background also identifies that microhabitat analysis has provided limited insight into predicting what characteristics salmon require when they decide where to spawn. The weakness of the background is that it has does not provide compelling evidence that they have overcome this limitation, and that they are, in fact, capable of making measurements on habitat, modeling flow, and then determining what the quantity and quality of the habitat might be. The predictions need to be tested empirically, if possible.

The proposal places the research in the context of the 2000 BiOp, and relates the study to knowledge gaps identified in Independent Scientific Group and ISRP reports. While it does link the study to the Council's Fish and Wildlife Program, it does not specifically mention subbasin plans. The proposal describes the partnership with the USACE and the history of hydrodynamic modeling, and it mentions some of the other Snake River Chinook projects. However, it does not mention the ongoing life history projects or discuss how hydrosystem operations to improve spawning habitat could affect other segments of the life cycle (e.g., outmigration timing). The project history is informative about what the project did, but not what they have found so far. More details on results would have been helpful.

There is a very clear set of objectives, hypotheses, and timelines. The introductory material provides a good overview of the study, although there are few explicit references to how the study addresses planning objectives (other than the overall objective of increasing natural fall Chinook spawning). As the work progresses, numerical objectives may be needed to justify the costs to the hydrosystem of operational changes.

The methods build on the results of previous research in this project. For the most part, they use the latest technology and address the various controlling factors on substrate morphology. The hydrodynamic modeling work could be very helpful in guiding hydrosystem operations. There is some weakness among the goals, the data they are going to collect, and the inferences they hope to make, which provoke a sense of caution. The assertion that the product of the proposal provides a means for linking effects of physical habitat variables to measurable biotic parameters and ecosystem processes is limited to a post-hoc description of what they observed, not a prediction of what would happen at other sites. The determination of quantity and quality of habitat suffers from lack of precise definition of each and how they are measured in the field and analyzed. It seems likely that these measures will not provide self-evident conclusions. Rather they will be inferences open to debate about their veracity, with a need to be established by empirical testing.

The monitoring and evaluation methods are clearly identified. To some extent, the investigators are at the mercy of the weather and Snake River discharge, but they should have at least some real-world conditions with which to compare model outputs. It wasn't clear how the fluctuating flows under load following would be factored into their model.

The personnel are highly qualified for this project. Similar work is being done in tailwaters elsewhere. The proposal mentions peer-reviewed publications and progress reports, but does not specify if or how data and meta-data will be archived and made available to the public. However, the Pacific Northwest National Laboratory has a good track record in this regard.

This project will clearly benefit naturally spawning fall Chinook salmon and could be very helpful if the US Army Corps of Engineers is willing to modify dam operations to create and maintain longitudinal bars in the tailraces that the salmon seem to prefer for spawning.