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Show would " be the Rocky Mountain trench, a natural gorge extending into northern Montana. Storage capacity of the trench would be about 507 million acre- feet. South from the trench, a further complex of canals, tunnels, and waterways could carry water to the southwest and the three northern states of Mexico. NAWAPA has been widely discussed and strongly opposed by Canadian Provincial officials. This plan was authored by the Ralph M. Parsons Company of Los Angeles. ( b) Western States Water Augmentation Concept This plan was developed to improve on the NAWAPA plan by overcoming some of the principal objections of NAWAPA. The Liard River of the MacKenzie River system would be the main supply for this plan. Water would be backed up on the Liard River channel by means of a series of reservoirs and pumps and released in the Rocky Mountain trench. The trench would be used as a conveyance route rather than a storage facility and free passage for the new water would be made on about 160 miles of existing reservoir. A large regulatory storage reservoir ( 30 million acre- feet) would be constructed in the Centennial Valley of southwestern Montana. Fanning out from the Centennial Valley, water would be fed into the upper Missouri River and the upper Snake River, with secondary branches into Nevada, Utah, and southern California. Upper Snake River water would be conducted southeastward to feed into the headwaters of the Green River. The natural channel of the Green River would be used to convey the new water to the Pacific Southwest. From the lower Colorado River water would be conveyed eastward into the Rio Grande River above Albuquerque. Eastern slope streams would also be augmented via Sweetwater River, Pathfinder Reservoir ( to be enlarged), and aqueducts flowing southward. An estimated ^ 0 million acre- feet of water annually would be provided by this plan. ( This plan was authored by Lewis Gordy Smith.) ( 2) Environmental Impacts of the Alternative The environmental impacts of projects of augmentation from other than the Colorado River Basin, have not been assessed at this time, even in general terms, because they are beyond the present time of need. d. Summary of Environmental Impacts of Alternative Sources of Water Within the Bonneville Basin Physical, economic, and environmental impacts of the alternative sources of water within the Bonneville Basin are summarized in Table H- T. 546 |