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cfs. Due to reduced irrigation water available to Central's customers, Elwood Reservoir will not be filled in the spring. Based on the past two years, however, some natural river flow may again be diverted into the reservoir in the fall/winter to support the reservoir fishery. No water will be pumped into the Elwood Reservoir during the irrigation season except as necessary to comply with the Flow Attenuation Plan. Water may be pumped into the reservoir in September if needed to deliver irrigation water in 2008. During the irrigation season, releases will be made for irrigation customers and routed through the Districts' storage and regulating facilities, as much as possible, to generate electricity and to conserve water. A shorter than normal irrigation season and reduced delivery rate of irrigation water is again expected in WY07 (i.e., eight weeks from June to the end of August). Plans are to deliver 6.7 inches of water per acre in 2007 (up to 18 inches is allotted in normal water supply years). If drought conditions persist and similar 2003 to 2006 gains/losses are experienced between Overton, Kearney, and Grand Island, very low to zero flows are again expected to occur at Grand Island during summer and fall. Water Year 2007 Environmental Account Release Priorities Numerous hydrologic and biologic conditions must be considered throughout the year in determining EA releases. The duration and quantity of water to be released will depend on historic and existing conditions, Service target flow and pulse flow recommendations, EA volume, release priorities identified in this AOP, and experience. Based on the continuation of "very dry" conditions for the 2007 water year, the Districts' drought-conditions operation plan, and flow conditions experienced during the 2002 to 2006 "very dry" water years, the Service has identified EA release priorities for each seasonal period as described in Table 2(pages 9-11). Winter/Early Spring (December-March): Increasing the frequency, magnitude, and duration of higher flow events through the central Platte River reach to move sediment and remove in- channel vegetation through inundation, burial, and/or scouring is an overall Service flow priority, and no significant spring rise has occurred in the central Platte River for six consecutive years.* In the absence of these important hydrologic and geomorphic processes, vegetation has proliferated and become well established in the channel throughout the majority of the central Platte River habitat area. With a lack of significant pulse flow events and a continuing in-channel habitat degradational trend, using the EA to augment and/or create a pulse flow to facilitate beneficial river processes has become increasingly more important. The Service recognizes there are many system and operational constraints and drought-related limitations that make using the EA to augment ar create pulse flows in the central Platte River reach very challenging. Regardless, testing the ability of the EA to facilitate pulse flows in an attempt to restore some of these beneficial river processes, if possible, continues to be the Service's highest flow priority. In addition, the Platte River Program includes hypotheses and management objectives/actions to test EA-facilitated pulse flows in a phased, systematic approach to minimize and/or avoid potential negative consequences. The Service will continue to build upon the EA pulse flow planning progress made since WY2005 with the intent of implementing an EA-facilitated pulse release during the February/March/April time period in WY2007. Water Year 2007 EA AOP 6 January 19, 2007