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.' i 5 ~; Although the Wellton-Mohawk drainage was the primary cause ~ --J of the increase in salinity, another factor also had a significant r.o ~ impact. Beginning in 1961, releases into Mexico were sharply reduced in anticipation of storage in Lake Powell behind the newly constructed Glen Canyon Dam. This loss of dilution water can be emphasized by two figures; for the 10-year period from 1951 to 1960, the average delivery to Mexico at the northerly international boundary was 4.24 million acre-feet per year, while for the succeeding 10-year period from 1961 to 1970 the flow averaged only 1.5 million acre-feet per year. The Wellton-Mohawk drainage water and the decreased flows caused the average salinity of the waters delivered to Mexico to increase from 800 parts per million in 1960 to 1500 parts per million in 1962. Although, as previously indicated, the United States intended that Mexico must receive return flows below Imperial Dam under the Treaty, no one had anticipated return flows as high in salinity as the Wellton-Mohawk drainage or that there would be such a precipitous rise in the salinity of the waters delivered to Mexico. Consequently, after the winter of 1961-62, the United States undertook certain provisional measures to minimize the impact of the high salinity drainage returns from Well ton-Mohawk. The United States also entered into negotiations with Mexico to arrive at a practical solution. The State Department asked the governors of the seven Colorado River Basin states to appoint two members to a reconstituted Committee of Fourteen in order to advise the State Department in con- nection with the Wellton-Mohawk problem. (The current members from California appointed by Governor Reagan are William Gianelli, Director of Water Resources, and myself.)