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24 Table 4 Cont. Post-Project Conditions for the Animas-La Plata Project at Bluff, Utah WET Water Year 1949 (Units . cfs) Section 7 Animas-La Pl ata Post-Project Percent Month Baseline DeDletions Conditions Chanae October 1,435 -123 1,312 -9 November 1,278 -83 1. 195 -7 December 1,027 -77 950 -7 January 1,333 -108 1,225 -8 February 1,388 -142 1,247 -10 March 1,638 -228 1,410 -14 April 2,917 -470 2,447 -16 May 6,653 -428 6,225 -6 June 10,521 -481 10,040 -5 July 4,365 -305 4,060 -7 August 1,198 -203 995 -20 September 778 40 818 5 Project ImDacts When Project depletions are considered (Table 4), impacts occur under all conditions with further reduction in flow virtually every month. The months of April, May, June, July. and August of dry and average years displayed the greatest impact from the Project. Mean monthly flow reductions range from 7 to 32 percent in an average year (1945), and wet year reductions are in the range of 5 to 20 percent (1949). Dry years tend to reflect the most significant changes where flow reductions range between 1 and 70 percent (1951),2 2 The calculation of changes in flow between baseline and post-Project was accomplished using Reclamation's model of the San Juan River. The modeled depletions at Bluff may vary somewhat from the Animas-La Plata depletions shown in Appendix B due to reservoir and diversion operations. The model is the best available, but has some limitations and may not reflect all current operational objectives for the Navajo Reservoir, The major difference lies in the way flood releases are treated. Present operations call for releases in anticipation of spring floods, while the model does not (i.e., spills occur). The changes between baseline and post-Project were modeled as they occur in the Project operation plan and accurately reflect the change in flow expected to occur.