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7. The C.U. analysis as described above was conducted for the dry years of 1977 and 1994, and <br /> for the average year calculated from the available records. For purposes of this study, the <br /> smaller C.U. values calculated from both analyses (dry year vs. average year) were selected <br /> as described in the following paragraphs. <br /> 3.1.1 Famine Creek Ditch and South Rock Creek Ditch <br /> As shown in Figure A-4,some of the MCR fields have been historically irrigated by combinations of different <br /> ditches. A total of approximately 131.2 acres have been historically irrigated by both the Famine and the <br /> South Rock Creek ditches. Of this total, 65 acres have been permanently removed from irrigation. Over a <br /> 44-year study period, the Famine Ditch diverted an average of 627 AF annually. During the dry years of <br /> 1977 and 1994, an average of 870 AF was diverted through the Famine Ditch'. The average annual <br /> diversion for the South Rock Creek Ditch equals 749 AF, with an average diversion of 1,380 AF <br /> corresponding to the dry years of 1977 and 1994. <br /> The analysis of active call records shows that, on average, the South Rock Creek Ditch would be out-of- <br /> priority 1 day in May, 4 days in July, 12 days in August, 15 days in September, and 14 days in October. <br /> Moreover, of the 1987-2010 period, only in 1994 was the South Rock Creek Ditch called out during the <br /> entire month of July. And only in 1994 and 2002 was the South Rock Creek Ditch out-of-priority during <br /> certain days in June(2 and 9 days respectively). Therefore,for purposes of this study, it was conservatively <br /> assumed that the South Rock Creek Ditch would be out-of-priority beginning July 15'of each year. <br /> The diversions records,adjusted so diversions would not exceed the decreed amounts(5 cfs for the Famine <br /> Creek Ditch and 8 cfs for the South Rock Creek Ditch),were then combined and applied to the Soil Moisture <br /> Budget Model. The Soil Moisture Budget Model showed that the historic C.U. for the Famine Creek and <br /> South Rock Creek ditches averaged 0.94 AF/acre over the study period. The C.U. for the dry years of 1977 <br /> and 1994 averages 1.05 AF/acre.Thus,the study period average C.U. of 0.94 AF/acre was selected.Table <br /> 8, below, summarizes the results from the Soil Moisture Budget Model run for the Famine Creek and South <br /> Rock Creek ditches. <br /> 3.1.2 Old Whetstone Sheep Creek Ditch <br /> Historically, the Old Whetstone Sheep Creek Ditch irrigated approximately 28.8 acres of hay and pasture <br /> fields (see Figure A-4). Of this total, about 22 acres are currently wetlands created as mitigation for <br /> wetlands impacted by gravel mining operations. The remaining 6.8 acres have been removed from <br /> irrigation. Irrigation records downloaded from the State's CDSS web-site were analyzed for a study period <br /> of 43 years. On average, historic diversions for irrigation at the headgate of the Old Whetstone Sheep Creek <br /> ' Irrigation was greatly reduced during the dry year of 2002 due to a wetlands study conducted in the <br /> Ranch, in cooperation with the US Army Corps of Engineers. <br /> 10 :::::RESOURCE <br />