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Zeutschel OS7000, 400 dpi, 8 bit, 7,376,316 bytesThe estimated construction cost of the proposed Navajo Indian irrigation project is about $135 million at January 1958 prices. Operation, maintenance, and replacement costs are estimated to average about $481,000 annually at January 1958 prices for both 60-year and 100-year periods of analysis. The benefit-cost ratio for the project would be 0.64 to 1 on the basis of direct irrigation benefits only, and 1.44 to 1 on the basis of total irrigation benefits. The appraisal of annual economic costs includes the $2 per acre-foot depletion charge of the storage project assigned to all participating projects for all benefit-costs ratio purposes.As provided by sections 4 (d) and 6 of Public Law 485, 84th Congress (70 Stat. 105), authorizing the Colorado River storage project and participating projects, in the event that the Navajo participating project is authorized, payment of costs allocated to irrigation of Indian-owned, tribal or restricted lands within, under, or served by such project within the capability of the land to repay is subject to the Act of July 1, 1932 (47 Stat. 564); the costs beyond the capability of such lands to repay are to be determined and, in recognition of the fact that assistance to the Navajo Indians is the responsibility of the entire Nation, shall be nonreimbursable.The proposed plan of development for the San Juan-Chama project is designed to improve and stabilize the economy of the water deficient Rio Grande and Canadian River Basins of New Mexico by providing supplemental water to meet rapidly increasing needs. This would be accomplished by diverting water from the upper tributaries of the San Juan River. The water would be used for supplemental irrigation, for replacement of watershed depletions in the Rio Grande Basin, and for an additional supply for municipal, domestic, and industrial purposes. Recreation and the preservation and propagation of fish and wildlife would also be purposes of the project. On the basis of January 1958 prices, the estimated construction cost for the project facilities studied in the plan of development is about $149 million. The evaluated total annual benefits for such a development would exceed the estimated annual costs in a ratio of about 1.7 to 1.The proposed plan for initial stage development of the San Juan-Chama project, as recommended by the State of New Mexico, contemplates an average annual diversion of about 110,000 acre-feet from the San Juan River for utilization in the Rio Grande in New Mexico. The imported waters would be used for an additional municipal and industrial water supply (57,300 acre-feet) for the city of Albuquerque; a supplemental irrigation water supply (30,100 acre-feet) to about 39,300 acres of land in the Cerro, Taos, Llano, and Pojoaque tributary irrigation units in the Rio Grande Basin in New Mexico; and supplemental water (22,600 acre-feet) for irrigation of about 81,600 acres of irrigable land in the existing Middle Rio Grande Conservancy District. Recreation and the preservation and propagation of fish and wildlife would also be purposes of the initial stage of development.The proposed plan of development for the initial stage would involve three major elements; namely, diversion facilities (diversion dams and conduits), regulation facilities (Heron No. 4 Dam and Reservoir, and enlargement of outlet works of the existing El Vado Dam), and water-use facilities (principally for the tributary irrigatio