435 



Biological Benefits. Modifying Lower Granite Dam will provide further evidence on the correlation between water 

 velocity and salmon survival And it will help answer other key biological questions. How can juvenile and adult salmon 

 be safely passed through dams during drawdown? How well can fish be guided to the spillway, and how many are spilled 

 at various levels of spill? In drawdown, how will collection and bypass facilities operate, and what adult ladder attraction 

 flows are necessary? 



But a decision to modify Lower Granite now must also be based upon a commonsense deference to the already- 

 settled conclusion of Northwest federal, state, and tribal salmon experts. Based on substantial evidence from pre-dam and 

 post-dam high flow years, ttxey have concluded that stirvival increases as hydrosystem velocities increase. 



Sufficient evidence and expen consensus exists now to take this first step. Tliat step in turn will provide further 

 evidence for deciding what the next steps are and whether to take them. 



Economics. The best present cost estimates of this proposal are atQched in tabular form. Capital cost estimates are the 

 Army Corps'; impact estimates are the National Marine Fisheries Service's Economics Technical Committee's. 



Capital Investments. The Corps estimates capital cost at $70-90 million, including dam modifications themselves 

 plus pump modification for irrigaton and industries. This is far less than one year's cost of purchasing water to achieve 

 the same velocity. And it is a capital investment-once spent, it pays continuous dividends. By contrast, fish barging and 

 water purchases require perpetual annual expenditures. 



Power Impacts. NMFS estimated the firm energy impact of a 2-month Lower Granite drawdown to be between a 

 40 megawan (MW) gain and a 40 MW loss. The midpoint is no impact. Midpoint impact estimates to non-firm energy 

 and capacity total S8.7 million annually. Actual impacts would lessen widi time, as the regional energy system adjusts to 

 these predictable slight losses. 



Navigation Impacts. NMFS estimated a 2-month Lower Granite drawdown would cause annual losses to ports 

 and port users of $2.45~$3.25 millioiL Mitigation likely requires a combination of capital expenditures and annual 

 payments, again declining over time as market adjustments occur. These losses are well below the aimual public subsi- 

 dies that ports and users now receive-lock operation and maintenance, navigation channel dredging, etc. 



Irrigation Impacts. Once irrigation, industrial, and municipal water pumps are extended, for about $6 million, the 

 only impact would be a slight increase in pumping costs. The region could mitigate that increase for a negligible annual 

 cost. 



Fisherv Impacts. A Pacific Rivers Council study estimates that, even in its currently depressed state, salmon 

 fishing pumps $1 billion yearly into the Northwest economy, and maintains 60,000 jobs. Restoring Snake River salmon 

 will increase that economic benefit by restoring Idaho's salmon fishery. And it will maintain or increase downstream 

 benefits by easing current constraints on harvest of other salmon stocks to protect the weak Snake stocks. 



Law. The Northwest Power Act requires "flows of sufficient quality and quantity" for salmon migrating through the 

 federal hydrosystem. In the lower Snake, drawdowns are the only way to provide those flows. The E ndangered Species 

 Act requires recovery of listed salmon in tasii natural habitat. For dieir lower Siuke habitat, drawdowns are the only way 

 (aside from dam removal) to restore its usability. Finally, drawdowns will also help the United States meet its treaty 

 obligations to Northwest tribes. 



