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'::'; , oaonsa WA'l'ER SUPPLY FOR THE SAN JUAN-,ClIAMA PROJECT 15 I will next discuss briefly the demands on the Navajo Reservoir. There was no appreciable discrepancy in any of the studies with respect to the demands on Navajo Reservoir for the initial phase of the San Juan-Chama project, for the Navajo Indian irrigation project, for the Hammond project, and for evaporation losses which together total about 675,000 acre-feet, The Bureau study indicated an addi- tional demand of 20,000 acre-feet annually for regulatory losses and natural flow uses below Farmington and it is this allowance which would benefit the Animas-La Plata project, The Bureau study showed spills averaging 215,000 acre-feet annually which is an indi- cation of the amount available for future use. Mr. Reynolds' study assumes that return flows and tributary in- flow below Navajo Dam will meet regulatory losses and natural flow uses below Farmington and there is no. demand included for these purposes. He includes a demand for 224,000 acre-feet annually for future municipal and industrial uses. Because of this large M. & 1. demand assumed, his study indicates shortages which he says are" tolerable" whereas the Bureau's demands are all met short- age ..jree. The Colorado Water Conservation Board Study A-I assumes not only the 224,000 acre-feet demand for future municipal and industrial supply but also 96,000 acre-feet for other Indian uses arid assumes an allowance of only 100,000 acre-feet annually for usable return flows. The Upper Colorado River Commission study indicates that for the critical period 1942"-56, the reservoir would yield 756,000 acre- feet of shortage-free water which would meet the needs of the initial phase of the San Juan-Chama project, the Navajo Indian irrigation project, the Hammond irrigation project and leave an additional 126,500 acre-feet annually available for future use, The Colorado Water Conservation Board Study A-I was a special purpose study and in my opinion no consideration should be given to it, I consider that the Upper Colorado River Commission study, because it is bas~d on the critical period of record, is too conservative, In my opinion, the conclusions of the Bureau's study and New Mexico's study by Mr, Reynolds are entirely supportable and the available water supply which they indicate can reasonably be expected. In summary, I can reasonably conclude that, on the basis of the most critical period of flow of record, there will be sufficient water available from the Navajo Reservoir, on a shortage-free basis, after making allowance for present uses in the basin and the requirements of potential developments in Colorado, to meet the requirements of the initial phase of the San Juan-Chama project, the Navajo Indian irrigation project, a,nd the Hammond project, and leave at least 126,000 acre-feet available annually for future use, from which could be. made releases to satisfy present New .!'vIexico uses that otherwise would constitute a legal demand on the flows of the Animas River, Studies indicate that the amount available for future use could be increased to around 225,000 acre-feet by taking shortages considered to be tolerable during certain critical periods. These conclusions are from the standpoint of physical operation and must be examined in relationship to New Mexico's expected entitlement, and this is done hereinafter. ~_.:,4;!