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<br />001933 <br /> <br />Another step completed in the mapping process was writing of scripts using the database utility that <br />helped insure that mapped acres equaled unit depletions and mapped nOD irrigation depletion percents <br />summed to unity. A report was also developed that tables all diversions and depletion mappings and <br />associated data for all RiverWare nodes. Output of report pnjoin.txt is shown in Appendix F. Most <br />of the terms were discussed above. Project type determines which flow capacity (direct flow right <br />verses estimated capacity) is used when checking computed diversion request against capacity. <br />Huc -percent is what portion of a station's flow that is represented by a given Hue combination. <br /> <br />The preprocessor used the mapping and appropriate depletion volumes or rates to compute depletion <br />and diversion requests by node. If a non irrigation diversion, it computed depletion request as a <br />function of diversions and depletion categories mapped to the node. Then the preprocessor computes <br />diversion requests as a function of depletion requests and a constant efficiency. If an irrigation node, <br />the preprocessor computes weighted evapotranspiration rates and total irrigated area of all diversions <br />and mapped depletion units. It also computes weighted incidental loss rate, minimum efficiency, and <br />maximum efficiency. The preprocessor is discussed in detail in San Juan RIP Hydrology Model <br />User's Manual. <br /> <br />Example calculations of one RiverWare irrigation node and one RiverWare non irrigation node are <br />provided as follows: <br /> <br />Irrigation Node Depletion & Diversion Request Example <br /> <br />Depletion Request = <br /> <br />Acres of station 34_,1141, HUC combination 1 (335.84) <br />. Evapotranspiration rate of Unit 10 (0.03.50.5 af/a) <br />. (1.0 + incidental loss rate (0.07)) <br />+ Acres of station 34_5601, HUe combination 1 (66.23)) <br />. Evapotranspiration rate of Unit 10 (0.03.505 afla) <br />. (1.0 + incidentalloas rate (O.O?)) <br /> <br />= 12..59 + 2.48 = IS.01 8cre~feet. <br /> <br />Total Acres <br /> <br />= <br /> <br />33.5.84 + 66.23 = 402.07 acres <br /> <br />W.,;gbted Rate <br /> <br />(0.03505 . 335,84 + 0,03505 . 66,23) <br />I (Total Ac"," (402,07)) <br />= 0.03.50.5 acre.feetlacre. <br /> <br />Diversion Limit <br /> <br />= <br /> <br />huc..pcrcent of 34_.5141. HUC combination 1 (1.0) <br />. capacity of 34_.51.51 (8.84 efs) <br />+ huc..,pcrcent of 34_.5601. HUe combination 1 (1.0) <br />. capacity of 34_51.51 (1.79 ers) <br />= 10.63 efa = 653 acre-feet. <br /> <br />Dh'eniou Request = <br /> <br />Minimum (Divenion Limit (653) , <br />Dcplctioo Requ... (15,07) <br />I Weighted Minimum Efficiency (0.4) <br />= Minimum (653, 36.68) = 36.68 acre.feet. <br /> <br />Note that pre-processed data populated in RiverWsre node are total node acres, total capacity, weighted evapotranspiration <br />rate, weighted efficiencies, and weighted incidental loss rate. <br /> <br />If sprinkler evapon.tion is involv~, additional test and adjustments are done as shown on Figure 6.]. <br /> <br />DRAFT - SJRIP Hydrology Model Documentation <br />June 18, 1999 <br /> <br />54 <br />