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Modeling of Nebraska's Depletions <br />Nebraska's first increment depletions were modeled by reducing gains in five reaches of <br />the Platte River. The North Platte-Brady, the Brady-Cozad, the Cozad-Overton, the <br />Overton-Odessa, and the Odessa-Grand Island gains were each reduced by 4.2 kaf per <br />year (4.2/12 = 0.35 kaf per month) for a total reduction of 21 kaf (5*4.2) per year. The <br />reduced gains were used in the Program Alternative Scenario 2(PA2) run. This reduced <br />the score from 144.0 to 132.5 kaf or a difference of 11.5 kaf, which is close to Nebraska's <br />estimated first increment depletions of 12 kaf. <br />The projects identified in the WAP to meet Nebraska's future depletions are ground <br />water management, power interference, a central Platte reregulatory reservoir, and the <br />Gothenburg/Dawson recharge project. The Gothenburg/Dawson recharge project is not <br />modeled in the Opstudy model so it is excluded from this analysis. Nebraska's future <br />depletion plan was implemented by setting the three projects that are in the Opstudy <br />model at their future depletions levels (removing limits on power interference, setting the <br />size of the reregulatory reservoir to match the WAP, and increasing the amount of water <br />regulated by ground water recharge). <br />In addition, the inlet and outlet capacity of the central Platte reregulatory reservoir were <br />increased from 100 cfs and 50 cfs respectively to 200 cfs. <br />These changes result in a score of 144.3 kaf or a difference of 11.8 kaf, which meets <br />Nebraska's first increment depletions of 12 kaf when 800 af of additional benefit from <br />the GothenburglDawson recharge project is added to the score. <br />In addition to Nebraska's future depletions, 150 af was added for first increment federal <br />depletions. 50 af per year were removed from the flows above McConaughy, flows at <br />Julesburg, and the Cozad-Overton gain. <br />Julesburg flows that represent Colorado's future depletions (described previously) were <br />used to represent flows from the South Platte River. <br />The attached Excel spreadsheet summarizes changes to key model outputs on an average <br />basis, and on an irrigation season and non-irrigation season basis.