PRRIP Governance Committee Meeting and Materials

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? Compared to the previous six years which saw no discernable spring rise (i.e., pulse/peak flow) in the Platte River habitat reach, a flow of 6,490 cfs occurred at Grand Island on February 23, 2007. Subsequent rises at Grand Island occurred on Apri126 (6,120 cfs) and June 4(3,500 cfs). It is important to note that during the non-irrigation season, daily flow averages at Grand Island provide a fairly good depiction of flow conditions at the downstream end of the habitat area. Daily flow averages at the upstream end (i.e., Overton and Kearney gages) provide a less reliable indicator of flow conditions as sub-daily hydrocycling peaks and ebbs are not captured. The variability of flow conditions between the upper reaches and lower reach of the habitat area is becoming more important in EA release decisions especially as drought conditions continue. Water Year 2007 Pulse Flow Planning During WY07, EA pulse flow planning efforts were primarily in working with the Platte River Program's Adaptive Management Working Group to develop a science-based Adaptive Management Plan (AMP) for the Program. The AMP includes hypotheses and management objectives and actions to test EA pulse flows. Attachment 5, Section 1 of the PRRIP document (see Appendix D, pages 29-35) describes the coordination procedures between the EA Manager, Program Executive Director, and Project Sponsors. Program water operations for enhancing peak, or pulse, or other flows by reregulating water in the Districts systems and intentionally bypassing Program EA water are also described. • A decision was made by the Service in February 2007 to not pursue implementation of an EA pulse flow release in spring of 2007 for various reasons, including lack of congressional authorization for the PRRIP (and therefore funding for any "BA Bypass" costs), the initial stages of Program development, concerns that the safe channel capacity at the North Platte River near North Platte gage was even less than the National Weather Service (NWS) flood-level of 5.7 feet (1,980 cfs), and because the EA Bypass Agreement had yet to be signed between the Districts and the Program. It is important to note that this longer-term decision did not preclude the Service from making a shorter-term decision in WY07 to use the EA to augment a naturally occurring pulse flow event, if conditions were favorable, or for making EA releases for other purposes during WY07. The Program initiated a Water Management Study in the summer of 2007 to evaluate the feasibility of delivering 5,000 cfs of Program water to the upper end of the habitat area (e.g., Overton gage). Boyle Engineering Company plans to present their Phase I results at a workshop in December of 2007. The North Platte River Restoration Project also proceeded during the summer and fall of 2007. Efforts to increase flow conveyance by spraying 28 acres of phragmites occurred during mid-October of 2007. Information from the study and restoration effort will be considered in planning for any WY08 pulse flow release from the EA Water Year 2007, Summer (May l l- September 15) EA Releases . In 2006, a 200-acre tract of land adjacent to Audubon's Rowe Sanctuary was purchased and restoration efforts undertaken to return river channel and grassland habitat to a more natural condition (the John J. Dinan Memorial Bird Conservation Area, Dinan BCA). The acquisition Water Year 2008 EA AOP 5 October 15, 2007