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. .~ l\j l\j U! . . HISTORY OF WATER RESOURCE DEVELOPME};"T the same volume as in 1960, the salinity at the NIB would have been less in 1961. Since the flow in 1961 was less by 800,000 acre-feet than in 1960, a larger salinity differential was observed resulting in a water quality of nearly 1400 mg/l at the NIB. The reduced flow was caused by two things. a lower than normal runoff in the Upper Basin and the filling of upstream reservoirs in the anticipation of the closure of Glen Canyon Dam. Approximately 75 percent of the rise In the salinity at the NIB was caused by the Well ton-Mohawk Drainage returns. The remaining 25 percent was caused by the reduction 1n the excess deliveries to Mexico. The increase in salinity resulted in negotiations between the United States and ~exico. In ~~rch 1965, Minute No. 218 was signed and approved by the two Governments. Beginning on November 16, 1965, Well ton-Mohawk drainage flows were bypassed around Morelos Dam during periods of minimum flow which amounted to about 55,000 acre-feet per year. The minimum flow of 900 c.f.s. at the NIB occurs during the winter months for a period not to exceed 180 days. This agreement was in effect until June 3D, 1972, and reduced the average annual salinity of waters delivered to Mexico to about 1,245 mg/l. On July 14, 1972, another agreement, Minute No. 241, was entered into. This Minute provided that the United States would increase the bypass of Well ton-Mohawk drainage, without charge against scheduled Treaty deliveries to Mexico. to the annual rate of 118,000 acre-feet and substitute equal volumes of other waters of better quality to be dis- charged to the Colorado River above ~orelos Dam. This would reduce the salinity of waters delivered to Xexico by an estimated 100 mg/l. Minute 241, with three extensions, was in effect from July I, 1972, through December 31, 1972. Minute ~o. 242 In keeping with President ~ixon's objective to find a permanent, definitive, and just solution to the salinity problem with Mexico, accord was reached on August 3D, 1973, with the execution of Min- ute 242 of the International Boundary and Water Commission. The Minute was developed following an intensive study of the problem by former Attorney General Herbert Brownell and a federal Task Force appointed to assist him. Participation of the Basin States was sought by Mr. Brownell and representatives of the Governors (identified as the Committee of Fourteen), assisted in defining the solution. The key elements of the agreement were: "1. Referring to the annual volume of the Colorado River waters guaranteed to Mexico under the Treaty of 1944, of 1,500,000 acre-feet (1,850,234,000 cubic meters): 2,