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Chapter 3- Description of the Alternatives <br />river water also tends to keep Basin reservoirs at a higher level, increasing the likelihood of <br />spillway releases and higher flows through the Central Platte Habitat Area. Leasing water from <br />irrigators, and the associated reduction in diversions and consumption of water by crops, is an <br />example of this approach. <br />? Retiming of flows: Flow targets far the endangered species can be achieved by shifting the <br />pattern of riverflows to times more beneficial to the species. This can be done either by <br />changing the pattern of releases from existing reservoir storage, by increasing the amount of <br />water that is stored and then later released, or by diverting riverflows into groundwater recharge <br />facilities (canals, ponds) where those waters will return to the river later through groundwater <br />return flow. <br />? Increasing the draw on existing water supplies: River flows for the species can be improved <br />by increasing the releases from existing reservoir storage, such as the release of water from <br />Environmental Accounts (EAs) in Pathfinder Reservoir or Lake McConaughy. <br />All of the above approaches are included in the action alternatives and each has some potential effect on <br />other flow uses. Reduced consumption of riverflows increases achievement of flow targets while <br />(usually) reducing agricultural production and its associated economic activity. Retiming of riverflows <br />improves target flows but changes the pattern of reservoir releases or river diversions to groundwater, and <br />may affect such activities as hydropower generation. Increased demand upon existing water supplies <br />leads to lower reservoir levels as stored waters are used to improve achievement of target flows, which <br />can in turn affect irrigation deliveries, fisheries, recreation, and power generation. This FEIS aims to <br />describe this mixture of effects and assess their impact on important resources and economic activities. <br />None of the action alternatives manages sufficient amounts of water to achieve completely the target flow <br />conditions shown in table 3-3 (species flows) and table 3-5 (annual pulse flows) that create good habitat <br />conditions for the target species. The Governance Committee Alternative, far example, would move <br />Overton, Nebraska (over the months of the year) for the Present Condition, and the Governance <br />Committee Alternative, compared to the species flows and annual pulse flow targets. Figure 3-1 shows <br />median riverflows at Overton, Nebraska (over the months of the year) for the Present Condition and the <br />Governance Committee Alternative, compared to the species flows and annual pulse flow targets. Note <br />that species and pulse flows over various water years (wet, dry, very dry) are calculated to provide one <br />comparison line for targets. See Addenda, Draft Instream Flow Recommendations.