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IS Supra. note 2, at 7. 4 <:> (M) l)) 'tv of Wellton-Mohawk drainage on the quality of waters delivered to Mexico, the draft report states: While the salt concentration of the ground water in the [Wellton-Mohawk] aquifer varies horizontally from place to place and tends to increase with depth, the mean concentration of water pumped from the aquifer is about 6,000 p.p.m. At current pumping rates, the corresponding annnal amount of salt dis- charged to the Colorado River from the project is nearly four times the amount of salt contained in the total volume of irrigation water diverted to the project. The almost continuous pumping, and discharge of the ground water into the Colorado River at the rate of approximately 300 cubic feet per second since September 1961 has had a marked influence on the salt content of the water delivered to Mexico at the northcrly boundary. 'fhe salt content increased from less than 1,000 p.p.m. in prior years to about 2,600 p.p.m. in the winter of 1961-62. In the summer months the salinity is expected to increase to range from 1,300 to 1,800 p.p.m." . . In order to improve the quality of water delivered to Mexico under the treaty, the United States panel recom- mended basically the construction of a lined by-pass channel extending from the outlet works of the Wellton- Mohawk project drainage conveyance channel past Mexico's Morelos Dam (where water is diverted for. irrigation) to a point below the dam. Additionally, the United States panel recommendcd the construction of a lined conveyance chamlel to parallel the existing' drainage conveyance channel on the vVellton-Mohawk projcct and also the construction of additional drainage wells. Water pumped from drainage wells and displaying greater salinity would under this recommendation be conveyed to the Colorado River at a point below Morelos Dam and thus would not be credited to the United States as treaty ......,.......__",_--..._-< .__~~M'.,,"_.__"'" U" , .--,.,',