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-2- Meeting of September 5, 1964 The Mexican Commissioner stated that his preliminary studies of tile drains with an effluent of 4,000 parts per million may result in peak salinities of water to Mexico of about 1,500 p.p.m. 1) or higher at times, in the winter months and possibly in May and September. He advised that this may make it difficult for Mexico to accept the tile drains solution. He suggested further consideration of the "by-pass" alternative on the basis of the United States by-passing a total of 90,000 acre-feet of water, with Mexico requesting minimum treaty deliveries for only about 50 days. The Mexican Commissioner advised that he would further study tile drains in light of the data to be furnished of experience with drains in the United States in respect to pattern of return flows as related to the pattern of diversions which would have bearing on the salinity of waters to Mexico during the critical months. I agreed to again give consideration to the "by-pass" alternative as a possible solution. Meeting of September 10, 1964 I advised the Mexican Commissioner that I could not recommend the suggestion for a by-pass solution which would involve the by-passing of 90,000 acre-feet of United States waters when with Mexico's proposed diversion schedule, about two-thirds, or 60,000 acre-feet, would not be excess waters over and above treaty deliveries, and would require releases from storage in the same amount. I stated that the United States position is that it cannot agree to the by-passing of other than excess waters. I referred to the original proposal of a by-pass channel on the basis of a salt balance of 1.5:1 as offering a solution if it did not involve the by-passing of waters which could otherwise be used. There was discussed the possibility of a by-pass alternative on a basis of Mexico modifying its winter pattern to provide an increased period of minimum treaty requests - possibly 90 days or more. We agreed to consider this possibility. The Mexican Commissioner stated that he was still studying the tile drain alternative but there appeared increasing difficulties for its acceptance because salinities of 1,500 p.p.m. or more may obtain. Meeting of September 12, 1964 The Mexican Commissioner advised that his Government could not accept the tile drain solution because his studies indicated that salinities would 1) This Section's studies confirm that with 4,000 p.p.m. effluent from tile drains, the salinity to Mexico may equal or exceed 1,500 p.p.m. at times.Epson Perfection 4870 Photo, 400 dpi, 8 bit, 10,289,664 byte