PRRIP Meetings South Platte River Basin 11/10/2008

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Pathfinder Modification Project. Lyle answered that Seminoe Reservoir would be more likely to have sedimentation problems. Ted Kowalski provided a water supply outlook and a summary of South Platte River conditions. Ted reported that the South Platte reservoirs are in a similar situation as last year, which is a little fuller than normal. Flows at Julesburg and Kersey are lower than at this time last year, but Kersey flows were still slightly about average. The low flows at Julesburg are due to very little precipitation in Colorado late last summer and fall. The 2008 Water Year resulted in Lower South Platte River flows not rising in the spring as they have historically, resulting in below normal flows at Kersey and Julesburg from April through July. The Colorado SNOTEL map for the South Platte Basin, November 6, 2008, shows precipitation at 77% of average. Ted explained that conditions were very favorable in the spring of 2008 for high river flows and flooding conditions along the South Platte River. Reservoirs were full and snow pack was above normal but snow melt runoff was worse than expected. The snow melted slower than anticipated due to a slow warming pattern. Ted mentioned that there needs to good snowpack, good runoff and spring rainfall events in order to see increased river flows into Nebraska during the spring. Greg Wingfield provided copies of the Draft Environmental Account 2009 Water Year Annual Operating Plan. Greg went through the document explaining the summary of 2008 operations and the projections and priorities for 2009. As a result of last year's operations, which included releases of 30,123 acre -feet, the EA ended September with 84,712 acre -feet. Greg discussed that 55% of the accrual for the year was lost through seepage and evaporation throughout the year. Greg anticipates about 41,512 acre -feet in the EA at the end of the 2009 water year, although this number could be larger based on possible EA contributions associated with the FERC waiver of non irrigation season releases. Greg explained the reasoning and effects of summer releases from the EA account. Greg pointed out that nesting activity was sited along the river at 4 of the 6 sites constructed by the USFWS (Service) and he wanted to assist flows in the critical reach. Greg described that the high river flows in May and June did not inundate any of the nests monitored by the FWS but mentioned that some nests were abandoned later in the summer due to high winds and a hail storm. The Service priorities for 2009 are all low except for flows between February 16- March 15 (high), flows between March 23 - May 10 (medium/low), flows between May 11 — September 15 (medium) and carryover storage (medium). Greg also discussed the plan for a spring pulse flow. He mentioned that some of the key obstacles of the pulse flow had changed from last year. Greg noted that river ramp rates increased from 300 cfs to 800 cfs after talking to the canal operators between Lake McConaughy and North Platte. The North Platte chokepoint had decreased in capacity from 1960 cfs to 1600 cfs do to the National Weather Service changing the flood stage.