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28 RELEASE OF COLORADO RIVER WATER above the international boundary line and at a point where they could not be again diverted or stored in the United States. It was obvious that these return flows would reach the river and pass into Mexico without control. The consideration of these two factors were dominant in fixing the amount and in avoiding any commitment as to the quality of water which Mexico would receive under the treaty. At that time, it was estimated that with full development in the United States, the return flows would approximate 1 million acre-feet per year. Predicated upon this assumption, the negotiators for the United States agreed that they would recommend that Mexico be given 1 1/2 million acre-feet per year, if Mexico would agree to accept for credit upon the treaty all of the return flows and would would abandon its request for guarantee as to quality. This solution was agreed to by the negotiators of both countries and the treaty was so drafted as to implement the agreement. In article 10 of the treaty, referring to the water to be received by Mexico, the language provided in part that Mexico's share would be from waters of the Colorado River, "from any and all sources." Article 11 provided that delivery of Mexico's water would be made from waters of the Colorado River "whatever their origin." In transmitting the treaty to President Roosevelt and recommending its execution, Cordell Hull, the then Secretary of State, in referring to the quantities of water to be delivered to Mexico stated "These quantities, which may be made up of any waters of the Colorado River from any and all sources, whether direct river flows, return flows, or seepage, will be delivered by the United States in the boundary portion of the Colorado River * * *." In 1945, the U.S. Senate Foreign Relations Committee held extensive hearings in which I participated personally. Two States were opposing ratification of the treaty. The United States and the other five States were strong proponents of ratification. The question of the quality of the water which Mexico would receive was diseussed extensively. A witness for the State Department, Mr. Frank Clayton, was at that time the legal counsel for the U.S. Section of the International Boundary and Water Commission, and one of the treaty negotiators for the United States. In answer to a question, Mr. Clayton stated as follows: "Now, to get back to the words 'from any and all sources' and 'whatever their origin,' those words were inserted by the American representatives in this Treaty to insure that the United States would get credit for all kinds of water, whether it was green water or clear water or any other kind of water, whether drainage or fresh, that actually found its way to Mexico, that might come into the main stream, in the boundary portion, from Arizona, for instance, but still the United States would be entitled to credit for it." In addition to this witness, there were numerous others, all of whom stated clearly that there was no guarantee of quality of water to Mexico. It was only upon this understanding that the Senate ratified the treaty. Without this understanding the treaty would not have been ratified. It is essential to emphasize that there are still many major projects, many of which have been authorized by Congress and others which will be presented to Congress, to be constructed in the Colorado River Basin States. These projects will all contribute additional return flows to the river system and will tend to create a further deterioration in the water quality. The development of these projects in the United States was foreseen and anticipated by the various provisions of the Mexican treaty referred to above. The full utilization of the Colorado River, just as is the case on all other rivers in arid areas, is predicated upon the use and reuse of water from the headwaters of the river to the point of its final discharge in the sea. Water is diverted, applied to the land, and the excess water over and above that required by the crops, returns to the stream. The water returning to the stream brings with it salinity from the soil through which it passed plus the residual from the original water remaining after evaporation and transpiration on the cropped area. This is a continuing process as the river flows downstream. It has been suggested by Mexico that the current problem is created by one project in one State. The return flows and the resulting salinity about which Mexico has currently protested, reach the river just above the international boundary line. It is further aggravated by the fact that Mexico voluntarily chooses to follow a cropping pattern which requires most of her water to be delivered during 7 months of the year. Hence, there is little opportunity during the other 5 months of the year for the dilution of these return flows. Return flows from other projects located upstream have an opportunity to mix with theEpson Perfection 4870 Photo, 400 dpi, 8 bit, 1,811,973 byte