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As expected, tables 8 and 9 for the most part show minor changes between the historic period of record and the baseline period of record for Deerlodge Park, reflecting the relatively small amount of current water resource development. This is summarized in Table 11 which shows mean annual yield for the basin. The historic yield decreased by 5.8% to the present baseline condition, and decreased an additional 5.0 % to the with project condition. TABLE 11 Mean Annual Yield, Yampa River at Deerlodge Park Water Years 1941-1986 ----------------------------------------------------- Condition mean annual yield ac-ft depletions from cfs acre-feet historic baseline ---------------------------------------------------- Historic 2143 1,551,460 -- -- Baseline 2018 1,460,965 90,495 -- Project 1917 1,387,845 163,615 73,120 The decrease in mean annual total sediment yield is summarized in Table 12, and shows sediment transport decreased by 7.1% from historic to baseline, and an additional 18.3% to the with project condition. TABLE 12 Mean Annual Total Sediment Transport, Deerlodge Park Condition mean mean sediment load tons reduction from cfs in million tons historic baseline -------------------------------------------------------- Historic 2143 2.602 -- -- Baseline 2018 2.417 185,400 -- Project 1917 1.976 626,800 441,450 -------------------------------------------------------- More revealing than Tables 11 and 12 is the seasonal distribution of flow and therefore sediment transport. Examining Figures 4 and 5 shows that the increased project baseflow months transport more sediment than the lower baseline baseflow periods, but the reductions in peak flow months have resulted in a net decrease in transport. This difference is even more apparent when examining the running balance of sediment in the Deerlodge Park to Mathers Hole reach.