347 



|503| 233-5823 

 Fax |S03| 233-3076 

 Northwest IrrigStiOn Utilities 825 NE Multnomah, suite tots • Portland Oregon 97232 



TECHNICAL MEMORANDUM 



DATE: July 26, 1993 



/ 

 TO: Dr. Dan Huppert, NMFS Coordinator, NMFS Economics Technical 



Committee (ETC) 

 NMFS Economics Technical Committee (ETC) 

 Dr. Don Bevan, Chairman, NMFS Salmon Recovery Team 

 Gary Smith, Deputy Director, NMFS Seattle 

 ESA Administrative Record ^^ 



FROM: Darryil Olsen, Ph.D. <V^ 



Regional Planner/Resource Economist 

 NMFS ETC Member 



SUBJECT: Review of Technical Evaluations Related to a Drawdown of the John 

 Day Pool from Minimum irrigation Pool (Elevation 262.5-263.5) to 

 Minimum Operating Pool (Elevation 257) 



The following material summarizes some of the recent biological and economic studies 

 evaluating a change in Columbia River system operations, to implement a John Day Pool 

 drawdown. It will be important for the NMFS Economics Technical Committee (ETC) to 

 be aware of several of the l<ey assumptions and findings contained within these studies, 

 as the ETC proceeds with its modelling and cost estimation wort< for recover measure 

 cost-effectiveness analyses. 



Ute-cycle model estimates of the biological effectiveness for a John Day Pool 

 drawdown indicate that very little, If any. benefit would be obtained for the Snaife 

 River salmon stocics. 



Biological benefit estimates developed by Anderson (1993a) for a drawdown of the John 

 Day Pool indicate that either: 1) no improvement to total smolt survival below Bonneville 

 Dam would exist; or 2) survival improvements would be very small and only exist under 

 optimal assumptions for both Snake River and John Day Pool drawdown conditions (see 

 Table 1). 



For example, with the existing smolt transportation program in place, less than 5% of the 

 spring Chinook, Snake-Columbia smolt migration actually passes through the John Day 



Icnganoo • /^qnailtl« • Enwgy 



