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Show 220 UPDATING THE HOOVER DAM DOCUMENTS The agreement was incorporated in Minute No. 242 of the International Boundary and Water Commission dated August 30, 1973, which also terminated Minute No. 241 (see Appendix No. 1303 for text of Minute No. 242). F. Minute No. 242 The major provisions of Minute No. 242 are: (1) The United States shall adopt measures to assure that by no later than July 1, 1974, the waters delivered to Mexico upstream from Morelos Dam will have an average annual salinity of not more than 115 p/m, plus or minus 30 p/m, over the annual average salinity at Imperial Dam. This quality guarantee becomes effective upon authorization by Congress of the funds to construct the "necessary works." (2) Until Congress authorizes the necessary works to provide the quality guarantee, the United States shall continue to bypass Wellton-Mohawk drainage water at the annual rate of 118,000 acre-feet per year, without charge against Mexico's Treaty allotment, and substitute therefore an equal volume of better quality water. (3) The United States will continue to deliver approximately 140,000 acre-feet of water to Mexico on the land boundary at San Luis, Mexico, in partial satisfaction of the 1.5 maf/yr Treaty requirements, with a salinity essentially the same as that of the waters customarily delivered there (approximately 1,500 p/m). (4) The existing concrete-lined Wellton-Mohawk drain shall be extended approximately 53 miles to Santa Clara Slough (on the Gulf of California) with a capacity of 353 cubic feet per second, the same capacity as the existing drain. Construction and operation in Mexico would be performed by the Mexican Government, but at the expense of the United States. (5) Pending the conclusion by the two governments of a comprehensive agreement on ground water in the border areas, each country shall limit pumping of ground waters in its territory within 5 miles of the Arizona-Sonora boundary near San Luis to 160,000 acre-feet annually. (6) The United States will support efforts by Mexico to obtain appropriate financing for improvement and rehabilitation in the Mexicali Valley. The United States will also provide nonreimbursable assistance for those aspects of the rehabilitation program relating to the salinity problem, including tile drainage. The extent of the participation is to be negotiated later. (7) The new Minute is to be recognized as a permanent and definitive solution to the Colorado River salinity problem. G. United States Actions Under Minute No. 242 Although not spelled out in the Minute, the Administration stated that the following "measures" would be undertaken to comply with Minute No. 242: (1) Construction of a major desalting plant and appurtenant works to treat the Wellton-Mohawk drainage waters, scheduled to be completed in December 1978. (2) Extension of the Wellton-Mohawk drain by 53 miles to the Gulf of California. (3) Lining or construction of a new Coachella Canal in California. (4) Reduction in Wellton-Mohawk irrigable acreage from the 75,000 acres authorized in the Gila Reauthorization Act to 65,000 acres, and improved Wellton-Mohawk irrigation efficiency so as to reduce the quantity of "return flow" drainage water to the river. G.I Yuma Desalter A major objective of the program was that the Wellton-Mohawk drainage waters would be reduced from approximately 220,000 acre-feet per year to approximately 178,000 acre-feet per year. The reverse osmosis desalting plant would treat approximately 143,000 acre-feet per year of that 178,000 acre-feet. The resulting 100,000 acre-feet per year of product water would be mixed with the 35,000 acre-feet of untreated Wellton-Mohawk water to produce a blend of water returned to the river for delivery to Mexico which then will have an average annual salinity of not more than 115 p/m plus or minus 30 p/m over the annual average salinity |