PRRIP Governance Committee Meeting and Materials

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? Whooping Crane Fall Migration Season (Oct 1-Nov 15) & Winter period (Nov 16 - early February): No WY08 EA releases are planned at this time during these periods in order to conserve EA water for higher priority uses. Early Spring Pulse Flow Period (February - April): 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. No significant spring rise occurred in the central Platte River far six consecutive years prior to those experienced in 2007. 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 becomes increasingly more important. The Service recognizes there are many system and operational constraints and drought-related limitations that make using the EA to augment or 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 i to build upon the EA pulse flow planning progress made since WY05 with the intent of implementing an EA-facilitated pulse release during the February/March/April time period in WY08. An estimate of potential EA volume to be released for this WY08 pulse event is approximately 25,000 af (see Pulse Flow Implementation section below) A primary component of EA pulse flow planning will be to start integrating EA management with the Platte River Program's Water Plan and Adaptive Management Plan processes. It is recognized, however, that full integration in 2008 may not be possible as the Program's infrastructure and plans, as described in Program documents, is not fully in place at this time. Efforts continue by the Program to complete tasks related to pulse flow implementation, including passage of Program authorizing legislation, the EA Bypass Agreement, addressing the NWS flood-level at North Platte, and pulse flow monitoring. Consistent with the Program Water Management Process, the EA Manager will ensure, to the extent possible, that implemented pulse flows and associated monitoring and research activities are designed to incrementally help test potential concerns, system constraints, river models, and adaptive management hypotheses to be evaluated by the Platte River Program. Whooping Crane Spring Migration Season (March 23-May 10): ): If projected average daily flows of 300 cfs to 500 cfs occur at Overton during this period and gains are similar to those in WY06, shortages to the Service's dry year flow target of 1,700 cfs, at Grand Island, will again occur during this important whooping crane migration period. Hydrologic ? conditions and the status of the whooping crane migration will be closely monitored during this time. If it is determined by the Service that base flows are not providing stop-over opportunities for migrating whooping cranes in the central Platte River, EA releases may be made to augment Water Year 2008 EA AOP 10 October 15, 2007