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I I I I I I I I I I I I I I I I I I I Conclusion.-Assummg these modifications depict water usage 10 years in the future, model results show t}:lat water supplies can be made and flow recommendations can be met when compared with the 1929-93 hydrology when minimum allowable releases are increased from 250 to 350 cfs during the months of May-October. General Data The following graphs depict typical wet, average and dry year conditions for the San Juan River at Archuleta, Farmington and Four Corners, and the Animas River at Farmington comparing the flows resulting from implementation of the Preferred Alternative (250/5000) to the No Action Alternative. The graphs were developed from model simulations of the system for the two conditions. In each case, two years were chosen to represent each of the conditions. The two dry years were selected from the lowest 10 percent of the years, the average years were selected from the middle 10 percent of the years, and the wet years from the wettest 10 percent. The model simulations represent hydrologic conditions from the 1929-1993 water year period. The San Juan River at Archuleta graphs demonstrate how operating Navajo Dam to implement flow recommendations will alter releases patterns. In dry conditions, spring peak releases would probably not be required, and the minimum release of 250 cfs might not be adequate to support target base flows in the recovery reach of the river. Under average conditions, lower releases can be expected during the non-spring release period. During spring release times, releases would be substantially larger than under the No Action alternative. In wet years, releases needed to evacuate flood storage space will be attempted to be made during the spring release period. Graphs of the Animas River at Farmington show the impacts of the modified Animas-La Plata Project. Graphs of the San Juan River at Farmington and Four Comers generally show that flows will be higher during the spring peak release and lower the remainder of the time. Three graphs show a frequency distribution of monthly Navajo Reservoir releases for each alternative. Releases are sorted by month and ranked in ascending order. Also shown are the end-of-month contents and water surface elevations of Navajo Reservoir for each alternative. A frequency distribution of end-of-month contents is shown in one graph and the three remaining time series graphs depict end-of-month water surface elevations with each alternative compared against the historical elevations. B-3