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I- I . ~ ~ c-.l . evaporation, precipitation in the drainage basin between Artesia and McMillan Dam, gage heights at McMillan Reservoir, and the area weighted density of the vegetative cover in the delta area, Of these only the flow at Artesia, antecedent flow at Artesia, and magnitude of the rise of the flow at A.teBia ,'ere found to be of significance, The estimates of the Pecos River effective flows at Dam Site No. 3 for 1941 and 1942 were added by extrapolation of the multiple correla_ tions: and were checked by two additional correlations. A third multiple correlation was developed for present condi- tions, i,e" the conditions that existed for the calendar years 1950 through 1953. The total Pecos River effective flow at Dam Site No, 3, for the period January 1, 1938 to December 31, 1953, excluding 1941 and 1942, was found to approximate very closely the totals obtained for this same period by use of the first two multiple correlations. This indicates that although physical conditions have chanfed in the delta area, the combination of conditions has resulted in maintaining approximately the same inflow-outflow relationship throughout the period of study. As a result, for the cOInputation of losses and salvage, the pecos River effective flow for present conditions is con- sidered to be the mean of the values obtained by the three multiple correlations. The losses that may be expected to occur in the future, from floVls passing Artesia and conveyed by the channel; were determined by establishing the relationship between the flow-duration curves of mean daily discharge for the Pecos River near Artesia and the Pecos River effective flow at Dam .site No.3. After this relationship was estab- lished, covering the period March 13, 1952 through December 31, 1953, it was then adjusted for the difference in the evaporation from the water surface of the present chalmel and ponding areas and the water surface of the proposed water salvage chmmel. The 10s0es were esti- mated to average 5,260 acre-feet annually, The losses that Inay be expected in the future due to flows in excess of water salvage channel capacity being diverted through the floodway, were computed separately for the flows transported in the essentially existing low-flow water courses and those which spread out over the floodway. Computations were made on a daily basis and include seepage and evaporation losses estimated to average 5,65c acre-feet annually, The estimated channel losses were substantiated by independent studies made by the Inter- state Stream Commission, In addition to the salvage of surface flows that would result from confining such flows to the conveyance channel and floodway, there would be salvage of groundwaters as the result of construction of the pr~posed works, Als~, there would be opportunity for salvaging some additional groundwaters thr~ugh construction of spur drains into the portions of the delta area to be protected by the contemplated levees, The limited infonlL8.tion available r>n groundwater conditions in the delta area precludes exact determination at this time of the amount of ground water that can be salvoged. The commission contem- plates initiation of a p,roundwater survey of the delta area, in coop- eration with the U,S. Geological Survey, which will establish the 8 Rev. 1-6-55