Ill 



to get in-river smolt migrants past the dams, and (2) it is the best wav to provide 

 an equitable balance between smolts transported in barges and tiiose allowea to mi- 

 grate in-river. 



A key component of improving in-river migration is getting the smolts past each 

 dam. Tnere are currently three possible ways for in-river iuvenile migrants to pass 

 the dams: through the turbines, through the mechanical Dvpass and transport col- 

 lection system, or through the spillway. IDFG, and all other fisherj; management 

 agencies and tribes in the Northwest, believe that managed spill provides the safest 

 route for in-river migrants to get past the dams. The turbine route (8-19 percent 

 mortality) results in approximately five times more mortality than spill (0-3 per- 

 cent) or mechanical bypass (1-3 percent) routes (NMFS 1995). 



The best way to mimmize turbine passage for in-river migrants is via a controlled 

 spill program. Without spUl, all fish that are not mechamcally bypassed must go 

 through the turbines. The efficiency of the bypass system at Lower Granite Dam 

 is typically less than 60 percent. Thus, without spill, over 40 percent of the smolts 

 will be forced to pass through the turbines. 



SpUl can be managed in concert with the bypass system at most dams to achieve 

 an 80 percent fish peissage efficiency (FPE). This means that 80 percent of the fish 

 will be provided a non-turbine route past the dam (either spiU or mechanical by- 



fass), and only 20 percent of the in-nver migrants will pass through the turbines. 

 DFG beUeves adopting an 80 percent FPE standard at all dams on the lower Snake 

 and Columbia rivers is one of the most important interim steps we can take toward 

 recovery. Managing spill to achieve an 80 percent FPE requires no flow augmenta- 

 tion fi^m upstream storage reservoirs, but simply reapportions existing water flow- 

 ing past the dam. 



The National Marine Fisheries Service's spill policv includes an 80 percent FPE 

 standard, but does not implement that standard xinless flow targets (e.g., 85 kefs 

 or 100 kefs) are met at the lower Snake River dams (NMFS 1995). These flow tar- 

 gets may not be met during much, or any, of the smolt migration season, resulting 

 in over 40 percent of the smolts passing through the turbines at the first dam they 

 encounter. iDFG believes spill should be decoupled from these flow targets, and that 

 the 80 percent FPE standard should be implemented regardless of flows, except per- 

 haps during extreme drought conditions. 



IDFG also believes that spill should be provided at transportation collector dams 

 as a means to achieve a more equiteble balance between smolt transportation and 

 in-river migration. This important interim strategy is necessary until long-term so- 

 lutions can be implemented (e.g., dam modifications, surface collectors, ete.). The 

 smolt transportetion program — which often transports over 85 percent of the total 

 number of migrating spnng/summer chinook — ^has failed to reverse the downward 

 trend in returning adult smmon (Olney et al. 1992; Mundy et al. 1994). Given the 

 uncertainties regarding salmon biology, common sense dictates that we should not 

 "put all our eggs" in uie transportation basket. Providing spill at mainstem dams 

 allows a portion of the downstream run to continue their in-river migration under 

 the best oam passage conditions we can create. 



Scientific information supports a more even balance between the number of fish 

 transported and the number of fish allowed to migrate in the river. Higher adult 

 returns are tvpically associated with smolt outmigration conditions that have higher 

 flow and spill, with more smolts migrating in-nver and fewer smolts transported 

 (Figures 1 and 2). Preliminary adult return information fii^m PIT togged juveniles 

 indicates that in-river migrating smolts returned at least as well as transported 

 smolts, even though in-river conditions were far fix)m optimal (Harza Northwest 

 1994). Independent scientific review also failed to support continued emphasis on 

 transportation (Mundy et al. 1994). 



Improving in-river smolt migration conditions will always be important because, 

 even if full transportation is continued, it is impossible to transport all juvenile mi- 

 grants. At maximum transport 40-50 percent of smolts leaving Idaho will go 

 through the turbines at the first dam they encounter (Lower Granite Dam) and not 

 be transported. This is because of the inefficiency of the smolt bypass system. Many 

 of Uiese fish will be picked up at downriver dams but at least 10-15 percent of the 

 smolts will remain in the river. Improving in-river migration conditions is also im- 

 portont for getting smolts to the transportation collection facilities. 



2. What independent scientific research is being conducted to monitor the effects 

 of spill and its alternatives in the Columbia River system? 



Spill is a management tool with known benefits, risks and applications. There are 

 no critical uncertainties that preclude immediate implementation of spill as an 

 adaptively managed recovery tool. As discussed above, there is firm scientific sup- 

 port of usingmanaged spiU to aid recovery now, not just implement as a limited 

 experiment. This scientific basis for spill was recognized recentiy by a Federal En- 



