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Question S : Please provide the annual cost of foregone power sales due to water withdrawn 

 from the Columbia River and its tributaries for irrigation purposes, where such 

 irrigation is accomplished using power supplied by Bonneville. Also, please 

 estimate the cost of foregone power sales for water withdrawn outside BPA's 

 service area. What is the total volume of water withdrawn from the Columbia River 

 and its tributaries for irrigation purposes? If necessary, please consult with the 

 Army Corps of Engineers and Bureau of Reclamation in developing your response 

 to this question. 



Answer: In January 1993, the A. G. Crook Company published a draft report under contract 



with BPA entitled J 990 LEVEL MODIFIED STREAMFLOW. The report identified 

 a total of 7 million acres of irrigated lands in the Columbia River Basin upstream 

 from Bonneville Dam. This was broken down into: 2.2 million acres upstream of 

 the confluence of the Columbia and Snake Rivers; 4.1 million acres in the Snake 

 River Basin and 740 thousand acres downstream from the confluence of the 

 Columbia and Snake. The report stated that the irrigation use depletions ranged 

 from 1 to 3 feet of water annually for each acre depending on the type of crop, 

 method of irrigation used and the location. Assuming an average depletion from 

 irrigation of 2 feet per acre basin-wide that amounts to about 14 million acre-feet of 

 depletion from the entire Columbia River Basin which includes the Snake River 

 Basin A preliminary estimate of the depletion in the Snake River Basin has been set 

 at 7 million acre feet by A. G. Crook. A very rough number of the additional 

 generation that could be achieved if no depletion occurred is approximately 6-12 

 million MW-hrs. If the power was sold at $25/MW-hr, the annual depletion 

 translates into $150 - S300 million dollars. We have not spent a lot of time 

 developing these numbers but we believe this is a reasonable estimate. 



Several years ago BPA's Power System Branch conducted two power studies at 

 different levels of irrigation depletion—the depletion in 1980 compared to an 



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