The Hells Canyon Case 137 



possibilities under which this economic gain could be used to 



induce a private firm to undertake the socially more economic 

 scheme of development. 



The Hells Canyon Reach of the Columbia River 

 and Tributary System 



In August 1955, the FPC licensed Idaho Power Company to 

 undertake a three-dam development along the Hells Canyon Reach 

 of the Snake River. (See Figure 15.) The three rock-fill dams pro- 

 posed by the company would develop the 602 feet of fall in that 

 reach. Brownlee Dam would have a maximum head of 277 feet, 

 usable storage of a million acre-feet for flood control, and an initial 

 installation of 360,400 kilowatts with provision for an additional 

 180,200 kilowatts. Oxbow Dam, downstream, would have a head 

 of 117 feet, usable pondage of 6,200 acre-feet, and an initial instal- 

 lation of 151,000 kilowatts with provision for an additional 75,000 

 kilowatts. A "Low" Hells Canyon Dam would be the third struc- 

 ture in the Idaho Power Company plan, with a head of 208 feet, 

 usable pondage of 11,200 acre-feet, and an initial installation of 

 272,000 kilowatts with provision for an additional 136,000 kilo- 

 watts. The capacity installed at the sites of the three dams would 

 therefore total 783,400 kilowatts initially, and somewhat over a 

 million kilowatts ultimately. Moreover, it has been estimated that 

 the storage provided in the Hells Canyon Reach would warrant 

 installing approximately 181,000 kilowatts of additional capacity 

 at downstream run-of-river plants.^ The present generating capac- 

 ity of the Idaho Power Company's system is 374,000 kilowatts, or 



' The data in the Hells Canyon case were drawn from the Federal Power 

 Commission's voluminous record of the case — extending from December 1950 

 to the issuance of the license in August 1955 — In the Matters of Idaho Power 

 Company; Project No. 1971, No. 2132, and No. 2133, including particularly: 

 Transcript of Hearing, Exhibits, Brief of Commission Staff Counsel, and Deci- 

 sion. For a more detailed explanation of the particular estimates selected, see 

 Note to Chapter v. The estimate of additional capacity for downstream, run-of- 

 river plants was taken from the FPC's Staff Brief, Appendix A, p. 5. We assume 

 the downstream plants to be the following (either existing, under construction, 

 or proposed) federal installations: NcNary, John Day, The Dalles, Bonneville, 

 Ice Harbor, Lower Monumental, Little Goose, and Lower Granite. 



