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<br />001994 <br /> <br />Example Depletion and Diversion Calculations for RiverWare node <br />AboveJacksonGulch _ IrSurn, October, 1971. <br /> <br />Depletion Request = depletion percent of 34-5149, HUe combination 1 (0.0426) <br />. HUe 14080107 livestock. depletion (24.0) <br />+ depletion percent of 34-5149, HUC combination 2 (0.0426) <br />. HUC 14080107 stockpond depletion (32.0) <br />+ depletion percent of 34-5600, HUe combination I (0.5) <br />. HUe 14080107 small reservoir evaporation (4S.0) <br />+ depletion percent of 34-5609, HUe combination 2 (0.0084) <br />. HUe 14080t01livestock depletion (24.0) <br />+ depletion percent of 34-5609. HUe combination 2 (O.OO84) <br />. HUC 14080107 stockpond depletion (32,0) <br />= 27.73 acre-feet. <br /> <br />DiversioD Limit = huc""pcrcenl of 34_5149. HUe combination 1 (O.S. capacity of 34_5149 (4.84 efs) <br />+ huc""percent of 34_5149, HUC combination 2 (O.S). capacity of 34_5149 (4.84 era) <br />+ huc""pcrccnt of 34_5600, HUe combination 1 (1.0). capacity of 34_5600 (5.00 cfs) <br />+ buc...,pcrcent of 34_5601, HUe combination 1 (0.5). capacity of 34_'609 (1.86 cfs) <br />+ huc"pcrcent of 34_5601, HUe combination 2 (0.5). capacity of 34_S609 (1.86 cfs) <br />= 11.70 cCs = 719 acre.fcct. <br /> <br />Diversion Request = Minimum (Diversion Limit (719), Depletion Request (27.73) <br />I Weighted Minimum Efficiency (0.65 <br />= Minimum (719, 42.61) = 42.61 acre-feet. <br /> <br />Return Flow Lag Adjustment <br /> <br />The monthly natural flows were calculated by adding historical depletions back to the gage flow. <br />Any return flows appearing at the gauges are implicitly lagged. However, when depletion and return <br />flows are used which are different from those assumed in the original natural flow calculations, then <br />lagging of return flows becomes important. The San Juan Model calculates the return flows at each <br />node, but assumes the return flow reenters the river in the same month. When the return flow from <br />any model run is greater than that from a historic run, the excess return flow can be lagged by using <br />a dummy gain/loss node (Object) immediately downstream of return flow. This technique was applied <br />to three sites on the Animas and the San Juan Rivers and is explained below. Simulated changes in <br />return flows above Navajo Dam were not considered an issue because of the relatively large storage <br />capacity of Navajo Reservoir which dampens the effect of return lag. For simplicity of <br />implementation the return flows were combined at the following sites: <br /> <br />. San Juan above Farmington - Citizens Ditch and Hammond Project <br />. Animas above Farmington - Farmers Mutual Ditch, Farmington Return Flow and Minor <br />Return flows below Cedar Hill <br />· San Juan below Farmington - Cherry Creek, below the state line gauge on the La Plata, <br />Jewitt Valley, Fruitland, Hogback and Cudei <br /> <br />The 1929-1993 baseline return flows and 1970-1993 historic return flows were compiled for each site <br />from the two model runs. The historic monthly return flows for 1929-1969 were estimated by <br /> <br />DRAFT. SJRIP Hydrology Model Documentation <br />June 18, 1999 <br /> <br />55 <br />