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CONFIDENTIAL - 5 - The understanding was confirmed with Mexico, as was set out in earlier provisional papers covering exchange of views, such as the paper dated November 10, 1964, that the total amount of salts discharged from the Wellton-Mohawk District and delivered to Mexico during the summer months (March through September) would not exceed the total amount delivered in the summer months of 1964, and that this amount would decrease as the salinity of the effluent from the District drainage wells and tile drains decrease. Mexico's agreement in this Recommendation that we could pump the more saline wells in the winter period October 1 to February 10, a total of 135 days, was a concession on its part to meet the practical requirement of the United States of having as long a period as may be obtained in which to pump the more saline wells in the winter, in order to be able to pump the better wells as long as possible in the summer. This concession will require that Mexico either a) extend its requests for the minimum winter rate of Treaty deliveries of 900 cfs to 135 days; or b) on the days that it requests more than 900 cfs, but less than about 2000 cfs, waste and lose up to 300 cfs of its guaranteed Treaty waters by the discharge of Wellton-Mohawk drainage waters below Morelos. The Mexican Commissioner considers that his country may lose 20,000 to 30,000 acre-feet per year from its guaranteed waters by this concession. The further agreement by Mexico in Recommendation 6 that the United States pump the most saline wells during other periods when the total quantity of Wellton-Mohawk drainage waters is discharged below the dam, contemplates that at times during the summer periods when deliveries are low, Mexico will not request that Wellton-Mohawk waters be discharged above the dam. They would be discharged and wasted below the dam, and Mexico would accept the reduced treaty deliveries above Morelos Dam, in order to reduce the salinity of waters diverted for irrigation at that point. Mexico may lose an additional 10,000 acre-feet per year or more from its guaranteed allotment by this provision. This would provide further additional time for the pumping of more saline wells in the Wellton-Mohawk District during the summer months, in order to pump the better wells at other times. Recommendation 7 originated with Mexico, with a view to avoiding, after the completion of the bypass channel, discharge of Yuma Wasteway waters to the bed of the river below Morelos Dam to mix with the high saline drainage waters of the District. Mexico requests that the wasteway waters be discharged at San Luis with the Yuma drainage as a part of the Treaty waters. This was discussed at the Mexico City meeting only with respect to the word "should", in the first line of the 1/12/65 draft. Mexico requested that the statement that "the United States should conclude arrangements to discontinue discharge of Yuma Wasteways to the bed of the river below Morelos", not be a conditional statement. The United States position was that the works are under the control of an independent irrigation district, and that we could not commit that district to any arrangement without its prior consent. We could only agree to make every effort to conclude such an agreement. The understanding was reached to substitute the word "endeavor" for "should". CONFIDENTIALEpson Perfection 4870 Photo, 400 dpi, 24 bit, 10,873,344 byte