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1057 in Tables 6A-6C. The quantities were computed by the methods previously des- cribed. The Oxford Farmers Ditch spillage and the Chicosa Creek flows were estimated for the months before the recorders were installed. The streamflow records of irrigation seaSOn 1970 are "provisional - subject to revision." An adjustment to the records of the Arkansas River at Catlin Dam was made by Water Conservation Board personnel to correct apparent erroneous data. There- fore, the water budget for irrigation season 1970 should be considered pre- liminary. The results are not as good as had been hoped. The total gain in ground water storage for irrigation seasons 1968 and 1969, 5,390 ac-ft and 6,260 ac-ft, seem larger than one would expect, and the total gain for irrigation season 1970, l2,6l0'ac-ft, seems much too large. Inspection of the total seepage columns in the tables reveals a lack of consistent pattern. One would expect seepage inflow to occur during the early months of the irrigation season when the river is high relative to the water table, and the opposite during the later months. Further, one would expect more loss of ground water by seepage than gain because of recharge from irrigation returning to the river. This is not shown by the tables. The reason for this inconsistency is probably the source of the errors. A comparison of the results of the water budget computations with the change in ground water storage computed from the cross sections is shown be low: Ground Water Change From Change From Ratio of Changes Storage April 1 April 1 X-Section X-Sections X-Sections Water Budget Water Budget Date (Ac-Ft) (~B-Ft) (Ac-Ft) 4- 1- 6 9 35,580 7-1- 69 39,260 3,680 6,160 0.597 9-1- 69 39,810 4,230 8,080 0.524 ll-1-69 39,350 3,770 6,260 0.602 4-1-70 37,720 7-1-70 41,050 3,330 10,200 0.326 9-1- 70 40,240 2,520 15,920 0.158 ll-1-70 39,670 1,950 12,610 0.155 The table shows that results of the water budget computations are consistently larger than those of the cross section computations. A relation between the ratios of change for irrigation season 1969 is evident but not for irrigation season 1970. This indicates better agreement between the two for irrigation season 1969 than for irrigation season 1970. Inaccuracies of the streamflow records, particularly the Arkansas River at Nepesta and Catlin Dam, probably caused the errors in the seepage determination. The hydrographs of the Nepesta and Catlin flows during irrigation season 1970 were plotted. There were times when there were differences between the two records - 17 -