OCR Text |
Show The background available to and considered by the Committee in arriving at the above recommendations included the facts that filling the Upper Basin reservoirs first became of paramount importance when problems related to the outlet gates at Glen Canyon Dam were made public, and it became known that pondage of about a million acre-feet of water would be necessary during construction. In order to answer questions from interested entities and to provide a basis for preparing an Annual Report to Congress under the terms of Section 6 of the Colorado River Storage Project Act, it became necessary for the U. S. Bureau of Reclamation to develop assumed criteria for a study of filling Glen Canyon Reservoir, which the Bureau called "Hydrologic Bases for Financial Analysis." These "Bases" were prepared using average flows of the river and were formally presented to representatives of all seven States of the Basin at a meeting in Washington, D. C. on October 24, 1957. During that same meeting, Lower Basin representatives introduced criteria for the long-term operation of Glen Canyon reservoir which they felt would be more appropriate. At a subsequent meeting in Las Vegas, Nevada, on December 4 and 5, 1957, the two sets of criteria were discussed. It was decided that a group of engineers of the Lower Basin would meet with engineers of the Bureau of Reclamation for the purpose of studying the technical problems related to filling Glen Canyon Reservoir. This group, known as the Lower Basin Engineering Group, held several meetings with engineers of the Department of the Interior. The Lower Basin Engineering Group modified the earlier studies of the Department, which were based on average stream flows, by preparing studies using a recorded sequence of years of stream flows. The recommendations of the Engineering Committee were approved by the Commission, and, in accordance with those recommendations, the Commission staff has devoted most of its time to engineering studies pertaining to criteria for filling Glen Canyon Reservoir. A great many assumed conditions and combinations of assumed conditions under which water might be stored in Glen Canyon Reservoir, released from Glen Canyon, stored in Lake Mead and released from Lake Mead, are being studied. Effects are being determined of the many combinations of assumed conditions on such significant items as: (a) date first power production at Glen Canyon could be expected; (b) annual and total energy produced at Glen Canyon and Hoover power plants, individually and combined; (c) date Glen Canyon Reservoir could first be filled; (d) amount of contract firm power that might be produced at Hoover and annual deficiencies in contract firm power; (e) amount of secondary power possible; (f) amount of water in storage at end of each year; (g) releases from Lake Mead in excess of downstream consumptive uses; (h) other significant hydrologic information. 20 |