622 



search of existing experience, applicacion of theory and modeling, prococype 

 Cescing, and che applicacion of seasoned judgmenc is needed before che 

 feasibility can be confirmed. These key factors and suggested means to obtain 

 answers follow: 



Biological 



The smolts willingness to enter and stay in the transparent pipeline should be 

 greatly improved over opaque pipelines. Final proof of this would be with a 

 prococype test but preliminary work could be with a smaller test section. 

 Smolcs ready for downstream migration woul'd be needed for the final proof but 

 ocher species mlghc be suitable for earlier testing. 



The effects of che pressure change across a pump module can be reduced by 

 having a larger number of smaller pumps distributed down the pipeline. For 

 example, Che frlccion loss which muse be accounced for per 10 mile section of 

 24" plastic pipe, flowing ac 2.5 fc/sec or 1.7 mph would be abouc 42 feec of 

 head or 18 psl. If chls change is coo large for low smolc morcality, a closer 

 pump spacing could be provided. 



The possibilicy of abrasion or other contact damage to the smolcs is somewhac 

 offsec by che nacural veloclcy profile across a flowing pipe where the 

 velocity at the cencer Is che hlghesc and drops off sharply near che wall. 

 Tending Che oCher direccion would be the pressure change through the pump 

 module which may cause the smolts to rise in counceracclon Co che increase in 

 pressure. A concinuoua prototype test loop of near operational size and 

 pressure change may be needed to obtain facts on these questions. 



