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Wyoming Area Office Bureau of Reclamation North Platte River Water Supply Update November 8, 2007 Page I of 2 Figure 1 shows current reservoir storage conditions for Reclamation reservoirs on the North Platte River as of November 5, 2007, and provides a comparison of total inflow, total Guernsey Reservoir outflow, and total September 30 system storage for water years 2004 through 2007, including the statistical "most probable" 2008 operations compiled from the November operating plan. The term "kaf' used in this report represents acre-feet times 1000. The North Platte total system storage of 706.3 kaf at the end of water year 2007 represents a decrease in the system storage of 99.6 kaf over water year 2006 (805.6 kaf). This system storage decrease is attributable to below average runoff. Releases from Guernsey Reservoir were discontinued on September 10, 2007, following the delivery of Central Nebraska Public Power & Irrigation District water. A daily Guernsey release of approximately 30 cis of Glendo water, under a temporary water contract with Basin Electric, continued through September 30. The North Platte Project Irrigation Districts conserved approximately 286.3 kaf of carryover storage. The total system probable inflow for 2008, which approximates an average inflow condition is estimated to be 1310.8 kaf. The total Guernsey Reservoir probable outflow for 2008 is estimated to be 1158.0 kaf and reflects an assumed full irrigation delivery for the North Platte Project contractors. The projected total system probable storage on September 30, 2008, is estimated to be 50% of average (704.7 kaf/1419.23 kaf) or 25% of the total conservation capacity of the system. Figure 2 and Figure 3 provide snow water equivalent (SWE) information expressed in inches of water for the upper and lower North Platte River basins. This early SNOTEL (snow telemetry) information shows the SWE is below average for the upper and lower basins. As of November 6, 2007, the Natural Resources Conservation Service (NRCS) reported the SWE to be 69% of average (Figure 4) for both the upper and lower basin. Table 1 shows the actual total system inflows, Guernsey outflow, and end -of -month total system storage for the month of October and the projected November through September operations based on reasonable minimum, most probable, and reasonable maximum inflow conditions. These statistical inflow conditions provide the range for Reclamation operating plans in the North Platte River Basin. The operating plans are updated monthly to reflect changing inflow conditions. This report focuses on the information associated with the November most probable operating plan. The actual total system inflows for the month of October were 80% of average (39.7 kaf/49.9 kaf). Table 1 also includes the accompanying information for water year 2007 and the 30 -year average (1978-2007) for comparison. Graph 1 through Graph 3 display this information in graphical format. Based on the November most probable North Platte River Operating Plan, the