PRRIP Governance Committee Meeting and Materials

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. Discussions with Ms. Whitmore and other Service biologists and hydrologists resulted in a decision to provide EA releases to augment river flows during the summer nesting period. It was judged that there was adequate EA supply to augment summer flows and leave enough carry-over to potentially implement a WY08 pulse flow release. A total of 34,374 af was released from the EA, initially at rates of 500 cfs and then 300 cfs, from June 28 through August 12. For the first 15 days (June 23-July 12), EA releases were conveyed down the North Platte River because NPPD was completing maintenance activities at the Sutherland Reservoir outlet. After July 12, when maintenance activities were completed at Sutherland Reservoir, EA releases were conveyed through NPPD's system. All EA releases were routed through the CNPPID system. There were no instances of "inundating flows" caused by the EA during this period as defined in the June 16, 2006 programmatic biological opinion. The Flow Attenuation Plan benchmark was exceeded once during the 2007 summer nesting period, but no EA releases were occurring at that time. As described above, 140,974 af of EA water was available at the start of the irrigation season. Evaporation and seepage loss from May through September totaled 8,968 af and EA releases totaled 34,374 af, leaving 97,633 af in the EA at the end of WY07. Appendix G-Figures 2, 3, and 4(pages 43-45) show the USGS reported daily minimum, ? maximum, and mean daily flow values at the Overton, Kearney, and Grand Island gages, respectively, for WY07. The data are from the U.S. Geological Survey (http://waterdata.usgs.gov/ne/nwis? and are provisional at this pomt m time. Appendix G-Figures 5, 6, and 7(pages 46-48) illustrates the mean daily flow and amount of EA water at the Overton, Kearney, and Grand Island gages, respectively for WY07 (provisional). The mean daily EA water at each gage is from the NE Department of Natural Resources as shown in their Daily Apportionment Reports (http://www.dnr.ne. o? v/ApportionmentslReports 2007/). For comparative purposes, Appendix G-Figures 8, 9, and 10 (pages 49-51) illustrates the mean daily flow for water years 2002 through 2007, and the WY07 EA water at the Kearney, Overton, and Grand Island gages from approximately July 1 through August 19 in a flow-duration format. WATER YEAR 2008 PROJECTIONS AND EA RELEASE PRIORITIES Water Year 2008 Projected Water Supplv The Districts provided the following predictions for SIVI and Type-of-Year for WY08 to the EA Manager on October 3, 2007. Item Prediction ? SNI, October through March 286,000 af SNI, October through April 326,000 af Type-of-Year Very Dry Water Year 2008 EA AOP 7 October 15, 2007