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, ';, ; ;. OS Report - Page Two 2,'1 (q"Z...-r. 9-'t) C> ~ C::> During the period of conservation storage from November 1 st to April 1 't, ~41 acre feet was t.) stored and subsequently distributed in accordance with Section II A and II D of the 1980 ~ Operating Plan. Distribution began on April 1, 2002 pursuant to a call for water from a Colorado CJl ditch and continued at the prescribed rates until exhausted on April 12, 2002. Beginning on November 16, 2001 and pursuant to the provision of Section III (a.k.a. Article III) of the 1980 Operating Plan, the storage of certain other inflow was also credited to the winter water account. Storage into the winter water account continued to March IS, 2002, when the distribution of 23 ,999-acre feet occurred to the appropriate accounts pursuant to Section III D of the Plan, The division of inflow between conservation storage and the winter water accounts followed established guidelines and resulted in an approximate overall 48 -to- Sl split (conservation to winter water), See Section 2 -Tables I and II, The methodology for determining the conservation , storage to winter water ratio was consistent to the method utilized in prior years. The base flow at the Arkansas River at Las Animas gage was determined during the period November 8th through November 14th with current meter measurements conducted by DWR on November 1st and November 8th and by USGS on November 7tlt. The base flow was detenninedto be 27 cfs, During the period November 15th through November 19t1t computations were made to determine the enhanced flow associated with arrival of winter water at the gage, An additional current meter measurement was conducted on November 20th by the USGS. The enhanced flow during this transition period was determined to be 61 cfs and an initial ratio for winter water and conservation storage was set at 56% for winter water (34/61) and 44% for conservation storage (27/61). A significant 'operational change in the winter water program occurred November-I9th and 20tlt when the Fort Lyon Canal ceased diversions at the main canal headgate and began to divert to off-channel storage at the Fort Lyon Storage Canal, The diversion rate at the Fort Lyon Storage Canal was over 200 cfs less than the Fort Lyon Canal had been taking at their main headgate resulting in an increased flow at the Arkansas River at Las Animas gage. A second transition period was established over the period November 19t1t through November 24th and the new enhanced flow was determined to be 170 cfs. This resulted in a winter water ratio of 84% (143/170) and a conservation storage ratio of 16% (27/170), A second set of winter water operational changes occurred in early January 2002. The Colorado Canal and Holbrook Canal began diversions for off-channel storage and the Fort Lyon Storage Canal reduced diversion to storage, then ceased diversion to storage, During the period from January ISth through January 24th the flow stabilized at an average of 121 cfs, A USGS current meter measurement was taken on January 15th. The change in operations suggested the need for a change in ratio and new ratios of 78% (94/121) for winter water and 22% (27/121) for conservation storage were established and used until the end of the winter water storage season on March 14,2002,