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CONFIDENTIAL -5- pumped out during the summer months so far as there is a need for water during these months and, if it is not supplied from irrigation drainage, it must be released from Davis Dam. Such a release from Davis Dam would be a net loss to the United States of useable water. IV. Proposal of the Bureau of Reclamation The Department has reviewed the study of the Bureau of Reclamation on the salinity problem on the lower Colorado River entitled "Special Studies - Delivery of Water to Mexico, February 1963." The Bureau's stated purpose is to reduce the peak salts concentrations in water delivered to Mexico under the 1944 Water Treaty. Its proposal involves essentially a change in the delivery pattern for salts by reducing the salt concentrations in the peak winter months but increasing them in the summer. No material decrease would be achieved for many years in the total tonnage of salts delivered to Mexico from the Wellton-Mohawk District which is now discharging in its drainage water about 3.5 times the salt tonnage required for successful irrigation. The Bureau's proposal, by decreasing the winter peak salt concentrations, would help the minor winter crop which provides less than 20% of the agricultural income in the Mexicali Valley derived from acres irrigated by Colorado River water but, by increasing the summer salt concentrations, would adversely affect the major summer crop which provides more than 80% of the income. The combined net effect would be a substantial reduction in income and hence aggravation of the problem. If the choice is between the present situation and the Bureau proposal Mexico would therefore probably prefer the present situation. V. Recommendations 1. That the Department of the Interior discuss with the Wellton-Mohawk District a reduction of pumping for the winter of 1963-64 of 400,000-acre feet. This reduction should be coordinated with the Mexican irrigation schedule through the International Boundary and Water to achieve the maximum feasible reduction in winter salinity consistent with uses in the United States. 2. If necessary, lawyers of Justice, State and Interior should be prepared to discuss in detail with the Wellton-Mohawk Board of Directors and attorneys for the District the legal risks involved for the District and the United States unless a satisfactory solution is reached. Because our present information indicates that Mexico plans, if necessary, to press its case in the form of a suit by the Colorado River irrigation CONFIDENTIALEpson Perfection 4870 Photo, 400 dpi, 8 bit, 2,222,550 byte