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<br />, j <br /> <br />recorded spill was 0 cfs. This is based on August (-20 cfs difference). <br />September (+8 efs difference) and October (+12 efs difference). <br /> <br />If the flow rate at Indian Wash Flume was the primary source of differences, a <br />positive difference represents not enough flow rate in the canal and a negative <br />value represents unaccounted for losses in the canal. The high negative value in <br />August corresponds to higher flow rates (and canal elevations) in the canal. It <br />is possible that the estimated seepage is too low for August due to a larger <br />wetted surface area. The positive values in September and October potentially <br />represent low head-discharge readings at low flows for the rating curve. <br /> <br />. There are differences in GJWUA water orders between years. Table 2 is a <br />summary of the water orders by year. Also included is the ETo and <br />precipitation for each year. This reflects data only from the August-October. <br />1992-1994 time frame. <br /> <br />Table 2 <br />GJWUA Water Orders <br />(August - September only) <br /> <br />1992 490 288 99 15.9 1.6 <br />1993 468 247 112 16.2 4.0 <br />1994 548 292 112 15 2.2 <br /> <br />Maximum <br />Water Orders <br />(efs) <br /> <br />Average <br />Water Orders <br />(efs) <br /> <br />Minimum <br />Water Orders <br />(efs) <br /> <br />Sum <br />ETo <br />(in) <br /> <br />Sum <br />Rain <br />(in) <br /> <br />Month <br /> <br />From Attachments C. D. and E. it appears that rainfall events less than 0.25 <br />inches (per day) do nO! heavily influence the water orders. <br /> <br />. Overall. there is not a good correlation between the fluctuations in the recorded <br />spills and the fluctuations in the water orders. Only during time frames where <br />[here were large changes. was a correlation evident (such as during large <br />precipitation events). <br /> <br />From Attachment F the following observations were made: <br /> <br />The current amount of recorded spill averaged 31.700 AF per year between <br />August and October. The amount of spill necessary with the operation of <br />CHECKS ONLY was estimated to be about 14.200 AF per year. This was <br />done by evaluating the difference between the actual water orders and a <br />maximum water order rule of operation for the Highline Canal. The analysis <br />estimated that approximately 17,500 AF per year could be saved with the <br />installation of new checks. <br /> <br />Spill Volume (Average of Aug-Oct. 1992-1994) <br />Estimated Spill Volume wI CHECKS ONLY <br />POtential Water Savings <br /> <br />31.700 AF <br />14.200 AF <br />17,500 AF <br />