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Show CHAPTER VI 107 G. Promulgation of Principles and Additional Regulation No. 1 The general principles and operating criteria, as approved April 2, 1962, were published in the Federal Register, 27 F.R. 6851, July 19, 1962. Additional Regulation No. 1 was adopted by Secretary Udall on July 12, 1962, and published in the Federal Register, 27 F.R. 6850, July 12, 1962. The texts thereof appear in appendices 602 and 603, respectively. H. Closure of Glen Canyon Dam The partial closure of Glen Canyon Dam was accomplished at 2 p.m. on March 13, 1963, at which time the Bureau of Reclamation's Lower Colorado Regional Office at Boulder City, Nevada, began computing the "deficiencies." At that time, Lake Mead held 22.3 maf of water at elevation 1188.2 but this dropped to 15.4 maf at the end of January 1964. As of September 30, 1963, the deficiency was about 75 million kWh. By the end of 1963, the elevation of Lake Powell was about 3410 (80 feet short of minimum power point (3490)) with a content of 3.1 maf and, in addition, the runoff forecasts for 1964 indicated another poor runoff year. Studies at that time showed that to avoid drawing Lake Mead below elevation 1123, it would be necessary to release in 1964 the water theretofore impounded in Lake Powell. (For a discussion of an engineering analysis of the risks involved in closing the gates of Glen Canyon, see the Chief Engineer's memorandum to the Commissioner of Reclamation dated August 14, 1963.) The gates were opened temporarily on March 26, 1964, to maintain elevation 1123 at Lake Mead (14.5 maf storage). This was done because the March 1, 1964, forecast of a poor runoff indicated too great a risk of substantial expense to the Upper Basin if the April-July runoff turned out to be substantially less than the then mean forecast of 4.7 maf (News Release - Interior, May 11, 1964). The determination to open the gates was in accord with the filling criteria of 1962, particularly Principle 7, which provided that Lake Mead would not be drawn down below elevation 1123. Prior to the Secretary's action in opening the gates at Glen Canyon on March 26, 1964, the Governors of the four Upper Basin States in a joint letter of March 17, 1964, urged the retention of water in Lake Powell in order to start generation of energy by August 1, 1964, and stressed the need to arrive at a method of filling the minimum power pool at Glen Canyon at the earliest practicable date. The Upper Colorado River Commission actively explored with various utilities in the Upper Basin the possibility of obtaining energy to supply deficiencies in the Lower Basin in the event Lake Mead was drawn below elevation 1123. On March 25, 1964, the Colorado River Board of California protested the withholding of water in Lake Powell as did Governor Brown of California. /. Modification of Filling Criteria - May 11, 1964 The median forecast of May 1, 1964, for April-July runoff was 5.1 maf. Hence, the Secretary announced on May 11, 1964, that storage of water would be resumed behind Glen Canyon Dam and that "the calculated risk...in resumption of storage is warranted...." The gates were again closed May 11, 1964, at which time the Secretary modified the 1962 filling criteria to reduce by 40 feet, from elevation 1123 (rated power head) to elevation 1083 (minimum power pool) the water level below which Lake Mead would not be drawn by reason of the accumulation of minimum power operating content in Lake Powell, 6.1 maf, and elevation 3490. The Secretary provided certain conditions to be observed upon the resumption of filling operations at Lake Powell which caused Lake Mead to be drawn below elevation 1123. The most significant condition was that, in addition to the allowance for deficiencies in firm energy generation pursuant to the 1962 filling criteria, the United States would replace impairments in Hoover Powerplant capacity and energy available to the allottees which result from the lowering of Lake Mead below elevation 1123 by reason of storage of water in Lake Powell. The United States would also relieve the allottees of costs of extraordinary maintenance of the turbines and generators resulting from such lowering. Energy and capacity deficiencies resulting from operation below elevation 1123 were identified as impairment energy and impairment capacity. The cost of replacing the deficiencies in capacity and energy and the costs of extraordinary maintenance were to be charged to the |
