United States-Mexico Water Agreements and Related Water Use in Mexicali Valley: A Summary

Abstract

A summary is given of interrelated, technical and institutional events concerning the Colorado River which took place between the United States and Mexico from 1849 to 1974 with emphasis on the 1961-1974 period. Until the treaty of 1944, Mexico had had no guarantee of a specific annual quantity of water, but in the years after 1945, when a guarantee of 1.5 million acre-feet per year was established, more than that amount was available for use. Salinity problems arose, and in 1965 an agreement for a 5-year plan for alleviating the technical and political difficulties surrounding the salinity question was made. In 1973 it was agreed that the United States would build, within approximately 5 years, a facility for desalting the saline drainage water entering Mexico. Fulfillment of the technical provisions for this agreement requires, in any event, the timely provision of federal funds to construct and operate the physical works. The several states should receive assurance that their rights and those of their respective water users will not be impaired within the legal operation of the agreement.