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Lake McConaughy, Lake Ogallala, Johnson Lake, Lake Maloney, Jeffrey Reservoir, and at <br />the projects' other impoundments and canals. In association with the foregoing, the projects <br />also provide fish and wildlife habitat in the projects' reservoirs and canals, and regional <br />groundwater recharge. The general objective of the Districts' current operating regime is to <br />maximize storage for irrigation purposes as a first priority while using as much of the <br />released storage water and diverted natural flow as possible for power production. Lake <br />McConaughy is the projects' major storage facility and provides the means to store water to <br />meet the multiple operating objectives of the projects. <br />During the irrigation season (April through September), it is the demand for irrigation water <br />that generally dictates the releases of water from Lake McConaughy, and the diversion of <br />water at the Keystone, Korty, and Central diversion dams. Water is released past the <br />Keystone Diversion Dam into the North Platte River to satisfy the natural flow rights of <br />downstream irrigators and provide supplemental irrigation water in accordance with <br />Central's contracts. Generally, all flow in the South Platte at Korty is diverted to the <br />Sutherland Canal. To satisfy the needs of irrigators served by the E -65, E -67, Phelps <br />County, and Supply Canal systems, water is diverted at the Central Diversion Dam and <br />delivered via the Central Supply Canal. Diversions in excess of these irrigation needs are <br />returned to the river via either the Jeffrey Return or the Johnson No. 2 Return after being <br />used to generate hydropower. In addition, water is released past Central Diversion Dam <br />and /or returned via the Jeffrey Return to satisfy downstream natural flow rights and to <br />provide supplemental irrigation water to the seven Platte River canals served by NPPD. <br />The operations of both projects are closely coordinated. Irrigation demands are anticipated <br />such that the water released from Lake McConaughy arrives at the canal headgates when it <br />is needed. The amount of irrigation storage water needed to be released from Lake <br />McConaughy is determined by calculating irrigation demands, factoring in conveyance <br />losses, and considering the amount of North Platte River and South Platte River inflow to <br />the projects. The diversions at Keystone, Korty, and Central diversion dams are then <br />coordinated with the releases from Lake McConaughy to ensure that water is conveyed to <br />meet irrigation needs. <br />Each October, at the end of the irrigation season when water storage levels are at seasonal <br />lows, the Districts develop a plan for nonirrigation season storage, diversion, and <br />hydropower generation. This operating plan is subsequently modified as needed based on <br />information about upstream irrigation diversions during the past irrigation season, storage <br />levels in upstream Wyoming reservoirs, recent weather trends, and expected precipitation. <br />South Platte forecasts are also taken into account, although less reliable information is <br />available on expected South Platte River flows because there is less storage in upstream <br />reservoirs than is the case in the North Platte basin. <br />During the nonirrigation season (October through March), existing water supplies and <br />forecasts from the U.S. Bureau of Reclamation (Bureau) of future water supplies determine <br />hydropower generation and the quantity of water released from Lake McConaughy. To <br />prevent ice blockage and related icing and canal embankment sloughing problems, the <br />operational objective during the nonirrigation season is to maintain a minimum diversion at <br />2 -6 <br />