Memorandum on Colorado River Salinity Problem

Memorandum: From J.F. Friedkin, Commissioner, "Colorado Salinity Problem, Analysis of Mexico's position in rejecting a "by-pass solution with salt balance of 1.5:1" but having no objection to a "tile drain solution even though resulting salinity may exceed 1.5:1", page 1INTERNATIONAL BOUNDARY AND WATER COMMISSION UNITED STATES AND MEXICO 206 SAN FRANCISCO STREET EL PASO, TEXAS 79950 August 23, 1964 MAILING ADDRESS: P.O.BOX 1859 MEMORANDUM SUBJECT: Colorado River Salinity Problem Analysis of: Mexico's position in rejecting a "by-pass solution with salt balance of 1.5:1" but having no objection to a "tile drain" solution even though resulting salinity may exceed 1.5:1. The Mexican Commissioner advises that 1) his Government would not object to a "tile drains solution" in the Wellton-Mohawk District, even understanding that the salt content of the effluent is uncertain, but 2) his Government cannot accept a "by-pass solution of 1.5 salt balance"; it must insist upon 1.0 salt balance. This would appear an inconsistent position for Mexico, understanding that the estimated annual salt content of the effluent from tile drains may be higher than that which would pass to Mexico with a "by-pass channel solution of 1.5 salt balance index". It is now estimated from the conference in Denver, August 18-20, that tile drains would result in an initial salt balance index of 1.6 to 1.9. But it may not be inconsistent from Mexico's point of view, when it is recognized that Mexico's concern and effort is to protect its water rights under the treaty in the light of its experience over the past three years: 1) In 1961 the waters of the Colorado River delivered to Mexico pursuant to the 1944 Water Treaty, increased from about 900 p. p. m. to a peak of 2,700 p. p. m. and the total tons of salt to Mexico more than doubled. This change occurred without warning to or prior consultation with Mexico. 2) It soon became apparent that the cause of the increase in salinity was the pumping of 6,000 p. p. m. waters from the highly saline aquifer underlying the Wellton-Mohawk District at depths of 40 to 100 feet. These waters were not the direct return flows from irrigation which would average about 2,300 p. p. m. 3) Soon after the facts were evident in 1961, Mexico took the position and has consistently maintained that it will accept direct return flows, but that the pumped waters are not direct returns from irrigation, and that Mexico will not accept pumped waters as a substitute for return waters.Epson Perfection 4870 Photo, 400 dpi, 8 bit, 3,138,468 byte